Evaluation of a Novel Multi-Purpose Ophthalmic Block Simulator Amongst Ophthalmology Trainees

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Choo, Elizabeth W. L. Lim, Chelsea Q. L. Tan, Jordan Lee, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8727112/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 11 You are reading this latest preprint version Abstract Purpose Training to perform ophthalmic blocks is often done on actual patients by trial and error. Higher complication rates and poor patient experience occur from a suboptimal block. We assess the efficacy of a novel ophthalmic block simulator via a pilot study. Design: The production process involved 3D-printing and improvisation with readily available materials that provided excellent reproducibility of a real-life experience. Methods A prospective pilot study on ophthalmology trainees in a single centre via a 3-pronged approach before and after a supervised training workshop on the simulator was performed. Outcomes evaluated include procedural confidence, competence, accurate positioning of needle during peribulbar block and degree of akinesia after peribulbar block. Results There were significant improvements in trainee self-ranked confidence (7.57±1.27 to 8.57±1.13, p = 0.018), competence (7.71±0.95 to 8.43±0.98, p = 0.047) (n = 7), consultant-rated akinesia, competence and confidence (38.1%±29.9% to 34.8%±20.7% p = 0.766, 7.63±1.51 to 7.90±0.66 p = 0.585, and 7.57±1.64 to 7.80±0.92 p = 0.698) (18 assessments pre-workshop, 20 assessments post-workshop). There was improved mean accuracy in blocks performed on the simulator after training with the simulator (4.17±1.27 to 4.83±0.389, n = 12, p = 0.054). Conclusion This is a simple, useful, portable and low-cost ophthalmic block simulator that allows trainees to gain confidence and competence in performing these procedures. Health sciences/Diseases Health sciences/Health care Health sciences/Medical research Figures Figure 1 Figure 2 Introduction Ophthalmic regional blocks are regularly performed peri-procedure before ophthalmological procedures or surgeries, from bedside vitreous taps to cataract surgery and orbital, glaucoma or vitreoretinal surgery. With the move towards giving blocks in the operating room as opposed to the anaesthetic room, there is an increased need to get the blocks to work more effectively and quickly. However, ophthalmic blocks are often performed blindly without being able to visualize needle position during the procedure, resulting in the need to rely on the procedurist’s knowledge of anatomy and familiarity with the haptic feedback of penetrating various tissues. Ophthalmology trainees currently learn how to perform ophthalmic blocks via a “see one, do one, teach one” approach, where they observe senior colleagues perform these blocks, attempt to do the same on a real patient for the first time without any prior practice in a controlled setting, then repeat attempts on patients by trial and error and then teach the skill to future trainees. This is something that is highly suboptimal for a procedure that is done without direct visualization into penetrated periocular tissues and with potential risks to the patient. Risks include chemosis, periorbital haematoma, increased intraocular pressure, and sight-threatening complications such as retrobulbar haemorrhage, globe perforation, optic nerve injury, retinal artery occlusion and even life-threatening brainstem anesthesia. 1 Risk factors for globe perforation during peribulbar blocks include an inexperienced surgeon and multiple attempts at the procedure. 2 Also, when a peribulbar block is not given effectively in the appropriate location, especially when trainees are not accustomed to performing such procedures, insufficient anaesthesia or akinesia is common. This can result in prolonged surgery time and a higher risk of intra-operative complications. It is well-known that medical device simulation training is effective. 3–6 An ophthalmic block simulator would be helpful in improving patient safety and aneasthesia, as well as minimizing procedural complications. Such a simulator can improve confidence and competence in these procedures amongst ophthalmology trainees, and reduce stress associated with performing such procedures without prior training. While there have been a few case reports on periorbital block simulators, none are currently available commercially. In 1996, the ophthalmic retrobulbar injection simulator (ORIS) was developed, using ultrasonic sensors embedded in the mannequin’s skull to provide trainees with information on the needle tip location. 7 However, this system was only accurate when there was no obstacle between the needle tip and ultrasound sensor and could only simulate 1 type of regional block – the retrobulbar block, which is has largely been superseded by peribulbar blocks. Another system relied on an electric field-based tracking system which required the needle to be connected to an additional electric circuit, which increased the potential for disconnection and difficulty during simulation. 8, 9 Another publication detailed an electromagnetic detection system which was highly precise, however the production cost of the system was prohibitively expensive. 10 Choi et al. devised a retrobulbar anaesthesia simulator; however it did not permit direct visualization of the needle during practice with the model. 11 While an inexpensive home-assembled skull model has been developed previously, it lacks the haptic feedback of the human periorbital structures and is not anatomically accurate. 12 Thus, not only are there no ophthalmic block simulators commercially available, there are still inadequacies in the current models mentioned in current literature. Moreover, none of the simulators mentioned in present literature have re-created the conjunctiva which is essential for sub-tenons and transconjunctival peribulbar blocks. To address this gap, we have devised a novel ophthalmic block simulator to satisfy the above shortcomings. The aim of this study is to describe our simulator and to showcase our simulator’s efficacy in improving the confidence and accuracy of peribulbar blocks given by ophthalmology trainees. Methods This study was subjected to SingHealth institutional review board (IRB) waiver and adhered to the tenets of the Declaration of Helsinki. IRB waiver included waiver of consent of our human participants in the pilot study. Data was anonymized. No compensation was provided to participants in our pilot study. Creation of the simulator The simulator consists of four components: the bony orbit, the orbital contents (eyeball and orbital fat), conjunctiva and skin (Fig. 1 ). Trainees can utilize this model to learn multiple types of ophthalmic blocks – namely the peribulbar block, supraorbital block and sub-Tenon’s block. The bony orbit is 3D-printed via a real Asian orbit computed tomography (CT) scan image series uploaded into the Materialise MIMICS program (Materalise, Leuven, Belgium) and then printed using the Bambu Lab X1 Carbon (Bambu Lab, Shenzhen, People’s Republic of China) using polylactic acid (PLA) material. Using an Asian orbit CT scan image series allowed for as close a replication to performing an ophthalmic block on an Asian patient, which would be the main group of patients in Singapore or the rest of Asia. This PLA model was then used as a reverse mold to be filled with epoxy resin. The product was then treated to achieve as close to transparency as possible, to allow for real-time visualization of the needle tip by the mentor when the trainee performed a block on the model (Fig. 2 ). The eyeball was created using conventional padded bandage wrapped around a metal sphere – this replicated the haptic feel of a real human eyeball if scleral perforation were to occur, but yet permitted for simulation of varying axial lengths of the eye by varying the amount of bandage wrapped around the metal sphere, alongside varying the size of the metal sphere. This is very useful in the Asian context, as high myopia is more common in the Asian population and the associated longer axial length is known to be associated to higher risk of globe perforation from peribulbar blocks. 13 Orbital fat was simulated via using “Elmer’s Gue Unicorn Butter” (Newell Brands, GA, USA) – readily available in stores and highly affordable. Haptic feedback from penetration with a 25-gauge needle used in peribulbar blocks was similar to that experienced in a real-life setting. The conjunctiva was mimicked using “Tegaderm” (3M Company, MN, USA) – a ubiquitous material found in healthcare facilities that is cost-effective, easily replaceable and sourced. It also allowed for simulation of a subconjunctival pocket when simulating performing a sub-Tenon’s block. The skin was produced using Smooth-On Ecoflex 00–30 (Smooth-On, Macungie, Pennsylvania) and power mesh mix and a face mask mold. We tested the resilience of the individual materials used to see how many uses the simulator could withstand before component replacement was required. The bony orbit does not degrade with time as it was completely solid and does not suffer from penetration of any needles. For the skin, it could withstand at least 200–300 block attempts without changes in function, haptic sensitivity or leave holes. The orbital fat and eyeball substitutes were self-sealing and did not undergo any degradation after repeated block attempts. The conjunctiva substitute with Tegaderm needed replacement after each session where the simulator is deployed, i.e. multiple uses may be performed during the same session, fewer uses if a sub-Tenon’s block is simulated as it involves cutting the conjunctiva Tegaderm with scissors as part of simulation of the real procedure. Pilot Study Design and Administration This was a single-centre self-controlled trial that involved ophthalmology trainees from a single centre (Singapore National Eye Centre). Trainees were evaluated before and after undergoing a training workshop with the simulator and the assessment was carried out via a 3-pronged approach. During the training workshop, trainees were first asked to perform 5 peribulbar blocks on the model with their existing technique. They were assessed on whether the positioning of the needle was correct (1 – Yes or 0 – No). They were then given the opportunity to practice on the model with real-time feedback from a trainer observing the technique via direct visualization of the positioning of the needle. Thereafter, they repeated the assessment with the grading of 5 peribulbar blocks on the model. The same trainer was used throughout the pilot study to allow for consistency in correction of the residents’ technique during the workshop. Before the workshop, trainees were also given a questionnaire to grade their (a) self-assessed competence and (b) confidence in giving peribulbar blocks on a 10-point Likert scale (0 – not competent/confident, 10 – very competent/confident) ( Appendix 1 ) and (b) a questionnaire for surgical trainers (consultants) to grade residents on (i) the degree of akinesia achieved 30 seconds after they perform a peribulbar block in the operating room (measured by averaging the amount of eye movement on upward, downward and lateral gazes with 0% being complete akinesia and 100% being 0 akinesia), (ii) their confidence in the resident performing the peribulbar block and (iii) the resident’s competence on a 10-point Likert scale (0 – not competent, 10 – very competent) ( Appendix 2 ). After the workshop, the same 2 questionnaires done pre-workshop as detailed in Appendix 1 and 2 were given to trainees and their surgical trainers to repeat post-workshop, to evaluate changes in performance after practice with our simulator. Statistical analysis All statistical analysis was performed using SPSS Version 29.0.2.0. Paired t-tests were used to compare mean results for each resident before and after the workshop. The level of significance was at alpha of 0.05 but actual p values were also reported. Results A total of twelve trainees underwent the training workshop with the simulator and seven of these residents self-assessed their competence and confidence before and after using the simulator. Some trainees progressed to doing surgeries under topical anaesthesia and thus, could not be evaluated on their peribulbar block performance after the workshop. There were 18 instances of pre-workshop assessments by supervising surgical trainers (consultants) and 20 instances of post-workshop assessments by supervising consultants. These assessments were done contemporaneously in the operating room where consultants supervised trainees on their surgeries. After trainees trained with the simulator model, there was an improvement in needle positioning. Pre-workshop, trainees only had correct positioning with a mean of 4.17 out of 5 times. Post-workshop, trainees had correct positioning 4.83 out of 5 times and this improvement was close to statistical significance (p = 0.054). Table 1 Resident questionnaire – trainee self-ranking of their own confidence and competence pre- and post-workshop (n = 7). Pre-workshop Post-workshop p-value Confidence 7.57 8.57 0.018 Competence 7.71 8.43 0.047 Adequacy 72.86 77.14 0.289 The trainees’ rating of their confidence level in performing peribulbar blocks was a mean of 7.57 out of 10 pre-workshop. This confidence level significantly improved to 8.57 post-workshop (p = 0.018). The trainees’ rating of their competency in performing peribulbar blocks was a mean of 7.71 out of 10 pre-workshop. This rating significantly improved to 8.43 post-workshop (p = 0.047). However, the rating of their own adequacy of peribulbar blocks showed no significant improvement, from 72.86% to 77.14% (p = 0.289) (Table 1 ). No complications or penetrating injuries were seen amongst patients who received peribulbar blocks by our training group trainees after the workshop, compared to pre-workshop, where residents recounted various complications (chemosis n = 2, periorbital haematoma n = 1, retrobulbar haemorrhage n = 1, central retinal artery occlusion n = 1). Table 2 Consultant’s questionnaire – consultants’ grading of trainees in the operating room Pre-workshop Post-workshop p-value Confidence 7.56 7.80 0.698 Competence 7.63 7.90 0.585 Average movement in 1 direction (%)* 38.1 34.8 0.766 (n = 8, 18 individual pre-workshop assessments and 20 post-workshop assessments) *Degree of akinesia 30 seconds after performing the block (0% - complete akinesia, 100% − 0 akinesia) Consultants rated the performance of trainees performing peribulbar blocks prior to ophthalmic surgery. The rating of trainees’ performance by consultants in the operating theatre showed some improvement post-workshop in terms of their confidence in residents (from 7.56 to 7.80, p = 0.698) and how competent they felt the trainees were (from 7.63 to 7.90, p = 0.585), however this did not reach statistical significance (Table 2 ). The amount of akinesia post-peribulbar block was also compared pre-workshop versus post-workshop. Akinesia was calculated by taking the average amount of eye movement on upgaze, downgaze, rightgaze and leftgaze respectively. There was better akinesia post-peribulbar block after trainees underwent the workshop, but this was statistically insignificant, with an average of 38.1% in eye movement pre-workshop compared to 34.8% of average eye movement post-workshop (p = 0.766). Subgroup analysis was performed on the consultants’ evaluation of first year trainees (8 responses), as they would be the most inexperienced in performing ophthalmic blocks and would theoretically benefit the most from such a simulator. Analysis showed that consultants’ ratings of trainee competence showed significant improvement from a pre-workshop rating of 6.33 to 7.83 post-workshop (p < 0.001). Consultants had more confidence in the trainees post-workshop (6.17 to 7.90), but this did not reach statistical significance (p = 0.179). Discussion This is a novel ophthalmic block simulator devised using affordable, accessible materials and includes the ability to perform multiple different types of ophthalmic blocks, without the potential for patient harm or adverse outcomes to patients. Moreover, this is the first simulator involving simulation of the conjunctiva, allowing for a highly realistic simulation experience. Direct visualization of the needle with an almost transparent bony orbit is very useful in giving immediate feedback to users on the location of their blocks. The capability to replace individual parts that may have degraded with time also allows for more cost-effectiveness and less waste. Using synthetic materials (as opposed to natural material like cadaveric tissue) avoid problems related to the shelf life of biological materials and possible religious concerns with the usage of certain animal tissues. Furthermore, our model is easily portable to aid for easy transportation and deployment of the model for usage. Notably, there was significant improvement in trainee self-ranked confidence and competence, as well as surgical trainer rating of the competence of first-year trainees in performing peribulbar blocks after utilizing our simulator model. Moreover, there were no complications or penetrating eye injuries in the blocks done by trainees after the workshop, compared to the presence of complications pre-workshop, some of which could lead to blindness such as retrobulbar haemorrhage and central retinal artery occlusion. Other analysed parameters also showed positive improvement, although they were not statistically significant. A limitation would be the small sample size of our pilot study, as this is a study done in a single centre in Singapore and our ophthalmology training intake is fairly small in number. This can be mitigated by expanding our data set to involve ophthalmology trainees from other training centres. Another potential extension of our pilot study would be evaluating if anaesthesia residents could also benefit from this simulator, as anaesthesiologists do assist in performing ophthalmic blocks occasionally, especially sub-tenon’s block in the induction room prior to surgery. In conclusion, our model has successfully replicated a life-like simulation to practice ophthalmic blocks on, without sustaining any risks to a real patient or any issues associated with biological or cadaveric tissue. It has been devised using cost-effective and easily available materials and permits the training of various different types of ophthalmic blocks. Our simulator has shown to significantly improve confidence and competency amongst trainees in their administration of peribulbar blocks, and positive improvement in other evaluated factors. Declarations There are no conflicts of interest. This project was supported by the SingHealth Duke-NUS Academic Medicine Innovation Institution Innovation Seed Grant. This grant had no specific role in the conceptualization, design, data collection, analysis, decision to publish, or preparation of the manuscript. Additional Information All authors declare that they have no competing financial and non-financial interests. Funding This project was supported by the SingHealth Duke-NUS Academic Medicine Innovation Institution Innovation Seed Grant. This grant had no specific role in the conceptualization, design, data collection, analysis, decision to publish, or preparation of the manuscript. Author Contribution J.Q.H. C: Conceptualisation, Methodology, Manuscript writing, Manuscript revisionE. W. L. L: Methodology, Data analysis, Manuscript writing, Manuscript revisionC. Q. L. T: Conceptualisation, Methodology, Manuscript revisionJ. L: Conceptualisation, Methodology, Manuscript revisionR. K. Y. T: Conceptualisation, Methodology, Manuscript revisionS. A. P: Conceptualisation, Methodology, Manuscript writing, Manuscript revision Data Availability The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request, subject to institutional and ethical considerations. References Kumar C. Orbital regional anesthesia: complications and their prevention. Indian J Ophthalmol. 2006;54:77–84. Babu N, Kumar J, Kohli P, Ahuja A, Shah P, Ramasamy K. Clinical presentation and management of eyes with globe perforation during peribulbar and retrobulbar anesthesia: a retrospective case series. Korean J Ophthalmol. 2021;36:16. Farsoni S, Astolfi L, Bonfè M, Spadaro S, Volta CA. A versatile ultrasound simulation system for education and training in high-fidelity emergency scenarios. IEEE J Transl Eng Health Med. 2017;5:1–9. Siassi B, Ebrahimi M, Noori S, Sheng S, Ghosh D, Seri I. Virtual neonatal echocardiographic training system (VNETS): an echocardiographic simulator for training basic transthoracic echocardiography skills in neonates and infants. IEEE J Transl Eng Health Med. 2018;6:1–7. Hanumara NC, Begg ND, Walsh CJ, et al. Classroom to clinic: merging education and research to efficiently prototype medical devices. IEEE J Transl Eng Health Med. 2013;1:4700107. Wang C, Sun Z, Long J, et al. Development of a novel massage platform for medical training. Technol Health Care. 2020;28:89–101. Merril JR, Notaroberto NF, Laby DM, Rabinowitz AM, Piemme TE. The ophthalmic retrobulbar injection simulator (ORIS): an application of virtual reality to medical education. In: Proceedings of the Annual Symposium on Computer Application in Medical Care ; 1992:702. Mukherjee B, George B, Sivaprakasam M. An efficient capacitive sensing scheme for an ophthalmic regional anesthesia training system. In: Proceedings of the 35th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC) ; 2013; Osaka, Japan. IEEE; 2013:894–897. Mukherjee B, Venkatakrishnan JV, George B, Sivaprakasam M. Evaluation of an ophthalmic anesthesia simulation system for regional block training. Ophthalmology. 2015;122:2578–2580. Borvorntanajanya K, Suthakorn J. Hall effect sensing workspace estimation with non-permanent magnetic needle for eye anesthesia training system via robotic experiments. In: Proceedings of the IEEE International Conference on Robotics and Automation (ICRA) ; 2018; Brisbane, Australia. IEEE; 2018:4019–4024. Choi YJ, Joo YH, Oh BL, Lee JC. 3D-printed ophthalmic retrobulbar anesthesia simulator: mimicking anatomical structures and providing tactile sensations. IEEE J Transl Eng Health Med. 2021;9:1–6. Chua AW, Chua MJ, Harrisberg BP, Kumar CM. Inexpensive home-assembled human skull model for training and learning the peribulbar block technique. Anaesth Intensive Care. 2022;50:400–402. Duker JS, Belmont JB, Benson WE, et al. Inadvertent globe perforation during retrobulbar and peribulbar anesthesia: patient characteristics, surgical management, and visual outcome. Ophthalmology. 1991;98:519–526. Additional Declarations No competing interests reported. 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L.","lastName":"Tan","suffix":""},{"id":606361413,"identity":"6d9380f4-117d-422b-88ad-adea7862d934","order_by":3,"name":"Jordan Lee","email":"","orcid":"","institution":"Sunshine Coast Hospital and Health Service","correspondingAuthor":false,"prefix":"","firstName":"Jordan","middleName":"","lastName":"Lee","suffix":""},{"id":606361415,"identity":"dacde0da-6bc4-4c5a-8f51-9f4d7d70085e","order_by":4,"name":"Royston K. Y. Tan","email":"","orcid":"","institution":"Singapore Eye Research Institute","correspondingAuthor":false,"prefix":"","firstName":"Royston","middleName":"K. Y.","lastName":"Tan","suffix":""},{"id":606361416,"identity":"f4300697-52ea-4687-8384-157f2fd69cd8","order_by":5,"name":"Shamira A. 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With the move towards giving blocks in the operating room as opposed to the anaesthetic room, there is an increased need to get the blocks to work more effectively and quickly. However, ophthalmic blocks are often performed blindly without being able to visualize needle position during the procedure, resulting in the need to rely on the procedurist\u0026rsquo;s knowledge of anatomy and familiarity with the haptic feedback of penetrating various tissues. Ophthalmology trainees currently learn how to perform ophthalmic blocks via a \u0026ldquo;see one, do one, teach one\u0026rdquo; approach, where they observe senior colleagues perform these blocks, attempt to do the same on a real patient for the first time without any prior practice in a controlled setting, then repeat attempts on patients by trial and error and then teach the skill to future trainees. This is something that is highly suboptimal for a procedure that is done without direct visualization into penetrated periocular tissues and with potential risks to the patient. Risks include chemosis, periorbital haematoma, increased intraocular pressure, and sight-threatening complications such as retrobulbar haemorrhage, globe perforation, optic nerve injury, retinal artery occlusion and even life-threatening brainstem anesthesia.\u003csup\u003e1\u003c/sup\u003e Risk factors for globe perforation during peribulbar blocks include an inexperienced surgeon and multiple attempts at the procedure.\u003csup\u003e2\u003c/sup\u003e Also, when a peribulbar block is not given effectively in the appropriate location, especially when trainees are not accustomed to performing such procedures, insufficient anaesthesia or akinesia is common. This can result in prolonged surgery time and a higher risk of intra-operative complications.\u003c/p\u003e \u003cp\u003eIt is well-known that medical device simulation training is effective.\u003csup\u003e3\u0026ndash;6\u003c/sup\u003e An ophthalmic block simulator would be helpful in improving patient safety and aneasthesia, as well as minimizing procedural complications. Such a simulator can improve confidence and competence in these procedures amongst ophthalmology trainees, and reduce stress associated with performing such procedures without prior training. While there have been a few case reports on periorbital block simulators, none are currently available commercially. In 1996, the ophthalmic retrobulbar injection simulator (ORIS) was developed, using ultrasonic sensors embedded in the mannequin\u0026rsquo;s skull to provide trainees with information on the needle tip location.\u003csup\u003e7\u003c/sup\u003e However, this system was only accurate when there was no obstacle between the needle tip and ultrasound sensor and could only simulate 1 type of regional block \u0026ndash; the retrobulbar block, which is has largely been superseded by peribulbar blocks. Another system relied on an electric field-based tracking system which required the needle to be connected to an additional electric circuit, which increased the potential for disconnection and difficulty during simulation.\u003csup\u003e8, 9\u003c/sup\u003e Another publication detailed an electromagnetic detection system which was highly precise, however the production cost of the system was prohibitively expensive.\u003csup\u003e10\u003c/sup\u003e Choi et al. devised a retrobulbar anaesthesia simulator; however it did not permit direct visualization of the needle during practice with the model.\u003csup\u003e11\u003c/sup\u003e While an inexpensive home-assembled skull model has been developed previously, it lacks the haptic feedback of the human periorbital structures and is not anatomically accurate.\u003csup\u003e12\u003c/sup\u003e Thus, not only are there no ophthalmic block simulators commercially available, there are still inadequacies in the current models mentioned in current literature. Moreover, none of the simulators mentioned in present literature have re-created the conjunctiva which is essential for sub-tenons and transconjunctival peribulbar blocks.\u003c/p\u003e \u003cp\u003eTo address this gap, we have devised a novel ophthalmic block simulator to satisfy the above shortcomings. The aim of this study is to describe our simulator and to showcase our simulator\u0026rsquo;s efficacy in improving the confidence and accuracy of peribulbar blocks given by ophthalmology trainees.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e This study was subjected to SingHealth institutional review board (IRB) waiver and adhered to the tenets of the Declaration of Helsinki. IRB waiver included waiver of consent of our human participants in the pilot study. Data was anonymized. No compensation was provided to participants in our pilot study.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eCreation of the simulator\u003c/h2\u003e \u003cp\u003eThe simulator consists of four components: the bony orbit, the orbital contents (eyeball and orbital fat), conjunctiva and skin (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Trainees can utilize this model to learn multiple types of ophthalmic blocks \u0026ndash; namely the peribulbar block, supraorbital block and sub-Tenon\u0026rsquo;s block.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe bony orbit is 3D-printed via a real Asian orbit computed tomography (CT) scan image series uploaded into the Materialise MIMICS program (Materalise, Leuven, Belgium) and then printed using the Bambu Lab X1 Carbon (Bambu Lab, Shenzhen, People\u0026rsquo;s Republic of China) using polylactic acid (PLA) material. Using an Asian orbit CT scan image series allowed for as close a replication to performing an ophthalmic block on an Asian patient, which would be the main group of patients in Singapore or the rest of Asia. This PLA model was then used as a reverse mold to be filled with epoxy resin. The product was then treated to achieve as close to transparency as possible, to allow for real-time visualization of the needle tip by the mentor when the trainee performed a block on the model (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The eyeball was created using conventional padded bandage wrapped around a metal sphere \u0026ndash; this replicated the haptic feel of a real human eyeball if scleral perforation were to occur, but yet permitted for simulation of varying axial lengths of the eye by varying the amount of bandage wrapped around the metal sphere, alongside varying the size of the metal sphere. This is very useful in the Asian context, as high myopia is more common in the Asian population and the associated longer axial length is known to be associated to higher risk of globe perforation from peribulbar blocks.\u003csup\u003e13\u003c/sup\u003e Orbital fat was simulated via using \u0026ldquo;Elmer\u0026rsquo;s Gue Unicorn Butter\u0026rdquo; (Newell Brands, GA, USA) \u0026ndash; readily available in stores and highly affordable. Haptic feedback from penetration with a 25-gauge needle used in peribulbar blocks was similar to that experienced in a real-life setting. The conjunctiva was mimicked using \u0026ldquo;Tegaderm\u0026rdquo; (3M Company, MN, USA) \u0026ndash; a ubiquitous material found in healthcare facilities that is cost-effective, easily replaceable and sourced. It also allowed for simulation of a subconjunctival pocket when simulating performing a sub-Tenon\u0026rsquo;s block. The skin was produced using Smooth-On Ecoflex 00\u0026ndash;30 (Smooth-On, Macungie, Pennsylvania) and power mesh mix and a face mask mold.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eWe tested the resilience of the individual materials used to see how many uses the simulator could withstand before component replacement was required. The bony orbit does not degrade with time as it was completely solid and does not suffer from penetration of any needles. For the skin, it could withstand at least 200\u0026ndash;300 block attempts without changes in function, haptic sensitivity or leave holes. The orbital fat and eyeball substitutes were self-sealing and did not undergo any degradation after repeated block attempts. The conjunctiva substitute with Tegaderm needed replacement after each session where the simulator is deployed, i.e. multiple uses may be performed during the same session, fewer uses if a sub-Tenon\u0026rsquo;s block is simulated as it involves cutting the conjunctiva Tegaderm with scissors as part of simulation of the real procedure.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003ePilot Study Design and Administration\u003c/h3\u003e\n\u003cp\u003eThis was a single-centre self-controlled trial that involved ophthalmology trainees from a single centre (Singapore National Eye Centre). Trainees were evaluated before and after undergoing a training workshop with the simulator and the assessment was carried out via a 3-pronged approach.\u003c/p\u003e \u003cp\u003eDuring the training workshop, trainees were first asked to perform 5 peribulbar blocks on the model with their existing technique. They were assessed on whether the positioning of the needle was correct (1 \u0026ndash; Yes or 0 \u0026ndash; No). They were then given the opportunity to practice on the model with real-time feedback from a trainer observing the technique via direct visualization of the positioning of the needle. Thereafter, they repeated the assessment with the grading of 5 peribulbar blocks on the model. The same trainer was used throughout the pilot study to allow for consistency in correction of the residents\u0026rsquo; technique during the workshop.\u003c/p\u003e \u003cp\u003eBefore the workshop, trainees were also given a questionnaire to grade their (a) self-assessed competence and (b) confidence in giving peribulbar blocks on a 10-point Likert scale (0 \u0026ndash; not competent/confident, 10 \u0026ndash; very competent/confident) (\u003cb\u003eAppendix 1\u003c/b\u003e) and (b) a questionnaire for surgical trainers (consultants) to grade residents on (i) the degree of akinesia achieved 30 seconds after they perform a peribulbar block in the operating room (measured by averaging the amount of eye movement on upward, downward and lateral gazes with 0% being complete akinesia and 100% being 0 akinesia), (ii) their confidence in the resident performing the peribulbar block and (iii) the resident\u0026rsquo;s competence on a 10-point Likert scale (0 \u0026ndash; not competent, 10 \u0026ndash; very competent) (\u003cb\u003eAppendix 2\u003c/b\u003e).\u003c/p\u003e \u003cp\u003eAfter the workshop, the same 2 questionnaires done pre-workshop as detailed in Appendix 1 and 2 were given to trainees and their surgical trainers to repeat post-workshop, to evaluate changes in performance after practice with our simulator.\u003c/p\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eAll statistical analysis was performed using SPSS Version 29.0.2.0. Paired t-tests were used to compare mean results for each resident before and after the workshop. The level of significance was at alpha of 0.05 but actual p values were also reported.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eA total of twelve trainees underwent the training workshop with the simulator and seven of these residents self-assessed their competence and confidence before and after using the simulator. Some trainees progressed to doing surgeries under topical anaesthesia and thus, could not be evaluated on their peribulbar block performance after the workshop. There were 18 instances of pre-workshop assessments by supervising surgical trainers (consultants) and 20 instances of post-workshop assessments by supervising consultants. These assessments were done contemporaneously in the operating room where consultants supervised trainees on their surgeries.\u003c/p\u003e \u003cp\u003eAfter trainees trained with the simulator model, there was an improvement in needle positioning. Pre-workshop, trainees only had correct positioning with a mean of 4.17 out of 5 times. Post-workshop, trainees had correct positioning 4.83 out of 5 times and this improvement was close to statistical significance (p\u0026thinsp;=\u0026thinsp;0.054).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eResident questionnaire \u0026ndash; trainee self-ranking of their own confidence and competence pre- and post-workshop (n\u0026thinsp;=\u0026thinsp;7).\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePre-workshop\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePost-workshop\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConfidence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e8.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.018\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCompetence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7.71\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e8.43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.047\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAdequacy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e72.86\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e77.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.289\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe trainees\u0026rsquo; rating of their confidence level in performing peribulbar blocks was a mean of 7.57 out of 10 pre-workshop. This confidence level significantly improved to 8.57 post-workshop (p\u0026thinsp;=\u0026thinsp;0.018). The trainees\u0026rsquo; rating of their competency in performing peribulbar blocks was a mean of 7.71 out of 10 pre-workshop. This rating significantly improved to 8.43 post-workshop (p\u0026thinsp;=\u0026thinsp;0.047). However, the rating of their own adequacy of peribulbar blocks showed no significant improvement, from 72.86% to 77.14% (p\u0026thinsp;=\u0026thinsp;0.289) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). No complications or penetrating injuries were seen amongst patients who received peribulbar blocks by our training group trainees after the workshop, compared to pre-workshop, where residents recounted various complications (chemosis n\u0026thinsp;=\u0026thinsp;2, periorbital haematoma n\u0026thinsp;=\u0026thinsp;1, retrobulbar haemorrhage n\u0026thinsp;=\u0026thinsp;1, central retinal artery occlusion n\u0026thinsp;=\u0026thinsp;1).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eConsultant\u0026rsquo;s questionnaire \u0026ndash; consultants\u0026rsquo; grading of trainees in the operating room\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePre-workshop\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePost-workshop\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConfidence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e7.80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.698\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCompetence\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e7.90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.585\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAverage movement in 1 direction (%)*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e38.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e34.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.766\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003e(n\u0026thinsp;=\u0026thinsp;8, 18 individual pre-workshop assessments and 20 post-workshop assessments)\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003e*Degree of akinesia 30 seconds after performing the block (0% - complete akinesia, 100% \u0026minus;\u0026thinsp;0 akinesia)\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eConsultants rated the performance of trainees performing peribulbar blocks prior to ophthalmic surgery. The rating of trainees\u0026rsquo; performance by consultants in the operating theatre showed some improvement post-workshop in terms of their confidence in residents (from 7.56 to 7.80, p\u0026thinsp;=\u0026thinsp;0.698) and how competent they felt the trainees were (from 7.63 to 7.90, p\u0026thinsp;=\u0026thinsp;0.585), however this did not reach statistical significance (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The amount of akinesia post-peribulbar block was also compared pre-workshop versus post-workshop. Akinesia was calculated by taking the average amount of eye movement on upgaze, downgaze, rightgaze and leftgaze respectively. There was better akinesia post-peribulbar block after trainees underwent the workshop, but this was statistically insignificant, with an average of 38.1% in eye movement pre-workshop compared to 34.8% of average eye movement post-workshop (p\u0026thinsp;=\u0026thinsp;0.766).\u003c/p\u003e \u003cp\u003eSubgroup analysis was performed on the consultants\u0026rsquo; evaluation of first year trainees (8 responses), as they would be the most inexperienced in performing ophthalmic blocks and would theoretically benefit the most from such a simulator. Analysis showed that consultants\u0026rsquo; ratings of trainee competence showed significant improvement from a pre-workshop rating of 6.33 to 7.83 post-workshop (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Consultants had more confidence in the trainees post-workshop (6.17 to 7.90), but this did not reach statistical significance (p\u0026thinsp;=\u0026thinsp;0.179).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis is a novel ophthalmic block simulator devised using affordable, accessible materials and includes the ability to perform multiple different types of ophthalmic blocks, without the potential for patient harm or adverse outcomes to patients. Moreover, this is the first simulator involving simulation of the conjunctiva, allowing for a highly realistic simulation experience. Direct visualization of the needle with an almost transparent bony orbit is very useful in giving immediate feedback to users on the location of their blocks. The capability to replace individual parts that may have degraded with time also allows for more cost-effectiveness and less waste. Using synthetic materials (as opposed to natural material like cadaveric tissue) avoid problems related to the shelf life of biological materials and possible religious concerns with the usage of certain animal tissues. Furthermore, our model is easily portable to aid for easy transportation and deployment of the model for usage.\u003c/p\u003e \u003cp\u003eNotably, there was significant improvement in trainee self-ranked confidence and competence, as well as surgical trainer rating of the competence of first-year trainees in performing peribulbar blocks after utilizing our simulator model. Moreover, there were no complications or penetrating eye injuries in the blocks done by trainees after the workshop, compared to the presence of complications pre-workshop, some of which could lead to blindness such as retrobulbar haemorrhage and central retinal artery occlusion. Other analysed parameters also showed positive improvement, although they were not statistically significant.\u003c/p\u003e \u003cp\u003eA limitation would be the small sample size of our pilot study, as this is a study done in a single centre in Singapore and our ophthalmology training intake is fairly small in number. This can be mitigated by expanding our data set to involve ophthalmology trainees from other training centres. Another potential extension of our pilot study would be evaluating if anaesthesia residents could also benefit from this simulator, as anaesthesiologists do assist in performing ophthalmic blocks occasionally, especially sub-tenon\u0026rsquo;s block in the induction room prior to surgery.\u003c/p\u003e \u003cp\u003eIn conclusion, our model has successfully replicated a life-like simulation to practice ophthalmic blocks on, without sustaining any risks to a real patient or any issues associated with biological or cadaveric tissue. It has been devised using cost-effective and easily available materials and permits the training of various different types of ophthalmic blocks. Our simulator has shown to significantly improve confidence and competency amongst trainees in their administration of peribulbar blocks, and positive improvement in other evaluated factors.\u003c/p\u003e "},{"header":"Declarations","content":"There are no conflicts of interest. This project was supported by the SingHealth Duke-NUS Academic Medicine Innovation Institution Innovation Seed Grant. This grant had no specific role in the conceptualization, design, data collection, analysis, decision to publish, or preparation of the manuscript. \u003ch2\u003eAdditional Information\u003c/h2\u003e \u003cp\u003eAll authors declare that they have no competing financial and non-financial interests.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eThis project was supported by the SingHealth Duke-NUS Academic Medicine Innovation Institution Innovation Seed Grant. This grant had no specific role in the conceptualization, design, data collection, analysis, decision to publish, or preparation of the manuscript.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eJ.Q.H. C: Conceptualisation, Methodology, Manuscript writing, Manuscript revisionE. W. L. L: Methodology, Data analysis, Manuscript writing, Manuscript revisionC. Q. L. T: Conceptualisation, Methodology, Manuscript revisionJ. L: Conceptualisation, Methodology, Manuscript revisionR. K. Y. T: Conceptualisation, Methodology, Manuscript revisionS. A. P: Conceptualisation, Methodology, Manuscript writing, Manuscript revision\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request, subject to institutional and ethical considerations.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eKumar C. Orbital regional anesthesia: complications and their prevention. \u003cem\u003eIndian J Ophthalmol.\u003c/em\u003e 2006;54:77\u0026ndash;84.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBabu N, Kumar J, Kohli P, Ahuja A, Shah P, Ramasamy K. Clinical presentation and management of eyes with globe perforation during peribulbar and retrobulbar anesthesia: a retrospective case series. \u003cem\u003eKorean J Ophthalmol.\u003c/em\u003e 2021;36:16.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFarsoni S, Astolfi L, Bonf\u0026egrave; M, Spadaro S, Volta CA. A versatile ultrasound simulation system for education and training in high-fidelity emergency scenarios. \u003cem\u003eIEEE J Transl Eng Health Med.\u003c/em\u003e 2017;5:1\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSiassi B, Ebrahimi M, Noori S, Sheng S, Ghosh D, Seri I. Virtual neonatal echocardiographic training system (VNETS): an echocardiographic simulator for training basic transthoracic echocardiography skills in neonates and infants. \u003cem\u003eIEEE J Transl Eng Health Med.\u003c/em\u003e 2018;6:1\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHanumara NC, Begg ND, Walsh CJ, et al. Classroom to clinic: merging education and research to efficiently prototype medical devices. \u003cem\u003eIEEE J Transl Eng Health Med.\u003c/em\u003e 2013;1:4700107.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWang C, Sun Z, Long J, et al. Development of a novel massage platform for medical training. \u003cem\u003eTechnol Health Care.\u003c/em\u003e 2020;28:89\u0026ndash;101.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMerril JR, Notaroberto NF, Laby DM, Rabinowitz AM, Piemme TE. The ophthalmic retrobulbar injection simulator (ORIS): an application of virtual reality to medical education. In: \u003cem\u003eProceedings of the Annual Symposium on Computer Application in Medical Care\u003c/em\u003e; 1992:702.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMukherjee B, George B, Sivaprakasam M. An efficient capacitive sensing scheme for an ophthalmic regional anesthesia training system. In: \u003cem\u003eProceedings of the 35th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC)\u003c/em\u003e; 2013; Osaka, Japan. IEEE; 2013:894\u0026ndash;897.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMukherjee B, Venkatakrishnan JV, George B, Sivaprakasam M. Evaluation of an ophthalmic anesthesia simulation system for regional block training. \u003cem\u003eOphthalmology.\u003c/em\u003e 2015;122:2578\u0026ndash;2580.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBorvorntanajanya K, Suthakorn J. Hall effect sensing workspace estimation with non-permanent magnetic needle for eye anesthesia training system via robotic experiments. In: \u003cem\u003eProceedings of the IEEE International Conference on Robotics and Automation (ICRA)\u003c/em\u003e; 2018; Brisbane, Australia. IEEE; 2018:4019\u0026ndash;4024.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChoi YJ, Joo YH, Oh BL, Lee JC. 3D-printed ophthalmic retrobulbar anesthesia simulator: mimicking anatomical structures and providing tactile sensations. \u003cem\u003eIEEE J Transl Eng Health Med.\u003c/em\u003e 2021;9:1\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChua AW, Chua MJ, Harrisberg BP, Kumar CM. Inexpensive home-assembled human skull model for training and learning the peribulbar block technique. \u003cem\u003eAnaesth Intensive Care.\u003c/em\u003e 2022;50:400\u0026ndash;402.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDuker JS, Belmont JB, Benson WE, et al. Inadvertent globe perforation during retrobulbar and peribulbar anesthesia: patient characteristics, surgical management, and visual outcome. \u003cem\u003eOphthalmology.\u003c/em\u003e 1991;98:519\u0026ndash;526.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-8727112/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8727112/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e \u003cp\u003eTraining to perform ophthalmic blocks is often done on actual patients by trial and error. Higher complication rates and poor patient experience occur from a suboptimal block. We assess the efficacy of a novel ophthalmic block simulator via a pilot study.\u003c/p\u003e\u003ch2\u003eDesign:\u003c/h2\u003e \u003cp\u003eThe production process involved 3D-printing and improvisation with readily available materials that provided excellent reproducibility of a real-life experience.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eA prospective pilot study on ophthalmology trainees in a single centre via a 3-pronged approach before and after a supervised training workshop on the simulator was performed. Outcomes evaluated include procedural confidence, competence, accurate positioning of needle during peribulbar block and degree of akinesia after peribulbar block.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThere were significant improvements in trainee self-ranked confidence (7.57\u0026plusmn;1.27 to 8.57\u0026plusmn;1.13, p\u0026thinsp;=\u0026thinsp;0.018), competence (7.71\u0026plusmn;0.95 to 8.43\u0026plusmn;0.98, p\u0026thinsp;=\u0026thinsp;0.047) (n\u0026thinsp;=\u0026thinsp;7), consultant-rated akinesia, competence and confidence (38.1%\u0026plusmn;29.9% to 34.8%\u0026plusmn;20.7% p\u0026thinsp;=\u0026thinsp;0.766, 7.63\u0026plusmn;1.51 to 7.90\u0026plusmn;0.66 p\u0026thinsp;=\u0026thinsp;0.585, and 7.57\u0026plusmn;1.64 to 7.80\u0026plusmn;0.92 p\u0026thinsp;=\u0026thinsp;0.698) (18 assessments pre-workshop, 20 assessments post-workshop). There was improved mean accuracy in blocks performed on the simulator after training with the simulator (4.17\u0026plusmn;1.27 to 4.83\u0026plusmn;0.389, n\u0026thinsp;=\u0026thinsp;12, p\u0026thinsp;=\u0026thinsp;0.054).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThis is a simple, useful, portable and low-cost ophthalmic block simulator that allows trainees to gain confidence and competence in performing these procedures.\u003c/p\u003e","manuscriptTitle":"Evaluation of a Novel Multi-Purpose Ophthalmic Block Simulator Amongst Ophthalmology Trainees","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-18 08:37:48","doi":"10.21203/rs.3.rs-8727112/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-18T14:27:53+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-15T10:07:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"265841544666706447479019882665141678461","date":"2026-04-15T09:31:55+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-02T15:57:46+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"108284391660978926353025763608552864638","date":"2026-03-30T12:37:21+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"172915496791959576118468459385429458798","date":"2026-03-28T13:16:26+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-13T13:09:30+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-02-05T14:52:31+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-02-02T00:58:28+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-02-02T00:57:39+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2026-01-29T04:35:44+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"62a29537-5348-447a-843e-0f48e6a6be51","owner":[],"postedDate":"March 18th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":64526685,"name":"Health sciences/Diseases"},{"id":64526686,"name":"Health sciences/Health care"},{"id":64526687,"name":"Health sciences/Medical research"}],"tags":[],"updatedAt":"2026-05-18T12:53:56+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-18 08:37:48","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8727112","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8727112","identity":"rs-8727112","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}