Transoral endoscopic-guided subepiglottic cyst excision in two standing horses using a polypectomy snare

Transoral endoscopic-guided subepiglottic cyst excision in two standing horses using a polypectomy snare | Authorea try { document.documentElement.classList.add('js'); } catch (e) { } var _gaq = _gaq || []; _gaq.push(['_setAccount', 'G-8VDV14Y67G']); _gaq.push(['_trackPageview']); (function() { var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s); })(); Skip to main content Preprints Collections Wiley Open Research IET Open Research Ecological Society of Japan All Collections About About Authorea FAQs Contact Us Quick Search anywhere Search for preprint articles, keywords, etc. Search Search ADVANCED SEARCH SCROLL Equine Veterinary Education This is a preprint and has not been peer reviewed. Data may be preliminary. 1 May 2025 V1 Latest version Share on Transoral endoscopic-guided subepiglottic cyst excision in two standing horses using a polypectomy snare Authors : Emily J.F. Wall 0009-0002-0927-7578 [email protected] , Florence E. Hillen , and Henry O'Neill 0000-0002-6899-027X Authors Info & Affiliations https://doi.org/10.22541/au.174609745.55127889/v1 Published Equine Veterinary Education Version of record Peer review timeline 344 views 184 downloads Contents Abstract Supplementary Material Information & Authors Metrics & Citations View Options References Figures Tables Media Share Abstract backend=biber, style=alphabetic, sorting=ynt ]biblatex Subepiglottic cysts form within the aryepiglottic tissue of the equine upper airway and are thought to arise from remnants of the embryonic thyroglossal duct, craniopharyngeal duct or Ranke’s pouch. The clinical presentation of affected horses can vary, with larger cysts usually associated with symptoms such as dysphasia, exercise intolerance, and epiglottic entrapment. Incidental recognition of asymptomatic cases can occur during routine endoscopic examination. Various surgical approaches and techniques for cyst excision have been described and are most commonly performed under general anaesthesia. This case report describes an alternative surgical technique in two horses where cyst excision was performed under standing sedation using a transoral approach with endoscopic guidance. A four-wire electrocautery polypectomy snare was used to encircle and excise the cyst(s) in toto . The technique offers advantages including improved visualisation of the surgical field and reduced complications usually associated with general anaesthesia. In both cases, the surgery was well tolerated, and the cysts were successfully removed without complication and recoveries were uneventful. Transoral endoscopic-guided subepiglottic cyst excision in two standing horses using a polypectomy snare Emily J.F. Wall 1 , Florence E. Hillen 1 , Henry D. O’Neill 2 1 School of Veterinary Medicine and S cience, University of Nottingham, Sutton Bonington Campus, Leicestershire, LE12 5RD 2 Donnington Grove Veterinary Surgery, Oxford Road, Newbury, Berkshire RG14 2JB, UK. Contact details: [email protected] Present address: Emily J.F Wall, (University of Nottingham, Sutton Bonington Campus, Leicestershire, LE12 5RD) Summary Subepiglottic cysts form within the aryepiglottic tissue of the equine upper airway and are thought to arise from remnants of the embryonic thyroglossal duct, craniopharyngeal duct or Ranke’s pouch. The clinical presentation of affected horses can vary, with larger cysts usually associated with symptoms such as dysphasia, exercise intolerance, and epiglottic entrapment. Incidental recognition of asymptomatic cases can occur during routine endoscopic examination. Various surgical approaches and techniques for cyst excision have been described and are most commonly performed under general anaesthesia. This case report describes an alternative surgical technique in two horses where cyst excision was performed under standing sedation using a transoral approach with endoscopic guidance. A four-wire electrocautery polypectomy snare was used to encircle and excise the cyst(s) in toto . The technique offers advantages including improved visualisation of the surgical field and reduced complications usually associated with general anaesthesia. In both cases, the surgery was well tolerated, and the cysts were successfully removed without complication and recoveries were uneventful. Keywords: polypectomy snare, subepiglottic, aryepiglottic, cyst, standing, surgery, horse backend=biber, style=alphabetic, sorting=ynt ]biblatex Introduction Subepiglottic cysts (SEC) are occasionally observed within the equine aryepiglottic tissue, typically in neonates and yearlings (Salz et al, 2013). There is speculation that congenital SECs arise from the embryonic precursor of the thyroglossal duct, craniopharyngeal duct or Ranke’s pouch (Robertson, 1991). However, reports in mature horses suggest SECs may be acquired secondary to chronic pharyngeal inflammation (Aitken and Parente, 2011) or trauma (Sullivan and Parente, 2003). Most affected horses are asymptomatic with SECs detected incidentally during routine endoscopic examination (Salz et al, 2013). Clinical signs in symptomatic patients include stertorous breathing, exercise intolerance, coughing, nasal discharge, dysphagia and aspiration pneumonia (Salz et al, 2013). Signs commonly manifest on commencing exercise (Salz et al, 2013). Dysphagia, soft palate displacement, and aspiration have been observed in neonates (Stick and Boles, 1980). Successful treatment requires complete ablation of the SEC lining, typically by resecting of affected tissues. Subepiglottic tissues have been accessed by several methods including transoral (Tulleners, 1991), transnasal (Parente, 2015), laryngotomy (Stick and Boles, 1980), and pharyngotomy approaches (Salz et al, 2013). Surgery is commonly performed under general anaesthesia, although transnasal laser excision performed standing is described (Parente, 2015). This report details a transoral, endoscopic-guided SEC excision in two standing horses using a polypectomy snare. Ensnarement and transection of cysts was prompt with total resection achieved in both cases. This \soutnovel alternative technique expands the repertoire of upper airway surgeries achievable as a standing procedure. Case History and Clinical Findings Case One A 6-month-old Highland pony filly presented to Donnington Grove Equine Clinic for elective excision of a SEC. Stertorous breathing and a mild bilateral mucoid nasal discharge were observed shortly after birth. Endoscopic examination at 12 days of age revealed a SEC. Despite persistent clinical signs, surgery was delayed until weaning at the owner’s request. In the interim, no other complications were reported. Case Two A 1-year-old Thoroughbred colt was presented to the same clinic for surgical management of an epiglottic entrapment. No clinical signs were reported, with the entrapment only identified during pre-sales endoscopic examination. Case One: Following admission, endoscopic evaluation revealed a dorsally elevated soft palate and epiglottis, and a narrowed nasopharynx. During deglutition, a large, solitary centrally located SEC was visible ( Figure 1 and Supplementary video 1 ) with no evidence of concurrent epiglottic entrapment. Case Two: Pre-surgical endoscopy of the thoroughbred colt revealed intermittent entrapment of the epiglottis and a cluster of three small SEC within the right aryepiglottic tissue ( Figure 2 ). Episodic intermittent dorsal displacement of the soft palate was noted ( Supplementary video 2 ). Treatment Surgical excision of the SECs was advised for both cases. This was performed under standing sedation with the horses restrained in stocks. Horses were sedated with detomidine hydrochloride 1 (0.01 mg/kg bwt i.v.) and butorphanol tartrate 1 (0.01 mg/kg bwt i.v.). A bolus of morphine sulphate 2 (0.12 mg/kg bwt i.v.) was administered immediately before surgery. Once an acceptable plane of sedation was achieved, a headstand was used to elevate and extend the head and neck so that the ventral aspect of the mandible was parallel to the floor. A dental speculum (Equivet Millenium) 3 was used to maximally part the upper and lower incisors, optimising caudal oral cavity visualisation. The buccal, palatal and lingual mucosa were partially desensitised with 20mls of lidocaine hydrochloride 4 2% w/v topically applied using a 20ml syringe and 18-gauge needle. An additional 30mls of lidocaine hydrochloride 4 2% w/v was divided and injected at eight sites into the submucosa at the junction of the soft and hard palates to anaesthetise the soft palate. To facilitate injection, the needle hub was grasped using a pair of extended-length (27cm) Mixter artery forceps, with a narrow bore extension set 5 (Baxter, EMC0062M) connected between syringe and needle. A customised protective guard was placed into the caudal oral cavity and used to elevate and dorsally displace the soft palate, improving oropharyngeal access. A hollow tube attached to the end of the guard, through which the flexible endoscope was passed, minimised the risk of damage to the endoscope from dental contact ( Supplementary figure 1 ). Once visualised endoscopically, a further 20mls of lidocaine hydrochloride 4 2% w/v was applied topically to the SEC and surrounding subepiglottic tissue through the biopsy channel of the endoscope. A 63.5cm long 5mm diameter rigid plastic infusion pipette 6 (Infusion pipette 19057) was heated using an ambient air-fuel burning tool. Approximately 15cm of the length at the non-Luer end was bent to match the curvature of the caudal tongue ( Figure 3 ). A four-wire polypectomy snare was passed through the lumen of the insemination pipette until the tip emerged from the end ( Figure 4 ). With the wire snare fully opened, the shaft of a pair of bronchoesophageal forceps 7 (Karl Storz, 60370 UC) was passed though the centre of the loop and into the oropharynx with endoscopic guidance. The forceps were used to grasp the cyst. The open wire snare was then passed over the shaft of the forceps and around the base of the cyst, using the rigid infusion pipette as a guide/push rod ( Figure 5 ). The circumference of the ensnared cyst was inspected to ensure there was no inadvertent entrapment of additional tissue before connecting the polypectomy snare to a diathermy electrosurgical unit 8 (Dyavet). A non-adhesive metal grounding plate was positioned in contact with the skin caudal to the left scapula and fixed in place using elastic adhesive bandage. The forceps were used to tense the SEC rostral as the polypectomy snare was tightened. The monopolar cutting mode (power setting 120 Watts) was then applied for approximately 60 seconds until the cyst and enclosing tissues were completely detached. No post-operative haemorrhage occurred from the remaining tissue defect ( Figure 6 ), and the site was left to heal by second intention. Gross examination confirmed complete excision of the SEC in both cases ( Figure 7 ). Dissection of the cysts revealed thick, creamy, non-odorous content enclosed within a smooth lining. Histopathology was not performed due to the pathognomonic macroscopic appearance of the cysts. Post-operative Outcome Both horses were muzzled and starved for four hours post-surgery, ensuring oral sensation had returned before food was offered. The patients were discharged later the same day with a five-day course of trimethoprim and sulfadiazine 9 (30mg/kg bwt p.o. B.I.D) and phenylbutazone 1 (2.2mg/kg bwt p.o. B.I.D). Clients were advised to feed the horses from the floor and to dampen hay for a minimum of seven to ten days to encourage mucociliary clearance and reduce airway inflammation. Repeat endoscopy was performed at four weeks post-operatively. No abnormalities were observed within the nasopharynx. A detailed assessment of the subepiglottic tissue was not performed due to the challenges of ambulatory examination. The owner of case one reported complete resolution of respiratory noise. Discussion This report describes the successful excision of SEC in two horses under standing sedation utilising a transoral polypectomy snare. The technique provides a robust method of ensnaring SECs in standing patients, thus avoiding general anaesthesia risks. . The cases in this report suggest that this technique may be suitable for patients of varying sizes. Despite a case report describing the medical management of SEC with intralesional formalin (Dougherty and Palmer, 2008), complete surgical excision remains the treatment of choice (Ducharme and Cheetham, 2019). Described techniques include sharp excision via laryngotomy or pharyngotomy (Stick and Boles, 1980, Haynes at al., 1990, Salz et al., 2013, Parente, 2015), transnasal transendoscopic laser debridement (Tulleners, 1991) and transoral excision using electrocautery (Hobo et al. 1994). Transoral or transnasal approaches are often preferred to excision via laryngotomy or pharyngotomy due to improved healing time, which is particularly pertinent in thoroughbred racehorses and animals undergoing preparation for bloodstock sales (Salz et al., 2013). Transoral and transnasal approaches described in the literature have predominantly been performed under general anaesthesia (Ahern, 2008, Ducharme and Cheetham, 2019, Salz et al, 2013, Tulleners, 1991), although a standing approach has been reported (Parente, 2015). Completing this procedure reliably without resorting to general anaesthesia presents a significant advantage (Gozalo-Marcilla et al., 2021b) in terms of risk reduction with an overall mortality rate of 0.2% (Gozalo-Marcilla et al., 2021a) compared with 0.6% (Gozalo-Marcilla et al., 2024). In oropharyngeal surgeries performed under general anaesthesia, the presence of an endotracheal tube can obscure the surgical field making access difficult, particularly in small or immature patients. Endotracheal intubation affords airway protection, facilitates controlled ventilation, allows oxygen and inhaled anaesthetic agents administration, and enables gas monitoring. However, avoidance of endotracheal intubation may be required to achieve resection of the cysts but results in a loss of both airway access and protection. These factors make standing surgery an attractive alternative in cases involving the upper airway. (Cramp et al., 2014). Transnasal laser excision done standing is described (Parente, 2015), however, the authors consider this an advanced procedure and technically challenging. Potential complications include premature cyst deflation obscuring the boundary, difficulty in maintaining visibility in horses with smaller lesions, smoke obscuring the surgical field, and the need for manipulation of the SEC during dissection and potentially provoking swallowing. Working near the epiglottis with a bare laser fibre risks iatrogenic trauma, particularly during unanticipated swallowing (Ahern and Parente, 2008); the probability is increased with longer dissection times. In the authors’ experience, extended dissection times and patient incompliance often result in conversion to general anaesthesia. The technique in this case report overcomes some of these challenges by limiting the risk of unwanted epiglottis contact by only requiring an initial positioning of the polypectomy snare and by reducing the surgical time. Excision of subepiglottic cysts transorally using a polypectomy snare has been described in horses under general anaesthesia (Hobo et al. 1994). This requires patience to ensnare the cyst successfully due to the flaccidity of the cysts and flexibility of the snare, which is passed through the biopsy channel. Digital manipulation of the SEC within the oropharynx is often necessary, which standing horses rarely tolerate irrespective of the quality of sedation or local anaesthetic technique. The time taken to excise the cyst and the difficulty in manipulating the snare make this approach impractical in the standing patient. To overcome these limitations, the polypectomy snare was modified to add rigidity to its structure by passing it through a pre-shaped infusion pipette contoured to replicate the caudal curvature of the tongue and oropharynx. Rapid ensnarement of the cyst was achieved by using the pipette to guide the wire over the body of the cyst and tighten around the base. Pre-loading the open snare through the shaft of the bronchoesophageal forceps before passing the instruments into the oropharynx allowed the cyst to be grasped and pulled rostrally, narrowing the diameter of the base prior to ensnarement. Using videoendoscopic guidance was critical in ensuring cyst ensnarement without needing to insert a hand into the oropharynx. This permitted the technique to be performed as a standing procedure and in smaller patients including the filly described. The authors consider the technique adaptable for patients less than 6-months old, provided they are of suitable temperament. To facilitate standing surgery, horses were sedated with detomidine and butorphanol followed by morphine. This protocol has been widely used within the hospital to facilitate palatal and oropharyngeal procedures, providing adequate sedation with little unwanted movement. It has been reported that butorphanol may reduce undesired tongue movements in horses undergoing oral surgery (Marley, 2014), however unpredictable sudden head movements, are recognised to occur following its administration (Clarke and Paton, 1988, Manneveau et al., 2018). Morphine, however, appears to provide analgesia in horses without this consequence (Clake and Paton, 1988) and subsequent administration may have reduced these effects in our patients. Thorough desensitisation of the soft palate is essential for passage of the custom guard and videoendoscope. Effective analgesia is reported following application of lidocaine to the larynx and pharynx but may be associated with dorsal pharyngeal collapse, limiting surgical access (Manneveau et al., 2018). The surgical field was readily accessible in both described cases but limiting the area of application may avoid such challenges in future (Manneveau et al., 2018). Perineural injection of the lingual and glossopharyngeal nerves was avoided by applying lidocaine to the tongue. The lingual nerve innervates the rostral two-thirds of the tongue; inadvertent bilateral blockade when desensitising the inferior alveolar branch of the mandibular nerve has resulted in self-trauma (Tanner and Hubbell, 2019). Successful blockade of the glossopharyngeal nerve, providing sensory innervation to the caudal third of the tongue, has only been described experimentally via an injection site within the guttural pouch (Holcombe et al, 1997). Topical application of lidocaine provided sufficient desensitisation to prevent unwanted movement as instruments were passed across the tongue in both patients described in this report. Limitations Although patient numbers are limited in this study, the authors have successfully adopted the same transoral approach to perform a variety of oropharyngeal investigations in addition to transecting epiglottic entrapments in multiple horses. Successful resection of the SECs was achieved in both cases and no perioperative complications were reported. Modification of existing surgical instruments is necessary due to a lack of suitable, commercially available equipment, which may limit the reproducibility of the described technique. Authors’ declaration of interests No conflicts of interest have been declared. Ethical animal research Two clinical cases with full owner consent for treatment. Client’s informed consent was gained. Sources of funding No institutional, private or commercial funding has been provided. Authorship The authors take sole responsibility for the conception and preparation of the manuscript. Contributed to writing of the manuscript: EW, FH and HON. Conceptualised, developed and performed the surgical technique: HON. Commented on, edited and approved final manuscript: all authors. Manufacturers’ addresses 1 Dechra, Shrewsbury, UK backend=biber, style=alphabetic, sorting=ynt ]biblatex 2 Wockhardt UK Ltd, Wrexham, UK 3 KRUUSE, Langeskov, Denmark backend=biber, style=alphabetic, sorting=ynt ]biblatex 4 Hameln Pharma Ltd, Gloucester, UK 5 Baxter Healthcare, Norfolk, Uk 6 MAI Animal Health, Melksham, UK 7 Karl Storz, Slough, Berkshire, UK backend=biber, style=alphabetic, sorting=ynt ]biblatex 8 Gima, Gessate MI, Italy 9 Vetoquinol Ltd, Towcester, UK Bibliography Ahern, B.J & Parente, E.J. (2008) Surgical Complications of the Equine Upper Respiratory Tract. Veterinary Clinics of North America. Equine Practice . 24, 465-484. Aitken, M.R. & Parente, E. J. (2011) Epiglottic abnormalities in mature non-racehorses: 23 cases (1990-2009) Journal of the American Veterinary Medical Association . 238, 1634-1638. Clarke, K. W. & Paton B. S. (1988) Combined use of detomidine with opiates in the horse. Equine Veterinary Journal . 20, 331-334. Cramp, P, A., Prange, T., Nickels, F, A. (2014) Standing Equine Surgery of the Upper Respiratory Tract. Veterinary Clinics of North America . 1, 112-140. Dougherty, S. S. & Palmer, J. L. (2008) Use of intralesional formalin administration for treatment of subepiglottic cyst in a horse. Journal of the American Veterinary Medical Association .233, 463-465. Ducharme, N.G. & Cheetham, J. (2019) Ed: Auer, J. A., Stick, J. A., Kümmerle, J. M. & Prange, T. Pharynx. Equine Surgery. Elsevier, Missouri . 5, 710-733. Gozalo-Marcilla, M., Bettschart-Wolfensberger, R., Johnston, M., Taylor, P. M. & Redond, J. I. (2021a) Data Collection for the fourth multicentre confidential enquiry into perioperative equine fatalities (CEPEF4) study: New technology and preliminary results. Animals . 11, 2549. Gozalo-Marcilla, M., & Ringer, S. K., (2021b) Recovery after general anaesthesia in adult horses: A structured summary of the literature. Animals (Basel) . 11, 1777. Gozalo-Marcilla, M.(2024) Kate Borer-Weir Memorial Lecture CEPEF – What we knew then and what we know now. Association of Anaesthetists 60 th Anniversary Meeting, Royal Society of Medicine, London, 19 th September 2024. Haynes, P. F., Beadle, R. E., McClure J. R. & Roberts, E. D. (1990) Soft palate cysts as a cause of pharyngeal dysfunction in two horses. Equine Veterinary Journal . 22, 369-371. Hobo, S. Kuwano, A., Oikawa, M., Ueyama, Y. & Nitta, M. (1994) Surgical Resection of a Subepiglottic Cyst with an Oral Flexible Endoscope in a Young Thoroughbred Horse. Journal of Equine Science . 5, 73-75. Holcolmbe, S. J., Derksen, F. J., Stick, J. A. & Robinson, N. E. (1996) Effects of bilateral hypoglossal and glossopharyngeal nerve blocks on epiglottic and soft palate position in exercising horses. Journal of the American Veterinary Medical Association . 59, 1022-1026. Manneveau, G., Lecallard, J., Thorin, C., Pamela, H. & Tessier, C. (2018) Comparison of morphological changes and tactile sensitivity of the pharynx and larynx between four standing sedative and analgesia protocols in eight adult healthy horses. Veterinary Anaethesia and Analgesia . 45, 477-486 Marley, C., Bettschart-Wolfensberger, R., Nussbaumer, P., Moine, S. & Ringer, S. K. (2014) Evaluation of romifidine constant rate infusion protocol with or without butorphanol for dentistry and opthalmologic procedures in standing horses. Veterinary Anaesthesia and Analgesia . 41, 491-497 Parente, E. (2015) Subepiglottic cysts. In: Advances in Equine Upper Respiratory Surgery, 1 st edn. Ed: Hawkins, J. F., Wiley Blackwell, Iowa. . 1, 223-226. Robertson, J. (1991) Ed: Beech J. Pharynx and Larynx. Equine Respiratory Disorders. . Lea and Febiger, Philadelphia . 1, 351-353. Salz, R. O, Acheron, B. J. & Lumsden, J. M. (2013). 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Legends Figure 1: Videoendoscopic image of the subepiglottic cyst for case 1 (SEC = Subepiglottic cyst, E = epiglottis, P = Left nasopharyngeal wall, SP = soft palate) Figure 2: Videoendoscopic image of a cluster of subepiglottic cysts for case 1 (SEC = Subepiglottic cyst, EE = Entrapped epiglottis, P = Left nasopharyngeal wall, SP = soft palate) Figure 3: A 63.5cm long 5mm diameter rigid plastic infusion pipette before (top) and after heat moulding (middle) into a shape to replicate the bronchoesophageal forceps (bottom) Figure 4: Four-wire polypectomy snare passed through the pre-shaped plastic infusion pipette with the bronchoesophageal forceps passing through the centre of the snare in preparation for grasping the SEC. Figure 5: Viewing within the oropharynx during preparation of subepiglottic cyst excision for case 1. The electrosnare has been placed around the base of the cyst. (SEC = Subepiglottic cyst, SP = soft palate, IP = Infusion pipette, BF = bronchoesophageal forceps, SN = Electrosnare) backend=biber, style=alphabetic, sorting=ynt ]biblatex Figure 6: The completely removed subepiglottic cyst for case 1 Figure 7: Viewing within the oropharynx following SEC removal for case 1. The defect in the subepiglottic tissue is readily visible (SEC defect), with a defined white margin. The soft palate (SP) is dorsally located to the epiglottis (E). Supplementary figure 1 The customised protective guard used to elevate and dorsally displace the soft palate. The endoscope has been placed through a hollow tube to minimise potential damage to the endoscope. Supplementary video 1 Endoscopic video of case one with intermittent appearance of the SEC Supplementary video 2 Endoscopic video of case two with intermittent entrapment of the epiglottis and visualisation of the SEC cluster. There is occasional intermittent dorsal displacement of the soft palate. Supplementary Material File (figure 1.docx) Download 235.31 KB File (figure 2.docx) Download 964.24 KB File (figure 3.docx) Download 240.25 KB File (figure 4.docx) Download 433.15 KB File (figure 5.docx) Download 891.22 KB File (figure 6.docx) Download 260.26 KB File (figure 7.docx) Download 353.47 KB Information & Authors Information Version history V1 Version 1 01 May 2025 Peer review timeline Published Equine Veterinary Education Version of Record 29 Oct 2025 Published Copyright This work is licensed under a Non Exclusive No Reuse License. Collection Equine Veterinary Education Keywords horse polypectomy snare standing subepiglottic cyst surgery Authors Affiliations Emily J.F. Wall 0009-0002-0927-7578 [email protected] University of Nottingham School of Veterinary Medicine and Science View all articles by this author Florence E. Hillen University of Nottingham School of Veterinary Medicine and Science View all articles by this author Henry O'Neill 0000-0002-6899-027X Donnington Grove Veterinary Group Limited View all articles by this author Metrics & Citations Metrics Article Usage 344 views 184 downloads .FvxKWukQNSOunydq8rnd { width: 100px; } Citations Download citation Emily J.F. Wall, Florence E. Hillen, Henry O'Neill. Transoral endoscopic-guided subepiglottic cyst excision in two standing horses using a polypectomy snare. Authorea . 01 May 2025. DOI: https://doi.org/10.22541/au.174609745.55127889/v1 If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download. For more information or tips please see 'Downloading to a citation manager' in the Help menu . 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