Robert's Uterus versus Juvenile Cystic Adenomyoma - Diagnostic and Therapeutic Challenges - Case Report and Review of Literature

A 20-year-old female presented to the outpatient department (OPD) with progressive dysmenorrhoea for the past 2 years. The lower abdominal pain affected mainly the left side started 1 day before menses and lasted for 8–10 days. She attained menarche at 13 years and had regular cycles. Initially, there was no dysmenorrhoea, but for the past 2 years, she gradually developed severe congestive dysmenorrhoea requiring parenteral analgesics. On examination, the abdomen was soft with no tenderness or palpable organomegaly. Transabdominal two-dimensional (2D) ultrasonography (USG) revealed a 3 cm × 3 cm adenomyoma present on the left side of the uterus, not communicating with the cavity. MRI revealed a left-sided uterine adenomyoma 3 cm × 3 cm anteroinferior to the left round ligament containing hypodense material [ Figure 1a ]. With a provisional diagnosis of JCA, a laparoscopic adenomyomectomy was planned. A left-sided adenomyoma was visualised intraoperatively, located anteroinferior to the left round ligament [ Figure 1b ]. During the dissection, chocolate-coloured fluid was seen coming out of the lesion. Bilateral tubes and ovaries were attached normally [ Figure 1c ]. The patient is doing well with complete resolution of symptoms for >24 months. (a) MRI picture showing JCA (marked red arrow), (b) Laparoscopic view showing JCA lesion below left round ligament, (c) Removal of the lesion followed by myometrial defect closure. Normal endometrial cavity is intact with retained both tubal attachments to the uterus, (d) MRI picture showing lesion adjacent to the endometrial cavity, (e) Laparoscopic view showing right-sided blind hemicavity (Robert's uterus), (f) Final picture after removal of the blind uterine horn, myometrial closure, and ovarian plication. JCA = Juvenile cystic adenomyoma, MRI = Magnetic resonance imaging A 13-year-old girl presented to OPD with complaints of severe progressive dysmenorrhoea since menarche. She attained menarche at the age of 11 years and had regular menstrual cycles. Following an episode of acute abdomen 1 year back, she was clinically diagnosed with acute appendicitis at a local hospital. Emergency laparotomy was performed for the presumed diagnosis of appendicitis, but the appendix was normal in appearance. However, her symptoms did not improve, and she dropped out of school due to the increasing severity of dysmenorrhoea. On examination, the abdomen was soft with no tenderness or organomegaly. Transabdominal 2D USG revealed a 4.5 cm × 3.3 cm lesion in the right uterine myometrium indenting the endometrial cavity. Bilateral ovaries were normal. MRI showed a heterogeneous lesion of size 5.4 cm × 4.5 cm in the right lateral wall of the uterus abutting the adjacent junctional zone medially, not communicating with the endometrial cavity [ Figure 1d ]. A provisional diagnosis of JCA was made, and the patient was posted for surgery. However, on laparoscopy, a bulge was noted on the right side of the uterus with the right round ligament, the fallopian tube and the ovary attached to the lesion [ Figure 1e ]. An intraoperative diagnosis of the blind uterine horn/Robert's uterus was made. Hysteroscopy revealed a tubular cavity with a single ostium seen on the left side. In view of the severe symptoms affecting her quality of life, it was decided to excise the mass completely. The incision was given at the junction of the normal uterus and lesion with utmost care to leave a thick myometrial margin. Myometrial closure was done using 1-0 V-Loc suture, and ovarian plication was done using a number 1 Vicryl suture [ Figure 1f ]. The patient had an uneventful post-operative recovery. On post-operative follow-up, the patient is doing well and has been having regular periods with no dysmenorrhoea for the last 18 months and has started going to school again.

The prevalence of congenital uterine malformations is approximately 5.5%–6.7% in the general population and higher in women with infertility and recurrent pregnancy losses.[ 1 ] Although most of the anomalies are well-researched, some anomalies are misclassified due to wide variations in clinical presentation and radiological findings. The prevalence of septate uterus in the general population is 2.3%. Robert's uterus, a rare variant of the asymmetric septate uterus, was first reported by Robert in 1970.[ 2 ] The number of cases of Robert's uterus reported in the literature are few and not well-known amongst radiologists and clinicians. The exact embryological defect in Robert's uterus is debatable with two schools of thought; segmental agenesis of the uterine isthmus with a persistent septum between upper portions of Mullerian ducts. Some authors believe it is due to unilateral cervical aplasia.[ 3 ] Cystic Mullerian anomalies have been termed as juvenile cystic adenomyoma (JCA) by Takeuchi et al . in 2010[ 4 ] and accessory cavitated uterine malformations (ACUM) by Acién et al .[ 3 ] JCA/ACUM represent Mullerian variants located at or below the level of insertion of round ligament. Although unclear, the pathophysiology is considered to be ectopia or duplication and persistence of ductal Mullerian tissue in a critical area at the level of the attachment of the round ligament.[ 5 ] The criteria proposed for diagnosing JCA include age 1 cm in diameter, independent of the uterine cavity and covered by hypertrophic myometrium, as seen on radiologic images and association with severe dysmenorrhoea.[ 4 6 ] The latest ASRM Mullerian Anomalies Classification includes Robert's uterus but does not include JCA/accessory cavitated uterine malformations (ACUMs).[ 7 ] Due to the similar clinical features of these entities, the diagnosis is complex. It may lead to inappropriate surgeries (haematometra drainage for temporary relief or complete removal of affected hemi-uterus) and adverse reproductive outcomes.[ 3 ] We present two cases of severe progressive dysmenorrhoea diagnosed as JCA on magnetic resonance imaging (MRI). One of these was found to be Robert's uterus on laparoscopy. A review of the literature, diagnostic algorithm, differentiating features of different obstructive Mullerian anomalies and various surgical options has been discussed in this article.

Diagnosis of Robert's uterus is challenging because of the rarity of the condition and lack of awareness which leads to a significant delay in diagnosis and suboptimal/overaggressive surgical interventions in most cases. Understanding the anatomical defect on MRI and selecting the best surgical procedure should be opted for in every case. Hysteroscopic metroplasty with cavity expansion needs long-term follow-up in terms of symptom relief and future reproductive performance. Informed written consent has been taken from both patients for the publication of case details. The authors certify that they have obtained all appropriate patient consent forms. In the form, the patients have given their consent for their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Nil. There are no conflicts of interest.

The present cases describe the challenges in the clinical diagnosis and management of Robert's uterus and its differentiation from other obstructuive uterine anomalies. Although MRI being the gold standard imaging modality, the misdiagnosis of Robert's uterus as JCA in the present case may be due to low awareness about both pathologies. Amongst most of Robert's uterus cases reported in the literature so far [ Table 1 ], it has been misdiagnosed as a unicornuate uterus with a non-communicating horn with haematometra due to a similar clinical presentation in most of the cases. Few cases have been misdiagnosed as JCA/ACUM as in our case,[ 13 22 23 24 ] and most of the cases have been managed as resection of blind horn either due to lack of awareness about the entity or due to severe symptoms or large lesions. The anomaly may go either unrecognised till the patient presents with some pregnancy-related complications[ 8 ] or undergo unindicated surgeries such as appendectomy as in our case.[ 17 ] Review of literature related to Robert’s uterus MTP=Medical termination of pregnancy, USG=Ultrasonography, MRI=Magnetic resonance imaging, US=Ultrasound, AVC=Automated volume calculation, HSG=Hysterosalpingography, CT=Computed tomography, JCA=Juvenile cystic adenomyoma, 2D=Two-dimensional, 3D=Three-dimensional Table 2 describes the salient differentiating features of obstructive uterine anomalies. Figure 2 illustrates the evaluation algorithm for girls presenting with severe progressive dysmenorrhoea. Surgical management is recommended for complete cure in these obstructive anomalies, and laparoscopy gives the advantage of confirmation of diagnosis and surgical therapeutic intervention in the same sitting. As described in Figure 2 , findings on imaging and laparoscopy are usually clear in cases of rudimentary functional horn, and difficulty may arise while differentiating JCA and Robert's uterus. Hysteroscopy may be combined with laparoscopy, confirming the diagnosis as a single ostium will be visualised in Robert's uterus while both ostia will be visualised in JCA. Salient features of obstructive uterine anomalies presenting with progressive dysmenorrhea JCA=Juvenile cystic adenomyoma, HSG=Hysterosalpingography, SSG=Sonosalpingography, ACUM=Accessory cavitated uterine mass, JCA=Juvenile cystic adenomyoma Evaluation algorithm and schematic diagram showing different obstructive uterine anomalies in women with progressive dysmenorrhoea The triad of Robert's uterus comprises (1) Unicornuate uterus, (2) contralateral blind hemicavity with ± haematometra and (3) normal uterine fundus ± slight external indentation [ Figure 1 ]. Three types of Robert's uterus have been described by Ludwin et al .[ 27 ] based on the functionality of the contralateral cavity and its size. In Type 1 Robert's uterus (typical Robert's uterus), hemi-uterus is fully functional and compresses on the adjacent cavity. Type 1 usually presents early in an adolescent age group with severe progressive dysmenorrhoea. Type 2 Roberts uterus has a non-functional hemi-uterus and presents relatively late with recurrent pregnancy loss or infertility and is usually diagnosed as a unicornuate uterus. Type 3 Robert's uterus has a small collection because of residual functioning endometrial tissue in the hemi-uterus. Type 3 might present in the early reproductive age group with progressive dysmenorrhoea and endometriosis. Despite this clear theoretical classification, misdiagnosis is common due to low awareness about this Mullerian anomaly.[ 28 ] Surgical options for Robert's uterus include hysteroscopic resection of the intervening septum with accompanying dilation, endometrectomy and myometrial closure and hysterectomy.[ 11 16 ] The choice of surgery for Robert's uterus depends upon age, parity, the severity of symptoms, previous obstetric history, future fertility desires, willingness for follow-up (for repeat intervention, if needed) and surgical expertise of the surgeon.[ 27 ] In cases of severe symptoms with a large adenomyotic lesion and thick muscular septum, excision of the blind hemicavity and haematometra (endometrectomy) followed by myometrial closure is appropriate.[ 28 ] Care should be taken to leave sufficient myometrial tissue to support the remaining hemi-uterus. The ipsilateral fallopian tube should be removed if the haematometra has extended to the fallopian tube and/or the tube is damaged/swollen. Hence, if it is decided for ipsilateral salpingectomy, judicious use of cautery is emphasised to avoid any thermal insult to the ovary. Hysteroscopic metroplasty has been used by some authors as a cavity expansion procedure that involves resection of the septum[ 13 15 19 20 26 29 ] under USG guidance, followed by anti-adhesiolysis therapy such as hormone replacement therapy, intrauterine contraceptive device or sequential balloon therapy.[ 14 ] Septal thickness might play a crucial role in hysteroscopic metroplasty as thick and muscular septa are difficult to cut and may cause a recurrence of symptoms. MRI and/or three-dimensional USG might help surgeons regarding septal thickness and the location of the weakest point for choosing the right approach to metroplasty. Further long-term data on follow-up are still lacking after hysteroscopic metroplasty, and its benefit in terms of cavity expansion and reproductive performance and regular follow-up is needed. Furthermore, the procedure is technically challenging, requiring surgical expertise, which might not be available in every set-up.

For the literature review, we searched PubMed and Google Scholar using the following terms: Robert's uterus, rare Mullerian anomaly and obstructive hemi-uterine anomaly. Case reports and case series of Robert's uterus were included if they met the diagnostic criteria for Robert's uterus as described by Ludwin et al .[ 14 ] Cases misreported as Robert's uterus were excluded from the study. All articles which fit into the inclusion criteria and were published till December 2021 in the English language were included in the study. Informed written consent was taken for both cases reported in the manuscript.