Front. Med. 2013, 7(4): 517–519 DOI 10.1007/s11684-013-0300-4
CASE REPORT
Hydrocele of the canal of Nuck — an old problem revisited John Bunni (
✉)a, Mark Gillam, Ian Michael Pope
Department of General Surgery, Bristol Royal Infirmary, Bristol BS2 8HW, UK
© Higher Education Press and Springer-Verlag Berlin Heidelberg 2013
Abstract Herein the authors describe the case of a young woman presenting with a tender lump in her groin. Clinically the differential was of either a reactive lymph node or a femoral hernia. Ultrasound scan was urgently arranged and showed a cystic lesion. Surgical exploration was carried out and revealed this to be a hydrocele of the canal of Nuck. This was excised and the patient’s symptoms resolved and she was discharged home the following day. We explore the embryology, pathophysiology and management of this rare entity. Keywords
canal of Nuck; hernia; embryology
Introduction The canal of Nuck is the female equivalent to the male patent processus vaginalis. Embryologically this accompanies the gubernaculum and develops as a result of an evagination of the parietal peritoneum accompanying the round ligament through the inguinal canal at its insertion into the labia majora [1,2]. Usually the processus vaginalis obliterates within the first year of life. Failure to do so may result in either an indirect inguinal hernia, or if the processus vaginalis remains completely patent, a communicating hydrocele. Hydrocele of the canal of Nuck remains a rare occurrence. Herein the authors describe a case of hydrocele of the canal of Nuck in a young patient and the subsequent management.
versus a femoral hernia. To avoid potentially unnecessary surgical intervention an ultrasound scan was ordered urgently. This was reported as showing a 1.5 cm 1.8 cm septated fluid collection along the line of the canal of Nuck (Fig. 1). There was no discernible connection with the peritoneal cavity. Radiologically this was in keeping with a hydrocele of the canal of Nuck.
Case presentation A previously fit and well 38-year-old female presented to the acute surgical admissions unit with a one day history of a swelling in her right groin. It was associated with constant pain but no other symptoms were described. On examination there was a small irreducible tender swelling in her right groin, below and lateral to the pubic tubercle. It was soft on palpation. There were no changes to the overlying skin and no skin lesions on her legs to account for a pathological lymph node. The differential diagnosis included a reactive lymph node
Received August 12, 2013; accepted September 27, 2013 Correspondence: [email protected]
Fig. 1 Ultrasound image of hydrocele of canal of Nuck.
The patient was offered the choice of aspiration, accepting that there may be a risk of recurrence, or surgical excision. She opted for the latter. Under general anesthesia a small incision was made over the lump and upon further dissection revealed a cystic lesion distal to the superficial inguinal ring (Fig. 2). This was excised and the inguinal canal deliberately not opened so as
518
not to weaken it. The wound was closed in layers using absorbable sutures. Following surgery, the patient was pain free, eating and drinking and discharged home the following day. Histopathological examination of the specimen confirmed the suspected diagnosis.
Fig. 2 Intraoperative image of hydrocele. Superficial inguinal ring starred.
Discussion The canal of Nuck was first described by Anton Nuck in 1691 [3]. It is a pouch of peritoneum in the female which extends across the inguinal canal accompanying the round ligament. It is the female equivalent to the processus vaginalis, which in males accompanies the testes in their descent into the scrotum, following the gubernaculum. It usually obliterates within the first year of life. Failure of obliteration results in a communication of the peritoneal cavity to the labia majora. The failure may result in either an indirect inguinal hernia, or a persistent communication of fluid in the sac resulting in a hydrocele. There are three main patterns of hydroceles of the canal of Nuck depending on the degree and location of obliteration [4]. They include: (1) Obliteration of the processus vaginalis proximal to the deep ring, resulting in no communication with the peritoneal cavity, but instead resulting in an encysted hydrocele anywhere along the tract of descent, from deep ring to labia (as in our case). (2) Persistent communication with the peritoneal cavity — resulting in a congenital hydrocele and possible inguinal hernia. (3) A combination of the above, due to the deep ring compressing the hydrocele, resulting in partial communication with the peritoneal cavity and a part enclosed sac. This results in a bi-locular hour glass type of sac.
Hydrocele of the Canal of Nuck — an old problem revisited
Hydrocele of the canal of Nuck usually presents in young girls with a painless inguinal swelling. It is a rare occurrence. Clinically other commoner differentials for lumps in the groin include femoral neuromas, true or false femoral artery aneurysms, saphena varix, inguinal or femoral hernias, lymphadenopathy, as well as soft tissue lesions such as lipoma or abscess. Bartholin’s cyst and abscess should also be considered. There are a wide variety of differentials of groin pain [5]. Investigations are tailored to answer the clinical question and refine the differential. Ultrasound is a popular first line investigation, due to the superficial nature of groin lesions, lack of radiation, cost and general ease of access. One main disadvantage with sonography is that it is highly operator dependent. The ultrasound findings in hydrocele of the canal of Nuck are those of a well-defined hypoechoic or anechoic comma shaped mass [6], which can be cystic in appearance or with septations [7], as in our patient. MRI has also been used. Clearly surgical excision of the sac is the only definitive management of hydrocele. However sonographically guided aspiration of the hydrocele is an option, which can offer symptomatic relief and obviate the need for surgery, accepting that as the mesothelial cyst lining remains, so does a risk of recurrence. In this case, once radiology confirmed no communication with the inguinal canal a local excision was made and the external oblique aponeurosis was not opened, so as to not weaken the inguinal canal. We hypothesize that in this patient the persistent processus vaginalis had partially obliterated and left a small distal sac which may have become infected. In conclusion, we feel that this pathological entity, rare as it is, is easily understood through a clear understanding of the embryology and hence it is of relevance to all general surgeons and abdominal/pelvic radiologists. Despite its rarity, its presentation is common to a variety of other causes and hence must be considered in the differential diagnosis.
Acknowledgements The patient kindly gave full written permission for this report to be made including the use of ultrasound and intraoperative images. Also thanks to Dr. Joel Tay who photographed the intraoperative findings.
Compliance with ethics guidelines John Bunni, Mark Gillam, and Ian Michael Pope declare that they have no conflict of interest. All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000 (5). Informed consent was obtained from all patients for being included in the study. Additional informed consent was obtained from all patients for which identifying information is included in this article.
John Bunni et al.
519
References
4. Counseller VS, Black BM. Hydrocele of the canal of Nuck: report of seventeen cases. Ann Surg 1941; 113(4): 625–630 5. Bunni J, Teichmann D, Berstock JR. Pouch of Douglas pelvic hernia: a rare entity managed laparoscopically. Hernia 2012; 16(5): 601–603 6. Khanna PC, Ponsky T, Zagol B, Lukish JR, Markle BM. Sonographic appearance of canal of Nuck hydrocele. Pediatr Radiol 2007; 37(6): 603–606 7. Miklos JR, Karram MM, Silver E, Reid R. Ultrasound and hookwire needle placement for localization of a hydrocele of the canal of Nuck. Obstet Gynecol 1995; 85(5 Pt 2): 884–886
1. De Meulder F, Wojciechowski M, Hubens G, Ramet J. Female hydrocele of the canal of Nuck: a case report. Eur J Pediatr 2006; 165 (3): 193–194 2. Park SJ, Lee HK, Hong HS, Kim HC, Kim DH, Park JS, Shin EJ. Hydrocele of the canal of Nuck in a girl: ultrasound and MR appearance. Br J Radiol 2004; 77(915): 243–244 3. Nuck A. Adenographia curiosa et uteri foeminei anatome nova. Leiden, 1691. 130
CASE REPORT
Hydrocele of the canal of Nuck — an old problem revisited John Bunni (
✉)a, Mark Gillam, Ian Michael Pope
Department of General Surgery, Bristol Royal Infirmary, Bristol BS2 8HW, UK
© Higher Education Press and Springer-Verlag Berlin Heidelberg 2013
Abstract Herein the authors describe the case of a young woman presenting with a tender lump in her groin. Clinically the differential was of either a reactive lymph node or a femoral hernia. Ultrasound scan was urgently arranged and showed a cystic lesion. Surgical exploration was carried out and revealed this to be a hydrocele of the canal of Nuck. This was excised and the patient’s symptoms resolved and she was discharged home the following day. We explore the embryology, pathophysiology and management of this rare entity. Keywords
canal of Nuck; hernia; embryology
Introduction The canal of Nuck is the female equivalent to the male patent processus vaginalis. Embryologically this accompanies the gubernaculum and develops as a result of an evagination of the parietal peritoneum accompanying the round ligament through the inguinal canal at its insertion into the labia majora [1,2]. Usually the processus vaginalis obliterates within the first year of life. Failure to do so may result in either an indirect inguinal hernia, or if the processus vaginalis remains completely patent, a communicating hydrocele. Hydrocele of the canal of Nuck remains a rare occurrence. Herein the authors describe a case of hydrocele of the canal of Nuck in a young patient and the subsequent management.
versus a femoral hernia. To avoid potentially unnecessary surgical intervention an ultrasound scan was ordered urgently. This was reported as showing a 1.5 cm 1.8 cm septated fluid collection along the line of the canal of Nuck (Fig. 1). There was no discernible connection with the peritoneal cavity. Radiologically this was in keeping with a hydrocele of the canal of Nuck.
Case presentation A previously fit and well 38-year-old female presented to the acute surgical admissions unit with a one day history of a swelling in her right groin. It was associated with constant pain but no other symptoms were described. On examination there was a small irreducible tender swelling in her right groin, below and lateral to the pubic tubercle. It was soft on palpation. There were no changes to the overlying skin and no skin lesions on her legs to account for a pathological lymph node. The differential diagnosis included a reactive lymph node
Received August 12, 2013; accepted September 27, 2013 Correspondence: [email protected]
Fig. 1 Ultrasound image of hydrocele of canal of Nuck.
The patient was offered the choice of aspiration, accepting that there may be a risk of recurrence, or surgical excision. She opted for the latter. Under general anesthesia a small incision was made over the lump and upon further dissection revealed a cystic lesion distal to the superficial inguinal ring (Fig. 2). This was excised and the inguinal canal deliberately not opened so as
518
not to weaken it. The wound was closed in layers using absorbable sutures. Following surgery, the patient was pain free, eating and drinking and discharged home the following day. Histopathological examination of the specimen confirmed the suspected diagnosis.
Fig. 2 Intraoperative image of hydrocele. Superficial inguinal ring starred.
Discussion The canal of Nuck was first described by Anton Nuck in 1691 [3]. It is a pouch of peritoneum in the female which extends across the inguinal canal accompanying the round ligament. It is the female equivalent to the processus vaginalis, which in males accompanies the testes in their descent into the scrotum, following the gubernaculum. It usually obliterates within the first year of life. Failure of obliteration results in a communication of the peritoneal cavity to the labia majora. The failure may result in either an indirect inguinal hernia, or a persistent communication of fluid in the sac resulting in a hydrocele. There are three main patterns of hydroceles of the canal of Nuck depending on the degree and location of obliteration [4]. They include: (1) Obliteration of the processus vaginalis proximal to the deep ring, resulting in no communication with the peritoneal cavity, but instead resulting in an encysted hydrocele anywhere along the tract of descent, from deep ring to labia (as in our case). (2) Persistent communication with the peritoneal cavity — resulting in a congenital hydrocele and possible inguinal hernia. (3) A combination of the above, due to the deep ring compressing the hydrocele, resulting in partial communication with the peritoneal cavity and a part enclosed sac. This results in a bi-locular hour glass type of sac.
Hydrocele of the Canal of Nuck — an old problem revisited
Hydrocele of the canal of Nuck usually presents in young girls with a painless inguinal swelling. It is a rare occurrence. Clinically other commoner differentials for lumps in the groin include femoral neuromas, true or false femoral artery aneurysms, saphena varix, inguinal or femoral hernias, lymphadenopathy, as well as soft tissue lesions such as lipoma or abscess. Bartholin’s cyst and abscess should also be considered. There are a wide variety of differentials of groin pain [5]. Investigations are tailored to answer the clinical question and refine the differential. Ultrasound is a popular first line investigation, due to the superficial nature of groin lesions, lack of radiation, cost and general ease of access. One main disadvantage with sonography is that it is highly operator dependent. The ultrasound findings in hydrocele of the canal of Nuck are those of a well-defined hypoechoic or anechoic comma shaped mass [6], which can be cystic in appearance or with septations [7], as in our patient. MRI has also been used. Clearly surgical excision of the sac is the only definitive management of hydrocele. However sonographically guided aspiration of the hydrocele is an option, which can offer symptomatic relief and obviate the need for surgery, accepting that as the mesothelial cyst lining remains, so does a risk of recurrence. In this case, once radiology confirmed no communication with the inguinal canal a local excision was made and the external oblique aponeurosis was not opened, so as to not weaken the inguinal canal. We hypothesize that in this patient the persistent processus vaginalis had partially obliterated and left a small distal sac which may have become infected. In conclusion, we feel that this pathological entity, rare as it is, is easily understood through a clear understanding of the embryology and hence it is of relevance to all general surgeons and abdominal/pelvic radiologists. Despite its rarity, its presentation is common to a variety of other causes and hence must be considered in the differential diagnosis.
Acknowledgements The patient kindly gave full written permission for this report to be made including the use of ultrasound and intraoperative images. Also thanks to Dr. Joel Tay who photographed the intraoperative findings.
Compliance with ethics guidelines John Bunni, Mark Gillam, and Ian Michael Pope declare that they have no conflict of interest. All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000 (5). Informed consent was obtained from all patients for being included in the study. Additional informed consent was obtained from all patients for which identifying information is included in this article.
John Bunni et al.
519
References
4. Counseller VS, Black BM. Hydrocele of the canal of Nuck: report of seventeen cases. Ann Surg 1941; 113(4): 625–630 5. Bunni J, Teichmann D, Berstock JR. Pouch of Douglas pelvic hernia: a rare entity managed laparoscopically. Hernia 2012; 16(5): 601–603 6. Khanna PC, Ponsky T, Zagol B, Lukish JR, Markle BM. Sonographic appearance of canal of Nuck hydrocele. Pediatr Radiol 2007; 37(6): 603–606 7. Miklos JR, Karram MM, Silver E, Reid R. Ultrasound and hookwire needle placement for localization of a hydrocele of the canal of Nuck. Obstet Gynecol 1995; 85(5 Pt 2): 884–886
1. De Meulder F, Wojciechowski M, Hubens G, Ramet J. Female hydrocele of the canal of Nuck: a case report. Eur J Pediatr 2006; 165 (3): 193–194 2. Park SJ, Lee HK, Hong HS, Kim HC, Kim DH, Park JS, Shin EJ. Hydrocele of the canal of Nuck in a girl: ultrasound and MR appearance. Br J Radiol 2004; 77(915): 243–244 3. Nuck A. Adenographia curiosa et uteri foeminei anatome nova. Leiden, 1691. 130
