Tag Archive for: Internal hernia

1. Department of Radiology, Royal Victoria Infirmary, Newcastle upon Tyne, UK

2. Directorate of Women’s Services, Royal Victoria Infirmary, Newcastle upon Tyne, UK

Internal hernias are rare with only a handful of cases of intravesical herniation of small bowel described in the literature. We describe a case of bladder injury following abdominal hysterectomy. Presentation was delayed as small bowel had herniated into the bladder sealing the defect and preventing any urine leak. This rare complication of pelvic surgery was suspected by an excretory phase CT scan with the findings confirmed at laparotomy,after the patient re-presented with ureteric obstruction. This complication could present with signs of small bowel obstruction, small bowel ischaemia, ureteric obstruction, haematuria or urine retention.

Internal herniation occurs when a viscus, usually small bowel, herniates through a congenital or acquired defect within the peritoneal cavity. Internal hernias are a rare cause of small bowel obstruction, with a reported incidence of less than 0.9%. [1] Viscus to viscus herniation is an unusual form of internal hernia. Less than a handful of cases of small bowel herniation through silent defects in the wall of the urinary bladder have been reported in the literature, making it one of the rarest forms of internal hernia. We report a case of a female presenting with some features of small bowel obstruction and left ureteric obstruction secondary to intravesical herniation of small bowel following recent gynaecological pelvic surgery.

A 49 year old woman with a fibroid uterus underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy for symptoms of pelvic pain and pressure. A preoperative ultrasound confirmed the presence of multiple fibroids in the uterus. Intraoperatively a 16-week size uterus with relatively normal ovaries and endometriosis in the pouch of Douglas was encountered. The anterior vaginal vault was vascular, and required oversewing with cauterisation to venous bleeders. She was discharged from hospital on the third post-operative day.

She was re-admitted on the fifth postoperative day with persistent nausea, dehydration and dysuria. She was treated with intravenous antibiotics for presumed urinary tract infection. Ultrasound of her abdomen demonstrated mild left hydronephrosis and a small volume ascites in the pelvis with several loops of associated aperistaltic small bowel (Figure 1).

A subsequent CT scan of the abdomen and pelvis was performed following intravenous administration of iodinated contrast (Figure 2).

This demonstrated mild left sided hydronephrosis and hydroureter down to the pelvis. There was a thick-walled oedematous loop of small bowel in the pelvis with some surrounding fluid. The afferent and efferent loops of bowel and associated mesenteric vessels appeared to be confluent posterior to the abnormal loop of bowel raising the possibility of an internal hernia. The bladder could not be identified separately.

A delayed excretory phase CT scan was subsequently performed (Figure 3).  This demonstrated that small bowel had herniated into the bladder forming an acute angle at the site of the bladder defect. There was no demonstrable associated urine leak. Contrast had not opacified the distal left ureter.

Consequently the patient was scheduled for emergency cystoscopy and laparotomy.

Cystoscopy demonstrated a large defect in the posterior aspect of the bladder with necrotic edges; left ureteric obstruction was confirmed 2cm proximal to the ureterovesical junction. (Figure 4)

At laparotomy the loop of small bowel which herniated through the bladder was confirmed to be viable and no bowel resection was necessary; the left ureter was re-implanted, and the bladder repaired after excision of the necrotic edges.  Bilateral ureteric stents were left in place postoperatively, and were brought through the anterior abdominal wall across the bladder.

The patient had an uncomplicated recovery following the procedure.  Retrograde pyelogram via the stents ten days after the procedure showed a non-dilated left ureter and renal pelvis with no evidence of leak around the left ureteric re-implantation site. At two months follow-up she was free of symptoms and had a normal isotope renogram with good concentration and drainage bilaterally, with a functional split of left 47%: right 53%; she was discharged from the clinic at that stage.

Intraperitoneal bladder injury is a known complication of pelvic and gynaecological surgery.[2]  Traumatic and spontaneous bladder ruptures are also recognised entities. In intoxicated patients, bladder injuries can result from minor abdominal trauma with no associated bony injury.[3]  The resulting aperture in the bladder wall presents a potential risk for internal herniation of bowel. The probability of occurrence is clearly very low, with only 5 cases reported in the international literature.[4,5,6] This is most likely attributed to the usually florid presentation of bladder rupture with signs of peritonitis and haematuria.  In the rare occasion of a loop of bowel completely or partially sealing the defect minimizing urine leak, this may result in reducing or delaying of the signs of peritonitis.  If the bladder defect is small, narrow neck herniation can result with the added risk of small bowel obstruction and strangulation.

In our case, the bladder rupture was thought to be iatrogenic following recent abdominal hysterectomy. In previous reported cases, the causations for bladder injury also included alcohol-associated bladder injury and spontaneous rupture following radiotherapy. [4,5,6]

In the limited number of reported cases, patients have presented with symptoms of haematuria or inability to void. Abdominal pain was also a shared feature. Our case and the case described by Yalla et al shared some features of strangulation and small bowel obstruction.[6] We described in addition coexistence of symptoms of flank pain related to left sided distal ureteric obstruction and associated hydronephrosis. In the immediate acute phase features of internal bleeding and hypovolemia have also been reported.[5]

The diagnosis of intravesical herniation could be made on a number of modalities.[4,5,6] We advocate CT as the most useful tool; and in today’s practice it is more likely to be the first line examination in the symptomatic patient.  The likely findings are those of internal herniation, with a cluster of bowel loops or a U-shaped solitary loop. This can be associated with prominent, engorged mesenteric vessels which along with the efferent and afferent ends of the herniated loop converge to the point of herniation. If the bowel lumen was sufficiently compressed, features of small bowel obstruction could also be present.[7] If the blood supply drops below the critical threshold, radiological signs of bowel ischemia could manifest.

The diagnosis is made by delineating the relationship between the herniated lower abdominal loop of bowel and the urinary bladder. The bladder might be underfilled as in our case which adds to the diagnostic difficulties. Coexistence of urinary retention or unexplained ureteric obstruction should raise the suspicion, especially where a normal-shaped bladder can not be fully identified.

From our experience we recommend the use of delayed excretory phase CT images through the pelvis with clamping of the urinary catheter if present. This will opacify the bladder and would help identification of the acute angle between the herniated bowel and the bladder wall which is in keeping with an intravesical lesion rather than external compression. This will also help confirm the site of ureteric obstruction – if present – to be the vesicoureteric junction. Extravasation of opacified urine can also be demonstrated.

Ultrasound may also have a role in diagnosis. The interpreter should be aware of the existence of this rare complication to aid diagnosis. Our patient had an ultrasound one day prior to her CT which correctly identified the adynamic loops of small bowel surrounded by fluid. The operator then failed to identify this fluid to be intravesical.

Cystography has also successfully shown the herniated bowel as intravesical filling defects, but usually requires the aid of CT or cystoscopy to delineate the true nature of the mass lesion.[5]

All cases of diagnosed intravesical herniation will require surgical reduction and repair to eliminate the risk of bowel obstruction, strangulation and the ongoing potential risk of urine leakage with urinary peritonitis and possible fistula formation.

Intravesical herniation of bowel is a rare but recognised complication of bladder perforation. Presentation may be delayed when a small defect in the bladder is sealed by small bowel, preventing a urine leak.  Clinical suspicion should be raised in patients with haematuria, urine retention or ureteric obstruction. Excretory phase pelvic CT has been shown to be a very useful diagnostic tool.

1. Passas V, Karavias D, Grilias D, Birbas A. Computed tomography of left paraduodenal hernia. J Comput Assist Tomogr 1986 10:542–543.

2. Mathevet P, Valencia P, Cousin C, Mellier G, Dargent D. Operative injuries during vaginal hysterectomy. Euro J Obs & Gynae 2001 97(1): 71-75.

3. Festini G, Greqorutti S, Reina G, Bellis G. Isolated intraperitoneal bladder rupture in patients with alcohol intoxication and minor abdominal trauma. Ann Emerg Med 1991 20(12) 1371-1372.

4. Liegeois F, Thoumas D, Lemercier E, et al. [Spontaneous rupture of the bladder. Apropos of 2 cases with an unusual presentation]. [French] Rupture spontanee de vessie. A propos de deux cas de presentation inhabituelle Journal de Radiologie 1998 79(11):1404-6.

5. Oesterling JE; Goldman SM; Lowe FC. Intravesical herniation of small bowel after bladder perforation.  Journal of Urology 1987 138(5): 1236-8.

6. Yalla SV; Slavick H; Burros HM. Intravesical strangulation of the small bowel. An unusual complication of rupture of urinary bladder. Urology 1973 2(5): 572-3.

7. Balthazar E. CT of small-bowel obstruction. Am J Roentgenol 1994 162: 255-261.