Congenital positional anomalies of the colon: radiographic diagnosis and clinical implications. II. Abnormalities of fixation

Persistent ascending mesocolon: an unexpected content in a giant and complex paraumbilical hernia of a 48-year-old obese woman

Persistent ascending mesocolon (PAM) is a rare congenital anomaly in ⁓2%-4% of individuals. PAM is associated with various complications, including volvulus of the colon and caecum, bowel perforation, intestinal obstruction, and adhesions. This case is reported on a 48-year-old woman who reported to the Ho Teaching Hospital specialist clinic with a 13-year history of initial painless and reducible paraumbilical swelling. Management was based on a surgical approach. The content of the hernia sac was unusual with a viable appendix, caecum, ascending and transverse colons inclusive, and ascending mesocolon was persistent. The repair was done through an anterior component separation technique. An onlay mesh repair was fashioned with a 30 cm × 30 cm polypropylene mesh. This case report highlights the complexities of managing a giant paraumbilical hernia in a morbidly obese patient with a PAM, a rare congenital anomaly.

Metachronous volvulus of the descending colon after resection of the sigmoid volvulus; a case report

INTRODUCTION AND IMPORTANCE

Volvulus of the large bowel is a pathological condition characterized by the twisting of the colon around itself, resulting in obstruction and potentially severe complications such as bowel ischemia and necrosis. The objective of this case report is to highlight the importance of considering volvulus as a differential diagnosis in patients with a history of colonic surgeries, particularly when presenting with symptoms indicative of bowel obstruction.

CASE PRESENTATION

The case was a 55 years old male patient who underwent Hartman procedure three years back for an indication of gangrenous sigmoid volvulus. Three months later the colostomy was reversed and descending colo-rectal end-to-end anastomosis was performed. He currently presented to the emergency department with a one day history of abdominal distension which was progressive and associated with colicky persistent abdominal pain. Exploratory laparotomy was done which showed the descending colon was massively dilated and twisted 360 degree in the counterclockwise direction. The patient was discharged from the ward after one week stay.

CLINICAL DISCUSSION

Despite of the fact that volvulus is the third most common cause of bowel obstruction, consecutive bowel obstruction secondary to volvulus at a separate time and site is an extremely rare phenomenon.

CONCLUSION

A metachronous colonic volvulus is an extremely rare clinical entity. In a patient who presents with bowel obstruction with a history of prior sigmoid colectomy. it is important to consider metachronous volvulus as differential diagnosis specially in patients with significant risk factors or residing in a geographic area known with high rates of volvulus.

A wandering spleen with 720° torsion and persistent ascending and descending mesocolon in a 5-year-old Syrian male: A case report

INTRODUCTION AND IMPORTANCE

The spleen is normally found in the left hypochondrium and it is fixed in its place by numerous suspensory ligaments. When the ligaments are elongated or abnormally developed, it causes a rare medical condition called Wandering spleen. A persistent ascending and descending mesocolon is also a congenital anomaly, resulting from the failure of fusion of the primitive dorsal mesocolon.

CASE PRESENTATION

Herein, a 5-year-old male child with sudden and acute onset of abdominal pain, constipation, nausea, tachycardia, and low urine output, imaging and blood tests revealed evidence of intestinal obstruction and normocytic anemia and neutrophilia. A laparotomy revealed persistent ascending and descending mesocolon, with a torsioned vascular pedicle of the spleen, resulting in splenomegaly and infarction. The surgeon successfully derotated the torsioned pedicle and performed a splenectomy. The patient had an uneventful postoperative course and was discharged without complications.

CLINICAL DISCUSSION

This case could be asymptomatic and the diagnosis is incidental or it could be presented with ambiguous symptoms. The differential diagnosis of WS varies according to the clinical presentation and the associated complication. For instance, in the case of WS torsion and acute presentation, the differential diagnosis is ovarian torsion, acute appendicitis, and intestinal obstruction. Currently, surgery is the only suggested treatment option even in asymptomatic patients as well.

CONCLUSION

This case of a Wandering Spleen is associated with a persistent ascending and descending mesocolon, suggesting that there may be certain risk factors. Therefore, we suggest making more research about wandering spleen in association with persistent mesocolon.

Acute abdominal pain due to sigmoid volvulus with persistent descending mesocolon: a case report

Background

Persistent descending mesocolon, an anomaly of fixation of the mesentery of the descending colon, can sometimes cause complications such as intestinal obstruction and intussusception. We present the first reported case of sigmoid volvulus with persistent descending mesocolon.

Case presentation

An 82-year-old Japanese man had intermittent lower abdominal pain. Abdominal computed tomography showed dilation and a shift to the right side of the sigmoid colon, but no findings of volvulus. The next day, he presented continuous lower abdominal pain with bloody stool. A second abdominal computed tomography showed strangulation and dilation of the sigmoid colon, with shift from the right side of the abdominal cavity to the pelvic space. This suggested the descending colon was running to the medial side with sigmoid volvulus. Emergency surgery was performed for volvulus with persistent descending mesocolon. Operative findings revealed dilation of the sigmoid colon with a partial poorly colored region and strangulation that caused volvulus. After releasing the strangulation of the sigmoid colon, the descending colon was revealed to be running more to the medial side, with adherence to small intestinal mesentery. There was no Toldt’s fusion fascia at the descending colon. Persistent descending mesocolon was therefore diagnosed due to abnormality of fixation of the descending colon. The sigmoid colon, including the poorly colored region, was resected and reconstructed, while the inferior mesenteric and left colonic arteries were preserved because of the complexity of the vascular system running around the descending and sigmoid colon due to the shortened mesentery. These findings were pathologically compatible with circulatory compromise and intestinal degeneration due to sigmoid volvulus. The patient had no complications after discharge, including in relation to defecation.

Conclusion

Persistent descending mesocolon can occasionally cause acute abdominal symptoms requiring immediate treatment. A computed tomography finding of the descending colon running more to the medial side than ordinary cases can aid diagnosis of persistent descending mesocolon.

Radiological features and clinical implications of persistent congenital mesocolon: Pictorial essay

In human foetus, the mesenteries that carry vascular and neural supply to the alimentary tube play an important role in its development and anatomical location within the abdominal cavity. The mesenteric attachments of the small bowel, transverse colon and sigmoid allow them to be intraperitoneally mobile structures. In contrast, the ascending and descending colon lose their mesenteries by fusion with the parietal peritoneum and become fixed in retroperitoneal position along the posterolateral walls of the abdomen. In about 2%-4% of individuals, this process is disrupted, causing a complete or partial retention of their congenital mesocolon. The ascending or descending colon will then remain intraperitoneally mobile, affecting the normal visceral anatomy and causing potential complications. This article reviews the spectrum of radiological manifestations and clinical consequences of these anomalies.

Persistent Descending Mesocolon as a Risk Factor of Laparoscopic Surgery for Colorectal Cancer: A Single Institution Experience

The objectives of this study are to clarify the significance of persistent descending mesocolon (PDM), a kind of intestinal malrotation, in laparoscopic colorectal surgery and present potentially useful preoperative diagnostic methods for PDM. Although several risk factors for laparoscopic colorectal surgery have been convincingly reported, the impact of PDM on laparoscopic surgery for colorectal cancer remains less studied. This was an observational study with a retrospective analysis. A consecutive 110 patients undergoing laparoscopic colorectal surgery for colorectal cancer were included. To identify risk factors for operative time of laparoscopic surgery for colorectal cancer, we examined age, sex, body mass index, American Society of Anesthesiologists Performance Status score, tumor location, depth of tumor invasion, lymph node metastasis, and PDM as potential risk factors. For identification of appropriate preoperative diagnostic imaging, we reviewed three-dimensional vessel images reconstructed from computed tomographic slice data of all patients. During the study period, no effective pre- or intraoperative diagnoses of PDM were achieved. A total of 4 patients were diagnosed with PDM. Sex (P = 0.0032); tumor location (P = 0.0044); lymph node metastasis (P = 0.022); and PDM (P = 0.0007) were identified as risk factors based on multivariate analysis. A ventrally branched left colic artery visualized by three-dimensional imaging appeared to be a highly specific feature of PDM. Laparoscopic surgery for colorectal cancer with PDM was difficult without the recognition of PDM. PDM was well-defined preoperatively using three-dimensional vessels images reconstructed from computed tomographic slice data.

Laparoscopic colectomy for persistent descending mesocolon in sigmoid colon cancer: A case report

A 55-year-old-man underwent laparoscopic sigmoidectomy for sigmoid colon cancer. Preoperative barium enema showed a slightly medial displacement of the descending colon, and the sigmoid colon was quite long. The operative findings showed that the descending colon was not fused with the retroperitoneum and shifted to the midline and the left colon adhered to the small mesentery and right pelvic wall. Thus, a diagnosis of persistent descending mesocolon (PDM) was made. The left colon, sigmoid colon, and superior rectal arteries often branch radially from the inferior mesenteric artery. The sigmoid mesentery shortens, and the inferior mesenteric vein is often close to the marginal vessels. By understanding the anatomical feature of PDM and devising surgical techniques, laparoscopic sigmoidectomy for sigmoid colon cancer with PDM could be performed without compromising its curative effect and safety.

Persistent Descending Mesocolon as a Key Risk Factor in Laparoscopic Colorectal Cancer Surgery

BACKGROUND

Persistent descending mesocolon (PDM) is a rare colonic anatomical variant. However, PDM's impact on the technical aspects and outcomes of laparoscopic colorectal cancer resection are unclear.

PATIENTS AND METHODS

This retrospective clinical cohort study was conducted at a high-volume cancer center in Japan to evaluate intra- and postoperative outcomes of laparoscopic colorectal cancer surgery in patients with (PDM+) or without (PDM-) PDM over the past 7 years.

RESULTS

Between January 2012 and September 2019, 2,775 patients underwent laparoscopic colorectal cancer resection at our center, including 60 (2.1%) cases of PDM. Preoperative detection was achieved in only 5 patients (8.3%), 39 patients were men, and 21 patients were women. The average age was 67 years. Twenty patients had a history of prior abdominal surgery (33.3%), with little or no subsequent adhesions. The average duration of sigmoidectomy in PDM+ patients (n=17; 217.7±14.2 min) was significantly longer than that in PDM- patients (n=547; 176.2±2.4 min; p=0.003), as was average blood loss (32.3±10.6 ml vs. 16.7±2.8 ml; p=0.03). Likewise, average operative time for high anterior resection in PDM+ patients (n=11; 227.1±20.2 min) was significantly longer than that in PDM- patients (n=294; 195.6±3.0 min; p=0.048). Rates of postoperative anastomotic leakage and postoperative recurrence did not differ in both groups. In PDM+ patients, retention of left colic artery had no impact on proximal specimen margins or occurrences of anastomotic leakage.

CONCLUSION

PDM prolongs operative times and increases bleeding in laparoscopic colorectal cancer surgery and should be considered a risk factor when encountered.

Volvulus of the ascending colon due to failure of zygosis: A case report and review of the literature

•

The ascending colon has been described as a retroperitoneal organ however it may occasionally have a long mesentery.

•

The process of peritoneal zygosis is incompletely understood and is subject to perturbation leading to many abnormalities.

•

The excessive mobility may predispose to volvulus of this intestinal segment.

•

There is often a long symptomatic prodrome before volvulus occurs during which the observant surgeon may intervene.

•

The mesentery has gained new relevance with respect to its role in the contemporary management of surgical diseases.

Introduction

Volvulus of the mobile ascending colon is a serious complication of a subtle embryological abnormality that frequently goes unrecognised. There has been renewed interest in the development of the mesentery because of its relevance to the contemporary management of surgical diseases. This case is presented to illustrate the dire consequences of missing this diagnosis and to review the fascinating embryology of the condition as well as its clinical implications.

Presentation of case

We report on a 23-year-old male who presented with signs and symptoms of distal small bowel obstruction after a long prior history of intermittent right lower quadrant pain. At laparotomy, a 360-degree counter-clockwise volvulus of the entire right colon was noted as the result of an excessively long ascending mesocolon and unattached hepatic flexure. All gangrenous bowel was resected with primary ileocolic anastomosis performed thereafter. The patient did well post-operatively and was subsequently discharged.

Discussion

Interruption of the in-utero events of fixation known as peritoneal zygosis lead to a persistence of the mesocolon in parts of the bowel that ordinarily are retroperitoneal. The events that lead to this anomaly are poorly understood and have been subject to controversy for centuries. New insights have challenged surgical dogma and informed new surgical techniques. Its true incidence is probably underestimated because of its indolent clinical prodrome, and it requires a high index of suspicion.

Conclusion

Failure of peritoneal zygosis is implicated in a myriad of clinical conditions. Expeditious recognition and intervention in the prodromal period can avert potentially disastrous complications.

The development of the dorsal mesentery in human embryos and fetuses

The vertebrate intestine has a continuous dorsal mesentery between pharynx and anus that facilitates intestinal mobility. Based on width and fate the dorsal mesentery can be subdivided into that of the caudal foregut, midgut, and hindgut. The dorsal mesentery of stomach and duodenum is wide and topographically complex due to strong and asymmetric growth of the stomach. The associated formation of the lesser sac partitions the dorsal mesentery into the right-sided "caval fold" that serves as conduit for the inferior caval vein and the left-sided mesogastrium. The thin dorsal mesentery of the midgut originates between the base of the superior and inferior mesenteric arteries, and follows the transient increase in intestinal growth that results in small-intestinal looping, intestinal herniation and, subsequently, return. The following fixation of a large portion of the abdominal dorsal mesentery to the dorsal peritoneal wall by adhesion and fusion is only seen in primates and is often incomplete. Adhesion and fusion of mesothelial surfaces in the lesser pelvis results in the formation of the "mesorectum". Whether Toldt's and Denonvilliers' "fasciae of fusion" identify the location of the original mesothelial surfaces or, alternatively, represent the effects of postnatal wear and tear due to intestinal motility and intra-abdominal pressure changes, remains to be shown. "Malrotations" are characterized by growth defects of the intestinal loops with an ischemic origin and a narrow mesenteric root due to insufficient adhesion and fusion.

A colovesical fistula with a persistent descending mesocolon due to partial situs inversus: A case report

•

Colovesical fistula was occered in the extremely rare condition: partial situs inversus with persistent descending mesocolon (PDM).

•

Distinctive features of PDM were shortening adhesions noted at the dorsal aspect of the descending and sigmoid mesocolon without marginal vessel.

•

In this case, these congenital abnormalities might help the suture failure during the operation of sigmoid colectomy.

Introduction

Situs inversus viscerum, a congenital condition in which the visceral organs are a mirror image of their normal physiological positions, could be total or partial. Persistent descending mesocolon (PDM) is a congenital anomaly that is asymptomatic because of its short length. PDM causing intestinal obstruction is a known clinical complication.

Presentation of case

A 74-year-old woman presented with pneumaturia and enteruria for two months, and recurrent cystitis for a month. An enhanced computed tomography (CT) showed air in the bladder along with sigmoid colonic diverticula adherent to it, suspecting a fistula. The CT also showed partial situs inversus with the common hepatic artery, and left colic artery arising abnormally from the superior mesenteric artery (SMA). Minimally invasive endoscopic closure using the over-the-scope clipping system was difficult because of thickening and scar tissue due to chronic inflammation from diverticulitis. Thus, a sigmoidectomy was performed to close the fistula. Intraoperatively, we noted an abnormally fixed descending mesocolon. An emergency reoperation was performed on the sixth postoperative day owing to an anastomotic leak. Suture failure was attributed to these congenital abnormalities due to insufficient blood flow from an absent marginal vessel and a high endocolonic pressure by adhesions. Sigmoid colon re-resection and maturation of an ileostomy was performed. The patient had no specific postoperative complications, and the ileostomy was closed after three months.

Conclusion

We report an extremely rare case of colovesical fistula due to a PDM in a patient having partial situs inversus with abnormal branches originating from the SMA.

The mesentery: structure, function, and role in disease

Systematic study of the mesentery is now possible because of clarification of its structure. Although this area of science is in an early phase, important advances have already been made and opportunities uncovered. For example, distinctive anatomical and functional features have been revealed that justify designation of the mesentery as an organ. Accordingly, the mesentery should be subjected to the same investigatory focus that is applied to other organs and systems. In this Review, we summarise the findings of scientific investigations of the mesentery so far and explore its role in human disease. We aim to provide a platform from which to direct future scientific investigation of the human mesentery in health and disease.

Intestinal interposition: the prevalence and clinical relevance of non-hepatodiaphragmatic conditions (non-Chilaiditi forms) documented by CT and review of the literature

PURPOSE

This study was done to assess the prevalence and clinical impact of non-hepatodiaphragmatic interpositions in a sample of adult patients undergoing computed tomography (CT) for a variety of medical reasons.

MATERIALS AND METHODS

From November 2008 to April 2009, two observers jointly examined the cases of intestinal interposition in 4,338 adults undergoing CT investigations. This study sought to identify not only hepatodiaphragmatic intestinal interpositions, defined as Chilaiditi, but also other forms of intestinal interposition, which we termed non-Chilaiditi. The latter were divided into five different classes on the basis of their anatomical relationships: splenorenal, retrogastric, hepatocaval, retrosplenic, and retrorenal. Moreover, a questionnaire investigating the clinical symptoms reported to be associated with Chilaiditi syndrome was given to patients exhibiting any form of intestinal interposition and to a control sample. Finally, clinical data related to the three groups were compared.

RESULTS

Of the 4,338 patients examined, 130 (3%) were found to have intestinal interposition, for a total of 143 forms: 90 Chilaiditi and 53 non-Chilaiditi. Of the latter, 30 were splenorenal, 12 retrogastric, five hepatocaval, four retrosplenic and two retrorenal. Statistical analysis showed that the Chilaiditi group suffered most symptoms (24.4%), followed by the non-Chilaiditi group (18.9%) and control cases (10.8%). Our results were validated using the χ(2) test of significance.

CONCLUSIONS

The number of non-Chilaiditi cases amounted to just over half the number of Chilaiditi cases, with the splenorenal form being by far the most frequent. Statistical analysis showed that patients with non-Chilaiditi forms of intestinal interposition had more symptoms than did controls.

Role of plain abdominal radiographs in predicting type of congenital pouch colon

BACKGROUND

Congenital pouch colon (CPC) is a rare form of high ano-rectal malformation (ARM) in which part of or the entire colon is replaced by a pouch with a fistula to the genito-urinary tract. According to the Saxena-Mathur classification CPC is divided into five types. Although plain abdominal radiographs are taken in infants with suspicion of CPC to detect large dilatation of the pouch, the determination of the type of CPC is made during surgical exploration. Since large variations in the length of normal colon are present in the various types, management strategy options can be determined only at the time of surgery.

OBJECTIVE

The aim of this study was to review abdominal radiographs of children with congenital pouch colon (CPC) and evaluate their value in determining the type of CPC prior to surgical exploration to assist pre-operative planning.

MATERIALS AND METHODS

Over a 12-year period (1995-2007), CPC was documented in 80 children (52 boys and 28 girls, age range 1 day-9 years, median 2.4 days) and retrospective analysis of plain abdominal radiographs of 77 children at the time of presentation was performed. Radiographic findings were correlated with surgical findings.

RESULTS

Of 77 children, 5 were excluded from the study since the pouch colon was perforated. The direction of the pouch apex was correlated with surgical findings to determine the CPC type (P<0.0001, Fisher exact test). Type 1 (17/18) and type 2 CPC (18/18) were characterized by a single large pouch with the apex positioned in the left hypochondrium. In type 3 CPC (2/2) the pouch apex was directed towards the right hypochondrium. In type 4 CPC the apex of the pouch was directed towards the right hypochondrium (28/33); however in 5 children it was towards the left hypochondrium. In type 5 CPC (n=1) the radiograph was inconclusive.

CONCLUSION

Plain abdominal radiographs have a predictive value in determining the type of CPC and obviating the need for an invertogram.

Assessment of risk for intra-abdominal adhesions at laparoscopy for urological tumors

PURPOSE

Abdominal wall adhesions at laparoscopy may predispose patients to access related injuries and increase the complexity of the procedure. We have observed concern from referring physicians regarding the safety of laparoscopy in patients who previously underwent surgery because of the risk of abdominal adhesions. To assess the risk of adhesions at laparoscopy a retrospective cohort study was performed.

MATERIALS AND METHODS

All patients who underwent a transperitoneal urological laparoscopic procedure in a 6-year period at our institution were included in this study. A chart review was performed to obtain demographic/surgical data and identify preoperative risk factors for adhesions, such as previous abdominal or pelvic surgery, radiation and/or intra-abdominal inflammatory disease. Operative videotapes were reviewed to determine the presence and location of adhesions. Standard statistical analyses were performed.

RESULTS

During the study period 127 patients underwent transperitoneal laparoscopy and videotapes on 82 (65%) were available for review. A total of 44 patients (54%) were identified with preoperative risk factors for adhesions (group 1), while 38 (46%) had no risk factors (group 2). The relative risk of adhesions was 1.34 (95% CI 0.89 to 2.01, p = 0.18) when risk factors were identified. There were no differences in the groups in patient age, operative time, access technique, conversion to open surgery or complications. Estimated blood loss was significantly higher in group 2, likely due to the preponderance of cytoreductive laparoscopic nephrectomy in this group.

CONCLUSIONS

There was no difference in the risk of intra-abdominal adhesions in patients with and without identifiable preoperative risk factors. Preoperative risk factors for adhesions should not contraindicate the transperitoneal laparoscopic approach for urological oncology procedures.

Retropsoas positioned bowel: incidence and clinical relevance

PURPOSE

Our goal was to assess the incidence of retropsoas positioned large or small bowel in the population and to examine factors predisposing to its formation.

METHOD

The presence of retropsoas positioned bowel was retrospectively studied in 1,852 abdominal CT examinations of 1,055 men and 797 women, 648 younger and 1,204 older than 50 years. All examinations were considered normal or demonstrated findings that were unrelated to the position of the bowel.

RESULTS

Retropsoas positioned colon (RPC) was observed in 51 (2.8%) cases for the ascending and 45 (2.3%) for the descending colon. RPC appeared more frequently in younger (< 50 years) than older patients and in individuals with decreased amount of retroperitoneal fat. Retropsoas position of small bowel loops was observed in 11 (0.6%) patients, all exhibiting paucity of retroperitoneal fat.

CONCLUSION

Because of its prevalence, retropsoas positioned bowel should be considered when performing percutaneous diskectomy or other interventional procedures in the posterior retroperitoneum.

Malrotation of the midgut: a rare complication in an adult patient

Complications caused by a congenital anomaly of the midgut usually occur in the first 4 weeks of life; later such complications are rare. We present an adult patient with extrinsic duodenal compression caused by malrotation. The embryology, symptoms and complications in the adult and the radiological diagnosis are discussed. The literature on this subject is reviewed.

Complications of endoscopic gastrostomy: pneumoperitoneum and volvulus of the colon

Pneumoperitoneum caused by percutaneous gastrostomy usually follows a benign clinical course, but led to progressive volvulus of the ileocolic segment in the patient described here. This article explains relationships between pneumoperitoneum after surgical or endoscopic procedures and volvulus involving the intraperitoneally mobile intestinal loops.