Intestinal malrotation
Prem Puri in Newborn Surgery, 2017
Laparoscopy can be performed for diagnosis of equivocal cases of malrotation as well as for correction of the defect. The principles of the procedure are the same as the open technique. Care must be taken to correctly identify landmarks such as the duodenum and ascending colon. To gain access to the duodenum, it is useful to raise the head of the operating table and elevate the right flank. The ascending colon falls toward the left side of the abdomen. The duodenum is exposed, and Ladd’s bands are divided. After division, the bowel is examined along its length for any further causes of obstruction. Dividing the peritoneal folds broadens the root of the mesentery, and care must be taken in not injuring the superior mesenteric vein. Appendectomy is carried out either using endoloops for intracorporeal ligation or by delivering the appendix through a trocar site and excising it extra-abdominally in smaller patients.
Emergency Colectomy in Acute Colitis
Peter Sagar, Andrew G. Hill, Charles H. Knowles, Stefan Post, Willem A. Bemelman, Patricia L. Roberts, Susan Galandiuk, John R.T. Monson, Michael R.B. Keighley, Norman S. Williams in Keighley & Williams’ Surgery of the Anus, Rectum and Colon, 2019
Mobilisation of the right colon is carried out with the patient again in the Trendelenburg position. The caecum is retracted medially, and the white line of Toldt incised, extending proximally to mobilise the mesentery of the terminal ileum. The ascending colon is medialised to the hepatic flexure, taking care to avoid injury to the right ureter and duodenum. The terminal ileum is divided using an endoscopic linear stapler at the ileocaecal junction. Mesenteric division can then begin from free edge, staying close to the bowel wall along the caecum to preserve the ileocolic pedicle. The patient is repositioned in the reverse Trendelenburg position to complete mobilisation of the hepatic flexure from the direction of the lesser sac, beginning from the previous dissection plane.
Morphological Changes During Chemical Induction Of Colon Cancer
Herman Autrup, Gary M. Williams in Experimental Colon Carcinogenesis, 2019
Individual tumor cells showed a marked variation in size and shape (Figure 5) and contained pleomorphic, hyperchromatic nuclei which were generally larger than normal. The cytoplasm of some was amphophilic and homogenous, but in most it contained accumulations of PAS-positive material. In many cells of the latter type the mucus occupied most of the cytoplasm and the nucleus was eccentric, giving them a “signet ring” appearance. Mitotic cells were scattered throughout these tumors, but were harder to identify than in moderately well-differentiated adenocarcinomas because of the difficulty in distinguishing tumor from stromal cells. As in moderately well-differentiated tumors, microvilli were fewer than normal. However, the lateral cell borders in poorly differentiated lesions were relatively less convoluted and junction specializations were less frequent. Surface villi were an uncommon microscopic feature of these tumors, but the surface topography was otherwise similar to that of moderately well-differentiated tumors. The appearances of these tumors by transmission electron micropscopy has also been described recently by Nomura et al.31 These tumors are more common in the ascending colon.21,22
Difference between right-sided and left-sided colorectal cancers: from embryology to molecular subtype
Published in Expert Review of Anticancer Therapy, 2018
Seung Yoon Yang, Min Soo Cho, Nam Kyu Kim
The endodermal gut tube created by body folding during the fourth week of gestation consists of a blind-ended cranial foregut, a blind-ended caudal hindgut, and a midgut open to the yolk sac through the vitelline duct [11]. The midgut forms the distal duodenum, jejunum, ileum, cecum, ascending colon, and proximal two-thirds of the transverse colon. The hindgut forms the distal third of the transverse colon, the descending and sigmoid colon, and the upper two-thirds of the anorectal canal. Just superior to the cloacal membrane, the primitive gut tube forms an expansion called the cloaca. During the fourth to sixth weeks, a coronal urorectal septum partitions the cloaca into the urogenital sinus, which will give rise to urogenital structures, and a dorsal anorectal canal [12]. As the right and left sides of the colon derive from different embryologic origins, anatomically, the proximal colon receives its main blood supply from the superior mesenteric artery with its capillary network being multilayered. The distal colon is perfused by the inferior mesentery artery. Between these two main sources, there is a watershed area located just proximal to the splenic flexure where branches of the left branch of the middle colic artery anastomose with those of the left colic artery. This area represents the border of the embryologic midgut and hindgut. Venous drainage of the colon largely follows the arterial supply with superior and inferior mesenteric veins draining both the right and left halves of the colon.
The Function and Prognostic Significance of Cripto-1 in Colorectal Cancer
Published in Cancer Investigation, 2020
Jun Sato, Hideaki Karasawa, Takashi Suzuki, Shun Nakayama, Munetoshi Katagiri, Shimpei Maeda, Shinobu Ohnuma, Fuyuhiko Motoi, Takeshi Naitoh, Michiaki Unno
One-hundred and ninety-two colorectal cancer specimens were acquired from patients who received surgery between 2000 and 2008 at the Department of Surgery at Tohoku University Hospital, Sendai, Japan (age range: 25–93 years). Patients who underwent irradiation or chemotherapy prior to surgery, as well as patients suspected to have hereditary nonpolyposis colorectal cancer, or cancer associated with inflammatory bowel disease, were excluded. Tumor location was defined as right-side colorectal cancer if the primary tumor was located in the cecum, ascending colon, hepatic flexure, or transverse colon, and left-side colorectal cancer if the tumor site was within the splenic flexure, descending colon, sigmoid colon, or rectum. The clinical results were assessed by determining disease-free and overall survival, and the mean follow-up period was 58 months (range: 1–131 months). All specimens were fixed in 10% formalin and embedded in paraffin wax. This study was ethically approved by the Ethics Committee at Tohoku University School of Medicine (2016-1-060).
Bowel perforation in morbid obesity secondary to COVID-19 infection
Published in Baylor University Medical Center Proceedings, 2022
Allen Jacob, Sujith Puskoor, Heath Douglas White
The patient was immediately taken to the operating room. Approximately 4.5 cm of his ascending colon and 37.0 cm of his transverse colon were removed, with colostomy creation 2 days later to allow for bowel rest. Gross pathologic exam of the resected colon showed transmural defects and associated serositis/abscess, but no thrombosis was identified. Imaging of the brain revealed a left anterior cerebral artery infarct. Two days after that event, tracheostomy was performed due to failure to wean from mechanical ventilation. Serial chest x-rays revealed worsening respiratory status with findings of interval increase in multifocal pneumonia and development of acute respiratory distress syndrome. After ongoing conversations about goals of care, the patient’s family elected to transition to comfort care. At 45 days postpresentation, the patient passed away.
Related Knowledge Centers
- Anatomy
- Iliacus Muscle
- Transverse Colon
- Liver
- Gallbladder
- Large Intestine
- Loose Connective Tissue
- Ileocecal Valve
- Cecum
- Colic Flexures