Griffiths' point: critical anastomosis at the splenic flexure. Significance in ischemia of the colon

Ma, Mengmeng

doi:10.2214/ajr.126.1.77

Cited by 94 publications

(52 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Intriguingly, the TZ region is often located close to the "watershed area" that is considered vulnerable to ischemia. 38 Local ischemia-reperfusion selectively damages NOS neurons in laboratory animals, 39 which could also occur in the human. Whether the decrease in nNOS immunoreactivity described here was due to the actual degeneration of nNOS+ neurons or if the level of nNOS expression was reduced requires further study.…”

Section: Involvementmentioning

confidence: 99%

Molecular and Cellular Characteristics of the Colonic Pseudo-obstruction in Patients With Intractable Constipation

Suh

Myung

Kwak

et al. 2015

J Neurogastroenterol Motil

View full text Add to dashboard Cite

Background/AimsChronic intestinal pseudo-obstruction (CIPO) is a disorder characterized by recurrent symptoms suggestive of obstruction such as abdominal pain, proximal distension with extremely suppressed motility in the absence of lumen-occluding lesion, whose etiology/pathophysiology is poorly understood. In this study we investigated a functionally obstructive lesion that could underlie symptoms of CIPO. MethodsWe studied colons surgically removed from 13 patients exhibiting clinical/pathological features of pseudo-obstruction but were unresponsive to standard medical treatments. The colons were characterized morphologically, functionally and molecularly, which were compared between regions and to 28 region-matched controls obtained from colon cancer patients. ResultsThe colons with pseudo-obstruction exhibited persistent luminal distension proximally, where the smooth muscle was hypertrophied with changes in the cell phenotypes. Distinct luminal narrowing was observed near the distal end of the dilated region, close to the splenic flexure, previously referred to as the "transition zone (TZ)" between the dilated and non-dilated loops. Circular muscles from the TZ responded less to depolarization and cholinergic stimulation, which was associated with downregulation of L-type calcium channel expression. Smooth muscle contractile protein was also downregulated. Myenteric ganglia and neuronal nitric oxide synthase (nNOS) positive cells were deficient, more severely in the TZ region. Interstitial cells of Cajal was relatively less affected. 561 ConclusionsThe TZ may be the principal site of functional obstruction, leading to proximal distension and smooth muscle hypertrophy, in which partial nNOS depletion could play a key role. The neuromuscular abnormalities probably synergistically contributed to the extremely suppressed motility observed in the colonic pseudo-obstruction.(J Neurogastroenterol Motil 2015;21:560-570)

show abstract

Section: Involvementmentioning

confidence: 99%

Molecular and Cellular Characteristics of the Colonic Pseudo-obstruction in Patients With Intractable Constipation

Suh

Myung

Kwak

et al. 2015

J Neurogastroenterol Motil

View full text Add to dashboard Cite

show abstract

“…The importance of intestinal collateral blood flow in prevention of intestinal ischemia is well recognized in humans (1)(2)(3) and adult animals (4)(5)(6). Quantitative studies in adult animals have demonstrated that collateral channels among the major arterial trunks and between adjacent bowel segments both play a role in prevention of intestinal ischemia.…”

mentioning

confidence: 99%

Characterization of Intestinal Collateral Blood Flow in the Developing Piglet

Granger

1988

Pediatr Res

View full text Add to dashboard Cite

ABSTRAn. Interest in the pathogenesis of neonatal necrotizing enterocolitis has prompted study of the intestinal circulation in developing animals. It is conceivable that poorly developed collateral channels may predispose the neonatal intestine to ischemic insults. We therefore characterized intestinal collateral blood flow in anesthetized and ventilated 1-day and 1-month-old piglets. Intestinal blood flow was measured with radioactive microspheres (15 hm diameter) before and after either 1) total occlusion of the superior mesenteric artery (SMA) or 2) occlusion of a distal Cjejunoileal) branch of the SMA. After total SMA occlusion in 1-day and 1-month-old piglets, perfusion of the intestine via collaterals from the celiac and inferior mesenteric arteries was not evident. Jejunal, ileal, and colonic (except rectal) blood flows fell to zero 30 min after ligation of the SMA. Ligation of a distal branch of the SMA in 1-month-old animals significantly reduced total wall (by 25%) and mucosal/submucosal (by 25%) blood flows in the occluded segment. Similar experiments in 1-day-old piglets produced significantly greater reduction in total (70%) and mucosa/submucosa (70%) blood flows. MuscleJserosa blood flows in both groups were not significantly different from control values. In conclusion, collateral perfusion of the intestine via the celiac and inferior mesenteric arteries is insignificant during acute SMA occlusion in the developing piglet. Although there is significant collateral blood flow within the SMA vascular network, perfusion between adjacent gut segments is less effective in preventing intestinal ischemia after occlusion of a branch of the SMA in neonates than in 1-month-old piglets. (Pediatr Res 24: 473-476, 1988) Abbreviations SMA, superior mesenteric artery 46SC, scandium 46 85SR, strontium 85The importance of intestinal collateral blood flow in prevention of intestinal ischemia is well recognized in humans (1-3) and adult animals (4-6). Quantitative studies in adult animals have demonstrated that collateral channels among the major arterial trunks and between adjacent bowel segments both play a role in prevention of intestinal ischemia. In the adult cat perfusion through collateral vessels after occlusion of the superior mesenteric artery maintains flow to the small intestine and proximal colon to within 30-65% of preocclusion flow (4). However, the efficiency of collateral perfusion via the celiac and inferior mesenteric arteries is substantially lower in dogs after SMA occlusion (5). In adjacent segments of canine small bowel, collateral vessels maintain blood flow in one segment at approximately 55% of its control level when the artery to that segment is totally occluded (6).Interest in the pathogenesis of neonatal necrotizing enterocolitis in premature infants has prompted study of the intestinal circulation in developing animals. Although intestinal collateral blood flow has been extensively studied in adult animals, there are no anatomical descriptions or quantitative studies of the collatera...

show abstract

“…The other vessels have some degree of variability. Although normally a separate branch, the middle colic artery, can share a common trunk with the right colic artery (middle colic-right colic trunk (Figure 5b) in up to 52 % of cases, representing the most common variant [2][3][4]. If not involved in aberrant anatomy with the middle colic artery, the right colic artery may be an independent branch of the SMA (38%) or a branch of the ileocolic artery in 8% of cases (Figure 5c).…”

Section: Discussionmentioning

confidence: 99%

A Common Arterial Trunk Replacing Middle Colic and Right Colic Arteries: A Case Report and Surgical Significance

Aziz¹

2018

OARA

View full text Add to dashboard Cite

Introduction: The mesenteric vascular supply is a combination of rich collateral networks and commonly encountered variant anatomy. The effect of normal and variant anatomy has implications on pathology, treatment choices, and planning interventions. A review of anatomic variants will assist in understanding the implications of abnormal anatomy on treatment for diseases associated with the mesentery. Material and method:A routine dissection of mesenteric blood vessels of a 67-year old male cadaver in the dissecting room of Faculty of Medicine, Cairo University.Results: It was noted that there was a wide caliber and long (7.5cm) arterial trunk. There were absences of middle colic and right colic arteries. The middle colic artery was represented by an ascending branch while the right colic artery was represented by the descending branch. Conclusion:The incidence of such an anomaly is relatively high. These arterial variations underscore the importance of performing vascular studies prior to major abdominal surgery.

show abstract

Griffiths' point: critical anastomosis at the splenic flexure. Significance in ischemia of the colon

Cited by 94 publications

References 0 publications

Molecular and Cellular Characteristics of the Colonic Pseudo-obstruction in Patients With Intractable Constipation

Molecular and Cellular Characteristics of the Colonic Pseudo-obstruction in Patients With Intractable Constipation

Characterization of Intestinal Collateral Blood Flow in the Developing Piglet

A Common Arterial Trunk Replacing Middle Colic and Right Colic Arteries: A Case Report and Surgical Significance

Contact Info

Product

Resources

About