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At least 19 recordsLinked to original sources
PubMed1989

The ultrasonographic "common channel" sign: a characteristic feature of malignant obstruction of the lower end of common bile duct.

We describe an ultrasonographic "common channel" sign as the characteristic sonographic feature of malignant distal common bile duct (CBD) obstruction. Of 24 patients with obstructive jaundice due to distal CBD obstruction (pancreatic carcinoma 8, periampullary cancer 5, choledocholethiasis 10, CBD stricture due to pancreatitis 1) in whom the final diagnosis was proven at laparotomy, ultrasonography revealed 11 patients to have a thin-walled distended gallbladder continuous with a dilated CBD, which was termed the "common channel" sign. In all 11 patients, the cause of obstruction of the lower end of CBD proved to be malignant (pancreatic carcinoma 6, periampullary 5). In contrast, only 2 of the other 13 patients with obstructive jaundice with distal CBD obstruction, but without the "common channel" sign, had a malignant lesion at the lower end of CBD. The positive and the negative predictive values of the common channel sign were 100% and 85%, respectively. Thus, the ultrasonographic common channel sign is a reliable and characteristic feature of distal CBD obstruction due to malignant pathology.

Cholestasis↗
PubMed1992

Endoscopic sphincterotomy in young patients with choledochal dilatation and a long common channel: a preliminary report.

An anomalous elongated pancreaticobiliary common channel encourages reflux up both the biliary tree and the pancreatic ductal system, resulting in progressive choledochal dilatation, cholangitis with ductal calculi, relapsing pancreatitis and malignant change. Transduodenal sphincteroplasty has been used to improve drainage from the abnormal channel. The use of endoscopic sphincterotomy (ES) to establish drainage and minimize the surgical risks is reported in six symptomatic patients with mild choledochal dilatation (common bile duct diameter less than 15 mm), a common channel less than 15 mm in length and a distal stenosis. This was successful in five patients, who have no further symptoms. ES failed in the only patient with an undilated common channel and this patient went on to have open surgery. We believe ES to be safe and effective in the treatment of selected cases of long common channel.

Bile Ducts↗
PubMed1990

[Common channel syndrome--2 case reports].

The common channel syndrome is a disease mostly of young girls. To demonstrate the problems of diagnosis and therapy we report on 2 cases operated on in 1987 and 1989. The long delay of several years between the onset of symptoms and the diagnosis might be shortened by improved diagnostic possibilities (Ultrasound, ERCP). In any case of hyperamylasemia or chronic pancreatitis in childhood an obstruction of the biliary tract should be excluded. The common channel syndrome can be treated by means of sphincteroplasty or a bilidigestive anastomosis.

Amylases↗
PubMed2026

Persistent cloaca without vaginal-common channel fistula: A Case series characterizing a rare phenotype.

INTRODUCTION: Persistent cloaca occurs in approximately 1 in 25,000 live births. Among patients with cloaca, the absence of a vaginal connection to the common channel represents a rare phenotype with distinct anatomic and management considerations. We describe the urologic, gynecologic, and surgical characteristics of this patient subset. METHODS: We performed a retrospective analysis of a single-institution cohort of patients with persistent cloaca managed at a quaternary-care children's hospital between 2019 and 2025. Patients were eligible if they underwent primary cloacal repair by our multidisciplinary team and met all three diagnostic criteria for absent vaginal-common channel fistula: no hydrocolpos on imaging, no identified vaginal opening on cystoscopy or cloacagram, and no visible lumen between müllerian and cloacal structures identified intraoperatively. RESULTS: Of 51 patients who underwent primary repair, 6 (12%) met criteria for absent vaginal-common channel fistula. All met criteria for VACTEGRLS association. Common channel length ranged from 1.1 to 7.0 cm and urethral length from 0.5 to 2.2 cm. Urologic anomalies were nearly universal: five patients (83%) had a solitary functional kidney and four (67%) had vesicoureteral reflux. All underwent posterior sagittal anorectoplasty (PSARP) for rectal repair with the common channel repurposed as the neourethra. Five (83%) underwent diagnostic laparoscopy during which the müllerian structures were examined but left in situ. At last follow-up (median 17.5 months, range 4-35 months), three patients (50%) had volitional voiding and three (50%) required assisted bladder emptying via vesicostomy or Mitrofanoff. CONCLUSION: Persistent cloaca without a vaginal-common channel fistula represents a rare but clinically distinct phenotype characterized by severe urologic anomalies. Recognition of this phenotype is essential for surgical planning and long-term urologic and gynecologic surveillance. Because there was no connection between the vagina and the urinary tract, delaying management of the müllerian structures did not adversely affect the urinary tract.

Humans↗
PubMed1989

Choledochal cyst: findings on cholangiopancreatography with emphasis on ectasia of the common channel.

Choledochal cyst is a congenital malformation of the biliary tree that is unusual but by no means rare. During a 13-year period, we encountered eight patients with choledochal cysts who were evaluated with cholangiopancreatography. All of our cases showed an anomalous union of the pancreatic duct and common bile duct, resulting in a long common channel. Review of cholangiopancreatograms also showed ectasia of the common channel in six of the eight patients. Mean length of the common channel, corrected for magnification, was 26 mm (normal, less than 15 mm). The mean corrected diameter of the common channel was 7 mm (normal, 3-5 mm). We conclude that ectasia of the common channel is an important additional radiographic observation in the diagnosis of choledochal cyst. This observation has not been emphasized before.

Adolescent↗
PubMed1992

Stones in a long pancreaticobiliary common channel: a rare cause of obstructive jaundice and pancreatitis.

A case of obstructive jaundice associated with acute pancreatitis is reported. The underlying cause was a dilated long pancreaticobiliary common channel impacted with stones and bile debris. There was no stone in the rest of the biliary system except for one in the lowest part of the common bile duct and the overall appearance of the stones suggested that they originated within the common channel itself. A long common channel may be an underlying cause of various pathological conditions in the pancreaticobiliary system. Early operative intervention is recommended when such a diagnosis is made.

Acute Disease↗
PubMed1991

Common channels for water and protons at apical and basolateral cell membranes of frog skin and urinary bladder epithelia. Effects of oxytocin, heavy metals, and inhibitors of H(+)-adenosine triphosphatase.

We have compared the response of proton and water transport to oxytocin treatment in isolated frog skin and urinary bladder epithelia to provide further insights into the nature of water flow and H+ flux across individual apical and basolateral cell membranes. In isolated spontaneous sodium-transporting frog skin epithelia, lowering the pH of the apical solution from 7.4 to 6.4, 5.5, or 4.5 produced a fall in pHi in principal cells which was completely blocked by amiloride (50 microM), indicating that apical Na+ channels are permeable to protons. When sodium transport was blocked by amiloride, the H+ permeability of the apical membranes of principal cells was negligible but increased dramatically after treatment with antidiuretic hormone (ADH). In the latter condition, lowering the pH of the apical solution caused a voltage-dependent intracellular acidification, accompanied by membrane depolarization, and an increase in membrane conductance and transepithelial current. These effects were inhibited by adding Hg2+ (100 microM) or dicyclohexylcarbodiimide (DCCD, 10(-5) M) to the apical bath. Net titratable H+ flux across frog skin was increased from 30 +/- 8 to 115 +/- 18 neq.h-1.cm-2 (n = 8) after oxytocin treatment (at apical pH 5.5 and serosal pH 7.4) and was completely inhibited by DCCD (10(-5) M). The basolateral membranes of the principal cells in frog skin epithelium were found to be spontaneously permeable to H+ and passive electrogenic H+ transport across this membrane was not affected by oxytocin. Lowering the pH of the basolateral bathing solution (pHb) produced an intracellular acidification and membrane depolarization (and an increase in conductance when the normal dominant K+ conductance of this membrane was abolished by Ba2+ 1 mM). These effects of low pHb were blocked by micromolar concentrations of heavy metals (Zn2+, Ni2+, Co2+, Cd2+, and Hg2+). Lowering pHb in the presence of oxytocin (50 mU/ml) produced a transepithelial current (3 microA.cm-2 at pHb 5.5) which was blocked by 100 microM of Hg2+, Zn2+, or Ni2+ at the basolateral side, and by DCCD (10(-5) M) or Hg2+ (100 microM) from the apical side. The net hydroosmotic water flux (JH2O) induced by oxytocin in frog bladder sacs was blocked by inhibitors of H(+)-adenosine triphosphatase (ATPase). Diethylstilbestrol (DES 10(-5) M), oligomycin (10(-8) M), and DCCD (10(-5) M) prevented JH2O when present in the lumen. These effects cannot be attributed to inhibition of metabolism since cyanide (10(-4) M), or 2-deoxyglucose (10(-3) M) had no effect on JH2O.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1990

Pancreaticobiliary ductal union.

The main pancreatic duct and the common bile duct open into the second part of the duodenum alone or after joining as a common channel. A common channel of greater than 15 mm (an anomalous pancreaticobiliary duct) is associated with congenital cystic dilatation of the common bile duct and carcinoma of the gall bladder. Even a long common channel (greater than or equal to 8 mm) is associated with a higher frequency of carcinoma of the gall bladder. Gall stones smaller than the common channel and a long common channel predispose to gall stone induced acute pancreatitis. Separate openings for the two ductal systems predisposes to development of gall stones and alcohol induced chronic pancreatitis. The role of ductal union has also been investigated in primary sclerosing cholangitis and biliary atresia.

Cholangitis, Sclerosing↗
PubMed1991

[Anomaly of the pancreatico-biliary junction and etiology of choledochal cysts].

The etiology of choledochal cysts isn't yet clarified unequivocably. Numerous theories have been worked out. One of them is the 1969 by Babbitt postulated "common-channel"-theory, which is based on an anomaly of the pancreaticobiliary connection. In case of a fusion of ductus choledochus and ductus pancreaticus widely before the papilla of Vater and the formation of a common channel with a minimum length of 15 mm the reflux of pancreatic secretion into the off-leading biliary ducts may occur and choledochal cysts may develop. In order to check up this hypothesis we evaluated retrospectively pictures of a direct cholangiography (ERCP, PTC and/or intraoperative cholangiography) of 26 patients suffering from type I, IV and V ectasias of the biliary ducts according to Todani. We found a common channel with an abnormal length in 8 of 12 patients suffering from extrahepatic ectasias of the biliary duct type I and IV (66%), but we didn't find it in patients with type V intrahepatic ectasias of the biliary duct. This analysis may be recognized as a reference to the truth of the Babbitt-theory.

Cholangiography↗
PubMed1989

The surgical management of persistent cloaca: results in 54 patients treated with a posterior sagittal approach.

This report describes the author's personal experience in the surgical treatment of 54 patients. The approach is called posterior sagittal ano recto vagino urethroplasty (PSARVUP). Forty patients underwent a primary procedure, and 14 a secondary operation. The anatomic variations found were multiple, integrating a wide spectrum of defects. The posterior sagittal approach proved to be a good initial approach, and permitted complete repair of the defect in 47 patients. Seven patients required a laparotomy in addition. The length of the common channel varied from 0.5 to 7 cm. Common channels longer than 3 cm usually required some technical alternative to replace the vagina. In at least 34 cases, the vagina was reconstructed primarily without any additional technical manoeuvres. Different degrees of vaginal and uterine septation were found in 25 of 50 cases. Hydrocolpos was an associated defect in 14 of 49 patients. Sixty-eight percent of the patients had an important associated urological defect. Twenty-six patients were clinically evaluated without medical management, twenty-one of whom had voluntary bowel movements by the age of 3 years, but most of them had minor episodes of soiling. Nineteen patients had a normal sacrum, and five had urinary incontinence that was successfully managed by intermittent catheterization. Seven patients had a very abnormal sacrum, and five of them had urinary incontinence. Twenty patients underwent a late postoperative vaginoscopy, 14 of whom showed an adequate introitus and vagina, whereas five had different degrees of narrowing of the introitus. Six patients had a urethrovaginal fistula. One ureter was accidentally divided and one vagina had complete ischaemic necrosis.

Adolescent↗
PubMed1976

Gallstone pancreatitis: pathophysiology.

The stools of 45 patients with proven gallstones pancreatitis were screened for gallstones. An equal number of peripheral with gallstones but without pancreatitis served as the control group. Gallstones were found in the stools of 38 of the 45 patients (84 percent) with gallstone pancreatitis and in only five (11 percent) patients of the control group. The patients with gallstone pancreatitis experienced a relief of symptoms and a decrease in the levels of serum amylase and bilirubin prior to rectal passage of the stones. Operative cholangiography revealed reflux of contrast material into the pancreatic duct of 67 percent of the patients with gallstone pancreatitis and in only 18 percent of the controls. Of the 38 patients that passed stones, 30 cholangiograms (79 percent) demonstrated a functioning common channel. it would appear that a functioning common channel is necessary for reflux and in addition favors stone passage. This study suggests that the pathophysiology of gallstone pancreatitis relates to the temporary impaction of migrating stones at the ampulla of Vater.

Acute Disease↗
PubMed1988

Charybdotoxin block of Shaker K+ channels suggests that different types of K+ channels share common structural features.

Charybdotoxin (CTX), a 37 amino acid protein isolated from the venom of L. quinquestriatus, is a high-affinity blocker of various Ca2(+)-activated K+ channels. CTX also blocks Drosophila Shaker (Sh) clone H4 transient K+ currents expressed in Xenopus oocytes with similar affinity (Kd = 3.6 nM). CTX blocks both the open and the closed states of Sh channels with no apparent change in gating behavior. In addition, the block is enhanced as the ionic strength is lowered. These properties are identical to those of CTX block of Ca(+)-activated K+ channels, and these results suggest that the external pore openings of these two functionally dissimilar K+ channels may share common structural features.

Animals↗
PubMed1985

Characteristics of angiotensin II-, K+- and ACTH-induced calcium influx in adrenal glomerulosa cells. Evidence that angiotensin II, K+, and ACTH may open a common calcium channel.

The characteristics of angiotensin II-, K+-, and adrenocorticotropin (ACTH)-induced calcium influx were studied in isolated adrenal glomerulosa cells. Basal calcium influx rate is 0.64 +/- 0.09 nmol/min/mg of protein. Addition of angiotensin II (1 nM) causes a rapid 230% increase in calcium influx rate. This angiotensin II-induced calcium influx is sustained and is rapidly reversed by angiotensin II antagonist, [Sar1,Ala8]angiotensin II. Addition of either K+ or ACTH (1 nM) causes a 340 or 160% increase, respectively, in the rate of calcium influx. The effect of either angiotensin II, K+, or ACTH on calcium influx is dependent on extracellular calcium. The apparent Km for calcium is 0.46, 0.35, and 0.32 mM, respectively. When the extracellular concentration of K+ is 2 mM, neither angiotensin II nor ACTH stimulates calcium influx. Conversely, when extracellular K+ is increased to 6 mM, both angiotensin II and ACTH cause a greater stimulation of calcium influx than at 4 mM K+. When extracellular K+ is increased to 10 mM, calcium influx is 360% of the basal influx seen at 4 mM K+, and neither angiotensin II nor ACTH further stimulates the influx rate. Nitrendipine (1 microM) blocks both angiotensin II- and K+-induced calcium influx completely. In contrast, 10 microM nitrendipine does not completely block ACTH-induced calcium influx. The calcium channel agonist, BAY K 8644, also stimulates calcium influx; 10 nM BAY K 8644 leads to a rate of calcium influx which is 185% of basal. This BAY K 8644-induced increase in calcium influx and that caused by either angiotensin II or ACTH are additive. In contrast, BAY K 8644 has more than an additive effect on the calcium influx when paired with 6 mM K+. These results suggest that angiotensin II, K+, and ACTH stimulate calcium influx via a common calcium channel but act by different mechanisms to alter its function.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1991

In vitro measurement of the length of the sphincter of Oddi.

A study to determine the length of the sphincter of Oddi was performed using 148 autopsy specimens with adjacent structures obtained from adults. The median diameter of the common bile duct was 7 mm (range 4-13 mm). The median intramural length of the sphincter measured at gross examination of 75 specimens was 14 mm (range 7-22 mm); the median length of the common channel between the common bile and pancreatic ducts was 3 mm (range 0-9 mm). Longitudinal histological preparations for microscopic examination were made of 73 specimens. The median extramural length of the sphincter was 5 mm (range 1-11 mm). No associations were found between the length of the sphincter, intramural or extramural, and the diameter of the common bile duct, age, sex, presence of stones in the gallbladder or the postcholecystectomy state, nor was there an association between the intramural and extramural length of the sphincter (p greater than 0.05).

Adult↗
PubMed1989

Tolbutamide as mimic of glucose on beta-cell electrical activity. ATP-sensitive K+ channels as common pathway for both stimuli.

It is accepted for insulin-secreting cells in culture that the closure of ATP-sensitive K+ channels causes the glucose-dependent depolarization of pancreatic beta-cells seen at subthreshold levels (less than 100 mg/dl) of glucose. The question remains for the more thoroughly studied beta-cells in freshly dissected intact islets, however, whether closure of these channels is responsible for subthreshold glucose-dependent depolarization and suprathreshold glucose-dependent regulation of membrane electrical activity. To answer this, we took advantage of the ability of tolbutamide, an orally active antidiabetic agent, to specifically inhibit ATP-sensitive K+ channels in pancreatic beta-cells to determine whether these channels are active at sub- and suprathreshold levels of glucose and whether channel closure by tolbutamide reproduces the electrophysiological effects of glucose stimulation. We recorded membrane electrical activity from freshly dissected adult mouse pancreatic islets exposed to various levels of glucose and tolbutamide. As previously found by others, tolbutamide depolarizes islet cells in the absence of glucose, but we have found that, although the depolarization can trigger Ca2+ action potentials (spikes), a glucose-dependent permissive factor may be required for the normal bursting pattern of spiking. More significantly, we found that, unlike other beta-cell stimuli, tolbutamide specifically mimics the effects of glucose stimulation on the pattern of suprathreshold electrical activity. The effects were seen with levels of tolbutamide that correspond to those required to inhibit ATP-sensitive K+ channels. These data suggest that ATP-sensitive K+ channels are active at sub- and suprathreshold levels of glucose and may be the sole pathway by which either glucose or tolbutamide depolarizes beta-cells and controls beta-cell electrical activity.

Action Potentials↗
PubMed1991

Acute pancreatitis associated with anomalous union of the pancreaticobiliary ductal system.

Between 1978 and 1989, 13 of 48 patients with anomalous union of the pancreaticobiliary ductal system (AUPBD) were diagnosed as having acute pancreatitis. We have studied the clinical, radiologic, and surgical features of these 13 patients. A transient rise in the intraductal pressure of the pancreatic duct during an episode of abdominal pain is responsible for pancreatitis in patients with AUPBD. This rise in the intraductal pressure must be due to bile reflux into the pancreatic duct when an abnormally long common channel is blocked by cholelithiasis, protein plug, or dysfunction of the sphincter of Oddi. The pancreatitis resolves when the common channel obstruction is removed, and bile and pancreatic juice flow easily into the duodenum. We believe that this phenomenon is responsible for acute relapsing pancreatitis. It is our belief that the pancreas appears almost normal during symptom-free intervals.

Acute Disease↗