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Pancreas divisum: stenosis of the dorsally dominant pancreatic duct. A surgically correctable lesion.

Pancreas divisum is a congenital variant of pancreatic duct drainage in which the dorsal duct dominates, most likely due to the failure of the two independent pancreatic ductal systems to fuse embryologically. Although 5 to 10 percent of the population have this congenital variation, few demonstrate symptoms related to their pancreaticobiliary ductal systems. However, patients may present with symptoms referable to this system, and the diagnosis is difficult. In this series, endoscopic retrograde cholangiopancreatography with cannulation and radiographic injection of the dorsal duct demonstrated this abnormality in 30 of 32 patients, and results of morphine-prostigmine testing were positive for symptoms, chemical enzyme elevation, or both in three fourths of the patients tested, but other maneuvers were not as helpful. The surgical approach has been to perform a sphincteroplasty of both the main and accessory ampullas and to excise the gallbladder when it is present. Pathologic study of the gallbladders showed nearly all of them to have been diseased, whereas histologic study of the ampullas was not as conclusive. In general, this condition should be suspected as part of the postcholecystectomy syndrome or in patients who present with idiopathic pancreatitis and whose conditions cannot be identified by all other diagnostic methods. Preoperative screening may be carried out with noninvasive techniques such as the morphine-prostigmine test, or by use of the secretin-stimulated ultrasonographic visualization of the ductal system. The primary tool for making the diagnosis is endoscopic retrograde cholangiopancreatography. The goal of surgical treatment should be the opening of the main and accessory ducts, since this offers the best chance for long-term relief of the patient's symptoms.

Adult↗

Graves exophthalmos unrelated to extraocular muscle enlargement. Superior rectus muscle inflammation may induce venous obstruction.

Exophthalmos is the most commonly measured sign of Graves ophthalmopathy, whereas enlargement of the extraocular muscles is the principal pathologic abnormality. The purpose of this article is to explore possible etiologies of increased volume of orbital fat and of proptosis in patients with no substantially increased total extraocular muscle volume. Computed tomographic scans of the 13 orbits reviewed in this study had the following characteristics in common: a fine, reticular pattern within the orbital fat, a prominent superior ophthalmic vein, and an enlarged superior rectus muscle. Quantitative analysis revealed that superior rectus muscle volume showed a statistically significant correlation with proptosis, whereas medial, lateral, and inferior rectus muscle volumes did not correlate with proptosis. Based on anatomic considerations, the authors postulate that superior rectus muscle enlargement alone may produce reduced venous outflow from the orbit, thereby expanding the apparent orbital fat volume and producing proptosis.

Adolescent↗

[Pathology of proximal tubal occlusion--morphologic evaluation. Results following microsurgical anastomosis].

Even today, the etiology of proximal tubal occlusion is still a controversial subject. The introduction of microsurgery in gynecology has provided a method of eliminating the main symptom of proximal tubal occlusion, i.e., sterility. Pregnancy rates of 25-30% can be achieved in overall patient collectives. Accurate histologic analyses of the specimens are essential for clinicopathological classification in three prognosis groups. For stage I patients, pregnancy rates of up to 50% (patient-related) can be achieved. Postoperative counseling can thus be differentiated on the basis of the histological results. For stage III patients the pregnancy rate is unlikely to be acceptable, even after waiting for a prolonged period of time. It has not been established whether reconstructive tubal surgery or alternative therapeutic procedures (I.V.F. and E.T.) have better chances of success in stage II. Accurate histologic analysis of the surgical specimens is an essential prerequisite for individualized sterility counseling and therapy.

Constriction, Pathologic↗

[Pathology of congenital aqueductal stenosis and posthemorrhagic hydrocephalus].

The brain stem of children with congenital aqueductal stenosis or posthemorrhagic hydrocephalus were examined histologically and immunohistochemically. Congenital aqueductal stenosis occurs in various stages of CNS development, and is associated with microdysplasia and maturational abnormalities including astrogliosis, loss of neurons (tyrosine hydroxylase reactivity) and decreased myelination (myelin basic protein reactivity) in the periaqueductal gray matter. In Arnold-Chiari type II malformation there are few dysplasias, and poor development of glial and neural components in the periventricular brainstem. On the other hand, there are marked astroglial proliferation and defects of neural fibers in the periaqueductal area in children with posthemorrhagic hydrocephalus. Fibrous proliferation in aqueduct makes stenosis, and its pathogenesis seems to be caused by edema, ependymal cell desquamation, microglial proliferation and astrogliosis in parts of hemosiderin deposition. Thus, different CSF circulation disturbance and neural transmission disorder of the brainstem may develop with occurrence time, etiology or secondary complication of hydrocephalus.

Arnold-Chiari Malformation↗

Tracheobronchial obstruction in children: experience with endoscopic airway stenting.

BACKGROUND: We reviewed our experience to determine the role of endoscopic airway stents in children with tracheobronchial obstruction. METHODS: Seventeen children (10 boys and 7 girls) aged 2 months to 16 years underwent tracheobronchial stenting. Etiology of the tracheobronchial obstruction included external vascular compression (n = 9); tracheobronchial anastomotic strictures after heart-lung/lung transplantation (n = 4); airway compression by malignant mediastinal mass (n = 2), and subglottic/high tracheal stenosis after prolonged intubation with a tracheostomy in situ (n = 2). Indications for airway stenting were failure to wean from ventilator after a mean of 82.5 days (range, 2 to 210) in 8 children; and dyspnea or stridor in the remaining 9 children. RESULTS: Ten children had a total of 24 uncovered self-expanding metal stents (either Magic Wallstent or Ultraflex Microvasive) and 7 children had silicone stents (2 straight, 3 Y and 2 T tube stents). At follow-up at 1 week to 72 months (median 21), only 8 of 17 (47%) children were alive but all the deaths were secondary to the underlying pathology and not related to tracheobronchial stenting. Six of 8 ventilator-dependent children were extubated after a mean of 5.3 days (range, 2 to 11) after airway stenting. For the 9 children stented for dyspnea, mean Medical Research Council dyspnea score decreased from 3.0 to 1.6 after stenting. CONCLUSIONS: Tracheobronchial stenting in children is only rarely needed and often undertaken in dire circumstances. The procedure has led to significant symptomatic benefit in dyspneic children and has enabled ventilator-dependent children to be extubated. Medium-term outlook after stenting with self-expanding metal stents for vascular compression of the airway is encouraging. The long-term outcome remains uncertain, however, and is ultimately influenced by the underlying disease.

Bronchial Diseases↗

Hepatic artery embolisation with a novel radiopaque polymer causes extended liver necrosis in pigs due to occlusion of the concomitant portal vein.

BACKGROUND/AIM: In an attempt to overcome some of the problems encountered with the materials available for liver embolisation, we investigated a novel radiopaque polymer of the polyurethane family (Degra-Bloc). METHODS: Hepatic artery embolisation of one liver lobe using polyurethane was performed in 19 healthy pigs. Microcirculatory changes were assessed by laser Doppler flowmetry. Radiological and pathological examinations of the livers, hearts and lungs removed provided information about the extent and effect of the embolisation. RESULTS: None of the pigs died due to hepatic failure or toxicity of polyurethane. Microcirculation of embolised liver lobes significantly decreased from 106 (+/-15) perfusion units (PU) to 45 (+/-6) PU immediately after embolisation and further to 28 (+/-7) PU before euthanasia. At this time conventional and angiographic X-ray controls demonstrated the radiopaque casts extending up to the peripheral arteries with signs of degradation over time but without formation of collateral vessels. The main pathological findings consisted of destruction of the portal tract structures and also of large areas of liver necrosis. Polyurethane was encountered in arterioles as small as 10-20 microm, but not in liver sinusoids, hearts or lungs. CONCLUSIONS: The novel polymer called DegraBloc is a biocompatible, slowly degradable, radiopaque embolic agent. The occlusion of the arterial tree up to the smallest arteriolar diameter combined with concomitant portal vein occlusion leads to sharp segmental necrosis in pig livers without formation of significant collaterals and without systemic embolism. In the treatment of liver tumours polyurethane might provide a promising alternative to conventional embolic materials, provided that it is used with care in patients with advanced liver cirrhosis.

Animals↗

Early changes in pancreatic acinar cell calcium signaling after pancreatic duct obstruction.

Intracellular Ca(2+)-changes not only participate in important signaling pathways but have also been implicated in a number of disease states including acute pancreatitis. To investigate the underlying mechanisms in an experimental model mimicking human gallstone-induced pancreatitis, we ligated the pancreatic duct of Sprague-Dawley rats and NMRI mice for up to 6 h and studied intrapancreatic changes including the dynamics of [Ca(2+)](i) in isolated acini. In contrast to bile duct ligation, pancreatic duct obstruction induced intra-pancreatic trypsinogen activation, leukocytosis, hyperamylasemia, and pancreatic edema and increased lung myeloperoxidase activity. Although resting [Ca(2+)](i) in isolated acini rose by 45% to 205 +/- 7 nmol, the acetylcholine- and cholecystokinin (CCK)-stimulated calcium peaks as well as the amylase secretion declined, but neither the [Ca(2+)](i)-signaling pattern nor the amylase output in response to the Ca(2+)-ATPase inhibitor thapsigargin nor the secretin-stimulated amylase release were impaired by pancreatic duct ligation. On the single cell level pancreatic duct ligation reduced the percentage of cells in which submaximal secretagogue stimulation was followed by a physiological response (i.e. Ca(2+) oscillations) and increased the percentage of cells with a pathological response (i.e. peak plateau or absent Ca(2+) signal). Moreover, it reduced the frequency and amplitude of Ca(2+) oscillation as well as the capacitative Ca(2+) influx in response to secretagogue stimulation. Serum pancreatic enzyme elevation as well as trypsinogen activation was significantly reduced by pretreatment of animals with the calcium chelator BAPTA-AM. These experiments suggest that pancreatic duct obstruction rapidly changes the physiological response of the exocrine pancreas to a Ca(2+)-signaling pattern that has been associated with premature digestive enzyme activation and the onset of pancreatitis, both of which can be prevented by administration of an intracellular calcium chelator.

Adenosine Triphosphatases↗

Biliary tract disorders. Postsurgical syndromes.

Cholecystectomy with or without bile duct exploration for cholelithiasis is the most commonly performed operation on the biliary tract. Postoperative symptoms can arise from biliary disorders or extrabiliary disorders, the latter mostly unrecognized pre-existing diseases. Bile but stones are the most frequent biliary organic cause for postoperative symptoms. They can be prevented by appropriate preoperative tests. Reoperation should be considered only after conservative methods of treatment (antegrade stone extraction, endoscopic papillotomy with or without retrograde stone extraction, flushing and local medical treatment with monooctanoin) have failed or wherever the causative pathology cannot be otherwise treated. Papillotomy and choledocho-duodenostomy (side-to-side) are performed when the papilla is obstructed (by stone or stenosis). While the late results of papillotomy are good and re-stenosis is rare, choledocho-duodenostomy (side-to-side) may give rise to typical postoperative symptoms due to the choledochal blind-sack. The reported frequency of this syndrome, however, varies from author to author. If postoperative symptoms occur after choledocho/hepatico-jejunostomy (end-to-side) they mainly reflect a recurrence of the underlying disease (benign stricture, biliary tract tumour) rather than a sequel of the operation itself. The significance of postoperative biliary metabolic and functional disorders is not yet clear.

Ampulla of Vater↗

A mathematical model for blood flow through an arterial bifurcation.

By introducing the finite element technique, a study of blood flow through an arterial bifurcation is presented in this paper. The blood is represented by a modified model of thixotropic power-law fluids, for which the parametric values for blood, both in normal and pathological states, have already been established. The results for the velocity profiles, pressure and wall shear stress distributions are elucidated and discussed for normal old and diseased states. The separation and reattachment points are also located for different values of the Reynolds number and the flow behaviour index (n) of the model representing the blood. The analysis identifies low shear stress zones behind the stenosis along the outer wall and high shear stresses downstream of the apex. The increasing percentage of the stenosis and the increasing values of the Reynolds number facilitate the high shear stress zones, whereas the thixotropy of the blood depicts an inbuilt mechanism of reducing high shear stresses as well as flow reversal regions.

Algorithms↗

Urological complications in chronic inflammatory diseases of the bowel.

In advanced stages, the three most common inflammatory bowel diseases - colonic diverticulitis, Crohn's disease and ulcerative colitis - cause, in some 10% of cases, secondary urological pathology involving either bladder or ureter. Colovesical fistula is found more frequently in diverticulitis and less often in Crohn's disease, which penetrates predominantly from the ileum into the bladder. On the other hand, if uretic stenosis develops it will be caused on the right side by Crohn's disease and on the left by ulcerative colitis. Vesico-intestinal fistulae will close without sequelae after resection of the diseased bowel segment. On the other hand, retroperitoneal ureteric stenosis - despite bowel resection and ureterolysis - will often require nephrectomy if operation is not carried out early enough. Frequent re-checks with infusion excretory urography will help to prevent this. Nephrolithiasis, amyloidosis and contracted bladder are other, though less common, complications of chronic inflammatory diseases of the bowel.

Chronic Disease↗

Diagnosis of bronchopulmonary infections by quantification of microflora.

The quantification of bacteria and fungi in sputum or bronchoaspirate is of clinical value for the diagnosis of respiratory tract infections. We have developed an easy method to count the micro-organisms in patients with respiratory tract infections. This consists of the quantification of micro-organisms by subsequent streakings of a calibrated loop on agar. The correlation between microbiological quantitative data and the clinical status of patients with lower respiratory tract infections is discussed. The data seem to indicate that certain bacteria present in sputum or bronchoaspirate above a certain concentration may be responsible for lower respiratory tract infections. In patients with immunological disorders or chronic pathologies even lower concentrations of micro-organisms in bronchial secretions probably are enough to cause infections. The advantage of this counting method of the microbic species from the respiratory tract consists of their quantification: thus we can attribute an etiological role to a high concentration of the germs, while micro-organisms at low concentrations are probably contaminants. By this method isolated colonies are obtained after 12-18 hours. The bacterial quantification, by respiratory samples examination of the same patient in the following days, allows us to evaluate the efficacy of antibacterial therapy, producing a reduction of bacterial concentration.

Acquired Immunodeficiency Syndrome↗

Correlation of spectral phonoangiography and carotid angiography with gross pathology in carotid stenosis.

Spectral phonoangiography, a noninvasive method for measurement of the residual-lumen diameter of carotid stenosis by bruit analysis, was compared with x-ray angiography and direct measurement of the pathological specimen at carotid endarterectomy in 39 bifurcations from 36 patients. In six studies, the bruit was too faint to analyze. In 31 of the other 33 studies, the phonoangiogram predicted the residual-lumen diameter to within 0.5 mm of the measured value. Of the 39 contrast angiograms, 35 showed residual lumens within 0.5 mm of the value measured in the specimen, two showed lumens between 0.5 and 1 mm, and the sizes of two could not be estimated because of vessel overlap in all planes. Spectral phonoangiography and contrast angiography are both accurate methods for evaluation of carotid stenosis. Since phonoangiography is noninvasive, it may be of particular value in determining the natural history in patients with carotid bruits.

Auscultation↗

Endometrial carcinoma developing after cervical amputation: the influence of cervical stenosis on prognosis.

The clinical presentation, surgico-pathologic findings and the outcome are described of seven patients with carcinoma of the endometrium, which developed remote after cervical amputation as a treatment for cervical elongation. In six patients, cervical stenosis prevented early uterine bleeding. Four patients when diagnosed, were in advanced surgical stages of the disease (Stages II and III) and all died thereafter. Three patients with surgical Stage I, had no evidence of disease 33, 96, 151 months, after diagnosis and treatment. The role of cervical stenosis in delayed diagnosis and treatment, and therefore poor prognosis is discussed. When cervical stenosis is anticipated, periodic ultrasonographic evaluation of the endometrium is justified, in order to prevent a delay in making a diagnosis of endometrial carcinoma.

Adenocarcinoma↗

Clinical recording of pressure on the spinal cord and cauda equina. Part 2: position changes in pressure on the cauda equina in central lumbar spinal stenosis.

To define the site, degree, and dynamics of mechanical compression of the spinal nerve roots, pressure was measured in 42 patients with clinical symptoms and myelographic findings indicating central lumbar spinal stenosis. Pathological pressure on the cauda equina was found in 67% of the patients. The pressure in the region of the spinal block was high during standing and walking, and in several patients exceeded mean arterial blood pressure. The block pressure was the main mechanical factor in the central part of the spinal canal causing pain and paresis. Elevated fluid pressure caudal to the block was an additional but usually subordinate factor. In 33% of the patients, normal pressure on the cauda equina was found, and lateral compression of multiple nerve roots seemed to be the only mechanical symptom-causing factor. Clinically, these patients could not be distinguished from patients with central compression. After laminectomy with decompression of the cauda equina, the field should be inspected for lateral narrowing which, if present, should be treated.

Adult↗

[Congenital nasal pyriform aperture stenosis: a case report].

Congenital nasal pyriform aperture stenosis is a rare and poorly understood pathology. It's etiology is unknown. In cases with severe nasal airway obstruction, this anomaly may produce newborn respiratory destress similar to those seen in bilateral posterior choanal atresia. It can occur as an isolated anomaly or it can be associated with a dental anomaly, craniofacial, ophthalmological or central nervous system malformation. The diagnosis is made by physical examination. Computed tomography confirms the diagnosis. Magnetic resonance imaging of the brain and pituitary endocrine axis must be performed. In patients with severe obstruction, surgical correction is necessary. We describe the case of a 1-month-old child who needed surgical treatment with a sublabial approach for a congenital nasal pyriform aperture stenosis associated with a solitary maxillary central incisor. The follow-up (4 years) reveals normal nasal airway and facial growth.

Constriction, Pathologic↗

[Potentialities of modern clinical X-ray radiology in the differential diagnosis of tumor and other obstructive diseases of the large bowel].

The misdiagnosis rate in defining the cause of obstructive colonic disease is 8.2-24.4%. This is consistent with the fact that every 5 patients with colonic obstruction present difficulties in establishing the nature of a pathological process. The paper provides the results of analysis of clinical and X-ray symptoms in 350 patients with difficult differentially diagnosed cases of narrowing of the rectum and colon. Based on the analysis, the authors identified the basically important X-ray signs that might differentiate tumor stenoses from other obstructive diseases. They also defined the specific X-ray signs of such diseases as infiltrative cancer; extraintestinal cancer involved in the large bowel; inflammatory strictures in ulcerative colitis, diverticulosis, actinomycosis, tuberculosis, intestinal endometriosis, invagination, and other obstructive diseases. The developed differentiated diagnostic criteria could enhance the overall accuracy of X-ray study in this difficult group of patients from 72.7-80% to 93%.

Colonic Diseases↗

Magnetic resonance cholangiography features of biliary abnormalities due to cavernous transformation of the portal vein.

BACKGROUND: The aim of this retrospective and monocentric study was to describe the magnetic resonance cholangiography (MRC) features of biliary abnormalities related to extrahepatic obstruction of the portal vein (EHOPV). METHODS: From September 2001 to May 2003, MRC was performed in 10 consecutive patients who had a portal thrombosis. RESULTS: Biliary ductal pathology was demonstrated via MRC in nine patients. It consisted of stenoses, ductal narrowing or irregularities involving the common bile duct for three patients with extrahepatic portal vein thrombosis discovered a mean of 1.5 years ago, or involving both right and left intrahepatic bile ducts and common bile duct for six patients with extrahepatic portal vein thrombosis discovered a mean of 16.2 years ago. Dilation of intrahepatic bile ducts was seen for seven patients, four of them having cholestasis. For three patients with symptomatic cholestasis, direct cholangiography (DC) was performed and showed the same findings as MRC which nevertheless overestimated the degree of bile duct stenosis. CONCLUSIONS: MRC seems to constitute an accurate tool to investigate noninvasively patients with portal biliopathy.

Adult↗

Diagnostic dilemmas in biliary strictures mimicking cholangiocarcinoma.

BACKGROUND/AIMS: Bile duct strictures may be malignant or benign. In the absence of previous biliary surgery a precise preoperative diagnosis is often difficult, in particular when a tumor mass is absent in the preoperative radiologic findings. METHODOLOGY: A review of 179 patients observed between 1982 and 2001 by the same surgical team with a preoperative diagnosis of malignant stricture of the biliary tree. A surgical procedure was performed in 153 of these cases. RESULTS: The presence of a malignant stricture was confirmed by final pathologic examination in 32 of 38 cases (96%) in which a curative resection was performed. A final diagnosis of inflammatory stricture secondary to choledocholithiasis was made in 3 of the remaining 6 cases (4%), along with one case each of sclerosing cholangitis, granular cell tumor and Mirizzi's syndrome, respectively. CONCLUSIONS: Precise preoperative evaluation of biliary structures can be very difficult when a tumor mass is absent. Despite the use of invasive procedures and new techniques such as magnetic resonance cholangiopancreatography, a false-positive rate of 4% may be expected. However, whenever a malignancy is not definitely excluded, biliary strictures should be treated as a cholangiocarcinoma.

Adult↗