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At least 631 records · Page 35Linked to original sources

PubMed1994

Noninvasive imaging of the biliary tree before or after laparoscopic cholecystectomy: use of three-dimensional spiral CT cholangiography.

OBJECTIVE: The purpose of this study was to determine the feasibility of using three-dimensional spiral CT after IV administration of a cholangiographic agent for noninvasive detection of anatomic variations of the bile ducts and common bile duct stones before or after laparoscopic cholecystectomy. SUBJECTS AND METHODS: Three-dimensional spiral CT cholangiography was performed before laparoscopic cholecystectomy in 24 patients and after surgery in two patients who had recurrent symptoms. After slow infusion of 250 ml of iodipamide, spiral CT was performed. Three-dimensional images of the bile ducts and a secondary reformation through the long axis of the common bile duct were obtained. Visualization of the biliary tract was evaluated by two observers. Detection of anatomic variations and common bile duct stones was assessed in 19 patients for whom a gold standard (operative or retrograde cholangiogram) was available. RESULTS: In all 26 patients, the common bile duct and the confluence of the hepatic ducts were seen on three-dimensional spiral CT cholangiograms, and in 21 patients second- or higher-order branches were also seen. Seven patients had anatomic variations and two had common bile duct stones. These anomalies were proved by operative cholangiography in each case, except for a low junction of the cystic duct and a common bile duct stone, which were shown by retrograde cholangiography. Six of the seven anatomic variations were adequately detected with spiral CT cholangiography, as were the two cases of common bile duct stones. CONCLUSION: Three-dimensional spiral CT cholangiography is a feasible method for noninvasive detection of biliary anatomic variations and common bile duct stones before or after laparoscopic cholecystectomy.

Bile Ducts↗

PubMed2000

[Coronary venous variation in patients with portal hypertension].

OBJECTIVES: To observe the changes in the anatomic variation and the hepatofugal flow of coronary vein and to evaluate the clinical significance of these changes in patients with portal hypertension. METHODS: The anatomic variations and the retrograde flow of the coronary vein, and the portal antegrade flow and the portal pressure were observed by direct and indirect portography, direct measurement of portal pressure and Doppler sonography in 200 cirrhotic patients with portal hypertension. RESULTS: Single branch and two branches of the coronary vein were noted in 79.46% and 20.54% of the patients with portal hypertension respectively by direct portography. The sites of coronary vein arising from the portal vein, splenic vein or portosplenic junction were found in 62.33%, 27.35% or 8.07% respectively. The confluence of coronary vein and portal vein was found in most patients with variceal bleeding and recurrent bleeding after devascularization. The confluence of the coronary vein and splenic vein was observed in most patients with refractory ascites without variceal bleeding. Arterial portography demonstrated retrograde opacification of the coronary vein in 26.19% (grade II portal venous pattern), 56.64% (grade III portal venous pattern), 100% (portal thrombosis and action bleeding) 47.79% (controuing periods of bleeding), and 19.05% (refractory ascites). CONCLUSIONS: The anatomic variation of the coronary vein may be related to variceal bleeding in cirrhotic patients with portal hypertension and the retrograde opacification of the coronary vein is a significant sign of variceal bleeding.

Coronary Vessel Anomalies↗

PubMed1994

Variations in venous and segmental anatomy of the liver: two- and three-dimensional MR imaging in healthy volunteers.

OBJECTIVE: The purpose of this study was to use two- and three-dimensional analysis of thin-slice MR imaging data to study the anatomic variations in the segmental anatomy of the liver. It is important to recognize these anatomic variations in order to ensure accurate localization of hepatic lesions and preoperative delineation of resection planes. SUBJECTS AND METHODS: T1-weighted MR images of contiguous 4-mm sections were obtained in 10 healthy subjects. We measured the orientations of external and internal hepatic landmarks that indicated segmental boundaries and created three-dimensional renderings of hepatic veins, intrahepatic portal branches, liver surface, and gallbladder. RESULTS: Variations in the portal branching pattern were seen in eight of 10 subjects. Most variations occurred in the right hemiliver and consisted of the absence of a right portal trunk or the presence of accessory portal branches. The division between right anterior and right posterior segments was inclined posteriorly (average, 31.2 degrees) relative to the right hepatic vein. The landmarks indicating the position of the umbilical fissure showed marked variability. Only two of 10 subjects had three hepatic veins, with the left and middle veins sharing a common trunk. In the remaining eight subjects, nine accessory veins were present: three left, one middle, and five right. CONCLUSION: Planes of resection in liver surgery are largely determined by the precise position of tumor relative to the individual segmental anatomy. Consequently, localization of liver lesions and preoperative delineation of resection planes requires consideration of the significant anatomic variations in the segmental anatomy of the liver. These anatomic variations can be depicted on two- and three-dimensional displays of T1-weighted MR images of contiguous 4-mm sections.

Adult↗

PubMed2001

Aortic origin of right hepatic artery and superior mesenteric origin of splenic artery: two rare variations demonstrated angiographically.

Anatomical variations of the celiac trunk and superior mesenteric artery are not infrequent. Knowledge of the existing aberrations is important in planning and conducting surgical or radiological procedures. A case of right hepatic artery arising independently from the aorta supplying an hepatocellular carcinoma was identified, through which transarterial chemoembolization was successfully performed. A second case is presented with a common splenomesenteric trunk branching into the splenic and superior mesenteric arteries. These two cases represent exceptional arterial variations in the upper abdomen.

Angiography↗

PubMed2006

Thoracic duct variations may complicate the anterior spine procedures.

The aim of this study is to localize and document the anatomic features of the thoracic duct and its tributaries with special emphasis on the spinal surgery point of view. The thoracic ducts were dissected from nine formaldehyde-preserved male cadavers. The drainage patterns, diameter of the thoracic duct in upper, middle and lower thoracic segments, localization of main tributaries and morphologic features of cisterna chyli were determined. The thoracic duct was detected in all cadavers. The main tributaries were concentrated at upper thoracic (between third and fifth thoracic vertebrae) and lower thoracic segments (below the level of ninth thoracic vertebra) at the right side. However, the main lymphatic tributaries were drained into the thoracic duct only in the lower thoracic area (below the level of the tenth thoracic vertebra) at the left side. Two major anatomic variations were detected in the thoracic duct. In the first case, there were two different lymphatic drainage systems. In the second case, the thoracic duct was found as bifid at two different levels. In formaldehyde preservation, the dimensions of the soft tissues may change. For that reason, the dimensions were not discussed and they may not be a guide in surgery. Additionally, our study group is quite small. Larger series may be needed to define the anatomic variations. As a conclusion, anatomic variations of the thoracic duct are numerous and must be considered to avoid complications when doing surgery.

Aorta, Thoracic↗

PubMed2003

Anatomic variants associated with newborn circumcision complications.

OBJECTIVE: Circumcision is one of the commonly performed procedures on males in the United States, Canada, Australia, and the United Kingdom. The association of minor anatomic variations of the newborn genitalia in patients with minor circumcision complications has not been previously examined. In this study, we looked for an association between subtle genital anatomic variations and newborn circumcision complications. MATERIALS AND METHODS: Over an 18-month period, children presenting for circumcision revision were examined for minor variations in genital anatomy. Children referred for other urological problems during the same period comprised the control group. The same physician evaluated all of the children. RESULTS: During this period, 68 children were evaluated for possible circumcision complications. A confirmed complication was present in 57 infants. Patients with a minor circumcision complication were found to have a 9-fold higher incidence of a prominent suprapubic fat pad, penoscrotal webbing, or being a premature infant as compared to the control group. CONCLUSIONS: Subtle anatomic variations may be associated with a higher incidence of circumcision complications. Physicians performing newborn circumcisions should thoroughly examine the genitalia for these anatomic variations prior to the procedure in order to reduce potential complications.

Circumcision, Male↗

PubMed2003

Variations in anatomy at the suprascapular notch possibly causing suprascapular nerve entrapment: an anatomical study.

The purpose of the study was to determine anatomical variations at the suprascapular notch for better understanding of possible predisposing factors for suprascapular nerve entrapment. We dissected 32 shoulders of 16 cadavers between the ages of 39 and 74 years. We observed abnormally oriented superior fibers of the subscapularis muscle in five shoulders of the 16 cadavers, which were covering the entire anterior surface of the suprascapular notch and significantly reducing the available space for the suprascapular nerve. We also detected anterior coracoscapular ligament in six of the 32 shoulders, and calcified superior transverse scapular ligament in four of the shoulders. In this study, we classified the variations for the superior transverse scapular ligament. In conclusion, knowing the anatomical variations in detail along the course of the suprascapular nerve might be important for better understanding of location and source of the entrapment syndrome, especially for individuals who are involved in violent overhead sports activities such as volleyball and baseball. To our knowledge, close relationship of subscapularis muscle with the suprascapular nerve as a possible risk factor for suprascapular nerve entrapment has not been mentioned previously.

Adult↗

PubMed1986

Lupus band test: anatomic regional variations in discoid lupus erythematosus.

Seventy-one patients with discoid lupus erythematosus were studied for anatomic regional variations in the lupus band test. The test was positive in 82% of biopsies from the scalp, face, neck, and upper extremity. Only three out of fourteen biopsies (21%) from the trunk were positive. Discoid lupus erythematosus could be confirmed or strongly suspected in the light microscopic sections from all cases. Truncal lesions should not be selected for the lupus band test in discoid lupus erythematosus if there are other choices.

Abdomen↗

PubMed1980

Variation in falciform ligament with pheumoperitoneum.

The anatomic variation in length, thickness and course of the falciform ligament was studied on abdominal radiographs of 21 patients with pneumoperitoneum. In adults, considerable variation was found: the length ranged from 6 to 14 cm (mean 9.9 cm) and thickness from 1 to 11 mm (mean 6mm). In contrast, children displayed a uniformly thin ligament. Familiarity with anatomic variation of the falciform ligament aids prompt recognition of pneumoperitoneum in seriously ill patients.

Abdomen↗

PubMed2004

Variations of hepatic veins: helical computerized tomography experience in 100 consecutive living liver donors with emphasis on right lobe.

Anatomical variations in the venous system of liver are not a rarity. A prospective helical computerized tomography (CT) study was undertaken to determine the prevalence of surgically significant hepatic venous anatomic variations among 100 consecutive living liver donors. The studies evaluated the ramification pattern of hepatic veins, the presence of accessory hepatic veins, and of segment 5 or 8 veins (or both) draining into middle hepatic vein. These data obtained by CT influenced surgical planning. Sixty-four donors donated their right lobes and 24 donors, left lateral segments. Only one donor candidate was refused due to combined hepatic and portal venous variations accompanied by multiple bile ducts. Eleven donors were also refused due to reasons other than anatomical variations. Seventeen segment 5 and 17 segment 8 veins draining into middle hepatic vein were anastomosed to inferior vena cava in 23 (36%) of the right lobe liver transplantations. The middle hepatic vein was harvested in only one of the donors. Among the 100 cases, 47 had accessory right inferior hepatic veins, 13 of which were multiple. Twenty-two of the right lobe grafts required surgical anastomoses of these accessory hepatic veins (34%). An isolated hepatic vein anomaly or the presence of accessory hepatic veins are not contraindications to be a living liver donor candidate. However, preoperative knowledge of vascular variations alters surgical management. Helical CT is a valuable tool to delineate the hepatic venous anatomy for surgical planning in living liver donors.

Adult↗

PubMed2003

Bile duct variations in partial liver transplantations from living-related donors.

The aim of this paper was to present anatomic variations of bile ducts and their effect on the perioperative course of living-related donors in partial liver transplantations in children. Liver fragments for partial transplantation were harvested from 41 related donors. Segments II and III were harvested from 35 and segments II, III, and IV from 6 donors. During the procedure, cholangiography through cystic duct was performed revealing a normal anatomy of the bile ducts in 33 (80.5%) cases. The rest of the donors showed anatomic variations. There was only one case of complications related to the bile duct. The intraoperative diagnosis of anatomic variations allowed for safe partial liver harvesting.

Bile Ducts↗

PubMed2003

Paranasal sinus bony structures and sinus functioning during viral colds in subjects with and without a history of recurrent sinusitis.

OBJECTIVES/HYPOTHESIS: The objective was to assess the impact of ostial obstruction and anatomical variations on paranasal sinus functioning during viral colds with computed tomography (CT) in subjects with and without a history of sinusitis. STUDY DESIGN: Cross-sectional study. METHODS: Twenty-three volunteers with a history of recurrent sinusitis and 25 subjects without such history who had an early (symptoms for 2-4 d) natural cold were examined by taking viral specimens and CT scans and recording symptoms. The pathological sinus changes in the CT scans were scored, and several paranasal bony anatomical variations recorded. RESULTS: Viral origin of the cold was identified in 32 (67%) subjects, similarly in the two groups. Ostiomeatal obstruction and anatomical variations were equally frequent in the subjects with and without a sinusitis history (17 of 23 vs. 17 of 25 for ostial obstruction and 17 of 23 vs. 20 of 25 for at least one variation, respectively). However, in the case of ostiomeatal obstruction the combined CT score of ethmoidal and maxillary sinuses was significantly higher in the subjects with a sinusitis history than in those without (mean +/- SD, 3.0 +/- 0.9 vs. 2.3 +/- 1.2 [P =.05, t test]). In the sinusitis-prone subjects, several variations were associated significantly with various pathological sinus CT changes (septal deviation, horizontally situated processus uncinatus, large concha bullosa, and laterally concave concha media), whereas in the control subjects, only the presence of Haller cells was related to sphenoidal sinus disease. CONCLUSION: Ostiomeatal complex obstruction and bony anatomical variations seem to have a greater impact on the functioning of paranasal sinuses during viral colds in sinusitis-prone subjects than in subjects without a sinusitis history. These differences may be associated with the increased risk of bacterial sinusitis.

Adult↗

PubMed2005

An investigation of the origin, location and variations of the renal arteries in human fetuses and their clinical relevance.

We investigated the origin, localizations and anatomic variations of the renal artery (RA) in human fetuses with the aim of determining the distribution of these variations according to lateralization and gender. In total, 90 fetuses of spontaneous abortion (45 males, 45 females) with no congenital malformations were included to the study. The abdominal aorta and its branches were dissected after latex solution colored with red ink had been injected into the vessels from the thoracic aorta. In all, 180 RA dissections were performed bilaterally in 90 cases and the anatomic variations were photographed. Right and left RAs were found to originate from the following levels according to the columna vertebralis, respectively: 3.8% and 1.9% lower T12, 67.3% and 25.0% upper L1, 9.6% and 28.8% mid L1, 15.3% and 40.3 lower L1, 3.8% and 3.8% upper 1/3 part of L2 vertebra. The right RA originated from the lateral part and anterolateral wall of the abdominal aorta in 73.0% and 26.9% of cases while the lateral and anterolateral wall origin percentages of left RA were 90.3% and 9.6%, respectively. The origin site of the right RA from the abdominal aorta was superior to, at the same level with, and inferior to that of the left RA in 53.8%, 34.6% and 11.5% of the cases, respectively. There were no variations in 75% of the cases whereas the remaining 25% had several variation patterns. The presented morphological results are as follows: A single hilar artery in 75% of the cases, double hilar arteries in 11.1%, an inferior polar artery in 10.5%, and a superior polar artery in 3.3% of specimens studied. Anatomical variations were observed more frequently among male fetuses and on the right side. Knowledge of RA variations is important for surgeons in performing many procedures and may help to avoid clinical complications, especially, during radiological examination and/or surgical approaches in the abdominal region.

Abortion, Spontaneous↗

PubMed2006

[The clinical importance of the mandibular canal course variations].

The authors review the literature relating to anatomical variations of mandibular canals. They compare the results of their examinations with the literature data. The proportion of duplicated mandibular canal observed during macroscopic examinations of mandibles proved to be substantially higher than that revealed by X-ray pictures. The knowledge of the course of the mandibular canal and its anatomical variations is of great importance in certain oral surgical interventions, such as preprosthetic operations and the insertion of enosseal implants, and during the planning of removable dentures prepared in cases involving extensively atrophied mandibles. The authors review the possible consequences of the injury of accessory mandibular canal.

Atrophy↗

PubMed2000

Anatomy of the hepatic hilar area: the plate system.

To surgically manage hilar bile duct carcinoma successfully, it is important to be familiar with the principal anatomical variations of the biliary and vascular components of the plate system in the hepatic hilar area, because all the variations in the bile ducts and vessels occur in the plate system. The plate system consists of bile ducts and blood vessels surrounded by a sheath. There are three plates in the hilar area: the hilar plate, the cystic plate, and the umbilical plate. The bile duct and blood vessel branches penetrate the plate system and form Glisson's capsule in all segments of the liver, except for the medial segment. The right hepatic duct is usually (in 53%-72% of individuals) formed by the union of the anterior segmental duct and the posterior segmental duct in the hilar area. However, three other variations have been found in which these segmental ducts do not form the right hepatic duct. Few anatomical variations have been identified in the left hepatic duct, but confusion arises because of the variations in the medial segment ducts (B4) which join the left hepatic duct at different sites. In 35.5% of individuals they join the hepatic duct in the vicinity of the hilar confluence (type I B4 anatomy), and in 64.5% of individuals they join the left hepatic duct some distance away from the confluence (type II B4 anatomy). Because B4 is very close to the hilar confluence in type I, hilar bile duct carcinoma can easily invade B4 and, for that reason, for curative resection of hilar bile duct carcinoma, resection of S4a (the inferior part of the medial segment) should be considered along with the resection of extrahepatic bile duct and caudate lobe. Variations in the portal vein and hepatic artery are found in 16%-26% and 31%-33% of individuals, respectively. Because a considerable number of anatomical variations in the bile ducts and vessels persist in the hilar area, and the reported proportions of the different variations vary, it is necessary to have a good knowledge of the plate system and the variations in the bile ducts and blood vessels in the hilar area to perform safe and curative surgery for hilar bile duct carcinoma.

Bile Ducts↗

PubMed2000

Variations of sphenoid and related structures.

The aim of this study was to delineate the precise relationship between the sphenoid sinus and internal carotid artery and the optic nerve, as well as to assess incidence of the anatomic variations of these structures. A review of 92 paranasal sinus tomographic scans was made for anatomic variations of the sphenoid sinus and related bony and neurovascular structures. Coronal and axial tomographic sections were obtained with 2.5-mm section thickness. We assessed the protrusion of the internal carotid artery (ICA) and the optic nerve (ON) into the sphenoid sinus, bone dehiscence of these structures, and pneumatization of the anterior clinoid process (ACP) and pterygoid recess (PR), as well as the variations of the sphenoid sinus septum. The protrusion of the ICA into the sphenoid sinus was found in 24 (26.1%) patients. An ON protrusion was present in 29 (31.5%) patients. Pneumatization of the PR was encountered in 27 (29.3%) patients. There was not a statistically significant relationship between the pneumatization of the PR and ICA protrusion into the sphenoid sinus (chi2 = 0.258, p = 0.168). A significant relationship between the ACP pneumatization and protrusion of the ON into the sphenoid sinus was found (chi2= 0.481,p = 0.007). Preoperative recognition of the anatomic variations by the radiologist is beneficial for identification of the limits of dissection. This is particularly important in the sphenoid sinus area where extensive pneumatization of the skull base bones may distort the anatomic configuration. Therefore, axial and coronal CT sections should always be obtained prior to any surgery in the sphenoid sinus area.

Adolescent↗

PubMed2000

Importance of the depressor septi nasi muscle in rhinoplasty: anatomic study and clinical application.

An active depressor septi muscle can accentuate a drooping nasal tip and shorten the upper lip on animation. We have found that dissection and transposition of the depressor septi muscle during rhinoplasty can improve the tip-upper lip relationship in appropriately selected patients. Although the anatomy of the depressor septi muscle has been described, the anatomic variations of this muscle have not been previously reported. The goals of this study were two-fold: (1) to define the anatomic variations of the depressor septi muscle using 55 fresh cadaver dissections and (2) to develop a clinically applicable algorithm for modification of this muscle during rhinoplasty in those patients with a short upper lip and/or tip-upper lip imbalance. Fifty-five fresh cadavers were dissected, and the anatomic variations of the depressor septi muscle were recorded. Three variations of the depressor septi muscle were delineated: type I inserted fully into the orbicularis oris (62 percent); type II inserted into the periosteum and incompletely into the orbicularis oris (22 percent); and type III showed no, or rudimentary, depressor septi muscle (16 percent). Sixty-two patients over a 4-year period (from 1995 to 1999) were identified preoperatively with a hyperactive depressor septi diagnosed by a descending nasal tip and shortened upper lip on animation. These patients underwent dissection and transposition (not resection) of the paired depressor septi during rhinoplasty with improvement or correction of the tip-upper lip imbalance in 88 percent of cases. The anatomic study, surgical indications, rationale for the operative technique, and clinical cases are presented. Dissection and transposition of the depressor septi is a valuable adjunct to rhinoplasty in patients with a type I or II muscle variant.

Adult↗

PubMed2003

[The correlation between computed tomography findings of the paranasal sinuses and the symptoms of acute sinusitis].

OBJECTIVES: We investigated the relationship between symptoms, coronal paranasal computed tomography (CT) findings and anatomic variations in patients with acute sinusitis. PATIENTS AND METHODS: The study included 44 patients (23 females, 21 males; mean age 35 years; range 21 to 74 years) whose diagnosis was acute sinusitis by history and physical examination. A comprehensive inquiry into the symptoms was made and coronal paranasal CT scans were obtained in all the patients. Correlations were sought between symptom scores, CT scores, and anatomic variations. RESULTS: No correlations were found between anatomic variations and CT scores. Total symptom scores did not correlate with CT scores. A statistically significant correlation existed only between headache and CT scores. The most commonly affected sinuses were maxillary sinuses (73%), followed by posterior ethmoidal sinuses (60%). CONCLUSION: Our data suggest that routine CT evaluations are superfluous in acute sinusitis.

Acute Disease↗