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At least 127 records · Page 7Linked to original sources
PubMed1999

The Posterior Interosseous Nerve Anatomical Variation and Surgical Consideration - A Case Report of Cadaver Study.

We found an anatomical variation of the posterior interosseous nerve (PIN) in a cadaver. The PIN entered the supinator muscle 3 cm distal to the radiohumeral joint, but exited from two sites. 50% of the nerve exited under the distal edge of the supinator muscle. The other half of the nerve pierced through the supinator muscle, 4.2 cm distal to the articular surface of the radial head and then joined the remaining PIN as it emerged from the supinator muscle distally. We did not find variations concerning the order and the manner of branches to the muscles. This variation in the PIN could be an additional compression site for this nerve; and therefore responsible for some of the atypical presentations of symptoms and for partial recovery after surgical decompression. A careful surgical dissection should be recommended to avoid injury to this branch.

Journal Article↗
PubMed1993

Hepatic vein reconstruction of the graft in partial liver transplantation from living donor: surgical procedures relating to their anatomic variations.

BACKGROUND: The surgical procedures to reconstruct the hepatic veins differ according to their anatomic variations to obtain the optimal graft volume for the recipient. This is an overview of the procedures used in our 25 living related liver transplantations. METHODS: The donor/recipient body weight ratio ranged widely from 1.2:1 to 9.6:1 (5.3 +/- 0.5:1, mean +/- SEM). RESULTS: The graft weight/recipient body weight was 2.40% +/- 0.21%. Graft components, which were determined by the optimal graft volume, and their drainage veins were the following: (1) segments 2 and 3 (S2+3) were used in 13 cases, 11 with the left hepatic vein (LHV) and two with the LHV and a partial drainage vein of S3; (2) S2+3 and a part of S4 in eight cases, seven with LHV and one with LHV and a partial drainage vein of S4; (3) S2+3+4 in three cases, with the common trunk of LHV and middle hepatic vein in all cases; and (4) S5+6+7+8 in one case with right hepatic vein. In two of three cases in which the graft had two drainage veins, the two vessels were reformed to have a common anastomotic orifice by the back-table plastic surgery procedure. In the other case in which the procedure could not be performed, two separate anastomoses of the individual vessels were performed successfully. Although stenosis of the reconstructed hepatic veins occurred four times in two cases at 3 months or more after transplantation, all incidences could be completely repaired by balloon dilation. CONCLUSIONS: These results show that, with careful consideration of the hepatic vein reconstruction, pediatric patients can receive optimal volume grafts from living donors.

Adolescent↗
PubMed2000

A prospective study of the anatomic variations of the median nerve in the carpal tunnel in Asians.

A prospective study of anatomic variations of the median nerve and its relationship to the surrounding structures was performed of 354 consecutive operations in 192 patients with carpal tunnel syndrome at Korea University Anam Hospital from July 1995 to September 1997. A total of 184 patients were women and 8 patients were men. A total of 162 patients were bilateral and 30 were unilateral. Regarding the course of the motor branch, the extraligamentous type was most common (96.1%, 340 patients). A total of 81.1% of patients (N = 287) had the origin of the motor branch at the radial side of the median nerve (or radial one third), and 17.2% of patients (N = 61) had the origin of the motor branch at the anterior portion of the median nerve. Of these 61 patients, 30 patients (49.1%) were of the preligamentous type. Only one motor nerve branch was found in 89.5% of patients (N = 317), and multiple branches were found in 10.5% of patients. As a result of the comparison between two hands when both hands were operated, the origin and number of motor branches and their courses were identical in most patients (>60%). Hypertrophy of the flexor pollicis brevis was found in 8.5% of patients (N = 30), hypertrophy of the palmaris brevis was found in 4.2% of patients (N = 15), absence of the palmaris longus was discovered in 0.6% of patients (N = 2), existence of the median artery was found in 0.6% of patients (N = 2), and high division of the median nerve rejoining with the thenar motor nerve was found in 0.3% of patients (N = 1). Clearly, the anatomy of the carpal tunnel in Koreans is somewhat different, in part, from the results obtained from studies of whites, but overall results are not significantly different. These results can help obtain a better surgical outcome and complete decompression of the median nerve during operation while preventing inappropriate or inadvertent injury to the motor branch of the median nerve in Koreans.

Adult↗
PubMed1976

[Anatomic variations of the common trunk of the left coronary artery (apropos of 80 dissections)].

An anatomic study of the main left coronary artery is reported : important anatomic variations may occur:--sometimes, the main left coronary artery is missing (1 % of the cases),--its origin may be unusual (from the pulmonary artery),--its average length is 11 mm; but, it may be longer (35 mm) and sometimes very short (less than 8 mm in 15 per cent of the cases) : this last aspect has to be taken in account by the surgeon during aortic valve surgery if a coronary perfusion has been decided.--At last, its division into two branches (anterior descending and left circumflex) is the most usual (65 or 70 per cent of the cases). A third branch of division may exist (diagonal or lateral branch) in about 20 to 30 per cent of the cases. The left coronary artery may also divide into four (or even five) branches in 5 to 10 per cent of the cases.

Coronary Vessel Anomalies↗
PubMedDate not supplied

[Anatomical variations of the middle cerebral artery: duplication and accessory artery. Implications in the treatment of acute stroke].

INTRODUCTION: Less than half of all subjects display a normal configuration of the Circle of Willis, according to anatomical studies. Variations of the middle cerebral artery (MCA) such as duplication or accessory MCA are infrequent but nevertheless have important clinical implications. We report the case of two patients with these variations of the MCA and their repercussions in the management of acute stroke are discussed. CASE REPORTS: Case 1: a 53 year old male with a 2 hour history of sensory motor syndrome; a transcranial Doppler (TCD) scan revealed asymmetrical speeds in the MCA. Spontaneous perforation of the MCA was suspected and we therefore decided to perform a magnetic resonance angiography scan before administering fibrinolytics. The magnetic resonance angiography scan showed an accessory MCA lying ipsilateral to the lesion. We interpreted the anomalies in blood flow detected in the TCD recording as being secondary to this anatomical variation and not due to reperfusion. Following the magnetic resonance angiography study, the possibility of fibrinolysis was ruled out. The patient recovered the neurological deficit in a matter of hours. Case 2: a 21 year old female with headaches and transient hemiparesis, who was diagnosed as suffering from migraine with aura. Later, following another stroke, it was shown that the previous clinical symptoms had been secondary to intracranial dissection with embolism in the lenticulostriate arteries and ischemic infarction in that territory. A magnetic resonance angiography scan showed duplication of the ipsilateral MCA. CONCLUSIONS: The double vascularisation of the hemisphere in cases of anatomical duplication can give rise to strokes with a better progression and prognosis, despite the occlusion of one of the MCA. The presence of anatomical variations of the MCA can lead to mistaken interpretations of the transcranial Doppler scan and may affect decision making as regards the therapy to be employed in patients with acute stroke.

Acute Disease↗
PubMed1984

Analysis of gross anatomical variations in human triploidy.

Three cases of human triploidy were dissected in detail to determine whether or not there are any specific patterns of morphologic variation associated with this form of polyploidy. No specific constellations of anatomic variation were observed. However, each body did have a greater than normal number of variations among muscles that tend to be variable in the normal population. Two bodies showed a marked increase in the size of the thigh muscles, two bodies had eyeballs that were larger than normal, and two bodies had anomalous attachments of the extraocular muscles. The sample size is not large enough to draw any specific conclusions concerning the pathogenesis of these variations. However, the findings do suggest that careful examination of additional specimens will be of value in providing further information about the genotype/phenotype relationships in human triploidy.

Abnormalities, Multiple↗
PubMed2005

Pupil decentration and iris tilting detected by Orbscan: anatomic variations among healthy subjects and influence on outcomes of laser refractive surgeries.

PURPOSE: To investigate the anatomic variations of entrance pupil decentration and tilting angle of the iris in healthy subjects and the influence of these factors on the outcome of laser in situ keratomileusis (LASIK). SETTING: Minamiaoyama Eye Clinic, Tokyo, Japan. METHODS: The degree of pupil decentration and tilting angle of the iris in 2280 eyes of 1144 myopic patients without abnormal findings by ophthalmologic examination were assessed using Orbscan. Of these, 901 eyes of 467 patients had LASIK. Multiple analysis of variance (ANOVA) was used to determine risk factors for reduction of postoperative best spectacle-corrected visual acuity (BSCVA) considering patient age, refractive power, tilting angle of the iris, pupil decentration, and corneal power. RESULTS: The mean pupil decentration in all eyes was 0.19 mm +/- 0.11 (SD) (range 0 to 0.9 mm); tilting angle of the iris was 4.06 +/- 1.41 degrees (range 0.19 to 12.69 degrees). By multiple ANOVA, refractive power, pupil decentration, and tilting angle of the iris were significant for the reduction of BSCVA. CONCLUSIONS: Some eyes with pupil decentration or tilting angle of the iris could not be detected under typical ophthalmologic examination but only with topographic examination. Attention should be paid to eyes with large pupil decentration and tilting angle of the iris because these may be risk factors for reduction of postoperative BSCVA during corneal refractive surgeries.

Adult↗
PubMed2003

Anatomical variations and clinical implications of the artery to the lingual nerve.

The pterygomandibular space is a critical anatomic area for the delivery of local anesthesia in the practice of dentistry. The neurovascular contents of this area are subject to trauma and its resultant local and systemic complications. This study of 202 cadaveric specimens reaffirms the literature as to the percent distributions of the superficial and deep routes of the maxillary artery and details for the first time the anatomic variations of the artery to the lingual nerve. This artery courses through the pterygomandibular space placing it at risk for injection trauma along with the other neurovascular contents. It has been uncommonly identified and referred to in the literature, yet it may be the first artery encountered when entering the space with a needle or during surgical intervention in the area.

Adult↗
PubMed2003

Anatomic variations of the frontal sinus.

INTRODUCTION: Minimally invasive approaches are increasing in popularity. We have undertaken an anatomic and radiological study of the frontal sinus that is frequently involved in the supercilliary minicraniotomy used to access the parasellar region. OBJECTIVE: We wanted to evaluate the prevalence and morphological characteristics of the frontal sinus in a certain population sample. METHODS: 98 randomly assigned individuals were subjected to CT examinations. The antero-posterior diameter, sagittal diameter, transverse diameter and total volume of the frontal sinus were calculated. RESULTS: The frontal sinus tended to be larger in males than in females with the exception of the transverse diameter (p < 0.10). CONCLUSION: Knowledge of the anatomic variations of the frontal sinus is important in surgical approaches through the superciliary arc in order to avoid complications such as infections and CSF fistula.

Adult↗
PubMed1985

High division of the median nerve: unusual anatomical variation.

An unusually high division of the median nerve in the forearm is reported. Recognition of this anatomical variation can help plastic surgeons make the proper diagnosis when encountering an incomprehensible clinical sign in the vicinity of the median nerve.

Child↗
PubMed1993

Anatomic variations of the pes anserinus: a cadaver study.

Both knees of 51 cadavers were dissected to identify anatomic variations of the pes anserinus. The tendons of the sartorius, gracilis, and semitendinosus were exposed through an inverted L subperiosteal incision beginning at the crest of the tibia. The upper border of the gracilis tendon was located an average of 5.5 cm from the anteromedial joint line. The tendons of the gracilis and semitendinosus fuse an average of 3.18 cm from their insertion and are firmly adherent to layer I (sartorius tendon). Forty-eight percent of the specimens demonstrated at least one of seven variations, ranging from fascial loops connecting the sartorius tendon with the medial collateral ligament to separate tendon slips from each of the three tendons inserting separately into the tibia or the crural fascia. This exposure is recommended to safely and efficiently dissect the tendons of the pes anserinus for use in reconstructive procedures of the knee.

Adult↗
PubMedDate not supplied

[Colonic interposition between kidney and psoas muscle: anatomical variation studied with CT].

Interposition of the colon between kidney and psoas muscle may represent a benign anatomical variant that can be recognized on Computed Tomography (CT) images. In our series including 428 abdominal CT examinations, the position of the bowel in the pararenal space was studied with respect to the kidney and the psoas muscle. To determine the colon position in the pararenal space, three CT scans, at the upper pole, midkidney and lower pole, for each side, were selected. The colonic interposition between the kidney and the psoas muscle was then correlated with patient's age, sex and amount of perinephric fat. The ascending colon was interposed between the kidney and the psoas muscle in 6/428 cases (1.4%), appearing more frequently in adult men. Of these 6 cases, CT showed decreased perinephric fat in three cases, normal in one and increased in two. No case of descending colonic interposition between the kidney and the psoas muscle was demonstrated. CT is a valuable tool to depict this anatomical variation, preventing misdiagnoses and complications arising from interventional procedures.

Adult↗
PubMed2004

Anatomical variation in origin and course of the thoracoacromial trunk and its branches.

The variations in origin and course of the thoracoacromial trunk (TAT) and its branches were studied in 178 cadavers during the routine dissection from the year 1982 to 2002. The TAT originated from the first part of the axillary artery (AA) in 13.4% cases of the right and 10.6% of the left axilla. The variations in origin of the branches of TAT were divided into three groups. First variation group showed deltoacromial (DA) and clavipectoral (CP) subtrunks of the TAT originating directly from the AA in majority of cases. Second group revealed clavicular branch of the TAT originating from the AA, whereas in the third group all classical branches originated directly from the AA and there was no existence of the TAT. The superior thoracic artery (STA) originated from the TAT in 16.8% (Confidence Interval, CI: 11.12-21.89) cases of the right and 6.1% (CI: 2.59-9.53) of the left axilla and the lateral thoracic artery in 39.8% (CI: 32.01-46.10) cases of the right and 29.3% (CI: 15.01-26.80) of the left axilla. The incidence of variations in origin of the TAT and its branches was found higher on right side. The knowledge of these variations is of anatomical and surgical interest. This information is useful for the surgeons dealing with the axillary region especially in case of reconstructive surgery.

Axilla↗
PubMed1991

Anatomical variations of the straight sinus on magnetic resonance imaging in the infratentorial supracerebellar approach to pineal region tumors.

Anatomical variations of the straight sinus (SS) were examined on magnetic resonance imaging (MRI) in 108 control cases and five cases with a pineal region tumor. The data of the latter were compared with the operative findings in the infratentorial supracerebellar approach. In the 108 control cases, the length of the SS was 51 +/- 5.2 mm. The angle of the SS to the nasion-tuberculum sellae line, the tuberculum sellae-inion line, and the nasion-inion line was 51 +/- 6.7 degrees, 44 +/- 5.0 degrees, and 47 +/- 5.0 degrees, respectively. The SS was inclined 1.4 +/- 4.5 degrees posteriorly to the bregma-inion line. The anatomical relationship between the SS and the corpus callosum was subgrouped into three types: in the common type (63%), the extended line of the slope of the SS is tangential to the upper aspect of the splenium of the corpus callosum; in the high-angle type (26%), the extended line is far above the tangent line; and in the low-angle type (11%), the extended line is far below the tangent line. The operative field was restricted by the steeply inclined tentorium in the case of the high-angle type, and the tumor was located much lower than the direction of the operative approach. In contrast, the tumor was easily exposed in the center of the wide operative field in the cases of low-angle type. The present study suggests that the preoperative MRI analysis of the angle of the SS is indispensable before taking the infratentorial supracerebellar approach to the pineal region tumors.

Adolescent↗
PubMed1993

Anatomical variation of pancreatobiliary ducts in biliary stone diseases.

Endoscopic retrograde cholangiopancreatography examinations were prospectively analyzed to determine whether anatomical variations of ductal systems have a role in the pathogenesis of cholecystolithiasis and choledocholithiasis. Included were 140 normal examinations (control group), 102 patients with cholecystolithiasis, and 68 patients with choledocholithiasis (primary stones in the common bile duct). Low entry of the cystic duct was observed frequently in patients with cholecystolithiasis (15.7% vs. 2.1% in control, p < 0.01). No preferential type of course of the cystic duct was observed in patients with cholecystolithiasis and choledocholithiasis. Separate openings of the bile and pancreatic ducts were significantly prevalent in patients with choledocholithiasis (53.5% vs. 30.6% in control, p < 0.01). Common channel was significantly short in patients with cholecystolithiasis. Incidence of juxtapapillary duodenal diverticula was significant in patients with choledocholithiasis. These observations suggest that some of the pancreatobiliary ductal anatomy may be closely implicated in the development of gallstone diseases.

Aged↗