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PubMed1975

Normal variations in tricuspid valve attachments to the membranous ventricular septum: a clue to the etiology of left ventricle-to-right atrial communication.

In 39 out of 95 normal specimens, there was either no commissure between the anterior and medial leaflets of the tricuspid valve, which resulted in an interrupted valve margin at the center of the membranous ventricular septum, or an incompletely formed commissure. It is suggested that one end of this spectrum of normal anatomic variations could have a direct relationship to VSD associated with left ventricle-to-right atrial communication.

Adolescent↗

PubMed2004

Unusual insertion of the coracobrachialis muscle to the brachial fascia associated with high division of brachial artery.

Anatomical variations of the coracobrachialis muscle (CBM) are common. We detected an abnormal form of the CBM of the left arm during human cadaver dissection. The CBM originated from the tip of the coracoid process of the scapula and divided into muscular and musculo-aponeurotic bellies. The muscular belly inserted into the middle of the anteromedial surface of the humerus, which is the normal anatomic insertion point of the CBM. The musculo-aponeurotic belly inserted into the medial intermuscular septum as well as the brachial fascia, creating a tunnel for the passage of the brachial artery. Inside the tunnel, the brachial artery bifurcated into the radial and ulnar arteries. No abnormality of the CBM, the brachial artery, or the median nerve was detected in the contralateral arm. The phylogenic, ontogenic, functional, and clinical importance of this variant muscle is described. Knowledge of such variations is of considerable importance during invasive and non-invasive investigative procedures or orthopedic, reconstructive, or surgical procedures.

Arm↗

PubMed2007

Incidence of cardiovascular disease in the dissecting room: a valuable teaching asset.

The purpose of this study was to determine the incidence of cardiovascular pathology in 50 cadavers in the dissecting room of the Department of Anatomy at Guy's Campus, King's College, London, and to demonstrate the importance of dissection in teaching the anatomy of normal and pathological hearts. After external evaluation of each heart the four chambers were dissected and studied. The features noted included evidence of coronary atherosclerosis, myocardial infarction, variations in coronary artery anatomy, valvular disease, variations in left ventricular wall thickness and atrial dimensions, and atrial anomalies. All the hearts studied had at least one pathology. The majority had severe coronary atherosclerosis (44) and aortic valve pathology (23). A large number had left ventricular hypertrophy (13) and left atrial enlargement (9). A small number showed evidence of myocardial infarction (4). Anatomical anomalies were also found, and included persistent foramen ovale (1), three coronary arterial ostia (3), and anatomical variations of the orientation of the main stem of the left coronary artery (2). This study demonstrates that dissection is not only an excellent way of studying normal cardiac anatomy, but also a valuable method for introducing common cardiac pathologies to the medical student.

Anatomy↗

PubMed1991

Patterns of initial tooth displacements associated with various root lengths and alveolar bone heights.

The present study was designed to investigate the nature of initial tooth displacements associated with varying root lengths and alveolar bone heights. A three-dimensional model of the upper central incisor was developed for the finite element analysis. Tooth displacements were determined at various levels of the tooth and the apicogingival levels of the center of resistance and centers of rotation were calculated. The results showed that moment-to-force values at the bracket level for translation of a tooth decreased with shorter root length and increased with lower alveolar bone height. In addition, apicogingival levels of the center of resistance shifted more gingivally to the cervix, or the alveolar crest with a shorter root. Alveolar bone loss also shifted the center of resistance toward the alveolar crest, whereas its position was more apical relative to the alveolar bone heights exhibited very slight changes in both cases. The centers of rotation from a single force varied substantially with a short root and alveolar bone loss. However, the relative distances of the centers of rotation from the alveolar crest in comparison with the alveolar bone heights were constant at 0.4 mm, with variations in the root length and alveolar bone height. Because this study showed that root length and alveolar bone height affect the patterns of initial tooth displacements both in the center of resistance and the centers of rotation and also in the amount of displacement, forces applied during orthodontic treatment should take into consideration the anatomic variations in the root length and alveolar bone height so as to produce optimal and desired tooth movement.

Alveolar Process↗

PubMed2006

Human bilateral doubled renal and testicular arteries with a left testicular arterial arch around the left renal vein.

During educational dissections at a human adult specimen, male, a complex picture of anatomical variants was encountered. Bilateral doubled renal arteries were found: on the right side superior hilar and inferior hilar renal arteries and on the left side superior hilar and inferior polar renal arteries. All these renal arteries emerged from the abdominal aorta. Also bilateral doubled testicular arteries were found. On the right side the medial testicular artery emerged from the abdominal aorta while the lateral testicular artery left the superior renal artery. On the left side the lateral and medial testicular arteries emerged as a common trunk from the abdominal aorta. This trunk originated from aorta behind the left renal vein and arched over that vein to descend and to divide in front of it. The two kidneys were keeping a fetal aspect, lobulated, more obvious on the left side. The right hepatic artery was found originating from the superior mesenteric artery; it coursed posterior to the portal vein and was sending the cystic artery. The right gastric artery emerged from the initial segment of the gastro-duodenal artery. Even though some morphological and topographical aspects regarding this complex anatomical variation have been described, it seems that the bilateral presence of doubled renal and testicular arteries has not been reported. The left testicular trunk arching over the left renal vein must be considered when discussing the nutcracker syndrome. During diagnostic and surgical approaches at the levels of the renal, gonadal and hepatic vessels, associations of anatomical variants and the bilateral presence of these must be suspected.

Adult↗

PubMed2005

Nerve supply of the brachioradialis muscle: surgically relevant variations of the extramuscular branches of the radial nerve.

The brachioradialis muscle is utilized in tendon-transfer operations, carried out for a variety of purposes. The extramuscular branches of the radial nerve to the brachioradialis were dissected and studied in 43 embalmed cadaveric specimens. The number of primary and secondary branches and the spatial locations of their origins and muscle-entry points was determined for each specimen. All distances were measured relative to the lateral epicondyle. A wide anatomic variation was observed in both the nerve branching pattern as well as the number and locations of muscle-entry points. A single primary nerve branch was found in 20 specimens, or 46.5% of the cases. On an average, single primary nerve branches arose from the radial nerve 30 mm proximal to the lateral epicondyle. In 16 of these cases, the primary branch splits into two to four secondary branches, and in four cases there was only one branch entering the muscle. Seventeen specimens had two primary branches whose origin points were separated by 5 to 40 mm with an average of 15 mm. In seven of these seventeen cases one or both of the primary branches split into secondary branches. Six specimens had three primary branches; the origin points of the most proximal and the most distal branch were separated by up to 30 mm with an average of 13 mm. Excluding the four cases with extensive fanning into multiple thin branches, the number of muscle-entry points ranged from 1 to 4 (mean 2.7). The locations of the muscle-entry points for all specimens were widespread ranging from 50 mm proximal and 40 mm distal to the lateral epicondyle with an average at 6 mm proximal to the lateral epicondyle. The greatest distance between muscle-entry points was 50 mm in a single specimen. In surgical procedures involving dissection of the brachioradialis muscle more proximal than 50 mm distal to the elbow, the extramuscular branch(es) of the radial nerve branches to the brachioradialis may be at risk.

Cadaver↗

PubMed1996

Anterior facial nerve rerouting in cranial base surgery: a comparison of three techniques.

Anterior rerouting of the facial nerve is a maneuver designed to enhance exposure of the jugular foramen and carotid canal during resection of cranial base tumors. Our clinical impression is that the degree of additional exposure afforded by moving the facial nerve varies considerably according to both anatomic variations and the technique used. Three possible techniques exist based on the extent of facial nerve mobilization and point of rotation: canal wall up-second genu pivot point (CWU-2G); canal wall down-second genu pivot point (CWD-2G); and canal wall down-first genu pivot point (CWD-IG). We anatomically studied 20 human cadaver heads to establish clinically relevant guidelines for the selective use of these techniques. At the level of the dome of the jugular bulb, the facial nerve mobilized anteriorly a mean of 4.2 mm for CWU-2G, 10 mm for CWD-2G, and 14 mm for CWD-1G. Detailed analysis of numerous measurements and rotation angles suggests that the typical exposure afforded by the various rerouting techniques is as follows: CWU-2G, complete exposure of the jugular bulb; CWD-2G, exposure of the jugular bulb and a mean of 6 mm of the posterior aspect of the carotid artery; and CWD-IG, exposure of the jugular bulb and entire carotid genu. Minimizing the amount of facial nerve manipulation needed to achieve sufficient surgical exposure helps optimize postoperative functional status.

Cadaver↗

PubMed1987

Paramedian thalamic and midbrain infarction: the 'mesencephalothalamic syndrome'.

Paramedian infarction in the region of the thalamus and upper midbrain may produce a wide range of neuro-ophthalmological, behavioural and motor abnormalities. The paramedian arteries arise from the first part of the posterior cerebral artery, also known as the basilar communicating artery. The particular arterial topography and its anatomical variation may result in unusual combinations of clinical signs, and infarction may be bilateral in some cases. Diagnosis is often aided by CT scanning and magnetic resonance imaging. Both atherosclerotic occlusion and embolism are thought to be responsible for these particular syndromes. We describe 3 cases that illustrate some of the various clinical features and underlying anatomical vascular arrangements which may be seen in this condition. Thalamic dementia was present in one case with evidence of bilateral thalamic infarction. A complex ophthalmoplegia and hemiparesis were seen in another case, and the third case had a combination of thalamic dementia and ophthalmoplegia.

Adult↗

PubMed2004

Differential diagnosis of asymmetrical renal cortex thickening and solid renal tumours.

Nowadays the number of asymptomatic, incidental tumors being detected increased as a result of the widespread use of noninvasive abdominal imaging modalities, including ultrasound and computed tomography (CT) and magnetic resonance imaging. The aim of the study is to analyze the atypical, complex morphologic changes and anatomical variants of renal structure, with tumor-like appearance. This is important especially in screening revealing tumors in asymptomatic patients or in patients with atypical symptoms. Material comprises a group of 186 patients in which the US examination was performed between 1996 and 2002, in 2nd Department of Radiology, Medical University of Lublin. In 20 patients the local thickening of renal cortex was found, protruding from the surface of the kidney, so-called "renal gibbus", constituting the anatomical variation. In eight cases the cortex thickening suggesting the presence of the renal gibbus, proved to be renal tumors. Diagnosing of small asymptomatic tumors, less than 3 cm in diameter, was difficult. They have appearance of protruding cortex thickening distorting the renal outlines. The assessment of renal outlines was an important morphologic factor. Small renal tumors showed anatomical anomalies. Regular tumor shape was rarely seen in larger tumors. The normal renal shape was more often seen in small tumors, while the large mass produces irregular distortion of renal outline. In four cases the oblique section of the renal pyramid has within the central part of kidney the appearance of oval pseudo-tumor. The differentiating of oval cortex thickenings protruding from the lateral renal margin--presenting "renal gibbuses"--and small renal tumors is difficult and requires supplementary helical CT examination with spatial reconstructions. Dynamic CT with early bolus of contrast agent and late sections is indicated. The lesion sizes, regularity of its margins, distortion of renal shape, echogenicity similar with the normal renal cortex were important in US examination. MR enhanced with DTPA and CT guided biopsy enables definite diagnosis.

Biopsy↗

PubMed1988

[Variations of the position of the stapes in the fossula of the round window and their surgical value].

The authors studied variations of the position of stapes in the fossula of ovale window on 300 preparations of temporal bones, under operating microscope. They noted three possible positions of the stapes: most commonly downwards to the promontorium (76%), much less frequently (15%) towards the bottom of the fossula, and rarely upwards to the facial canal (9%). Knowledge of these anatomic variations is of great importance in surgical procedures performed in this region.

Adult↗

PubMed2005

Sonographic imaging of the sciatic nerve division in the popliteal fossa.

BACKGROUND: We studied the anatomy of the sciatic nerve and its division into the tibial and peroneal part using handheld ultrasound in adults. We wanted to evaluate the feasibility of ultrasound-guided identification of the sciatic nerve in the popliteal fossa and the correlation of the findings by ultrasound with patients' characteristics. METHODS: 74 volunteers were randomly selected. Using a handheld ultrasound system with a 5-10 MHz linear array probe the popliteal fossa and the back of the thigh were examined and measured. Using a caliper the distance of the joint line to the nerve division was measured. The sciatic nerve and its division were depicted by ultrasound. RESULTS: We could depict the sciatic nerve in all volunteers and its division in 53 of 74 (72%) volunteers. The position of nerve division showed large anatomic variation. A significant correlation between the width of the knee-joint line and the depth of the nerve division could be demonstrated. We conclude that handheld ultrasound is able to depict the sciatic nerves division. To block the nerve by one injection a more proximal access or visualization by mobile ultrasound is recommended. In addition the surrounding anatomic structures can be depicted as well.

Adolescent↗

PubMed2001

[Bifid median nerve in the carpal tunnel: integrated imaging].

PURPOSE: Carpal Tunnel Syndrome (CTS) is a neuropathy caused by compression of the median nerve at the level of the wrist, which is caused by different pathologic conditions. In some cases it has been associated with anatomic variations of the median nerve, mainly with the early duplication of the nerve inside the carpal tunnel (III Group of Lanz). The treatment of CTS is mainly surgical consisting in decompression by transection of the transverse carpal ligament, which is better performed by endoscopic release. The aim of our study was to evaluate the possibility to detect this anatomic variant by integrated imaging and assess the value of this information for planning treatment. MATERIAL AND METHODS: We report 6 cases of bifid median nerve examined by Ultrasonography (US) using mechanic sectorial and linear array transducers operating at 10 to 13 MHz, and by MR imaging using 0.2 T equipment. RESULTS: In all cases US transverse scans showed two adjacent oval formations with a structure similar to that of the median nerve. CONCLUSIONS. MR imaging confirmed the sonographic findings in all cases. All patients underwent open surgical treatment by decompression of the median nerve; in all cases an early duplicated median nerve was confirmed.

Carpal Tunnel Syndrome↗

PubMed1998

First experience and technical aspects of isolated liver perfusion for extensive liver metastasis.

BACKGROUND: New drugs and modalities for locoregional tumor treatment in recent years may offer new potential for isolated liver perfusion in patients with nonresectable liver tumors. The purpose of this study was to prove the feasibility of arterial isolated liver perfusion and to assess the tolerance of perfusion with high-dose tumor necrosis factor (TNF). METHODS: Twelve patients with extensive liver metastases previously treated unsuccessfully with systemic chemotherapy underwent isolated hyperthermic liver perfusion using a heart-lung machine. High doses of mitomycin were administered in the first six and a combination of TNF and melphalan in the last six patients. RESULTS: No operative death occurred and no direct postoperative liver failure was observed in any patient. In cases of variations of the arterial hepatic blood supply, the perfusion was done through the splenic artery or an angiography catheter. Histologic analysis of tumor biopsy specimens obtained on the first postoperative day revealed major tumor necrosis in 8 of 12 patients. CONCLUSIONS: Isolated arterial perfusion of the liver is a complex surgical procedure that is feasible in patients with anatomic variations of the hepatic artery. The remarkable histologic response to perfusion in several pretreated patients, especially after application of high-dose TNF and melphalan, suggests that this modality is very effective in tumor killing.

Adult↗

PubMed2006

Endoscopic approach to colloid cysts.

OBJECTIVE: The aim of this study is to discuss the variations in the morbid anatomy of colloid cysts with its impact on the choice of endoscopic approach through a standard Kocher's burr hole. METHODS: This study was conducted on 18 patients between 1996 and 2006. All patients were operated through a single burr hole at Kocher's point using a rigid endoscope with a single working channel. The anatomical variations of the cyst and the foramen of Monro dictated the use of the transforaminal approach, the transseptal interforniceal approach or both. RESULTS: There were no mortalities or significant morbidities. The operative time ranged between 90 to 240 minutes (with a mean of 133 minutes). Five patients (27.7%) developed remediable postoperative chemical meningitis successfully controlled with steroids. Postoperative transient memory disturbance was observed in 3 patients (16.7%). One patient had a postoperative CSF leak that stopped spontaneously. Aspiration of the cyst's contents showed variable degrees of resistance to aspiration. The period of follow-up ranged between 5 months to 8 years and 3 months (mean: 4 years and 2 months). None of our patients showed radiological evidence of cyst recurrence during the follow-up period. CONCLUSION: Through a single right pre-coronal burr hole at Kocher's point, several endoscopic manoeuvres can be done. These include aspiration of the contents or its piecemeal removal, combined balloon squeeze and aspiration, foraminoplasty, pellucidotomy, coagulation of cyst capsule and ETV. The choice of the appropriate approach is largely dependent on the location of the cyst and the shape of the foramen of Monro. Coronal MRI may aid in preoperative evaluation of the tucked up retroforaminal growth of the cyst. We had no recurrence in our series with a follow-up reaching more than 8 years. This could be attributed to both the marsupialization and coagulation done for the remaining cyst capsule.

Adolescent↗

PubMed1993

Hepatic duct transection during laparoscopic cholecystectomy.

A rare anatomical variation was encountered during a laparoscopic cholecystectomy. The right hepatic duct emptied into the infundibulum of the gallbladder. This confluence then joined the left hepatic duct to form the common bile duct. The right hepatic duct was transected between the gallbladder and the common bile duct as a normal cystic duct would have been isolated and divided laparoscopicaly. This anatomic variant was recognized after further mobilization of the gallbladder from the liver bed. A laparotomy was performed to create a right hepatic duct enteric anastomosis. The case illustrates one possible pitfall that may be encountered during laparoscopic cholecystectomy.

Adult↗

PubMed1977

[Regularities and differences in the structure of the circulatory bed of the sternum].

The investigation has been carried out in 95 preparations of the anterior chest wall of corpses of humans of either sex aged from newborns to 90. It has been established that the blood supply of all the layers of sternum is brought about by the anterior and medial branches of the internal sternum artery forming subperiosteal plexuses on its anterior and posterior surfaces. The posterior plexus is better developed. Its loops are of less size and denser per a square surface unit. Three types of blood supply of the manubrium sterni posterior surface have been distinguished (right-side, balanced and left-side types) as well as two variations of blood supply of the sternum body (in the first variant two sternal branches approach the sternum at the level of every intercostal space, in the second variant--only one does). The outflow of the venous blood from the sternum is brought about into the anterior and posterior venous subperiosteal plexuses and then via one of the three anatomical variations into the internal thoracic veins. The subperiosteal network of the sternum in newborns and infants is of segmentary character and is formed in relation with developing ossification nuclei. With age, in the process of fusion of the ossification nuclei the subperiosteal network looses its segmentary character and acquires a common total character.

Adolescent↗

PubMed1983

[Sonography of the superior mesenteric artery. Normal anatomy variations and value for the analysis of retroperitoneal space occupying processes].

The superior mesenteric artery (SMA) can be demonstrated by ultrasonography under adequate conditions as a tubular liquid structure of 3 to 7 mms. in diameter, which parallels the abdominal aorta at a distance of 2 to 5 mms. The aortomesenteric distance is higher in patients with arteriosclerosis or aneurysm of the abdominal aorta, enlarged pre-aortic lymph nodes or other retroperitoneal masses. Its measurement can be recommended for quantitative assessment of retroperitoneal lymphadenopathy. Anatomic variations and postoperative changes may alter the course of the SMA. Measurement of the aortomesenteric angle is of no practical value.

Adult↗

PubMed1977

Irregular cervical dissemination of tumours of the maxillo-facial region.

In nearly 90% of lymphatic disseminations, metastasis of carcinomata of the oral cavity follows the normal regional anatomy of the efferent lymphatic system, and usually manifests itself in three homolateral filtering groups. More than 90% of lymphatic metastases occur in the first year following diagnosis of the primary tumour. Such a sequence may be regarded as "regular" metastasis. Anatomical variations and metastasis-induced or therapy-induced blockage of the efferent lymphatic system can change the pattern of metastasis to "irregular". The present studies are specially directed towards recurrence of metastasis, lymphangiosis blastomatosa, the so-called late metastasis as well as the problem of branchiogenic carcinoma. The explanation of clinical aspects has been substantiated with topographic-anatomical and histological findings as well as experience gained in lymphography and lymphoscintigraphy of the cervical lymphatic system.

Carcinoma↗