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PubMed1986

[The accessory deep peroneal nerve. Electrophysiologic study].

The extensor digitorum brevis muscle is innervated by the deep peroneal nerve. In some cases it has an additional innervation by the accessory deep peroneal nerve, a branch of the superficial deep peroneal nerve. The motor nerve conduction study with detection on the extensor digitorum brevis allows to detect such an anatomical variation. It has been found in twelve cases out of 67 subjects. In two cases it was bilateral and in two other cases the extensor digitorum brevis muscle was innervated by the accessory deep peroneal nerve alone. That anatomical variation has to be known in order to avoid errors in interpretating the peroneal motor nerve conduction velocity.

Adult↗

PubMed2002

Meningovenous structures of the petroclival region: clinical importance for surgery and intravascular surgery.

OBJECTIVE: The goals of this investigation were to perform a detailed analysis of petroclival microanatomic features, to investigate the course of the abducens nerve in the petroclival region, and to identify potential causes of injury to neurovascular structures when anterior transpetrosal or transvenous endovascular approaches are used to treat pathological lesions in the petroclival region. METHODS: Petroclival microanatomic features were studied bilaterally in seven cadaveric head specimens, which were injected with colored silicone before microdissection. Another cadaveric head was used for histological section analyses. RESULTS: A lateral or medial location of the abducens nerve dural entrance porus, relative to the midline, was correlated with the course and angulation of the abducens nerve in the petroclival region. The angulation of the abducens nerve was greater and the nerve was closer to the petrous ridge in the lateral type, compared with the medial type. The abducens nerve exhibited three changes in direction, which represented the angulations in the petroclival region, at the dural entrance porus, the petrous apex, and the lateral wall of the internal carotid artery. The abducens nerve was covered by the dural sleeve and the arachnoid membrane, which became attenuated between the second and third angulation points. The abducens nerve was anastomosed with the sympathetic plexus and fixed by connective tissue extensions to the lateral wall of the internal carotid artery and the medial wall of Meckel's cave at the third angulation point. There were two types of trabeculations inside the sinuses around the petroclival region (tough and delicate). CONCLUSION: The petroclival part of the abducens nerve was protected in a dural sleeve accompanied by the arachnoid membrane. Therefore, the risk of abducens nerve injury during petrous apex resection via the anterior transpetrosal approach, with the use of the transvenous route through the inferior petrosal sinus to the cavernous sinus, should be lower than expected. The presence of two anatomic variations in the course of the abducens nerve, in addition to findings regarding nerve angulation and tethering points, may explain the relationships between adjacent structures and the susceptibility to nerve injury with either surgical or endovascular approaches. Venous anatomic variations may account for previously reported cases of subarachnoid hemorrhage with the endovascular approach.

Abducens Nerve↗

PubMed1998

An anatomical study of the first extensor compartment of the wrist.

Anatomical variations of the first extensor compartment of the wrist are important during surgical operations of the wrist with de Quervain's disease. We studied 41 wrists from cadavers (16 whole cadavers and nine forearms) and the wrists of twenty-eight patients with de Quervain's disease to determine the variations of tendons and septa in the first extensor compartment. In 85.4 percent of the wrists from cadavers, the number of the tendons differed from the standard. There was septation in 9.75 percent of the dissected wrists. These anatomic variations are discussed for de Quervain's disease. In twenty-eight patients with de Quervain's disease, septation was found in thirteen patients (46.43%). In 82.14 percent of the wrists from the patients, the number of tendons in the first extensor compartment was more than two.

Adult↗

PubMed2006

[Cystic artery anatomy characteristics in minimally invasive surgical procedures].

UNLABELLED: Large patient series undergoing laparoscopic cholecystectomy fail to show anatomic variations which lead to intraoperative bleeding. METHOD: Cadaver material was used and corrosion casting and postmortem arteriography were employed. RESULTS: Three types of cystic artery were devised according to the results. Type 1 normal anatomy. Type 2 more than one artery in Calots triangle and Type 3 no artery in Calots triangle. DISCUSSION: only 40% of the second cystic artery is present in Calots triangle. The short second cystic artery is characteristic and its most often origin is from a segmental branch of the right hepatic artery. When there is no artery in Calots triangle its origin unusual, and the artery is either on the postero-lateral side of the cystic duct or it approaches the gallbladder through hepatic tissue. The specifics of MIS approach make changes in the way we understand the anatomic variations of the cystic artery. The classification is a result of practical experience and anatomical investigations.

Adult↗

PubMed1993

An anatomic and CT scan study of the lateral wall of the sphenoid sinus as related to the transnasal transethmoid endoscopic approach.

Interest in endoscopic sinus surgery has expanded to include the sphenoid sinus. While the transnasal transethmoid approach is an established route to the sphenoid sinus, instrumentation is brought close to the lateral wall. This study organizes the lateral wall of the sphenoid sinus into three distinct areas. Fifteen fixed cadaver specimens, 15 fresh specimens and 25 axial as well as coronal CT scans are used to examine each area of the lateral wall. The orbital apex, spongy vascular tissue of the cavernous sinus and the internal carotid artery are found in tandem sequence adjacent to the lateral wall of the sphenoid sinus. A highly pneumatized sphenoid sinus may attenuate the bone over the lateral wall placing the optic nerve and carotid artery at greater risk. Anatomic variations, as examined in this study, and limitations imposed by endoscopic vision via the transnasal transethmoid approach dictates a need to understand the anatomy as well as familiarity with endoscopic surgery. Axial CT scans of the sphenoid sinus can image anatomic variations which may compromise safety of the lateral sphenoid sinus wall.

Cadaver↗

PubMed2002

Overcoming vascular anatomic challenges to cardiac catheterization by the radial artery approach: specific techniques to improve success.

Anatomical variations in the peripheral vasculature can result in decreased procedural success rates for cardiac catheterization performed through the radial artery approach. We describe four categories of vascular challenges encountered in our catheterization laboratory: severe spasm, severe tortuosity, vascular stenosis, and congenital anatomical variations (e.g., accessory radial artery, radioulnar loop). For each situation, we provide a case report illustrating techniques that allowed for successful completion of the case.

Aged↗

PubMed2002

Applied anatomy of the genital branch of the genitofemoral nerve in open inguinal herniorrhaphy.

OBJECTIVE: To record the anatomical variations and clinical importance of the genital branch of the genitofemoral nerve in the inguinal canal. DESIGN: Neuropathology study. SETTING: General hospital, Taiwan. SUBJECTS: 58 cadavers. INTERVENTIONS: 116 dissections findings of the genitofemoral nerve in the inguinal canal. MAIN OUTCOME MEASURES: Anatomical variations. RESULTS: All the genital branches passed through the ventral aspect of the internal ring. Almost all these branches entered the ring and continued within the spermatic cord between the fibres of the cremaster and the internal spermatic fascia. In 59% the nerve was related to the inferior fibres and in 38% it was in relation to the lateral or medial fibres. In only 3% did the genital branch run outside the spermatic cord. CONCLUSION: To avoid damage to the genital branch of the genitofemoral nerve, suturing should be done over the dorsal aspect of the internal ring. The cremaster should be incised longitudinal rather than transversely and the genital branch of the genitofemoral nerve should be identified before repair of the posterior wall.

Cadaver↗

PubMed1997

Developmental variation in lumbosacropelvic anatomy of thoroughbred racehorses.

OBJECTIVE: To describe the incidence and types of gross osseous developmental variations and ages of physeal closure in the caudal portion of the thoracic and lumbosacral spine and the pelvis in a sample of Thoroughbred racehorses. ANIMALS: Thoroughbred racehorses (n = 36) that died or were euthanatized at California racetracks between October 1993 and July 1994. PROCEDURE: Lumbosacropelvic specimens were collected, and all soft tissues were removed. The osseous specimens were visually examined. RESULTS: Only 22 (61%) specimens had the expected number of 6 lumbar and 5 sacral vertebrae. Eight (22%) specimens had thoracolumbar transitional vertebrae, and 13 (36%) had sacrocaudal transitional vertebrae. Articular process asymmetries were present at 1 or more vertebral segments in 30 (83%) specimens. Intertransverse joints (2 to 4 pairs/specimen) were bilaterally distributed in the caudal portion of the lumbar spine and the lumbosacral joint in 31 (86%) specimens. Five (14%) specimens had asymmetric distribution of the intertransverse joints. Intertransverse joint ankylosis was found in 10 (28%) specimens. Lumbosacral vertebral body physeal closure occurred between 4.9 and 6.7 years of age; pelvic physeal closure occurred between 5.2 and 5.8 years of age. Iliac crest and ischial arch epiphyseal formation was evaluated, using a grading system, and fusion to the underlying bone occurred at 7.2 years and 5.4 years of age, respectively. CONCLUSIONS: Numerous vertebral anatomic variations were commonly found in a sample of Thoroughbred racehorses. CLINICAL RELEVANCE: Normal anatomic variations and ages of skeletal maturity need to be considered in clinical evaluation of the equine spine and pelvis for differentiation from pathologic findings.

Aging↗

PubMed2000

Musculo-tendinous junction of the flexor carpi ulnaris muscle. An anatomical study.

The aim of the study was to evaluate the occurrence of the anatomical variations of the musculotendinous junction of the flexor carpi ulnaris (FCU) muscle and the variations of its insertion onto the pisiform. One hundred cadaver specimens preserved according to Thiel's method were assessed. Following careful dissection, the distance between the musculotendinous junction and the pisiform and the width of the muscle belly were determined. Three typical anatomical variations were found: 1) a large muscle belly running distally almost to the insertion onto the pisiform; 2) the muscle belly ending more proximally, with some large fibres running parallel to the tendon and almost reaching the pisiform; 3) the musculotendinous junction ending more proximally, with only single fibres continuing distally. The length of the tendon was greater than 10 mm. A number of variations of the distal region of FCU were observed. The presence of muscle fibres almost reaching the insertion point onto the pisiform have to be considered when interpreting MRI or ultrasound findings of this region.

Aged↗

PubMed1989

Nasal endoscopy in chronic maxillary sinusitis.

The role of the anterior ethmoids in the pathogenesis of chronic maxillary sinusitis is still a subject of controversy. Although the symptoms of maxillary sinusitis may be clinically dominant, many previous studies have showed that the origin of this disease was, in most cases, located within the anterior ethmoid region. This study included 100 Egyptian patients, suffering from chronic maxillary sinusitis (confirmed by maxillary sinoscopy), who were subjected to 'systematic nasal endoscopy'. It was found that all cases of chronic maxillary sinusitis were associated with anatomical variations and/or pathological abnormalities of 'the ostiomeatal area'. It is recommended, therefore, that during the diagnosis and treatment of chronic maxillary sinusitis, attention should be given to the region of the middle meatus and anterior ethmoid complex (or 'ostiomeatal area') for any anatomical variations and/or pathological abnormalities in order to avoid recurrence of maxillary sinusitis. This is the basis of the procedure of functional endoscopic sinus surgery.

Adolescent↗

PubMed2006

Reliability of anatomical landmarks for skin perforators of the thoracodorsal artery perforator flap.

BACKGROUND: The thoracodorsal artery perforator flap was first introduced in 1995. Many authors focused on using anatomical landmarks to identify skin perforators and on thinning procedures for a skin paddle. In this study, we used the superthin free thoracodorsal artery perforator flap for resurfacing shallow defects of the extremities in 10 patients. METHODS: Two anatomical landmarks previously presented by other authors were used for the guidance of flap elevation. The first landmark represented the site of the proximal skin perforator originating from the descending branch of the thoracodorsal artery, and the second landmark marked the site of the thoracodorsal neurovascular hilum. Ten flaps were performed, and all skin perforators originated from the descending branch of the thoracodorsal artery. The skin paddle carried only skin and the superficial adipose layer, and the largest skin paddle was 23 x 9 cm. RESULTS: All defects were resurfaced with smooth contour, except for one flap in which the authors encountered flap tip superficial necrosis. The operative findings did not coincide with the first anatomical landmark in five patients. Likewise, these findings were not consistent with the second landmark in eight patients. In four patients, the thoracodorsal neurovascular hilum was located at the same level of the scapular tip or even above it. These unwanted anatomical variations increased the difficulty of exploration for skin perforators. CONCLUSIONS: The thoracodorsal artery perforator flap is a feasible choice for shallow defects in superthin form. Using a color Doppler device to identify the skin perforators preoperatively is highly suggested to prevent unexpected anatomical variations.

Adult↗

PubMed2005

[Stenosed spaces of ostiomeatal complex and chronic sinusitis (an analysis of 94 cases)].

OBJECTIVE: To discuss the relationship between the stenosed spaces of ostiomeatal complex (OMC) and chronic sinusitis, and the relative factors causing the stenosed spaces. METHOD: Having nasal obstructing, discharging, headache and other clinical symptoms, 94 patients (179 sides of nasal cavity and sinus) were examined with coronal and high resolution CT scanning. The CT manifestations of the stenosed spaces and the anatomic variations of OMC were comparatively analyzed between the inflammatory sinuses and the normal ones. RESULT: The incidence of the stenosed spaces was difference between the inflammatory sinuses and the normal ones and there was significant statistically (P < 0.01). But, the incidence of the anatomic variations was not (P > 0.05). CONCLUSION: A significant correlation exists between the stenosed spaces of OMC and chronic sinusitis. It is helpful to the functional endoscopic sinus surgery (FESS) to understand various kinds of the stenosed space of OMC with sinusitis.

Adolescent↗

PubMed2005

Assessment of the radial artery and hand circulation by computed tomography angiography: a pilot study.

OBJECTIVES: The radial artery (RA) is increasingly being used as a coronary bypass graft. Results of a previous study using Doppler ultrasound and histopathologic examinations indicated that the RA has a higher incidence of preexisting intimal hyperplasia, medial calcification, and atherosclerosis than the internal thoracic artery. The aims of this study were to evaluate the use of computed tomographic angiography (CTA) to display hand collateral circulation, to define the criteria for an abnormal CTA test result, and to demonstrate usefulness of CTA as an alternative to conventional angiography for evaluation of the radial artery. MATERIALS AND METHODS: Sixteen patients scheduled for coronary artery bypass grafting entered this study. We performed 32 examinations of forearm and hand arterial anatomy in these patients. CTA was performed in patients with a normal Allen test result, except 1 patient who had a persistent median artery. Soft tissue density forehand roentgenography was performed in all patients before the CTA evaluation. There was no selection of patients in relation to patient characteristics. As a risk factor for radial artery calcification, 6 of the patients had diabetes mellitus, 6 had aortofemoral occlusive disease, and 4 had a history of smoking. RESULTS: Bilateral forearm arteries were visualized in all patients. Severe RA calcification was found in 1 patient, and distal occlusion was found in another patient. Focal RA calcification was noted in 2 patients. In the remaining patients no radial artery calcification or occlusion was noted. Anatomic variation of the upper limb arteries was shown in 2 patients; these variations were persistent median artery with absence of the radial and ulnar arteries and high bifurcation of the radial artery from the brachial artery. CONCLUSION: CTA is useful and safe for detection of radial artery calcific disease and assessment of the forehand circulation and its anatomic variations. Preoperative imaging of the RA is a means to avoid unnecessary forearm exploration or inadvertent use of a diseased conduit in coronary artery bypass candidates with multiple risk factors such as diabetes mellitus.

Age Factors↗

PubMed2001

Anatomy of the knee extensor mechanism: correlation with patellofemoral arthrosis.

The patellofemoral articulation is a common and significant source of disability and discomfort in the aging population. This study examined the anatomy of the knee extensor mechanism in patients having primary total knee arthroplasties, characterized the anatomic variations of the extensor mechanism, and correlated these findings with the location and extent of osteoarthritic change of the patellar undersurface. Sixty-two knees (57 patients) were evaluated prospectively. Specific characteristics that were analyzed included the mean Outerbridge grade for rating patellar cartilage degeneration and anatomic patterns of the extensor mechanism. Knees with a quadriceps tendon width at 2 and 5 cm above the patella that differed by less than 1 cm had more statistically significant patellar degeneration in all patellar locations than knees with tendon width differences greater than 1 cm. Anatomic variations, such as tendons with minimal increments in width in the proximal-distal direction, may be associated with an increasing amount of patellar arthrosis at the lateral facet, central ridge, and, most significantly, medial facet.

Aged↗

PubMed2006

Clinical interest of digestive arterial trunk anastomoses.

Arterial vascularization of the gastrointestinal tract is a three-level system composed of the coeliac trunk, and both superior and inferior mesenteric arteries. The three levels are joined together via arterial trunk anastomoses such as the so-called and well-known Riolan arcade or supramarginal arcade. The aim of this study was to review the embryology of the digestive arteries in order to understand the anatomic variations, the development of the arterial trunk anastomoses and the potential collateral circulation in the case of obstruction of one or several arterial trunks. The arch theory by Mac Kay and Tandler longitudinal arterial anastomosis account for the genesis of the arterial trunk anastomoses and the main anatomic variations. The coeliac trunk and the superior mesenteric artery are joined together via the pancreaticoduodenal arcades and the Bühler arcade. These anastomoses are divided during pancreatic resections but developed in the case of coeliac trunk stenosis. The mesenteric arteries are joined together by the Riolan, Villemin arcades and by the marginal artery of Drummond. This collateral circulation and the Riolan arcade in particular, is utilized during left colonic resection. In the case of this collateral circulation insufficiency, inferior mesenteric artery reimplantation is necessary during abdominal aortic aneurysmectomy. Arteriopathy, more and more frequent due to population ageing is responsible for frequent obliteration of one or several digestive arterial trunks with subsequent development of collateral circulation. For such reasons, a sound knowledge of digestive arterial anatomy is an absolute prerequisite for surgical practice.

Arteriovenous Anastomosis↗

PubMed2005

Preoperative assessment of the aberrant bile duct using multislice computed tomography cholangiography.

BACKGROUND: This study aimed to determine the frequency of anatomic variations of bile ducts (aberrant bile ducts) using multislice helical computed tomography (MCT) cholangiography. METHODS: MCT scanning was performed after slow infusion of 100 mL meglumine iotroxate. Overlapping axial images, taken at 0.5-mm intervals, were reconstructed to create a multiplanar reconstruction with volume rendering. We analyzed anatomical variations of the biliary tree by MCT cholangiography. RESULTS: In a total of 113 patients, MCT cholangiography provided clear images of aberrant bile ducts in 18 patients. Major type (draining a particular segment of the liver) was found in 9 cases (8%) and minor type (draining a particular subsegment of the liver) in 9 cases (8%). CONCLUSIONS: Preoperative MCT cholangiography provides important information about the precise biliary anatomy and can reveal unexpected aberrant bile ducts prior to biliary surgery, especially laparoscopic cholecystectomy.

Bile Ducts, Extrahepatic↗

PubMed1995

[The use of contrast media for quality assurance in radiotherapy planning].

PURPOSE: The target volume definition in radiation therapy was evidently improved by CT and MRI. Basis of treatment planning, however, remains the therapy simulator. Important instruments for adequate fluoroscopic treatment planning are contrast media that recently have been applied less out of legal and professional reasons. Aim of this work is to evaluate the possible benefit of contrast media applications. PATIENTS AND METHODS: In 1303 simulations between 1.1.1993 and 30.9.1993 105 times intravenous contrast media were applied, supplied by oral or endolymphatic contrast agents. It was studied if the previously intended plan had to be altered due to contrast media application. RESULTS: In 17 out of 105 cases (16.2%) the target volume or the preplanned technique had to be altered after contrast media application. Main reason was the existence of anatomical variations especially in kidney and small bowel detected by use of contrast agents. So standard indications for contrast media applications were defined. CONCLUSIONS: Contrast media are an important tool in treatment planning that should be orientated on diagnostical standards. Applications of contrast agents facilitate the detection of anatomical variations and the selection of the appropriate technique in order to shield sensitive tissues. The therapeutical and legal benefit outweigh potential hazards due to intolerances or professional obstacles.

Contrast Media↗

PubMedDate not supplied

[The internal thoracic blood vessels (internal thoracic arteries and veins) and their practical significance].

Internal thoracic blood vessels (A. et Vv. thoracicae internae) are parietal vessels of the thoracic anterior wall. Because of their position, they are often exposed to injuries during the fracture of the ribs and the sternal bone. These facts require a general knowledge about the anatomical variations of these vessels, specifically the knowledge concerning their mutual relationship, their anastomoses and their distance from the lateral margins of the sternal bone. Due to the poor and different data in the available literature, we directed our investigations towards the study and confirmation of the described anatomical variations of the internal thoracic blood vessels. In this study we investigated the distance between the internal thoracic artery and the lateral margins of the sternal bone, the level of its bifurcation, the number of the internal thoracic veins and anastomoses between them. The investigation was carried out on 300 formalin specimens consisting of the anterior wall of the thorax (persons of different ages and sexes) by using the method of dissection and the method of contrast injection. In adults (200 specimens), the distance between the arterial trunk and the lateral margin of the sternal bone was not equal in the first fifth or sixth intercostal spaces, but in children up to five years of age (100 specimens), the distance was almost the same. In adults, the internal thoracic artery was nearest to the sternal bone in the first intercostal space, but going downward the artery was gradually more and more distant from the sternum and in the sixth intercostal space the distance measured approximately from 11 mm to 13 mm. In children, the distance of the artery from the lateral margin of the sternal bone, just in the above mentioned intercostal spaces, was from 5 mm to 10 mm. There was no difference according to sex in any of the two groups. Most frequently, the internal thoracic artery gave off its terminal branches at the level of the sixth costal cartilage (adults--35% and children--45%), and most rarely, the bifurcation of the artery was at the level of the seventh costal cartilage (adults--10% and children--8%). The internal thoracic vein that accompanies the same named artery, could be either single or double, on one or both sides. In cases of double veins-the artery was situated between the two of them, but in cases of single vein-the vein was located medially to the artery. In 82% of cases in the adult group, and in 69% of cases in the children-group, there were two veins accompanying the artery. The right and the left internal thoracic veins were connected in the region of the sternal bone by the retrosternal venous net (specifically in the region of the manubrium) and by one venous vessel lying in front of the xiphoid process. According to the position and the course of that venous vessel it could be called "arcus venosus prexiphoideus". The internal thoracic blood vessels were enclosed by the unique fascial sheath. They were superiorly separated from the costal pleura by the endothoracic fascia and inferiorly by the transversal thoracic muscle (m. transversus thoracis). The safest approach to the internal thoracic artery was at the level of the second and the third intercostal space. During the approach through some of the lower intercostal spaces it was necessary to be very careful because they could be narrowed at their anterior ends.

Adult↗