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At least 235 records · Page 13Linked to original sources
PubMed1998

Activation mapping from the coronary sinus may be limited by anatomic variations.

The purpose of this study was to examine the anatomic relationship between the mitral annulus (MA) and the coronary sinus (CS). Fifty consecutive hearts of 31 men and 19 women, 63.5 +/- 13.7 years of age, were examined at autopsy. MA was divided perpendicularly to the annular plane into an anteromedial block and a posterolateral block by sectioning from the CS ostium through the center of MA. The posterolateral block was subdivided radially into five equal sections at 36 degrees, 72 degrees, 108 degrees, 144 degrees, and 180 degrees. The distance from the ventricular endocardium under MA to the nearest wall of CS (D) was measured in each cross-section. D measured 9.7 +/- 2.3, 10.9 +/- 3.3, 10.2 +/- 3.6, 9.2 +/- 3.4, and 8.2 +/- 2.9 mm at 36 degrees, 72 degrees, 108 degrees, 144 degrees, and 180 degrees, respectively. D at 72 was significantly longer than at 144 degrees and 180 degrees (P < 0.01). Likewise, D at 108 degrees was significantly longer than at 144 degrees and 180 degrees (P < 0.05). The population was divided according to the morphology into five patterns. "Type C," the pattern that separated in the middle section and then reapproximated, was more common (66%) than any other pattern. D was confirmed to be longest at the level of the 72 degrees section, corresponding to a left posterolateral free-wall location. The potential mapping in CS would be easily modified by this anatomic feature. When mapping activation from the CS, the electrophysiological data should be interpreted in light of these anatomic findings.

Cadaver↗
PubMed2006

A secondary middle turbinate co-existing with an accessory middle turbinate: an unusual combination of two anatomic variations.

The anatomy of the nasal cavity lateral wall is quite complex; this is where most anatomical anomalies occur. The secondary middle turbinate, a bony projection that arises from the lateral nasal wall, is a rare variation, differing from the accessory middle turbinate by its distinct developmental origin. We report on an unusual case involving a combination of these two turbinate variations. We believe that detailed knowledge of anatomical anomalies in the sinonasal tract is critical for successful clinical management and important in allowing the surgeon to perform safe functional endoscopic sinus surgery.

Humans↗
PubMed2000

Vascular anatomic variations in second toe transfers.

To devise a new classification of vascular variations in second toe transfer we analyzed the anatomic details of the first dorsal metatarsal artery in 304 cases of second toe transplantation and the venous structure in 200 cases. According to location, the arterial vascularity was classified as superficial (18% of cases), intramuscular (54%), inframuscular (23%), and absent (5%). According to diameter, it was classified into large (16%), medium (64%), and small (20%). Based on branching pattern, the artery was classified into ramifying type (88%), main trunk (4%), and fine branch type (8%). The venous drainage of the second toe was categorized as greater saphenous vein main trunk type, greater saphenous vein fine branch type, dorsal digital vein main trunk type, and dorsal digital vein fine branch type. Variations of the first dorsal metatarsal artery are common. Classification should be done according to its location, diameter, and branching pattern at the toe web. Regardless of location, big vessels entering the second toe are the most important attribute for successful outcome.

Adolescent↗
PubMed2006

Anatomical variations of the hepatic artery: study of 932 cases in liver transplantation.

The aim of this study was to identify and to classify anatomical hepatic artery (HA) variations concerning 932 HA dissections in liver transplantation (LT). Normal HA distribution was found in 68.1%. Variations of HA were detected in 31.9% and were divided into three groups describing 48 common hepatic artery (CHA) anomalies, 236 left or right hepatic artery (RHA) anomalies and 13 rare variations including one case of RHA stemmed from the inferior mesenteric artery and one case of normal CHA passed behind the portal vein. The authors propose a modified classification for HA anomalies which are based on the origin of the hepatic arterial supply (either by the CHA as the only source of the arterial vascularization or by additional or replaced right and left arteries) in order to improve management of liver disease thus as in LT.

Hepatic Artery↗
PubMed1994

Endodontic implications of anatomical variations and developmental anomalies in maxillary and mandibular anterior teeth.

Endodontic treatment of maxillary and mandibular anteriors does not generally offer strenuous challenges to the skilled practitioner. Most cases are relatively straightforward and can be treated without complication. Anatomical and developmental variations do exist in these teeth, however, which can add an enormous degree of technical complexity, and even doom endodontic treatment to failure. The prudent clinician must be aware of these variations, modify treatment procedures accordingly, and inform the patient of these possible causes of treatment failure.

Cuspid↗
PubMed1991

Anatomic variation of the corpus callosum in persons with gender dysphoria.

Previous postmortem anatomical studies have demonstrated differences between male and female in the size and shape of the splenium of the corpus callosum. The current study using the magnetic resonance imager compares the corpus callosum in 20 transsexuals and 40 controls to determine if the anatomic variance is related to anatomic sex or gender identity. No statistical differences were found in the cross-sectional areas of the entire corpus callosum, regardless of genetic sex or gender. However, the genetic males did have a larger whole-brain cross-sectional area. Also, even though there was a wide range of differences in shape and size in the splenium, the study found no significant differences between the sexes or between transsexual patients of either sex and the controls.

Adult↗
PubMed1997

Anatomic variations of the musculocutaneous nerve in the arm.

To determine the course and anatomic relationships of the musculocutaneous nerve in the arm, we dissected 54 cadaver arms and measured the length of any interconnection between the musculocutaneous nerve and the median nerve (36% of dissections; mean, 1.77 cm) and the distance from the coracoid process to (1) the musculocutaneous nerve (mean, 0.46 cm distal); (2) the median nerve (mean, 1.91 cm distal); (3) the musculocutaneous nerve's entrance to and exit from the coracobrachialis muscle (mean, 4.99 cm and 7.55 cm, respectively); and (4) the musculocutaneous nerve's entrance into the biceps muscle (mean, 11.66 cm). The high percentage of anomalies found emphasizes the complexities and irregularities of this anatomic region with regard to surgical approaches.

Arm↗
PubMedDate not supplied

Anatomical variations of the sensory nerves to the fibular osteocutaneous flap.

OBJECTIVE: To describe the anatomical relationship of the sural sensory nerve complex to the posterior crural intermuscular septum (PS), the key anatomical structure for the osteoseptocutaneous fibula skin paddle. DESIGN: Anatomical study. SUBJECTS: Twenty-two legs from 11 cadavers (7 females and 4 males). RESULTS: The lateral sural cutaneous (LSC) nerve, present in 20 of 22 legs, divides into lateral and medial branches near the head of the fibula. The LSC nerve and its medial branch course away from the PS, whereas the lateral branch tends to course toward the PS. The lateral branch courses nearest to the PS at a median distance of between 4 cm proximally and 3 cm distally. The medial branch of the LSC nerve terminates approximately in the middle of the leg, and the lateral branch of the LSC nerve terminates within 7 cm below the head of the fibula. The peroneal communicating branch is thicker than the LSC nerves; however, it is further from the PS in the upper leg. CONCLUSIONS: The LSC nerve is the most consistent and accessible donor sensory nerve in the posterior leg for harvest with the osteoseptocutaneous fibula free flap. Results of this study will assist the surgeon in harvesting a sensory nerve with the osteoseptocutaneous fibula free flap, bringing this potentially sensate flap into more common use. Arch Facial Plast Surg. 2000;2:252-255

Anthropometry↗
PubMed1986

[Hereditary factors and their causative role in anatomic variation].

As demonstrate the literature data and the authors' observations on the composition of the anatomical structures of the extremities at the popliteal pterigyum syndrome of Smith-Lemley-Optis, as well as at some other monogenic syndromes, the manifestation of the anatomical changeability in humans is defined, to an essential degree, by hereditary factors. A suggestion is made that investigation of the anatomical changeability in connection with genetic peculiarities of the organism makes it possible to approach the causal interpretation of the variants and the developmental anomalies and comprehend the sources of multiplicity of forms and structure of the human organs and systems.

Chromosome Aberrations↗
PubMed2005

Anatomical variations of the second thoracic ganglion.

In recent years the second thoracic ganglion has gained anatomical significance as an important conduit for sympathetic innervation of the upper extremity. Thoracoscopic excision of the second thoracic ganglion is now widely recognized as affording the most effective treatment option for palmar hyperhidrosis. This study recorded the incidence, location and associated additional neural connections of the second thoracic ganglion. Bilateral dissection of 20 adult cadavers was undertaken, and all neural connections of the second thoracic ganglion were recorded. Nineteen cadavers (95%) demonstrated additional neural connections between the first thoracic ventral ramus and second intercostal nerve. These were classified as either type A (47.5%) or type B (45%) using the intrathoracic ramus (nerve of Kuntz) between the second intercostal nerve and the ventral ramus of the first thoracic nerve as a basis on both right and left sides. The second thoracic ganglion was commonly located (92.5%) in the second intercostal space at the level of the intervertebral disc between the second and third thoracic vertebrae. Fused ganglia between the second thoracic and first thoracic (5%) and stellate (5%) ganglia were noted. These findings should assist the operating surgeon with a clear knowledge of the anatomy of the second thoracic ganglion during thoracoscopic sympathectomy with a view to improving the success rate for upper limb sympathectomy.

Adult↗
PubMed1993

Wrist anatomy: incidence, distribution, and correlation of anatomic variations, tears, and arthrosis.

We dissected 393 wrists to evaluate the incidence and distribution of anatomic features, arthrosis, chondromalacia, and soft tissue lesions. The data were then analyzed for any statistically significant associations among the different variables. The most common (73%) lunate morphology had a separate medial facet on its distal surface for the hamate. The capitate had a separate facet for the fourth metacarpal in 86% of the wrists. Fourth metacarpals with a dorsal radial facet, either separate from or connected to the rest of the fourth metacarpal base, were the most common types of fourth metacarpal. Cartilage erosion with exposed subchondral bone was identified in 58% of the wrists. It was most commonly at the proximal pole of the hamate (28%). Tears of the ligaments and/or the triangular fibrocartilage complex were identified in 56% of the wrists. The triangular fibrocartilage complex was found torn in 36% of the wrists. The lunotriquetral interosseous ligament was torn in 36% of the wrists, and the scapholunate interosseous ligament was torn in 28% of the wrists. There was a communication between the proximal wrist joint and the pisotriquetral joint in 88% of the 76 wrists, which were further dissected to assess this issue. Statistical analysis of the data found a significant correlation between the presence of cartilage erosion at the proximal pole of the hamate and the presence of a lunate facet. There was also a significant correlation between the presence of a tear in the scapholunate interosseous ligament and the presence of cartilage erosion in the scaphoid-trapezium-trapezoid joint. Analysis of the paired wrists from 169 cadavers revealed that the same soft tissue tear or combination of tears was present bilaterally in 39% of the pairs. Cartilage erosion was present bilaterally in the same location or locations in 27% of the pairs.

Adolescent↗
PubMed1992

Lumen diameter of normal human coronary arteries. Influence of age, sex, anatomic variation, and left ventricular hypertrophy or dilation.

BACKGROUND: Precise knowledge of the expected "normal" lumen diameter at a given coronary anatomic location is a first step toward developing a quantitative estimate of coronary disease severity that could be more useful than the traditional "percent stenosis." METHODS AND RESULTS: Eighty-three arteriograms were carefully selected from among 9,160 consecutive studies for their smooth lumen borders indicating freedom from atherosclerotic disease. Of these, 60 men and 10 women had no abnormalities of cardiac function, seven men had idiopathic dilated cardiomyopathy, and six men had left ventricular hypertrophy associated with significant aortic stenosis. Lumen diameter was measured at 96 points in 32 defined coronary segments or major branches. Measurements were scaled to the catheter, corrected for imaging distortion, and had a mean repeat measurement error of 0.12 mm. When sex, anatomic dominance, and branch length were accounted for, normal lumen diameter at each of the standard anatomic points could usually be specified with a population variance of +/- 0.6 mm or less (SD) and coefficient of variation of less than 0.25 (SD/mean). For example, the left main artery measured 4.5 +/- 0.5 mm, the proximal left anterior descending coronary artery (LAD) 3.7 +/- 0.4 mm, and the distal LAD 1.9 +/- 0.4 mm. For the LAD, lumen diameter was not affected by anatomic dominance (right versus left), but for the right coronary artery, proximal diameter varied between 3.9 +/- 0.6 and 2.8 +/- 0.5 mm (p less than 0.01) and for the left circumflex, between 3.4 +/- 0.5 and 4.2 +/- 0.6 mm (p less than 0.01). Women had smaller epicardial arterial diameter than men (-9%; p less than 0.001), even after normalization for body surface area (p less than 0.01). Branch artery caliber was unaffected by the anatomic dominance but increased with branch length, expressed as a fraction of the origin-to-apex distance (p less than 0.001). Lumen diameter was not affected by age or by vessel tortuosity but was significantly increased among men with left ventricular hypertrophy (+ 17%; p less than 0.001) or dilated cardiomyopathy (+ 12%; p less than 0.001). CONCLUSIONS: This is a reference normal data set against which to compare lumen dimensions in various pathological states. It should be of particular value in the investigation of diffuse atherosclerotic disease.

Adult↗
PubMed2001

Important anatomic variations of the sinonasal anatomy in light of endoscopic surgery: a pictorial review.

Advances in surgical techniques and instrumentations, utilization of the imaging tools, and understanding the regional anatomy have served to make functional operations with less complications in the paranasal sinus area. In the context of this article, some of these anatomical structures and their variations were reviewed through images. These structures were as follows: course of the anterior ethmoidal artery; roof of the ethmoid; lamina papyracea; uncinate process; optic nerve; and internal carotid artery.

Arteries↗
PubMed2004

Preserving and sharing examples of anatomical variation and developmental anomalies via photorealistic virtual reality.

Computer graphics technology has made it possible to create photographic-quality virtual specimens from real anatomical material. One technique for doing this, QuickTime Virtual Reality (QTVR), results in virtual specimens that are easily shared on the Internet and displayed as standalone entities or incorporated into complex programs or Web sites. A compelling use of this technology is the sharing of rare specimens such as unusual variations, developmental anomalies or gross pathology. These types of specimens have traditionally been confined to anatomical museums, but could serve a much more useful existence as freely shared virtual specimens. An example presented here is a relatively rare developmental defect in the embryonic aortic arches that results in a right-sided aortic arch coursing posterior to the trachea and esophagus. In a time of ever increasing restraints on the practical side of anatomy education, an Internet-based library of human variation and other rare specimens would be a useful supplement to students' limited exposure to the human body. Since the discovery and preparation of specimens would be the rate-limiting step in producing such a collection, we propose the establishment of a center for virtual specimen creation and preservation through a cooperative effort by gross anatomists and pathologists in contributing the source material. This collection, a work in progress, is available at www.anatomy.wright.edu/qtvr.

Anatomy↗
PubMed1989

The bile duct system and its anatomical variations.

The embryology and anatomy as well as the variations and abnormalities of the biliary system are briefly reviewed. Emphasis is placed upon the intimate anatomical relationship between extrahepatic bile duct, gallbladder, head of the pancreas and its vascular supply. The variations and abnormalities of the biliary system relevant to the endoscopist and surgeon are stressed.

Bile Ducts↗