Anatomically related variations in trace-metal concentrations in hair: a comment.
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Hair↗
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Anatomically-related variations in trace-metal concentrations in hair.
Scalp-hair analysis is used as an indicator of trace-metal concentrations in the human body. The major shortcoming of this approach is the inability to differentiate between endogenous and exogenous trace metals. Our analyses show no correlation between the concentrations of calcium, magnesium, copper, iron, or zinc in scalp hair and pubic hair in 67 donor-matched hair samples. We interpret this as a strong indication that exogenous trace metals make a significant contribution to the results for trace metals in human hair.
Body Burden↗
Musculotendinous variations about the medial humeral epicondyle.
Anatomical variations in the musculofascial structures about the region of the medial humeral epicondyle were evaluated in 104 extremities in sixty-four cadavers. This study demonstrated presence of an Osborne's band in 77%, of some degree of ulnar subluxation in 25%, of an epitrochlearis anconeus muscle in 11%, the ulnar nerve beneath the medial head of the triceps in 24%, the medial head of the triceps within the floor of the cubital tunnel in 28%, the presence of a rudimentary supracondylar process in 1.5%, and a high origin of the pronator teres in 17% of the cadavers. There was a significant association between the presence of an epitrochlearis anconeus muscle and the ulnar nerve being completely covered by the medial head of the triceps muscle (p less than .001). There was a significant relationship between the presence of the medial head of the triceps in the cubital tunnel and ulnar nerve subluxation (p.001). The high origin of the pronator teres may provide a proximal site for "double crush" syndromes of the median nerve.
Arm↗
An examination of the spectrum of anatomic defects and variations found in eight cases of trisomy 13.
We report the anatomic variations found in four additional cases of trisomy 13. Data from these and four previous cases [Colacino and Pettersen, 1978] are utilized to define a muscle phenotype. Previously unreported defects include the bilateral presence of cervical ribs and the bilateral absence of 12th thoracic ribs in five of the eight cases. One unusual developmental defect of the great vessels is also described. The findings suggest that a definitive diagnosis of trisomy 13 can be made on the basis of six muscle variations.
Abnormalities, Multiple↗
Rare variation in course and affluence of internal iliac vein due to its anatomical and surgical significance.
During regular dissection of the retroperitoneal region, three uncommon anatomical variations of the internal iliac veins were found on dissected specimens: in the first case, the internal iliac veins converge forming a common trunk draining into the left external iliac vein. In the other two cases, the internal iliac vein crosses the median plane and flows into the contralateral common iliac vein. These anomalies result from a persistence of the embryonic inferior branch of the cardinal vein and are important to be known for they may be undetected or may not appear in imaging. These data have implications for both pelvic surgeons and anatomists who manipulated this anatomical area.
Dissection↗
Variations in percutaneous absorption of testosterone in the rhesus monkey due to anatomic site of application and frequency of application.
This study determines if the anatomic region affected percutaneous absorption in the rhesus monkey, an animal model with some relevance to man. Percutaneous absorption of testosterone (13.3 microgram/cm2) from the ventral forearm was 8.8 +/- 2.5%. Absorption from the chest was slightly less (5.3 +/- 0.6%) while that from the cheek was about the same (9.6 +/- 0.2%). Absorption from the scalp was greatly increased (20.4 +/- 2.7%), that from the vagina was the greatest (63.1 +/- 2.6%). As previously noted in man, anatomic variation in skin absorption exists in the rhesus. The ratio of scalp absorption to ventral forearm absorption in the rhesus was similar to that in man. The next objective was to determine the percutaneous absorption of testosterone when applied as a single dose or on a repetitive basis. There was no substantial difference in total absorption when 13.3 microgram/cm2 was applied as a single dose or when the 13.3 microgram/cm2 was applied three times, totaling 40 microgram/cm2. However, when 40 microgram/cm2 was applied as a single dose, absorption was substantially increased over 13.3 microgram/cm2 applied either once or three times. These results confirm previously reported results done with single versus repetitive doses of hydrocortisone.
Animals↗
[Variations of superficial nerves at the pelvis considering orthopaedic surgical approaches].
PROBLEM: Intraoperative injuries of vessels and nerves are common risks and repeatedly described in orthopaedic pelvic surgery. Especially in pelvic osteotomies or bone harvesting procedures subcutaneous nerves are at risk for damage. In this study we elucidated the variations of subcutaneous nerves by anatomic preparation exposure with regard to the anterior and posterior spines. METHODS: To investigate the different anatomic variations the iliohypogastrical, lateral cutaneous, subcostal and the cluneal nerves of 10 human cadavers were prepared and exposed bilaterally at the anterior, lateral and posterior pelvic region. For determination of anatomically important reference points the distance of these structures to the anterior superior spine was measured and compared with present datas in literature with respect to the ilioinguinal (Letournel) and iliofemoral (Smith- Petersen) approach. RESULTS: We found a high variability of superficial pelvic nerves. Our findings differ somehow with datas of recent papers. CONCLUSION: The findings of our study stress the importance of basic knowledge and thorough preparation in surgical procedures at the pelvis including harvesting bone grafts to minimize donor site morbidity.
Bone Transplantation↗
Intracavernous branches of the internal carotid artery (ICA). Comprehensive review of their variations.
Since we started to work in the lateral sellar region (in 1973), a large volume of angiographic material has provided us with exceptional variations that added to the anatomic facts obtained from our dissections. At present, these anatomic facts remain, but the way we look at them and the way we use them for endovascular treatments, has created a need for a different type of approach and understanding. In this report, we present a flexible anatomical view of the intracavernous branches of the internal carotid artery and a scheme to understand and predict the anatomical variations of these collaterals. Four embryonic vessels play an important role in the variations of the arterial supply to the lateral cavernous region: the dorsal ophthalmic artery, the stapedial artery, the trigeminal artery and the primitive maxillary artery. In general each of them partially regresses leaving behind a remnant. However there is a spectrum from their persistence to incomplete regression, resulting in variations of the supply to their distal territories. The term "meningohypophyseal" should be abandoned because it is misleading and improperly used. Complete agenesis is known for a long time; in case of segmental agenesis of the ICA each of the embryonic vessels presented above may represent an alternate route to bypass the agenesis. The ICA is not a direct feeding artery but a succession of independant segments which can be the site of various anomalies. An embryonic transdural circle can be individualized; it is constituted by the trigeminal arteries posteriorly, the ICA siphon anteriorly, the transsellar anastomosis and internal maxillary artery connections. Although regressions usually occur in this embryonic transdural circle, its derivatives congenital and acquired arterial pathologies. It also constitutes the key system in determining the arterial variations of the perisellar region.
Carotid Artery, Internal↗
Right hepatic duct emptying into the cystic duct: report of a case.
BACKGROUND: Anomalous insertion of the right hepatic duct into the cystic duct is a rare anatomic variation. At this writing, only nine cases have been reported in the literature. In the patients presenting with this anomaly, the surgeon may accidentally transect the right hepatic duct during cholecystectomy. METHODS: We encountered a case of anomalous insertion of the right hepatic duct into the cystic duct, which was clearly demonstrated in the intraoperative cholangiography during laparoscopic cholecystectomy. RESULTS: As the half-cut point of the cystic duct happened to be on the gallbladder side of the cystic duct, cholecystectomy was accomplished laparoscopically. CONCLUSIONS: In anomalous insertion of the right hepatic duct into the cystic duct, hepatic duct transection could happen. Preoperative precise evaluation of the biliary duct, awareness of potential biliary variations, and identification of all anatomic structures before ligation and division were essential to prevent bile duct injury.
Aged↗
A variant of flexor carpi ulnaris causing ulnar nerve compression.
Anatomical variations of the muscles and nerves around the wrist are common. Knowledge of such variations is derived from 2 sources: anatomical dissections and clinically reported cases. We present a case of duplication of the tendon of flexor carpi ulnaris with splitting of the ulnar nerve. The ulnar slip of the tendon was inserted into the pisiform bone and the radial slip into the proximal phalanx of the ring finger. The anatomical literature and the clinically reported cases of variations of the flexor carpi ulnaris are reviewed.
Adult↗
High-resolution random mesh algorithms for creating a probabilistic 3D surface atlas of the human brain.
Striking variations exist, across individuals, in the internal and external geometry of the brain. Such normal variations in the size, orientation, topology, and geometric complexity of cortical and subcortical structures have complicated the problem of quantifying deviations from normal anatomy and of developing standardized neuroanatomical atlases. This paper describes the design, implementation, and results of a technique for creating a three-dimensional (3D) probabilistic surface atlas of the human brain. We have developed, implemented, and tested a new 3D statistical method for assessing structural variations in a data-base of anatomic images. The algorithm enables the internal surface anatomy of new subjects to be analyzed at an extremely local level. The goal was to quantify subtle and distributed patterns of deviation from normal anatomy by automatically generating detailed probability maps of the anatomy of new subjects. Connected systems of parametric meshes were used to model the internal course of the following structures in both hemispheres: the parieto-occipital sulcus, the anterior and posterior rami of the calcarine sulcus, the cingulate and marginal sulci, and the supracallosal sulcus. These sulci penetrate sufficiently deeply into the brain to introduce an obvious topological decomposition of its volume architecture. A family of surface maps was constructed, encoding statistical properties of local anatomical variation within individual sulci. A probability space of random transformations, based on the theory of Gaussian random fields, was developed to reflect the observed variability in stereotaxic space of the connected system of anatomic surfaces. A complete system of probability density functions was computed, yielding confidence limits on surface variation. The ultimate goal of brain mapping is to provide a framework for integrating functional and anatomical data across many subjects and modalities. This task requires precise quantitative knowledge of the variations in geometry and location of intracerebral structures and critical functional interfaces. The surface mapping and probabilistic techniques presented here provide a basis for the generation of anatomical templates and expert diagnostic systems which retain quantitative information on intersubject variations in brain architecture.
Algorithms↗
Clinical and macroscopic study of maxillary molars with two palatal roots.
AIM: To report an anatomical variation in maxillary first molars. SUMMARY: A case report is presented of a maxillary first molar requiring root-canal treatment that had two palatal roots with distinct canals and foramena at the apical level. Root-canal treatment was performed using mechanical instrumentation with NiTi files. An anatomical study on two extracted maxillary second molars with the same variation revealed their internal structure. This case demonstrates an uncommon anatomical condition and supplements previous reports of such cases affecting maxillary molars. KEY LEARNING POINTS: Clinicians should be aware of uncommon anatomical variations in maxillary molars. The majority of maxillary first molars have three roots and four canals. Maxillary molars may have two canals in the palatal root.
Adult↗
Brachial plexus variations in human fetuses.
OBJECTIVE: We examined the anatomic variations of the brachial plexus (BP) in human fetuses. METHODS: This study was performed with 200 BPs from spontaneously aborted fetuses without detectable malformations. The plexuses were dissected, and the normal position and/or morphological variations of the BP were determined and photographed. RESULTS: There were no variations in 93 plexuses, and 107 plexuses were observed to have different variations. Morphological variations were observed more frequently among female fetuses and right sides. The BPs were composed mostly of the C5, C6, C7, and C8 nerves and the T1 nerve (71.5%). A prefixed plexus was observed in 25.5% of cases, and a postfixed plexus was observed in 2.5% of cases. In one case (0.5%), the C4 and T2 nerves joined the formation. The inferior trunk was not formed in 9% of cases. The superior trunk was not formed in 1% of cases. In one plexus, the superior trunk was formed by the ventral rami of the C4 and C5 nerves. In one case, the inferior trunk was formed by the ventral rami of the T1 and T2 nerves. Division variations were observed most frequently. There were also variations in the terminal branches, such as the roots of the median nerve joining in the distal part of the arm (8.5%), the axillary nerve being separate from the posterior division of the superior trunk (2.5%), and a connection existing between the median and musculocutaneous nerves (1%). CONCLUSION: Knowledge of BP variations is important for surgeons who perform surgical procedures in the cervical and axillary regions.
Axilla↗
Magnetic resonance axillography for preoperative diagnosis of the axillopectoral muscle (Langer's axillary arch): a case report.
The axillary arch of Langer is the most common muscular variation in the axilla. Recognition of anatomic variations is important for surgeons to perform safe axillary surgery. We describe a case of a woman with breast cancer, in whom sentinel lymph node biopsy was successfully performed and the presence of this anomaly preoperatively diagnosed by magnetic resonance axillography.
Axilla↗
Cerebral venous sinuses: anatomical variants or thrombosis?
Anatomical variations of the posterosuperior dural venous sinuses and, in particular, the absence or hypoplasia of one of them has been described in several studies. However, no recent detailed analysis on the subject exists. Cerebral venous thrombosis is quite often evoked, although rarely confirmed, when the physician is faced with patients having various neurological problems. In fact, for a number of cases the image interpreted as thrombosis is nothing but the total or partial absence of a dural sinus. It was considered of interest to undertake an anatomical study in order to define these variations. The results of anatomoradiological investigations of 70 fresh cadavers were compared to those obtained by angiographic examination of 100 patients not suffering from any kind of venous pathology (patients explored angiographically for glioma, meningioma or aneurysm). Our conclusions and a review of the embryology literature enabled us to demonstrate that a number of radiological findings, quite often considered pathognomonic of venous thrombosis (i.e. 'delta sign'), are in fact the result of anatomical variations.
Cerebral Veins↗
Systematic anatomy of Erythroxylum P. Browne: practical and evolutionary implications for the cultivated cocas.
Preliminary study of the pantropical Erythroxylaceae indicates that anatomical features can provide valuable insight into the generic, infra-generic and specific affinities of unidentified specimens. Combinations of qualitative and quantitative anatomical data are most reliable when considered in conjunction with relevant ecological and plant morphological data. Extreme caution is advised in such taxonomic applications due to the intergrading patterns of anatomical variation exhibited within the family. Careful consideration must be given to the potential influence on anatomy of factors such as plant age, habit, leaf morphology and environmental conditions. Although a few species of Erythroxylum are identifiable solely on the basis of unique wood anatomical features, the majority of species can be identified only through a combination of morphological and vegetative anatomical features. Closely related species and species of similar habitats are often very similar in their wood and leaf structure. Anatomical differences are more subtle among the cultivated cocas and their closest neotropical relatives than among most taxa of Erythroxylaceae. A typological concept of foliar venation patterns among the cultivated cocas permits the varietal identification of isolated coca leaves. Several neotropical relatives of the cultivated cocas represent potential adulterants in commercial samples of coca leaf as a result of their striking similarity to genuine coca in leaf form, venation and anatomy. Due to the broad and overlapping range of leaf structural variation exhibited among the cultivated cocas and their nearest relatives, identifications of isolated leaves or leaf fragments are ill-advised in the absence of relevant ecological data. Patterns of wood and leaf anatomical variation within the Erythroxylaceae are most readily explicable as the result of evolutionary diversification in plant habit, leaf size, form and relative duration. Significant correlations among wood and leaf structure reveal various "adaptive strategies" among species of Erythroxylaceae. Redundant patterns of structural evolution, evident among the different species and genera of Erythroxylaceae, help to elucidate the probable evolutionary origins of the cultivated cocas. Comparative anatomical data support the hypothesis that Bolivian coca (E. coca) represents the most primitive of the cultivated cocas. The Colombian and Trujillo varieties of coca (E. novogranatense) appear to have been derived from a Bolivian-like ancestral coca as a result of long-term cultivation, geographic isolation and human selection for increased flavor, palatability and drought resistance.
Coca↗
Two methods for flat-mounting cortical tissue.
Two procedures are described which allow cortical grey matter to be unfolded and flattened. Tangential sections of the flat-mounted tissue can reveal clear histological views of horizontal variations in cortical structure and function; these anatomical variations would be hard to see in sections cut by conventional techniques. Examples are presented from non-human primate tissue, but the technique has also been used successfully in a number of other mammalian species, including man. Advantages and disadvantages of the various methods for extracting topographical patterns from the cortex are discussed.
Animals↗
Patent foramen ovale: a review of associated conditions and the impact of physiological size.
Patent foramen ovale (PFO) is implicated in platypnea-orthodeoxia, stroke and decompression sickness (DCS) in divers and astronauts. However, PFO size in relation to clinical illness is largely unknown since few studies evaluate PFO, either functionally or anatomically. The autopsy incidence of PFO is approximately 27% and 6% for a large defect (0.6 cm to 1.0 cm). A PFO is often associated with atrial septal aneurysm and Chiari network, although these anatomic variations are uncommon. Methodologies for diagnosis and anatomic and functional sizing of a PFO include transthoracic echocardiography (TTE), transesophageal echocardiography (TEE) and transcranial Doppler (TCD), with saline contrast. Saline injection via the right femoral vein appears to have a higher diagnostic yield for PFO than via the right antecubital vein. Saline contrast with TTE using native tissue harmonics or transmitral pulsed wave Doppler have quantitated PFO functional size, while TEE is presently the reference standard. The platypnea-orthodeoxia syndrome is associated with a large resting PFO shunt. Transthoracic echocardiography, TEE and TCD have been used in an attempt to quantitate PFO in patients with cryptogenic stroke. The larger PFOs (approximately > or =4 mm size) or those with significant resting shunts appear to be clinically significant. Approximately two-thirds of divers with unexplained DCS have a PFO that may be responsible and may be related to PFO size. Limited data are available on the incidence of PFO in high altitude aviators with DCS, but there appears to be a relationship. A large decompression stress is associated with extra vehicular activity (EVA) from spacecraft. After four cases of serious DCS in EVA simulations, a resting PFO was detected by contrast TTE in three cases. Patent foramen ovales vary in both anatomical and functional size, and the clinical impact of a particular PFO in various situations (platypnea-orthodeoxia, thromboembolism, DCS in underwater divers, DCS in high-altitude aviators and astronauts) may be different.
Aerospace Medicine↗