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PubMed2001

Females have lower skin surface pH than men. A study on the surface of gender, forearm site variation, right/left difference and time of the day on the skin surface pH.

BACKGROUND/AIMS: It is of great interest to describe the many functions and properties of the skin in order to better understand reactions that result in different skin abnormalities, as a prerequisite in the development of skin products and topical medicines. Skin surface pH is considered a critical parameter of skin wellbeing and is typically studied on the forearm skin. Despite many previous investigations, this is an extensive field that still needs a great deal of research. The aim of our study was to investigate gender related differences, differences between right and left arms, anatomical variation and daytime variation in skin surface pH. METHODS: Skin surface pH was measured on the flexor surface of the forearm on eleven healthy volunteers (6 men and 5 women). A Mettler Toledo pH meter (pH meter 1140) was used. The subjects were measured once every hour from 8 a.m. to 3 p.m. in five areas from the elbow to the wrist. In each of the five areas, three measurements were performed next to each other, and the mean of these was used in subsequent calculations. RESULTS: A statistically significant difference in skin pH between men (mean pH=5.80) and women (mean pH=5.54) was found, with women being more acidic than men (P<0.01). No difference between right and left arm was found. In men, the area closest to the wrist had significantly lower pH values compared with the proximal sites. This was not the case in women. Skin surface pH decreased during normal working hours in both genders. CONCLUSION: Spontaneous skin surface pH was found to be significantly lower in women, as compared to men--albeit, the difference was small and of unknown relevance. Nevertheless, comparative studies on skin surface pH should be balanced with respect to gender. There appeared to be no right/left difference and no systematic change during the working day. Also, measurements should not be conducted close to the wrist.

Female↗

PubMed1993

Laparoscopic anatomy of the biliary tree.

A thorough knowledge of the anatomy of the extrahepatic biliary tree and its frequent anatomic variations is essential for performance of a safe laparoscopic cholecystectomy. The surgeon should have an appreciation for the distortions in the anatomy as a result of retraction on the gallbladder and how the direction of retraction alters the spatial relationships between the cystic duct and common bile duct. The steps in the operative procedure have been outlined to provide good exposure and optimize the identification of structures. Good exposure will enable the surgeon to identify anatomic variants; however, a thorough knowledge of these variants is necessary for safe performance of the operation.

Biliary Tract↗

PubMed1980

Technical dilemmas in portacaval shunt operations as a consequence of replaced right hepatic artery.

Surgical procedures designed to decompress the portal venous system in patients with cirrhosis and bleeing esophageal varices may be complicated by anatomic variations in the extrahepatic arterial circulation. Anomalous right hepatic arteries which arise from the superior mesenteric artery may be encountered in 18 to 20 per cent of the normal population. Replaced arteries are not accessory vessels but rather provide the sole arteries circulation to well defined segments of the liver. Unfortunate injury may result in severe ischemic truama of the liver. Preoperative vicseral arteriography is essential prior to any contemplated portosystemic shunt procedure. The unusual anatomic relationship of such an anomalous right to hepatic artery to the portal vein may contraindicate standard portacaval, interposition portacaval or portarnal shunt procedures; graft angulation and anastomotic distortion may jeopardize shunt patancy and result in recurrent variceal hemmorrhage. A technique for portal vein-hepatic artery transposition and end-to-side portacaval shunt is presented as a feasible alternative if anomalies of the hepatic artery preclude standard shunt procedures.

Hepatic Artery↗

PubMed2006

Non-developed external oblique aponeurosis in inguinal hernia repair: a case report and discussion of the literature.

Open inguinal hernia repair is one of the most commonly performed operations in the world. It relies heavily on the presence of an inguinal canal formed by the external oblique aponeurosis and conjoint tendon. Variations of the anatomy of this region are rarely described. We describe a patient with bilateral inguinal hernias and missing external oblique aponeurosis. The patient underwent open repair secondary to previous abdominal surgery and the inability to obtain laparoscopic access. A medline search was performed and we provide a synopsis of the literature. At operation, no clear external oblique aponeurosis could be identified and large defects of the transversalis fascia were corrected. CT images of the anatomic variations are provided. To the best of our knowledge, combined abnormalities of the external oblique aponeurosis and transversalis fascia have not been described before.

Abdominal Wall↗

PubMedDate not supplied

A primer of primate pathology: lesions and nonlesions.

Nonhuman primates are important laboratory animals for biomedical, pharmacology, and toxicology research. To effectively use primates as models, their gross and histologic anatomy, physiology and natural history, as well as common health problems and the source from which the primate is obtained, must be known and understood by pathologists involved in study design and/or interpretation. The first very important lesson in the "primer" is: there is no such thing as a generic monkey. Brand names (ie, species and subspecies) are important. Several taxonomic groups of primates are used in research including: prosimians, such as galagos and lemurs; New World monkeys, particularily marmosets; Old World monkeys, especially macaques and baboons; and the chimpanzee, an African ape. Differences between taxa are exemplified by the glucocorticoid resistance of New World monkeys compared to Old World monkeys, which results in the requirement for Vitamin D3 and their high circulating levels of steroids such as cortisone and progesterone. Differences in ovarian histology between Old and New World monkeys probably relate to steroid receptor biology as well. There are also variations in disease manifestations, even among closely related primate species such as rhesus and cynomolgus macaques (cynos). For example type D retrovirus infection is accompanied by lymphomas in cynos, but not rhesus. The second important lesson in this "primer" is: "not test article related" does not always mean "normal." Lymphoid nodules in bone marrow or salivary gland, a common background finding in macaques, often signal the presence of type D retrovirus. Other histologic changes and normal anatomic variations may be confusing to individuals not routinely examining primate tissues. The objective of this paper is to familiarize pathologists with the use of primates in research as well as lesions and nonlesions (normal anatomy or physiology) of primates that may influence study design and confound interpretation.

Animal Diseases↗

PubMed2002

[Anatomical and surgical study of the medial calcaneus branch of the tibial nerve].

To better understand the anatomical variations of the medial calcaneus branch, the tibia nerve were dissected in 20 ankles of fresh black African cadavres. The medial calcaneus branch which is a collateral branch of tibial nerve was constant. It was unique in 80% of cases and was detaching itself from the trunck of the tibial nerve ot the entrance of the calcaneal sulcus. It was in the form of two small nerves with point of departure from the common tibial nerve trunk. These anatomic constatations confronted with those published in literature permits us to understand the etiopathogenic aspects of certain neuropathies of the ankles. To add this they impose a certain order if precaution in the operational surgnical route of the posterior section of the ankle.

Ankle↗

PubMed2002

[Anatomical and surgical study of the medial calcaneus branch of tibial nerve].

To better understand the anatomical variations of the medial calcaneus branch, the tibia nerve were dissected in 20 ankles of fresh black African cadavers. The medial calcaneus branch which is a collateral branch of tibial nerve was constant. It was unique in 80% of cases and was detaching itself from the trunk of the tibial nerve at the entrance of the calcaneal sulcus. It was in the form of two small nerves with point of departure from the commun tibial nerve trunk. These anatomic constatations confronted with those published in literature permits us to understand the etiopathogenic aspects of certain neuropathies of the ankle. To add this they impose a certain order if precautions in the operational surgical route of the posterior section of the ankle.

Duplicate Publications as Topic↗

PubMed1999

Clinical and radiological evaluation following surgical treatment of condylar neck fractures with lag screws.

It was the purpose of this study to evaluate the outcome of lag screw osteosynthesis in severely displaced fractures or fracture dislocations of the mandibular condyle as well as intra- and postoperative complications of this technique. From 1980 to 1996 a total of 492 patients with condylar fractures were treated with lag screw osteosynthesis. Clinical and radiological follow-ups were carried out in 230 patients with severely displaced fractures or fracture dislocations of the mandibular condyle. The period between surgery and follow-up was between 6 months and 2 years. The majority of the clinical results were satisfactory presumably due to the anatomically exact reduction of the fragment (93.4%). Extreme anatomic variations of the mandible (5.8%) and incorrect application of the technique (8.8%) resulted in reduced functional stability of lag screw osteosynthesis. Insufficient fragment reduction and postoperative complications (such as wound infection) entailed restriction of mandibular mobility and arthrotic deformations were seen as persistent radiological irregularities of the mandible. It has been possible to avoid complications and to achieve favourable functional results in complicated fractures of the mandibular condyle by applying strict indications for lag screw osteosynthesis and by considering the individual anatomical peculiarities.

Adolescent↗

PubMed1999

[Sagittal changes induced by knee arthroplasty: a radiologic study].

PURPOSE OF THE STUDY: To quantify the modifications occurring on the femoral side, after Total Knee Arthroplasty, we describe a method of measurements in the sagittal plane on standardized X-rays. MATERIAL AND METHODS: We report the clinical and radiologic results of a prospective study of 80 cases of Total Knee Arthroplasty performed with the same prosthesis. We eliminated twenty cases with incorrect X-rays. Measurements were done on 60 preoperative X-rays and 60 postoperative X-rays. The aim of the measure was to quantify the modifications induced by the prosthesis on the trochlear groove and on the tibio-femoral joint line in full extension and in flexion, to eliminate individual femoral diameter was used as a reference in order to cancel variations in X-rays magnification. We first validated the two perpendicular reference axis on which we based all the measurements. RESULTS: No significative difference was found on the position of the tibio-femoral joint line in flexion. The tibio-femoral joint line in extension was significantly moved distally. The prosthesis was placed too distally, therefore we changed the operative procedure. No significative difference was found on the position of the anterior trochlear groove. DISCUSSION: With this method, the anatomic variations of the femoral profiles can be quantified, therefore, further prosthesis shapes can be improved. Radiological follow-up of knee prosthesis and comparison of the influence of different prosthesis can be made by these measures.

Aged↗

PubMedDate not supplied

Morphological variations of the lung fissures and lobes.

BACKGROUND: Knowledge of the position of fissures of the lungs is necessary for the appreciation of lobar anatomy and thus locating the bronchopulmonary segments. METHODS: Morphological variations of fissures and lobes of the lungs were studied in 30 pairs of lungs from cadavers. RESULTS: Five right-sided lungs showed absence of horizontal fissure, 19 showed incomplete horizontal fissure. Eleven right-sided and 14 left-sided lungs showed incomplete oblique fissure and two right-sided lungs showed both absence of horizontal fissure and an incomplete oblique fissure. Accessory fissure was seen in three left-sided and one right-sided lungs. CONCLUSIONS: Awareness regarding anatomical variations is essential for performing lobectomies and segmental resection and interpreting radiological images.

Dissection↗

PubMed2003

Variations in the anatomy of the inferior alveolar nerve.

Variations in the anatomy of the inferior alveolar nerve were seen in 2 of the 20 dissections of the infratemporal fossa in 10 cadavers. A connecting nerve branch that originated from the auriculotemporal nerve joined the inferior alveolar nerve on both sides. The second part of the maxillary artery passed between the mandibular nerve, the root of the inferior alveolar nerve, and the connecting nerve branch which formed a loop. The maxillary artery seemed to be entrapped. Neurovascular entrapment can cause pain and numbness. Anatomical variations in this region should be kept in mind, particularly in cases of failed treatment of trigeminal neuralgia.

Aged↗

PubMed1997

Intravenous cholangiography before 1000 consecutive laparoscopic cholecystectomies.

BACKGROUND: The advent of laparoscopic cholecystectomy has resulted in an increase in common bile duct (CBD) injuries. Routine intraoperative cholangiography has been advocated to prevent these injuries. This study describes an alternative management strategy applied to a consecutive series of 1000 patients having laparoscopic cholecystectomy. METHODS: In patients with no history of contrast allergy and no suspicion of CBD stones, preoperative intravenous cholangiography (i.v.c.) was performed routinely. Patients with suspected or detected CBD stones were referred for endoscopic retrograde cholangiography. This strategy was supplemented by selective intraoperative cholangiography. RESULTS: Overall 782 of the 1000 patients had successful preoperative i.v.c., allowing detection of 30 CBD stones and providing useful information about anatomical variation in CBD anatomy. Patients with inconclusive i.v.c. studies, or those with a history of contrast allergy, had intraoperative cholangiography, which demonstrated a further 19 CBD stones. There were no contrast reactions and no damage to the biliary system which might have been obviated by intraoperative cholangiography. In the 724 patients who did not require complimentary intraoperative cholangiography, there has been no clinical evidence of missed CBD stones. CONCLUSION: Routine preoperative i.v.c., with reservation of intraoperative cholangiography for indeterminate i.v.c. examinations or the need for anatomical clarification, is a safe strategy for laparoscopic cholecystectomy.

Cholangiography↗

PubMed1988

Imaging contribution to temporal bone anatomy.

The research programme at the Department of Otoradiology, Uppsala, has been directed towards radio-anatomic investigation of various structures of the temporal bone, such as the jugular fossa, the facial canal, the aqueducts, the internal acoustic meatus, and the extent of pneumatization. Deep-frozen temporal bone specimens have been examined by CT and multidirectional tomography in different projections. After that plastic casts have been prepared. The method allows assessment of the anatomic variations of the structures under study, and also an estimate of the reliability of radiographic reproduction. The resolution capability of CT allows satisfactory reproduction of both inner and middle ear structures. Of the ossicles the malleus and incus with their ligaments are regularly visualized. On rare occasions even the stapes can be reproduced.

Humans↗

PubMedDate not supplied

In vitro and in vivo MR imaging of hyaline cartilage: zonal anatomy, imaging pitfalls, and pathologic conditions.

Hyaline cartilage plays an essential role in the maintenance of normal synovial joint function by reducing friction and distributing loads. Histologic analysis of hyaline cartilage reveals zonal variation in cellular morphology, proteoglycan concentration, and collagen fiber size and orientation. High-resolution magnetic resonance (MR) imaging reveals an analogous laminar anatomy that is often visible on clinical images obtained with proper attention to technique. In vitro and in vivo pulse sequences show three distinct laminae: a hypointense superficial lamina, a hyperintense intermediate lamina, and a heterogeneous deep lamina that consists of alternating hyperintense and hypointense bands perpendicular to the subchondral bone. Imaging pitfalls include magic angle effects, truncation artifact, partial volume effect, regional anatomic variation, chemical shift, and magnetic susceptibility effects. Pathologic conditions that affect articular cartilage include chondromalacia patellae, osteoarthritis, and localized traumatic lesions. Although detection of early cartilage disease remains elusive, MR imaging can demonstrate intermediate and advanced lesions.

Adult↗

PubMed1991

De Quervain's syndrome: surgical and anatomical studies of the fibroosseous canal.

Anatomical variations of the first dorsal fibroosseous compartment were studied in 70 patients (38 women, 32 men) who underwent surgical release of the tendons. Seventy-one dissected forearms were also studied. De Quervain's tenosynovitis was the only diagnosis for two thirds of the patients. Nonoperative treatment for all of these patients failed. Forty-three patients (61%) had job-related symptoms. Recovery ranged from 3 to 36 months postoperatively (mean: 4.5 months). Multiple subcompartments were recorded in 47% of patients and in 75% of anatomic specimens. In 94% of the specimens, the abductor pollicis longus (APL) tendon had two to four slips, but in only two were there multiple extensor pollicis brevis (EPB) tendons. Surgeons must recognize that multiple APL tendon slips and two subcompartments are the rule, rather than the exception, in normal anatomy.

Adolescent↗

PubMed2000

The scaphotrapezio-trapezoidal joint. Part 1: An anatomic and radiographic study.

To evaluate anatomic variations and distribution of degenerative changes in the scaphotrapezio-trapezoidal (STT) joint, 165 embalmed cadaver wrists were examined. An interfacet ridge on the distal scaphoid was found in 81% of the wrists and the shape of the distal joint surface of the scaphoid was classified into 3 types. Underdevelopment of the capitate-trapezium ligament was found in 15% of the wrists. A new skeletal measurement for the inclination of the joint surface of the trapezium-trapezoid in the STT joint (TT inclination) was investigated anatomically and radiographically. Degenerative changes were found in 39% of the wrists. The most common location of degenerative changes was on its ulnar aspect on the distal scaphoid and on the radial and central aspect of the trapezoid on the TT side. The presence of degenerative changes had a significant correlation with a higher anatomic and/or radiographic TT inclination and/or underdevelopment of the capitate-trapezium ligament.

Adult↗

PubMedDate not supplied

Detection and mapping of abnormal brain structure with a probabilistic atlas of cortical surfaces.

PURPOSE: We have devised, implemented, and tested a technique for creating a comprehensive probabilistic atlas of the human cerebral cortex, based on high-dimensional fluid transformations. The goal of the atlas is to detect and quantify subtle and distributed patterns of deviation from normal cortical anatomy, in a 3D brain image from any given subject. METHOD: Given a 3D MR image of a new subject, a high-resolution surface representation of the cerebral cortex is automatically extracted. The algorithm then calculates a set of high-dimensional volumetric maps, fluidly deforming this surface into structural correspondence with other cortical surfaces, selected one by one from an anatomic image database. The family of volumetric warps so constructed encodes statistical properties of local anatomical variation across the cortical surface. Additional strategies are developed to fluidly deform the sulcal patterns of different subjects into structural correspondence. A probability space of random transformations, based on the theory of anisotropic Gaussian random fields, is then used to encode information on complex variations in gyral and sulcal topography from one individual to another. A complete system of 256(2) probability density functions is computed to reflect the observed variability in stereotaxic space of the points whose correspondences are found by the warping algorithm. Confidence limits in stereotaxic space are determined for cortical surface points in the new subject's brain. RESULTS: Color-coded probability maps are generated, which highlight and quantify regional patterns of deformity in the anatomy of new subjects. These maps indicate locally the probability of each anatomic point being as unusually situated, given the distributions of corresponding points in the scans of normal subjects. 3D MRI volumes are analyzed, from subjects with clinically determined Alzheimer disease and age-matched normal subjects. CONCLUSION: Applications of the random fluid-based probabilistic atlas include the transfer of multisubject 3D functional, vascular, and histologic maps onto a single anatomic template, the mapping of 3D atlases onto the scans of new subjects, and the rapid detection, quantification, and mapping of local shape changes in 3D medical images in disease and during normal or abnormal growth and development.

Aged↗

PubMed1998

Localization of the central sulcus and adjacent sulci in human: a study by MRI.

Variations in localization of the central sulcus and the sulci around the central sulcus namely the superior frontal sulcus, precentral sulcus, postcentral sulcus, marginal ramus of cingulate sulcus were studied in vertex sections retrospectively by magnetic resonance imaging (MRI) method in 3580 cases. Out of total number of cases, 1000 who did not show any macroscopic intracranial pathology were carefully selected for research. Additionally, 0-1 age group was excluded from the study because the sulci develop in first year of postnatal life, excluding the possibility of considering these as anatomical variations. Thus, the total number of cases is decreased to 990. 16 variations related to localization of the superior frontal sulcus, precentral sulcus, central sulcus, postcentral sulcus and the marginal ramus of the cingulate sulcus were identified. The asymmetries of the sulci, the most variable sulci and the distribution of the variations according to sex were statistically analysed.

Adolescent↗