Ismihan Ilknur Uysal

Brachial plexus variations in human fetuses.

OBJECTIVEWe examined the anatomic variations of the brachial plexus (BP) in human fetuses. METHODSThis 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. RESULTSThere 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%). CONCLUSIONKnowledge of BP variations is important for surgeons who perform surgical procedures in the cervical and axillary regions.

Accessory spleens at autopsy

Accessory spleens (AS) may be formed during embryonic development when some of the cells from the developing spleen are deposited along the path from the midline, where the spleen forms, over to its final location on the left side of the abdomen. An accessory spleen is usually near the spleens hilum, but it may be embedded partly or wholly in the tail of the pancreas. The aim of this study was to investigate the incidence and distribution of AS during routine forensic autopsies. AS were investigated in 720 consecutive autopsy cases. Fifty‐four AS were found in 48 (6.7%) cases. AS were found in hilum of the main spleen in 28 cases, the great omentum in 13 cases, the pancreas in 5 cases, and the pelvis in 2 cases. There were two AS in two cases and three AS in another two cases. Awareness of the possible presence of AS is important because when splenectomy is performed for some conditions such as immune thrombocytopenic purpura, failure to remove the AS may result in the failure of the condition to resolve. Additionally, during medical imaging, AS may be confused for enlarged lymph nodes or neoplastic growths. In conclusion, autopsy series are useful for determining the incidences and the other features of AS in different populations, in addition to those studies using CT scans and those studies obtained during laparoscopic or open surgeries. Clin. Anat. 24:757–762, 2011.

The course and variations of the branches of the musculocutaneous nerve in human fetuses

The course and branches of the musculocutaneous nerve (MCN) were dissected in 140 human fetal arms. The MCN entered the superior, middle, and inferior part of coracobrachialis in 43%, 37%, and 17% of arms, respectively, and the remaining 3% did not pierce coracobrachialis. The motor branches to biceps were classified as follows: Type 1 (83.6%): a single branch that bifurcated to supply the two heads of biceps; Type 2 (14.3%): two separate branches each innervating one head of biceps; Type 3 (2.1%): a single branch that bifurcated to supply each head of biceps plus an additional branch that innervated the distal part of biceps. The motor branches to brachialis were classified as follows: Type 1 (93.6%): a single branch to brachialis; Type 2 (6.4%): a single branch that bifurcated into two branches both supplying brachialis. Communications between the MCN and the median nerve (MN) were observed in 10% of specimens, of which three types (A, B, C) could be identified depending on their origin and union. In the most frequently observed type (B, 50% of cases) the communicating branch arose from the proximal part of the MCN and joined the MN in the middle or distal part of arm. The data presented here will be of use to surgeons, especially pediatric surgeons who undertake surgical procedures in the axilla and arm. Clin. Anat. 22:337–345, 2009.

The motor branches of median and ulnar nerves that innervate superficial flexor muscles: a study in human fetuses

PurposeWe aimed to describe the distribution of the motor branches of the median and ulnar nerves that innervate the superficial flexor muscles in detail, as well as to determine any communication between these two nerves in a series of 100 human fetuses.MethodsThis study was performed on 200 upper limbs from 100 fetuses. However, the motor branches of the median nerve were determined on 50 upper limbs because of the developmental properties of medial epicondylar muscles.ResultsThe motor branch, which innervates the pronator teres, is classified into two types and four subtypes. The flexor carpi radialis branch arose as a single branch in 30% of the cases. The innervation of the flexor digitorum superficialis was also performed by a single muscular branch in 88% of the cases and by two branches in 12% of the cases. The ulnar nerve was classified into two types according to the number of muscular branches in the forearm. Martin–Gruber anastomosis was observed in 7.5% of the cases.ConclusionsThese results show differences from classical definitions regarding the muscular branching patterns of the median and ulnar nerves. We suggest revisiting the classical descriptions of innervation patterns of pronator teres, palmaris longus and flexor carpi radialis muscles, since the variations observed in their innervation patterns are more diverse than has been described.

Communications between the palmar digital branches of the median and ulnar nerves: A study in human fetuses and a review of the literature†

In this study, median nerves (MNs) and ulnar nerves (UNs) were dissected in 200 palmar sides of hands (left and right) of 100 (50 male, 50 female) spontaneously aborted fetuses with no detectable malformations. The fetuses, whose gestational ages ranged from 13 to 40 weeks, were dissected under an operating microscope. The MN divided first into a lateral ramus and a medial ramus and then formed a common digital nerve. The first common digital nerve trifurcated in all of the studied cases. The branching patterns were classified into two types (Type 1 and Type 2) based on the relationship with the flexor retinaculum (behind/distal of it). A communication branch between the UNs and MNs in the palmar surface of the hand was found in 59 hands (29.5%). The proper palmar digital nerves were numbered from p1 to p10, starting from the radial half of the thumb to the ulnar half of the little finger, and these nerves exhibited six types of variations. The present data obtained from human fetuses will aid in elucidating the developmental anatomy of the nervous system and provide hand surgeons with a more complete anatomical picture to help them to avoid iatrogenic injuries. Clin. Anat. 23:234–241, 2010.

Investigation of Developmental Toxicity and Teratogenicity of Macrolide Antibiotics in Cultured Rat Embryos

Macrolides are considered to be one of the safest anti‐infective groups in clinical use, with severe adverse reactions being rare. However, there are limited data about their embryotoxicity and teratogenicity. We aimed to investigate and compare the effects of these agents on embryonic growth and development. Rat embryos were cultured in vitro for 48 h in rat serum. Whole rat serum was used as a culture medium for the control group while different concentrations of spiramycin and azithromycin (1.25–6.25 μg/ml), and clarithromycin (2.5–30 μg/ml) were added to rat serum for the experimental groups. Dose‐dependent effects of macrolides on embryonic developmental parameters were compared using morphological methods. Embryos were evaluated for the presence of any malformations. After morphological examination of the embryos, total DNA was extracted from the cells using standard procedures to determine fragmentation of nuclear DNA of embryonic cells. When compared with the control embryos, the macrolides significantly decreased all growth and developmental parameters dose dependently. While clarithromycin was found to cause more developmental toxicity than spiramycin and azithromycin, azitromycin was determined to have more teratogenicity potential. Compared with controls, there was no difference regarding the fragmentation of nuclear DNA of all the agents used. According to these results, when the toxic and teratogenic potential of the used agents compared, because of the lower toxic and teratogenic effects observed with spiramycin, this agent may be preferred for parturients.

Unilateral Variations of Vessels and Nerves in the Neck

Durante una diseccion de rutina, fue obserada en el lado izquierdo del cuello de un cadaver de sexo masculino de 65 anos de edad variaciones anatomicas vasculares y nerviosas. Se observo que el tronco linguofacial se originaba de la arteria carotida externa y que la arteria faringea ascendente se origina en la arteria occipital. Se determino que los ramos laringofaringeos originadas desde el ganglio cervical superior, giraban en torno al origen de la arteria tiroidea superior. Como una variacion adicional, la vena jugular interna se encontro dividida. El asa cervical y el vientre inferior del musculo omohioideo pasaban a traves de las partes de la dividion de la vena. Creemos que este tipo de variaciones supone dificultades importantes durante procedimientos radiologicos y quirurgicos de la region del cuello, y por tanto, es importante que los cirujanos conozcan estas variaciones.

Investigation of Direct Toxic and Teratogenic Effects of Anticoagulants on Rat Embryonic Development Using In Vitro Culture Method and Genotoxicity Assay

Heparin and low molecular weight heparins (LMWHs) are used to reduce the incidence of venous thromboembolism in pregnancy. Although, these agents have been shown to be safe when used during pregnancy, the studies about direct toxic and teratogenic effects of these drugs on embryonic development are limited. In this study, the effects of heparin and LMWHs on rat embryonic development were investigated by using in vitro embryo culture and micronucleus (MN) assay methods. Rat embryos were cultured in vitro in the presence of different concentrations of heparin (5–40 IU/ml), dalteparin (2.5–20 IU/ml), enoxaparin (25–100 μg/ml) and nadroparin (1–4 IU/ml). Effects of anticoagulants on embryonic developmental parameters were compared and embryos were evaluated for the presence of any malformations. After culturing the embryos, classic MN assay was performed. Anticoagulants significantly decreased all growth and developmental parameters dose‐dependently. Dalteparin and enoxaparin were found to cause more developmental toxicity than heparin and nadroparin. Along with haematoma in general, heparin and nadroparin caused maxillary deformity, situs inversus and oedema most frequently, while neural tube defects were observed with dalteparin and enoxaparin. All agents also significantly induced MN formation in rat embryonic blood cells. These results indicate the possible genotoxic effects of anticoagulant agents on the developing rat embryo when applied directly.

Anatomical Examination of the Foramens of the Middle Cranial Fossa

Tres foramenes pueden ser identificados en el ala mayor del esfenoides: El foramen redondo (FR), foramen oval (FO) y el foramen espinoso (FS). Puede ademas existir otro foramen llamado foramen oval accesorio o foramen de Vesalio (FV), que conecta la fosa craneal media a la fosa pterigoidea. Se describe como una abertura con paredes lisas por anterior y medial al foramen oval, que conduce a un canal oblicuo dirigido hacia la fosa pterigoidea. FV estuvo presente entre FO y FR en 14 (31,8%) de 44 craneos secos y 6 (33,3%), en 18 lados en la base de craneos de cadaveres (total 20 (32,3%) de 62). El diametro de los foramenes en los lados derecho e izquierdo se observo casi simetricos. Las distancias de FR desde la linea mediana en el lado izquierdo fue mayor que en el lado derecho. Ademas, la distancia entre FO y el vertice de la porcion petrosa y la distancia entre el FS y el vertice porcion petrosa fueron mayores en el lado izquierdo. En el lado derecho la distancia entre A y FR, asi como la distancia entre A y FS fueron mayores. Por otra parte, la distancia entre los FR y el vertice del porcion petrosa fue mayor en el lado derecho. Las variaciones anatomicas en el tamano de la apariencia y la distancia de FR, DE, FS y FV son de gran importancia quirurgica. Podemos inferir que la informacion proporcionada en este estudio puede ayudar al neurocirujano y anatomista para aumentar el conocimiento sobre la anatomia de la fosa craneal media.

Investigation of Developmental Toxicity and Teratogenicity of Antiemetics on Rat Embryos Cultured In Vitro

In this study, we aimed to investigate and compare the direct toxic and teratogenic effects of dimenhydrinate, metoclopramide and trimethobenzamide HCl, antiemetic drugs on embryonic growth and development in cultured rat embryos. Embryos were explanted on day 9.5 of gestation and cultured. Whole rat serum was used as a culture medium for the control group while different concentrations of dimenhydrinate (2.5–20 μg/ml), metoclopramide (10–50 μg/ml) and trimethobenzamide HCl (25–100 μg/ml) were added to serum for the experimental groups. Effects of antiemetics on embryonic developmental parameters were compared, and embryos were evaluated for the presence of any malformations. Also, the total DNA was extracted from the cells to determine the fragmentation of nuclear DNA of embryonic cells. Compared with the control embryos, the antiemetics significantly decreased all growth and developmental parameters dose dependently. There was no difference regarding the fragmentation of nuclear DNA of the all used agents and controls. Amongst the agents, trimethobenzamide HCl was found to have more toxic and teratogenic potential, and metoclopramide appears to be the least toxic antiemetic and therefore could be more safely used and might be preferred for the treatment of nausea and vomiting in pregnancy.