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Biomedical subjects

M Seker

Publications and source records attributed to M Seker.

11 recordsLinked to original sources
PubMed2005

A morphometric study and variations on the lumbar arteries of human fetuses.

Lumbar arteries are in series with the posterior intercostal arteries. The aim of this study has been to investigate the morphometric data on the abdominal aorta of the human fetus and define different types of origin variations of the lumbar artery. Initially, the latex solution colored with red ink was injected into the thoracic aorta. The abdominal aorta and its branches were dissected and examined bilaterally in 120 fetuses (ranging between 16 and 32 post-menstrual weeks) and the anatomic variations recorded. Fourteen fetuses with variations were studied and photographed. The origins and morphologic variations of the lumbar arteries were defined and classified. The morphological relationship of the lumbar arteries to the abdominal aorta and the length and width (diameter) of the vessels were investigated by performing measurements using a digital calliper (mm). The frequency and the types of the different variations determined in the present study have been listed. Abdominal aortic branches and Lumbar artery aneurysms are rare lesions with potentially life-threatening consequences and they are difficult to access anatomically and formidable to manage operatively. During the performance of conventional or open surgical replacement of an abdominal aortic aneurysm with prosthetic grafts, the surgeon needs precise knowledge of the anatomy of the abdominal aortic branches and immediate retroperitoneal structures. The variations on the lumbar arteries may have clinical importance. When this region is under diagnostic and/or surgical investigation using computed tomography scan or diagnostic angiography, the possibility of these variations should be take into consideration to avoid complications.

Aorta, Abdominal↗
PubMed2003

Maxillary-to-petrous internal carotid artery bypass: an anatomical feasibility study.

The possibility for maxillary artery (MA) to petrous internal carotid artery (ICA) bypass was investigated. Five adult cadavers were dissected bilaterally. After zygomatic arch osteotomy, the coronoid process was sectioned at its base. An extensive infratemporal craniotomy was performed at the level of foramina ovale, rotundum and spinosum. The petrous portion of the ICA was exposed by drilling away the floor of the middle fossa, posterior to the foramen ovale and medial to the foramen spinosum. The MA was identified medial to the infratemporal crest and was followed in the pterygopalatine fossa, then transected at the origin of the infraorbital artery. The MA graft was brought posteromedially to reach the petrous ICA. The mean caliber of the MA before the origin of the infraorbital artery was 2.54+/-0.31 mm, 2.76+/-0.14 mm at the site of anastomosis, and 3.46+/-0.32 mm after giving off the middle meningeal artery. The average length of the MA between the middle meningeal artery and the infraorbital artery was 43.4+/-2.35 mm, and up to the site of anastomosis was 37.64+/-1.68 mm. We conclude that the length and diameter of the MA are sufficient for a tension-free anastomosis between MA and petrous ICA, and such a procedure could be used in the treatment of patients with tumors of the infratemporal fossa invading the high cervical ICA.

Anastomosis, Surgical↗
PubMed2001

An investigation of the conus medullaris termination level during the period of fetal development to adulthood.

The spinal cord fills the length of the vertebral canal at the early period of intrauterine term. It is reported to extend to the level of the third lumbar vertebra at birth, because the vertebral column is growing more rapidly in the longitudinal direction than the spinal cord. The present investigation aimed to determine the changes in the termination level of conus medullaris (TLCM) from fetus to adulthood in a total of 285 individuals who had no defects in the central or peripheral nervous system, and were obtained from our Faculties of Medicine and Konya Maternity Hospital between 1992-1995. The age distribution was as follows: 36 fetuses, 20 prematures and 50 neonates, 51 children aged 1 to 7 years and 128 adults aged 15 to 68 years. In this study, for fetuses, prematures, neonates and children the TLCM was determined using ultrasonography. In addition, microdissection was used in fetuses to confirm the results obtained from the above technique. Also, magnetic resonance imaging was used in adults. During fetal life the end of the conus altered its levels from S5 to L3 vertebrae. The tip of the conus medullaris of the prematures and neonates ranged from L1 to L3 vertebrae. The tip of the conus medullaris in the children lay between the Th12 and L3 vertebrae, and in the adults it was between the Th12 and L2 vertebrae. There were slight differences between the prematures and neonates in terms of the TLCM. We concluded that there are differences in the TLCM between the age groups and therefore, especially in prematures and infants the determination of the tip of conus medullaris might be important for preventing postoperative neurological complications.

Adolescent↗
PubMed2000

An investigation of the conus medullaris and filum terminale variations in human fetuses.

The morphologic structure of the conus medullaris and filum terminale was investigated by dissection in 123 human fetuses, obtained from Selçuk University, Faculty of Medicine and Maternity hospital of Konya between 1992-1995. In 78 fetuses, the conus medullaris and filum terminale had a normal morphologic aspect, whereas there was a slight depression or groove formation in the closure region of the caudal neuropore in 45 fetuses. In 15 fetuses, important malformations of the cranium and vertebral column were observed. The morphologic aspects of the conus medullaris in 30 fetuses were abnormal in shape and position, among them 24 fetuses had an abnormal filum terminale (grooved, depressed, thickened or duplicated) whereas it was normal in 6. Deficiency of closure of the caudal neuropore was considered to have a negative effect on the fetal development of the filum terminale.

Cadaver↗
PubMed2000

The relationship between the lumbosacral enlargement and the conus medullaris during the period of fetal development and adulthood.

The spinal cord is situated within the vertebral canal by the third month of intrauterine life. The spinal cord possesses two symmetrical enlargements, which constitute the segments of the plexuses: the cervical enlargement for the brachial plexus and the lumbosacral enlargement for the lumbar and sacral plexus. In our study, we aimed to investigate the relationship between the termination level of the lumbosacral enlargement (TLLE) and that of the conus medullaris (TLCM) during the period of fetal development and adulthood. We used a total of 75 cases: 25 fetuses (male: 16, female: 9) whose crown-rump length ranged between 90-190 mm, 25 premature and full-term neonates (male: 17, female: 8) whose post-menstrual ages ranged between 33-55 weeks, and 25 adults (male: 12, female: 13) aged between 22-72 years. The dissection technique for fetuses, ultrasonography for premature and full-term newborns, and magnetic resonance imaging (MRI) for adults were used to determine lumbosacral enlargement and TLCM. The differences between the TLCM and the termination level of the largest part of the transverse diameter of the lumbosacral enlargement were investigated. The differences between the TLLE and TLCM were found in different ratios from the period of fetal development to adulthood. Therefore, during medical treatment and surgical procedures this should be taken into account to avoid complications.

Adult↗
PubMed2000

The effects of splenic artery ligation in an experimental model of secondary hypersplenism.

OBJECTIVE: To induce hypersplenism in rats by splenic vein ligation and to investigate the effects of splenic artery ligation in this model. BACKGROUND: Selective arterial embolisation and splenic artery ligation (SAL) are used in the treatment of secondary hypersplenism in some medical centres but these methods are not common. MATERIALS AND METHODS: Thirty male Saprague-Dawley rats were allocated to three groups (n = 10). The first group underwent laparotomy, the second and third groups underwent laparotomy and splenic vein ligation. At the end of the third week, laparotomy was performed in the first and second groups and splenic artery ligation in the third group. Erythrocyte, leukocyte and platelet counts were performed weekly. At the end of the sixth week, the animals were sacrificed and the spleens were taken for histopathologic examination. RESULTS: In the second and third groups, after splenic vein ligation, the erythrocyte and platelet counts were significantly reduced at the end of the second week (p < 0.01). In the second group, which underwent splenic vein ligation only, the levels remained low throughout the experiment. In the third group, after splenic artery ligation, there were rises in both erythrocyte and platelet counts; the levels were similar to the levels in the control group at three weeks after splenic artery ligation (p > 0.05). No significant changes were observed in the leukocyte counts throughout the experiment (p > 0.05). CONCLUSIONS: Splenic vein ligation successfully induces experimental secondary hypersplenism. This state can be ameliorated by splenic artery ligation.

Animals↗
PubMed1999

The possibility of deep peroneal nerve neurotisation by the superficial peroneal nerve: an anatomical approach.

Neurotisation involves transfer of nerves for the restoration of function following injury. A number of nerves have been used in different part of the peripheral nervous system. This study was undertaken to develop a practical and relatively safe surgical approach to the treatment of L4 root lesion's. We examined the effectiveness and safety of neurotisation of the deep peroneal nerve and its branches by the superficial peroneal nerve. Twelve legs of dissected cadavers provided for teaching purposes in the anatomy laboratory were used to display the common peroneal nerve and its branches. Each branch was measured using calipers and analysed to investigate the possibility of neurotisation of the deep peroneal nerve by the superficial peroneal nerve and its branches. It was found that of the measured branches, transposition was possible between those to peroneus longus and tibialis anterior on the basis of their diameter and length. In recent decades, advances in microsurgical reconstruction and understanding of the microanatomy have played major roles in improving the results of surgical treatment of nerve injuries. There is a need for further experimental studies on the feasibility of this surgical approach.

Dissection↗
PubMed1999

Morphometric analyses of the development of dermis in human fetuses.

In this study, the morphometric differences of the different dermis regions during the development of the human fetus were investigated. The different dermis regions, namely, cranial, femoral and plantar (sole) parts of 40 fetuses which were between 12th-23.5th week gestation age were obtained from maternity hospital and after the routine H&E histological procedure, the measurement was performed with ocular micrometer. The first sharp increase was observed in the dermis of cranial region. It has been suggested that the thickness of the dermis is dependent on the collagen and elastic fibres, but the flexibility of the dermis is dependent on the number and the structure of the elastic fibres. The early beginning of the increase of the dermis thickness in the cranial part may be due to the effect of the cranio-caudal stimulation on the production of the collagen and elastic fibres in the embryonic term.

Dermis↗
PubMed1992

Post-mortem changes in the normal rat carotid body: possible implications for human histopathology.

The carotid bodies in experimental animals contain only one variety of type I cells whilst in the human organ three varieties of this cell type have been described. We have examined the effects of post-mortem change on the structure of the type I cell of the rat carotid body. When the organ is examined immediately after death of the animal all of the type I cells exhibit similar morphology. With increasing delay in fixation of the tissue the type I cells undergo autolytic changes. Within 2 h of death the nuclei become hyperchromatic and the cytoplasm exhibits an increasing eosinophilia. In carotid bodies fixed 4 h post-mortem a further type I cell variant is seen in which the nucleus lacks a chromatin pattern and become pyknotic. We believe that previous descriptions of three varieties of type I cells in the human carotid body are based upon a description of post-mortem change. Furthermore, in any study of this highly oxygen dependent tissue it is essential that due account be taken of the delay between death and fixation.

Animals↗