Mehmet Selçuki

Patients with urinary incontinence often benefit from surgical detethering of tight filum terminale

Abstract We retrospectively reviewed 77 patients with a tethered spinal cord syndrome to evaluate the results of neurosurgical treatment. The patients were divided into two groups: in group 1 there were 17 patients with primary tethered cord who had normal level conus medullaris (NLCM) and normal thickness filum terminale (NTFT) with urinary incontinence, and group 2 was made up of 60 patients with secondary spinal cord tethering after a previous closure of a midline fusion defect who had a low-lying conus medullaris. Neurological examination, radiography, urodynamic tests and electrophysiological findings confirmed the diagnosis. Conventionally, tethered cord syndrome has been defined as a state in which the conus medullaris is located below the L1–2 disc space. However, in a patient with urinary incontinence and a hyperreflexive type of neurogenic bladder, in whom the conus medullaris is found to be at the normal level, there may still be cord tethering that is causing the incontinence. In this study the comparison was based on evaluation of the response to treatment and general characteristics of the syndrome in both groups of patients to draw attention to the general approach to this incapacitating maldevelopment.

The curly tail mouse model of human neural tube defects demonstrates normal spinal cord differentiation at the level of the meningomyelocele: implications for fetal surgery.

Abstract The paralysis associated with lumbosacral meningomyelocele has been attributed both to myelodysplasia and to degeneration of the exposed neural tissue. Surgically created dysraphism shows that exposure of an intact spinal cord in a genetically normal animal results in degeneration of the normal nervous tissue and subsequent paralysis. Our objective was to study neuronal differentiation in the curly tail mouse mutant model, which develops lumbosacral meningomyelocele naturally and is a phenocopy of nonsyndromic human neural tube defects. Prenatal repair of meningomyelocele assumes that the normal neuronal differentiation program occurs despite failure of neurulation. Here we demonstrate that this most suitable animal model has normal differentiation of neuronal structures at the level of the meningomyelocele. TuJ1, an antibody to neuronal specific class III β-tubulin, an early marker of neuronal differentiation, was used to stain paraffin-embedded sections of curly tail mouse embryo meningomyelocele. Embryos were examined at embryonic day 13.5 (E13.5). The inbred mouse strain, C57BL6/J, which is genetically similar to the curly tail mouse, was used as a control in these studies. We show that early neuronal differentiation appears intact within the meningomyelocele. TuJ1 stains structures within the open neural tube. Motor neurons are present in the ventral horn and ventral roots. Dorsal root ganglia are present and of similar size to controls. The staining pattern is similar to that seen in the C57BL/6J control mouse, although dorsal structures are laterally displaced in the curly tail meningomyelocele. Based on this model, fetal surgery to repair human meningomyelocele may preserve neurological function in those cases where there is not an inherent genetic defect of the neural tissue.

The effects of meloxicam on neural tube development in the early stage of chick embryos.

AIM The aim of this study is to demonstrate the effect of meloxicam in early stage chick embryos on neural tube development. MATERIAL AND METHODS One hundred specific pathogen-free (SPF) chicken eggs were used to investigate the neurulation. SPF eggs were invastigated in four groups (n:25). All of the groups were incubated at 37.2 +/- 0.1 degrees C and 60 +/- 5 % relative humidity for 30 hours, and an embryological development in the ninth stage as classified by Hamburger and Hamilton was obtained. In the end of the 30th hour, group A(control group) was administered 0.1 ml of saline (0.9% NaCl) in ovo and the other groups were administered meloxicam in increasing doses. At the end of 72 hours, all of the embryos were extracted from eggs and they underwent pathological examination with hematoxylin eosine and immunohistopathological examinations with CD138 and tubulin beta II. RESULTS While the groups Aand B showed no neural tube defects, totally eight defective embryos were detected in the groups C and D (three in group C and five in group D. CONCLUSION Our results suggested that meloxicam, a nonselective COX inhibitor, caused neural tube closure defects when injected at supratherapeutic doses. However, further studies with larger numbers of subjects are needed for its use in lower doses.

Neural tissue continues its maturation at the site of neural tube closure defects: implications for prenatal intervention in human samples

ObjectiveOur objective was to investigate the relation between the embryological development and neural tissue maturation at the site where the neural plate failed to form a neural tube.Material and methodsSamples from 15 aborted human fetuses with neural tube defects (NTD). All of the fetuses were between 20 and 25 gestational weeks old. Indicators of neural tissue maturation, formation of basal lamina, expression of integrins and neuron specific class III beta tubulin (tuj1) were investigated. To detect the adverse effects of the environment, if any, p53 and bcl-2 activity at both sites of the open and closed neural plate were investigated as well.ResultsNo difference was found in the expression of maturation-related molecules at the site of the neural plate that remained open compared with the site where the neural tube is normally formed. While high p53 activity was noted in neural tissue at the site of the neural tube defect, no such activity was detected in the neural tissue where the neural tube is normally formed.ConclusionOur results suggested that maturation and differentiation of neural tissue continued regardless of the failure of neural tube closure. Therefore, the neurological deficits that are encountered in NTD patients should be related to secondary damage such as amnion fluid toxicity, uterus contractions, labor, etc. It seems valuable to save the neural plate before the negative effects of the environment renders the neural tissue functionless.

Intracranial hydatid cyst is a rare cause of midbrain herniation: A case report and literature review

Hydatid disease is a parasitic infection affecting the brain in about 2% of the cases. Brain involvement is most commonly observed in children. Here, we report a 13-year-old male patient who presented with headache, nausea, and vomiting. Before cranial computed tomography (CT) was performed, the patient had generalized epileptic seizures. He was disoriented, and had anisocoria with dilatation of the right pupilla. CT showed a cystic lesion of 10-cm diameter in the right temporoparietal region that had caused a shift of the midline structures to the contralateral side; an urgent operation was performed as there were signs of midbrain herniation.

Neurotoxic effects of local anesthetics on the mouse neuroblastoma NB2a cell line

Abstract Local anesthetics are used clinically for peripheral nerve blocks, epidural anesthesia, spinal anesthesia and pain management; large concentrations, continuous application and long exposure time can cause neurotoxicity. The mechanism of neurotoxicity caused by local anesthetics is unclear. Neurite outgrowth and apoptosis can be used to evaluate neurotoxic effects. Mouse neuroblastoma cells were induced to differentiate and generate neurites in the presence of local anesthetics. The culture medium was removed and replaced with serum-free medium plus 20 μl combinations of epidermal growth factor and fibroblast growth factor containing tetracaine, prilocaine, lidocaine or procaine at concentrations of 1, 10, 25, or 100 μl prior to neurite measurement. Cell viability, iNOS, eNOS and apoptosis were evaluated. Local anesthetics produced toxic effects by neurite inhibition at low concentrations and by apoptosis at high concentrations. There was an inverse relation between local anesthetic concentrations and cell viability. Comparison of different local anesthetics showed toxicity, as assessed by cell viability and apoptotic potency, in the following order: tetracaine > prilocaine > lidocaine > procaine. Procaine was the least neurotoxic local anesthetic and because it is short-acting, may be preferred for pain prevention during short procedures.

Congenital dermal sinus tract of the spine: experience of 16 patients.

Congenital dermal sinus tract is a rare entity which lined by epithelial cells and can end anywhere between subcutaneous planes to thecal sac. These tracts may be accompanied with other pathologies such as lipomyelomeningocele, myelomeningocele, split cord malformation, tethered cord, filum abnormality and inclusion tumors and treatment includes resection of tract with intradural exploration. The authors review their experience with 16 cases. Clinical, radiological appearance and treatment of these lesions discussed with literature review.

Missing Screw as a Rare Complication of Anterior Cervical Instrumentation

Although anterior cervical arthrodesis is an effective procedure for the treatment of cervical disorders, the method has some complications. Here, we describe this rare complication of cervical instrumentation with a literature review. A 23-year-old male patient was operated for a C6-C7 dislocation. At postoperative month 10, he presented with hemoptysis and dysphagia. Cervical roentgenograms showed anterior migrations of one broken screw and a plate-locking screw at the C6 corpus. One screw was missing. We concluded that the missing screw had perforated the esophagus and had been eliminated spontaneously through the gastrointestinal tract. No screw should migrate. Even loose screws should be noted in follow-up X-ray studies. If such findings are detected, a second operation for revision should be considered as soon as possible to prevent potentially fatal complications.

Tethered Cord Syndrome in Adults: Experience of 56 Patients.

AIM The aim of this study was to describe the results of surgery performed in a group of adult patients with tethered cord syndrome with their outcomes. MATERIAL AND METHODS This retrospective study included 56 patients. There were 38 females and 18 males. All patients were older than 18 years. RESULTS The mean age at referral was 36 years and 1 month. The mean follow-up period was 10 months 27 days. 95% of all patients with back and leg pains improved and 5% remained the same. Three patients with motor deficits remained the same in the postoperative period. Of the 16 patients with urological complaints, 10 improved, 5 unchanged and 1 patient died in the postoperative first day due to pulmonary embolism. CONCLUSION The syndrome of tethered cord may be a situation to be treated even in the elderly in case of normal level conus medullaris and filum terminale with a normal appearance as well as a low-lying conus and thick filum. To prevent overlooking the diagnosis of tethered cord and/or unnecessary spinal surgeries, the tethered cord syndrome should be remembered in the differential diagnosis list in the presence of back and leg pains, neurological deficits or urological complaints.

Cutting filum terminale is very important in split cord malformation cases to achieve total release.

AimSplit cord malformations (SCMs) are rare congenital anomalies of the vertebrae and the spinal cord. Tethered cord syndrome (TCS) is a clinical condition of various origins that arises from tension on the spinal cord. Radiographic findings may include and/or associate split cord malformations and the other neural tube defects. However, the spinal cord can even be tethered by a filum terminale with normal appearance and normal level conus medullaris in magnetic resonance imaging (MRI). The aim of our study is to show whether SMC patients with normal or abnormal MRI findings had all histological abnormal filum terminale and also to show that the standard SCM repairing operation without cutting filum will not achieve total release.Material and methodsWe have reviewed 33 SCM patients between July 2005 and December 2013. They were operated by adding untethering procedure of filum terminale following standard surgical intervention, and a part of the filum was taken for histopathological examination even though MRI did not show the presence of abnormality of filum terminale.ResultsWe found that abnormal filum terminale with a normal appearance may had dense collagen fibers, wide and numerous capillaries, and hyaline formation, while normal filum terminale is a mixture of collagen fibers and blood vessels. We did not obtain positive Verhoeff elastic fiber staining. The elastic fibers had disappeared in all fila terminalia, except control cadaver group.ConclusionOur results showed that all fila of SCM patients had loss of elastic fibers and increased of hyalinization, which means loss of elasticity of filum terminale. Less severe traction may remain asymptomatic in childhood and present with neurological dysfunction later in life. For this reason, surgical procedure of SCM patients including releasing of filum terminale seems more beneficial for the patients and be better for long term.