Fatih Serhat Erol

Irrigation vs. closed drainage in the treatment of chronic subdural hematoma.

A number of different techniques are used to treat chronic subdural hematomas surgically. In this study, 70 chronic subdural hematomas were surgically treated and analyzed prospectively. Patients were classified according to clinical features and computed tomography images. Results of the cases that underwent burr-hole craniostomy-irrigation (group A; n=35) were compared with those undergoing burr-hole craniostomy-closed system drainage (group B; n=35). The most common etiological factor was trauma in both groups. Complete resolution in the early period was higher in group B compared to group A (60% vs. 40%). However, no difference was noted at the first month-follow-up. Recurrence rates were 17% in group A and 14% in group B. No significant difference was noted in terms of hospitalization duration or postoperative complications. In conclusion, we believe that the burr-hole craniostomy-irrigation technique is a reliable and effective method compared to burr-hole craniostomy-closed system drainage in the treatment of chronic subdural hematoma.

Review of complications due to foramen ovale puncture

We aim to evaluate the mechanisms responsible for complications during trigeminal rhizotomy via foramen ovale puncture. Ten dry skulls and 10 skull-base specimens were investigated in the present study. In cadaveric skull-base specimens, the anatomical relationships between the foramen ovale, mandibular nerve and Gasserian ganglion and the surrounding neurovascular structures were investigated intradurally. The distance between the foramen ovale and Gasserian ganglion was measured as 6 mm. The abducent nerve, adjacent to the anterior tail of the petrolingual ligament, was observed passing along the lateral wall of the cavernous sinus. Advancement of the catheter more than 10 mm from the foramen ovale is likely to damage the internal carotid artery and the abducent nerve at the medial side of the petrolingual ligament. Thermocoagulation of the lateral wall of the cavernous sinus may damage the cranial nerves by heat, giving rise to pareses.

Microanatomical architecture of dorello's canal and its clinical implications

OBJECTIVE We investigated the membranous architecture of the abducens nerve at the petroclival region and describe the characteristics of this area in cadaveric specimen and two children with hydrocephalus and sixth nerve palsy using magnetic resonance imaging (MRI). MATERIALS AND METHODS Five adult cadaver heads were used to investigate the petroclival part of the abducens nerve. The heads were injected with colored latex for microsurgical dissection, and the length of the dural sleeve of the abducens nerve and its width at the apex were measured. In one cadaver head, the area between the petroclival entrance porus of the abducens nerve and the cavernous sinus was histologically studied under light microscopy. In two patients with hydrocephalus and abducens nerve palsy, the petroclival area was screened by using the MRI fat suppression technique. RESULTS In the cadavers, the arachnoid membrane on the clivus extended within the dural sleeve as far as the petrous apex, as an extension of the subarachnoid space. The average length of the dural sleeve was 9.5 mm and the average width was 1.5 mm at the apex, where the nerve entered the cavernous sinus. MRI scans showed that the cerebrospinal fluid distance of the petroclival region was 5 mm in the first patient and 7 mm in the second. CONCLUSION The subarachnoid space inside the dural sleeve of the abducens nerve can be defined by using thin-slice MRI scans. Enlargement of the dural sleeve at the petroclival region may coexist with the abducens nerve palsy. It has been documented in this study that the arachnoid membrane forms a membraneous barrier between the subarachnoid and subdural spaces within Dorellos canal.

Comparison of the effects of octreotide and melatonin in preventing nerve injury in rats with experimental spinal cord injury.

In this study, we aimed to investigate the biochemical and histopathological protective effects of octreotide and melatonin in an experimental model of spinal cord injury. Fifty- six male albino Wistar rats were divided into four groups. Rats in the G1 group (n=7; control group) did not undergo any treatment except for anesthesia prior to being killed. Rats in the G2 group (n=7) underwent laminectomy and aneurysmal clip application at the T4-5 level. G3 group rats (n=14) were either treated with a 7.5 mg/kg intraperitoneal dose of melatonin (Sigma, St. Louis, MO, USA) immediately after laminectomy, then the same dose again on the day following injury (G3a), or given three equal doses over 10 days to achieve a total dose of 7.5 mg/kg/day (G3b). G4 group rats (n=14) were either treated with a 30microg/kg intraperitoneal dose of octreotide (Sandostatin; Novartis, Istanbul, Turkey) immediately after laminectomy, then the same dose again on the day following injury (G4a), or given three equal doses over 10 days to achieve a total dose of 30miocrog/kg/day (G4b). Rats in the G3 and G4 groups were sacrificed on days 1 and 10 after spinal cord injury (n=7 at each time point) and spinal cord samples were obtained. Tissue malonyldialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) levels were assayed. G3a, G3b and G4b had significantly lower levels of MDA than G2 (p<0.01). G3b had significantly higher SOD and GSH-Px levels than G2 (p<0.01). Histopathologically, melatonin significantly reduced necrosis and degeneration in both the initial and late stages (p<0.01). Octreotide had significant effects on necrosis and degeneration during the late stages, and on edema and congestion in both the initial and the late stages of injury (p<0.01). Melatonin was found to be superior to octreotide with respect to the prevention of congestion, edema, axonal degeneration and necrosis.

Giant aneurysm of the azygos pericallosal artery: case report and review of the literature.

BACKGROUND Pericallosal aneurysms are encountered less than 6.7%, and giant aneurysms among them even less. Giant azygos pericallosal artery aneurysm at the callosomarginal bifurcation is extremely rare, and our case presented herein is the second one. The case is discussed with thorough review of the literature. METHODS A 65-year-old woman presented with an extremely rare giant aneurysm on the azygos pericallosal artery manifesting as subarachnoid hemorrhage in World Federation of Neurosurgical Societies Grade 3. Computed tomography (CT), magnetic resonance angiography (MRA), and four vessel angiography revealed a giant azygos pericallosal artery aneurysm associated with a second aneurysm at the left M1. RESULTS After recovery to Grade 2, she underwent surgery via the right frontal interhemispheric approach for the azygos artery aneurysm on the 17th day after bleeding. The true dimensions of the aneurysm were greater than indicated by angiography because of partial thrombosis. Trilobulate aneurysm was carefully dissected from the surrounding structures. Postoperative cerebral angiography showed no filling of the clipped aneurysm and preservation of circulation. CONCLUSIONS The treatment of distal anterior cerebral artery aneurysms is often difficult, because of their broad-based irregular configurations and adherence to surrounding tissue, tendency to bleed irrespective of size and the coexistence of other cerebral aneurysms. However, excellent outcomes can be obtained based on thorough preoperative radiologic evaluation, including magnetic resonance imaging (MRI), and correct selection of surgical approach.

Delayed Trigeminocardiac Reflex Induced by an Intraorbital Foreign Body

Objective: To emphasize the importance of the mechanism and surgical approach to trigeminocardiac reflex (TCR) developing 48 h after orbital trauma due to a foreign body. Case Report: After gunshot injury of a 17-year-old male patient, computerized tomography evaluation revealed a right globe perforation and an intraorbital metallic foreign body in the right orbita adjacent to the lateral wall. The ocular perforation was repaired, but the foreign body was not removed. Constant bradycardia (45/min) developed 48 h after the operation. Since there were no cardiological findings, a temporary cardiac pacemaker was inserted and on the 6th postoperative day, the foreign body was removed through orbitolateral approach. After the removal of the foreign body, bradycardia completely recovered. Conclusion: In the presence of an intraorbital foreign body accompanied by globe perforation, TCR may develop 48 h after the trauma and insertion of a temporary pacemaker may be required to control the cardiac rhythm. In this paper, the delayed TCR complication presented an indication for the removal of the intraorbital foreign body.

Neuroprotective effect of regional carnitine on spinal cord ischemia—reperfusion injury

OBJECTIVE The purpose of this study was to investigate the effect of regional infusion of carnitine on spinal cord ischemia--reperfusion (I--R) in rabbits. METHODS The 36 rabbits were divided into four equal groups, group I (sham operated, no I--R injury), group II (control, only I--R), group III (I--R+intraaortic lactated Ringers, LR, during aortic occlusion), group IV (I--R+LR plus 100mg/kg carnitine). Spinal cord ischemia was induced by clamping the aorta both below the left renal artery and above the aortic bifurcation. The spinal cord function of all animals was assessed clinically 24h after aortic declamping. Spinal cord samples were taken to measure the levels of tissue malondialdehyde (MDA) and to evaluate the histopathological changes. RESULTS We found significant increases in the levels of MDA in groups II and III compared with group I (P<0.01), and elevation of MDA in group IV was insignificant. In group II, all animals (100%) were paraplegic with Tarlovs score of 0 and in group III, eight animals (88%) were paraplegic with Tarlovs score of 0 or 1. None of the animals (0%) from group IV was paraplegic. Histologic examination of spinal cords from group IV animals revealed that the appearance of the spinal cord was relatively preserved, whereas spinal cords from groups II and III had evidence of acute neuronal injury. CONCLUSION The results suggest that regional infusion of carnitine during aortic clamping reduces spinal cord injury and prevents neurologic damage in rabbit spinal cord I--R model.

Medroxyprogesterone acetate, enoxaparin and pentoxyfylline cause alterations in lipid peroxidation, paraoxonase (PON1) activities and homocysteine levels in the acute oxidative stress in an experimental model of spinal cord injury.

Summary. Background: Effects of medroxyprogesterone acetate, enoxaparin and pentoxyfylline on lipid peroxidation, antioxidant defence system, paraoxonase activities, and homocysteine levels in an experimental model of spinal cord injury were investigated. Method: Sixty-three male albino Wistar rats were anaesthetized by 400 mg/kg chloral hydrate and divided into 5 groups. G1 (n 7) = control group provided the baseline levels. G2–G5 underwent T3–6 total laminectomies and spinal cord injuries by clip compression at T4–5 levels. Medications were applied to G3–G5 right after the injury. Hence, G2 constituted laminectomy + injury (lam+I); G3 = lam + I + medroxyprogesterone acetate (MPA), G4 = lam + I + enoxaparin (E), and G5 = lam+I+pentoxyfylline (P) groups. Animals were decapitated either at the 1st or 4th hour after injury. Tissue and blood malonyldialdehyde (MDA) and plasma homocysteine and erythrocyte superoxide dismutase (SOD) levels, and erythrocyte glutathione peroxidase (GSH-Px) and plasma paraoxonase (PON1) activities were assayed. SPSS 9.0 program was used for statistical analysis and graphics. Intergroup comparisons were made by Bonferroni corrected Mann Whitney U test (P<0.025), and intragroups comparisons by Wilcoxon Rank test (P<0.03). Findings: In intergroup comparison, G1–G2, G1–G3, G1–G5, G2–G3, G2–G4, and G4–5 groups differed from each other for all parameters (P<0.025, MWU) except for G4–G5 4th hour MDA levels. G1–G4 was similar for all 1st hour parameters (P>0.025, MWU), but different for 4th hour (P<0.025, MWU) except for GSH-Px and SOD levels. For G2–G5, all parameters for 1st and 4th hour were similar except for 4th PON1, Hcy and SOD levels. For G3–G4, all 1st hour parameters were different from each other (P<0.025, MWU); whereas all 4th hour parameters were similar except for SOD level. For G3–G5, all parameters at 1st and 4th hour were similar except for 4th hour GSH-Px, PON1, and Hcy. In intragroup comparison, all parameters differed from each other at all times (P<0.03, WRT) except for 1st hour G4 MDA, Hcy and SOD levels compared to basal levels. Interpretation: In injury groups, plasma Hcy levels decreased and PON1 activities increased as erythrocyte SOD level and GSH-Px activities decreased in parallel to increases of tissue and blood MDA levels. These changes were relatively suppressed by MPA, enoxaparin and pentoxyfylline administrations at varying degrees. Enoxaparin was the most powerful agent, particularly at 1st hour. MPA was also effective, particularly at 4th hour. Pentoxyfylline despite having slight effect at 4th hour, was not effective according to both control and injury groups. Enoxaparin and MPA can be used in the treatment of spinal cord injuries. PON1 and Hcy are helpful in monitoring the antioxidant defence system as well as SOD and GSH-Px, both in injury and medically treated groups.

Prediction of Minor Head Injured Patients Using Logistic Regression and MLP Neural Network

In this study it is aimed to assess the posttraumatic cerebral hemodynamia in minor head injured patients. Eighty patients with minor head injury (Group 1) evaluated in the early 8 h of posttraumatic period between July 2003 and February 2004. The control group (Group 2) has composed of 32 healthy people. Bilateral blood flow velocities of middle cerebral arteries (MCA) had measured using transtemporal technique while internal carotid arteries were evaluated by submandibular examination. Two different mathematical models such as the traditional statistical method on the basis of logistic regression and a multi-layer perceptron (MLP) neural network are used to classify the age, sex, velocitiy parameters of MCA, mean velocity of extracranial ICAs and VMCA/ VICA ratios. The neural network was trained, cross-validated and tested with subject’s transcranial Doppler signals. As a result of these classifications, we found the success rate of logistic regression, the success rate of MLP neural network is 88.2 and 89.1%, respectively. The classification results show that MLP neural network is offering the best results in the case of diagnosis.

The significance of the percentage of the defect size in spina bifida cystica in determination of the surgical technique.

Abstract Aim. Our aim was to classify meningoceles and meningomyeloceles in terms of defect area as a percentage of the thoracolumbar region to make it possible to select the surgical technique accordingly. Materials and methods. Thirty-two cases were included in the study program. Any defect smaller than 8% of the thoracolumbar region was primarily sutured and classed as grade 1. Results. The defects that it was not possible to handle with primary suture because of the broad base and thereby closed with muscle–skin flaps were those occupying more than 8% of the thoracolumbar region and these were classed as grade 2. It was not possible to perform primary repair of any defect occupying more than 8% of the thoracolumbar area. Conclusion. The use of combined latissimus dorsi+gluteus maximus muscle–skin flaps was found to be safe in broad-based meningomyelocele defects, as they provide wider closures and permanent bolstering of the meningomyelocele defect, thus protecting the region against multiple trauma.