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Öğe An anatomic study for a modified technique for bypass of the external carotid artery to the proximal middle cerebral artery(SPRINGER, 2008) Cengiz, Sahika Liva; Ozturk, Kayhan; Cicekcibasi, Aynur Emine; Salbacak, Ahmet; Ustun, Mehmet ErkanWe aimed to evaluate whether bypass of the external carotid artery (ECA) to the middle cerebral artery (MCA) can be established by a short saphenous vein graft in order to increase the anastomosis patency. The method was performed to ten adult cadaver sides. We described a modified technique for bypass of the ECA to the M2 segment of MCA. The diameters of the vessels and graft length were measured by using an electronic micrometer. The mean diameter of the superior, middle, and inferior trunks of the MCA with trifurcation were 1.7 +/- 0.15, 2.2 +/- 0.25, and 2.0 +/- 0.2 mm, respectively, whereas the mean diameter of the superior and inferior trunks of the MCA with bifurcation were 2.1 +/- 0.2 and 2.3 +/- 0.3 mm, respectively. The mean diameter of the ECA was 3.75 +/- 0.4 mm. The mean length of the saphenous vein graft was 71.5 +/- 3.9 mm. The high-flow ECA to proximal MCA bypass using a short venous graft can supply enough blood flow to establish cerebral revascularization with a straighter route.Öğe Cerebral Abscesses in Behcet's Disease: A Case Report(TURKISH NEUROSURGICAL SOC, 2012) Tokgoz, Serhat; Ogmegul, Aysegul; Mutluer, Muzaffer; Kivrak, Ali Sami; Ustun, Mehmet ErkanBehcet's disease is a multisystem relapsing inflammatory disorder of unknown cause. Neurological involvement is one of the most serious causes of long-term morbidity and mortality in Behcet's disease. Cerebral abscess is very rare in literature. A 45-yr-old man with Behcet's disease manifesting focal epileptic seizure and multiple cerebral abscesses is reported in the case. He was diagnosed with cerebral abscess and was treated with antibiotics but no improvement occurred. Excisional biopsy was performed and the lesions were consistent with abscess. The clinical state of the patient gradually improved. The patient had no further complications. The etiology, and clinical and magnetic resonance imaging findings are discussed.Öğe A Comparison of the Effects of Adcon-L, Mitomycin C and Sodium Hyaluronate in Experimental Epidural Fibrosis in Rabbits(JOURNAL NEUROLOGICAL SCIENCES, 2011) Kaya, Bulent; Esen, Haci Hasan; Ustun, Mehmet ErkanObjective: Epidural fibrosis and leptomeningeal adhesion formation are among the common causes of failed back surgery syndrome. Various materials have been used to prevent the compressive effect of postoperative epidural fibrosis on neural structures. The effects of Adcon L, Mitomycin C and sodium hyaluronate on epidural fibrosis compared in this experimental study. Methods: 28 rabbits divided into 4 different groups. L5 total laminectomy performed under ketamine and xyzlazine anasthesia. Group1 settled as control group and had no medications after laminectomy. Adcon L in group 2, Mitomycin C in group3 and sodium hyaluronate in group 4 were applied to laminectomy area. All groups sacrified 6 weeks after laminectomy. Histologic slices were invastigated under light microscobe according to their histopathological features and the groups were compared. Result: Grade 3 fibrosis determinated in group1. Statistically significant differences between group1 and all other groups were obtained (p < 0.05) No statistically significant differences was determinated between group 2, 3 and 4 respectively. Conclusions: All medications we use decreased postoperative epidural fibrosis in this study. But further studies are needed for routine application of these medications.Öğe The efficacy of intrathecal administration of a very low dose potirelin after acute spinal cord injury(ELSEVIER SCI LTD, 2008) Cengiz, Sahika Liva; Ustun, Mehmet Erkan; Topcu, Cemile; Ahmet, A. K.Background and object: The objective of this study was to determine the effect of a very tow dose protirelin in cerebrospinal fluid (CSF) glucose, magnesium and lactate levels after spinal cord trauma (SCT) in rabbits. We also aimed to evaluate whether this very tow dose might induce analeptic effect. Material and methods: Twenty rabbits were divided equally into two groups: group I (n = 10) was the control group, suffered from SCT but received only saline after SCT. Group II (n = 10) (treatment group), received a very low dose of 0.05 mg/kg thyrotropin releasing hormone (TRH), analogue protirelin intrathecally after SCT. The basal CSF glucose, magnesium and lactate levels were recorded in both groups. CSF lactate, glucose and magnesium contents were recorded at the same time (an hour before and after) SCT Serum thyroid stimulating hormone (TSH), freetriiodothyronine (73) and freethyroxine (FT4) were measured in all rabbits before and after SCT. Results: Before spinal cord trauma, there were not any significant differences in glucose, lactate and magnesium Levels between group I and II whereas, after spinal cord trauma in group 11, the significant suppression in elevation of Lactate and glucose depletion (p < 0.05) were observed white no significant suppression was observed in magnesium level (p > 0.05) as compared with group I (Table 3). In respect of serum TSH levels, there were not any significant differences between two groups before and after SCT. Conclusions: This study showed that intrathecal TRH has no analeptic effect on serum TSH, FT3 and FT4 levels but can attenuate the increase of lactate levels following spinal cord trauma. No significant decrease in magnesium level and also suppression of glucose decline in group II, may be related to the neuroprotective effects of TRH. (C) 2008 Published by Elsevier Ltd.Öğe Proximal STA to proximal PCA bypass using a radial artery graft by posterior oblique transzygomatic subtemporal approach(SPRINGER, 2009) Ulku, Cagatay Han; Cicekcibasi, Aynur Emine; Cengiz, Sahika Liva; Ustun, Mehmet Erkan; Buyukmumcu, MustafaThe aim of the present study was to investigate the use of a radial artery graft (RAG) for bypass of the proximal superficial temporal artery (STA) to proximal posterior cerebral artery (PCA) by posterior oblique transzygomatic subtemporal approach as an alternative to the external carotid artery (ECA) to PCA anastomosis. We conducted an anatomical and technical study at a university hospital. Five adult cadaveric specimens were dissected. A preauricular vertical skin incision was used. The trunk of STA was identified. A 30 degrees oblique posterior zygomatic arch osteotomy and microcraniotomy was performed. The dura of the middle cranial fossa was then opened. The temporal lobe was retracted, the interpeduncular and ambient cisterns were opened, and the P2 segment of the PCA was exposed. The proximal side of the RAG was anastomosed with the proximal STA and the distal side was anastomosed with the P2 segment. The mean caliber of the proximal STA was 2.25 +/- 0.35 mm. The mean diameter of the P-2 was 2.2 +/- 0.2 mm. The average length of the RAG was 56 +/- Ce3.2 mm. The mean caliber of the proximal and the distal sides of the graft was 2.5 +/- 0.25 mm and 2.3 +/- Ce0.15 mm, respectively. Because the proximal STA to proximal PCA bypass uses a short RAG and their calibers are over 2 mm, this bypass technique can provide a sufficient blood flow and may be a reasonable alternative over ECA to PCA bypass using long grafts.Öğe The role of intravenous immunoglobulin in the treatment of cerebral vasospasm induced by subarachnoid haemorrhage: An experimental study(TAYLOR & FRANCIS LTD, 2011) Cengiz, Sahika Liva; Erdi, Mehmet Fatih; Avunduk, Mustafa Cihat; Tosun, Murat; Ustun, Mehmet Erkan; Gokce, Recep; Yosunkaya, AlperObjectives: The aim of this study was to determine whether intravenous immunoglobulin (IVIG) prevents cerebral vasospasm in rabbits with induced subarachnoid haemorrhage (SAH). The effect of IVIG on apoptosis in the endothelial cells of the basilar artery was also evaluated. Methods: Eighteen New Zealand white rabbits were allocated randomly into three groups. SAH was induced by injecting autologous blood into the cisterna magna. Group 1, the control group, was subjected to sham surgery (no induction of SAH). Group 2 had SAH alone and Group 3 had SAH plus IVIG. Three days after treatment, the animals were sacrificed. The basilar artery tissues were analysed histologically and the malondialdehyde levels in the brain stem tissues were evaluated biochemically. Results: Differences in the histopathological luminal areas and full wall thicknesses in the SAH plus IVIG group and the SAH group were statically insignificant (p > 0.005). The malondialdehyde level was also found to be lower in the IVIG group than in the SAH group, although this difference was not significant (p > 0.005). Conclusion: Although the IVIG treatment was revealed to have no vasodilator effect on the SAH-induced spastic basilar artery, it was shown to have a beneficial effect on the apoptosis of endothelial cells, probably via anti-inflammatory mechanisms.Öğe Transzygomatic-subtemporal approach for middle meningeal-to-P2 segment of the posterior cerebral artery bypass: An anatomical and technical study(THIEME MEDICAL PUBL INC, 2006) Ustun, Mehmet Erkan; Buyukmumcu, Mustafa; Ulku, Cagatay Han; Guney, Oender; Salbacak, AhmetWe evaluated the use of a bypass between the middle meningeal artery (MMA) and P2 segment of the posterior cerebral artery (PCA) as an alternative to an external carotid artery (ECA-to-PCA) anastomosis. Five adult cadaveric heads (10 sides) were used. After a temporal craniotomy and zygomatic arch osteotomy were performed, the dura of the floor of the middle cranial fossa was separated and elevated. The MMA was dissected away from the dura until the foramen spinosum was reached. Intradurally, the carotid and sylvian cisterns were opened. After the temporal lobe was retracted, the interpeduncular and ambient cisterns were opened and the P2 segment of the PCA was exposed. The MMA trunk was transsected just before the bifurcation of its anterior and posterior branches where it passes inside the dura and over the foramen spinosum. It was anastomosed end to side with the P2 segment of the PCA. The mean caliber of the MMA trunk before its bifurcation was 2.1 +/- 0.25 mm, and the mean caliber of the P2 was 2.2 +/- 0.2 mm. The mean length of the MMA used to perform the bypass was 32 +/- 4.1 mm, and the mean length of the MMA trunk was 39.5 +/- 4.4 mm. This bypass procedure is simpler to perform than an ECA-to-P2 revascularization using long grafts. The caliber and length of the MMA trunk are suitable to provide sufficient blood flow. Furthermore, the course of the bypass is straight.
