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Öğe Acute thrombosis of inferior vena cava in a pregnant woman presenting with sciatica: A case report(SPRINGER, 2005) Gormus, N; Ustun, ME; Paksoy, Y; Ogun, TC; Solak, HA 20-year-old pregnant woman was admitted to our department with symptoms of deep venous thrombosis in the left lower extremity and excessive lumbar pain. Low-molecular-weight heparin was administered. She recovered with this treatement, however, severe lumbar pain continued. A lumbar magnetic resonance imageg showed dilated epidural veins compressing the roots and acute thrombosis of the inferior vena cava extending to renal veins. During the same period she had acute deep venous thrombosis in her right leg. An urgent venous thrombectomy was performed. Sciatica and deep venous thrombosis resolved after the operation. Low-molecular-weight heparin was administered until the end of her pregnancy.Öğe Arterial spasm following perimesencephalic nonaneurysmal subarachnoid hemorrhage in a pediatric patient(ELSEVIER SCIENCE INC, 2005) Sert, A; Aydin, K; Pirgon, O; Emlik, D; Ustun, MEPerimesencephalic nonaneurysmal hemorrhage is a benign form of subarachnoid hemorrhages. This entity is well recognized as a distinct type of subarachnoid hemorrhage in adults. However, perimesencephalic nonaneurysmal subarachnoid hemorrhage in pediatric patients is not well recognized. Angiographic changes such as vasospasm are uncommon in patients, especially in pediatric patients suffering from this type of hemorrhage. This case study reports a 12-year-old male who suffered from perimesencephalic nonaneurysmal subarachnoid hemorrhage. Cerebral carotid angiography performed on the tenth day of the posthemorrhagic period revealed severe vasospasm affecting the basilar artery. The patient, treated symptomatically, was discharged after improvement. One year later, magnetic resonance angiography revealed completely normal features. (c) 2005 by Elsevier Inc. All rights reserved.Öğe Effect of gamma-hydroxybutyric acid on lipid peroxidation and tissue lactate level in experimental head trauma(LIPPINCOTT WILLIAMS & WILKINS, 2004) Yosunkaya, A; Ak, A; Bariskaner, H; Ustun, ME; Tuncer, S; Gurbilek, MBackground. This study was designed to determine the effects of gammahydroxybutyric acid (GHB) on tissue lactate and malondialdehyde (MDA) levels in rabbit brain after experimental head trauma. Methods. Thirty New Zealand rabbits were divided equally into three groups: group S was the sham-operated group, group C, and group GHB received head trauma, where group C was the untreated and group GHB was the treated group. Head trauma was delivered by performing a craniectomy over the right hemisphere and dropping a weight of 10 g from a height of 80 cm. GHB was administered 400 mg/kg intravenously for 10 minutes after the head trauma to group GHB. The nontraumatized side was named "1" and the traumatized side was named "2." One hour after trauma, brain cortices were resected from both sides and the concentrations of lactate and MDA were determined. Results There were significant differences between lactate and MDA levels of group S and all other groups (C-1, C-2, GHB(1), and GHB(2)) except between lactate levels of group S and group GHB(1), the nontramnatized and traumatized sides of groups C and group GHB, group C-2 versus group GHB(2), and group C-1 versus group GHB(1) (p < 0.05). Rectal temperature after the administration of GHB in group GHB was found lower than in groups S and C (p < 0.05). Conclusion. These results demonstrate that head trauma leads to an increase in brain tissue lactate and MDA levels, and GHB effectively suppresses the increase of lactate and MDA.Öğe Effect of gamma-hydroxybutyric acid on tissue Na+,K+-ATPase levels after experimental head trauma(WILEY, 2004) Yosunkaya, A; Ustun, ME; Bariskaner, H; Tavlan, A; Gurbilek, MBackground: A failure of the Na+,K+-ATPase activity (which is essential for ion flux across the cell membranes) occurs in many pathological conditions and may lead to cell dysfunction or even cell death. By altering the concentration of specific opioid peptides, gamma-hydroxybutyric acid (GHB) may change ion flux across cell membranes and produce the 'channel arrest' which we assumed will inhibit the failure of Na+,K+-ATPase activity and therefore lead to energy conservation and cell protection. Therefore we planned this study to see the effects of GHB at two different doses on Na+,K+-ATPase activity in an experimental head trauma model. Methods: Forty New Zealand rabbits were divided equally into four groups: group I was the sham-operated group, group II (untreated group), group III received head trauma and intravenous (i.v.) 500 mg/kg GHB and group IV received head trauma and i.v. 50 mg/kg GHB. Head trauma was delivered by performing a craniectomy over the right hemisphere and dropping a weight of 10 g from a height of 80 cm. The non-traumatized (left) side was named as 'a' and the traumatized (right) side as 'b'. One hour after the trauma in groups II and III and craniotomy in group I, brain cortices were resected from both sides and in group I only from the right side was the tissue Na-K-ATPase activity determined. Results: The mean +/- SD of Na+,K+-ATPase levels of each group are as follows: group I - 5.97 +/- 0.55; group IIa - 3.90 +/- 1.08; group IIb - 3.58 +/- 0.90; group IIIa - 5.53 +/- 0.60; group IIIb - 5.33 +/- 0.88; group IVa - 5.05 +/- 0.72; group IVb - 4.93 +/- 0.67. The Na+,K+-ATPase levels of group IIa, IIb, IVa and IVb were significantly different from group S (P < 0.05). There were also significant differences between group IIa and groups IIIa and IVa; group IIb and groups IIIb and IVb (P < 0.05). Conclusions: We conclude that GHB is effective in suppressing the decrease in Na+,K+-ATPase levels in brain tissue at two different dose schedules after head trauma.Öğe Effects of gamma-hydroxybutyrate on cerebrospinal fluid lactate and glucose levels after spinal cord trauma(ELSEVIER SCI LTD, 2004) Guney, O; Celik, JB; Arazi, M; Ustun, METhis study aims to evaluate the effects of gamma-hydroxybutyrate (GHB) after spinal cord trauma (SCT). Twenty rabbits were divided equally into four groups: group I was the sham-operated group, group 11 suffered from SCT but received no treatment, group III was given a dose of 400 mg/kg of GHB intravenously before SCT and group IV received the same dose after SCT. Cerebrospinal fluid (CSF) samples were obtained 30 min before SCT (T-0), at 60 (T-1) and 120 min (T-2) after SCT. There was a threefold increase in lactate levels from baseline value at T-2 in group 11, while statistically significant elevation of the lactate levels were not observed in groups III and IV. Glucose levels at T, and T2 were significantly lower in groups III and IV compared with the control group. The findings of this study demonstrate that GHB can control the increase of CSF lactate and glucose levels following SCT and that this metabolic effect may be associated with neuroprotective physiological changes. (C) 2004 Elsevier Ltd. All rights reserved.Öğe Effects of magnesium sulfate on Na+,K+-ATPase and intracranial pressure level after cerebral ischemia(JOHN LIBBEY EUROTEXT LTD, 2004) Ustun, ME; Bariskaner, H; Yosunkaya, A; Gurbilek, M; Dogan, NIn the present study, the effects of magnesium sulfate on Na+,K+-ATPase levels and intracranial pressure (ICP) after cerebral ischemia in rabbits were studied. Thirty New Zealand rabbits were divided into three groups. Group I was the control group. In group 2 (untreated group) cerebral ischemia was produced by clamping bilateral common carotid arteries for 60 min but in group 3 magnesium sulfate was administered 100 mg/kg i.v. 10 min after opening the clamps. In group 1, ICP recordings were obtained 5, 60 and 120 min after craniectomy. In groups 2 and 3, ICP recordings were obtained 5 min after craniectomy but before clamping, 60 min after clamping and 60 min after opening the clamps. After taking ICP recordings, brain cortices were resected and Na+,K+-ATPase activity was determined by subtracting the enzyme activity in the presence of ouabain from the total activity in the absence of ouabain method. There was a significant difference between Na+,K+-ATPase levels of ;group 1 and group 2 (P < 0.05). There was no significant difference in Na+,K+-ATPase levels between group 1 and 3 (P > 0.05), also preischemic ICP values were same in all groups (P > 0.05). Preischemic and postischemic ICP values were significantly different between groups 1 and 2 (P < 0.05), also postischemic (120 min) ICP values were significantly different between group 2 and group 3 (P < 0.05). ICP values correlate well with Na+,K+-ATPase level. These results demonstrate that cerebral ischemia leads to a decrease of ATPase level in the brain and magnesium sulfate suppresses the decrease of Na+,K+-ATPase, also magnesium sulfate treatment improves the ICP changes.Öğe Effects of magnesium sulfate on spinal cord tissue lactate and malondialdehyde levels after spinal cord trauma(JOHN LIBBEY EUROTEXT LTD, 2005) Ozdemir, M; Cengiz, SL; Gurbilek, M; Ogun, TC; Ustun, MEObjective. In the present study, the effects of magnesium sulfate (MgSO4) on tissue lactate and malondialdehyde (MDA) levels after spinal cord trauma (SCT) in rabbits were studied. Subjects. Thirty New Zeland rabbits. Interventions. The rabbits were divided equally into three groups: group I was the sham-operated group, group II suffered from SCT but received no treatment, group III was given a dose of 100 mg/kg of magnesium sulfate intravenously at 5(th) minute after SCT. Measurements. The lactate and MDA levels were measured in contused spinal cord tissue at 60 minutes after SCT. There was a significant increase of lactate and MDA levels in group II (p < 0.05) when compared with groups I and III, and a significant increase in the level of MDA in group III compared with group I, and also a significant decrease compared with group II, which was the trauma group without treatment (p < 0.05). Conclusion. The findings of this study showed that magnesium sulfate can attenuate the increase of tissue MDA and supply a normalization of lactate levels following SCT which may be related to the neuroprotective effects of (MgSO4).Öğe A modified technique to bypass the maxillary artery to supraclinoid internal carotid artery by using radial artery graft: an anatomical study(HEADLEY BROTHERS LTD, 2005) Arbag, H; Ustun, ME; Buyukmumcu, M; Cicekcibasi, AE; Ulku, CHObjective: This study aims to examine the use of a radial artery graft for bypass of the maxillary artery (MA) to the supraclinoid internal carotid artery (ICA) in treating ICA occlusions. Study design and setting: This method was carried out on five adult cadaver sides. The MA was reached 1-2 cm inferior to the crista infratemporalis, following a frontotemporal craniotomy and a zygomatic arch osteotomy. Extradurally 2-3 cm lateral to the foramen rotundum, a hole was drilled in the sphenoid bone with a 4 mm tipped drill. A radial artery graft was passed through the hole to the inside of the dura. Before giving the infraorbital artery branch, the MA was dissected from the surrounding tissue and transected. The proximal end of the graft was anastomosed end-to-end with the MA and the distal end of the graft end-to-side with the supraclinoid ICA. Results: The mean calibre of the MA was 2.6 +/- 0.3 mm. The mean calibre of the proximal end of the radial artery graft was 2.5 +/- 0.25 mm and the distal end was 2.35 +/- 0.2 mm. The mean length of the radial artery graft was 4.0 +/- 0.5cm. Conclusion: This study suggested that the cases with ICA occlusion, which require high blood flow, may be treated as an alternative to current bypass methods requiring long vein grafts.Öğe Possibility of middle meningeal artery-to-petrous internal carotid artery bypass: An anatomic study(THIEME MEDICAL PUBL INC, 2004) Ustun, ME; Buyukmumcu, M; Seker, M; Karabulut, AK; Uysal, II; Ziylan, TThe possibility of creating a middle meningeal. artery (MMA)-to-petrous internal carotid artery (ICA) bypass was investigated in si cadavers (bilaterally). Such a procedure could be used to treat patients with high cervical vascular lesions and those with tumors of the infratemporal fossa invading the high cervical ICA. After a frontotemporal craniotomy, the foramen spinosum and foramen ovale were exposed extradurally. Immediately posterior to the foramen ovale and medial to the foramen spinosum, the petrous portion of the ICA was exposed with a diamond-tipped drill. The MMA was lifted from its groove, and a sufficient length was transected to perform a bypass with the petrous ICA medially. The mean width of the MMA at the site of anastomosis was 2.3 +/- 0.35 mm. The mean length of MMA from the foramen spinosum to the site of the anastomosis was 9.6 +/- 1.7 mm. Based on these measurements, width and length of MMA appear to be sufficient for a bypass with petrous ICA.Öğe Proximal superficial temporal artery to proximal middle cerebral artery bypass using a radial artery graft: an anatomic approach(SPRINGER, 2004) Buyukmumcu, M; Guney, O; Ustun, ME; Uysal, IK; Seker, MWe present the use of radial artery graft for bypass of the proximal superficial temporal artery to the proximal middle cerebral artery. Six adult cadaver sites were used bilaterally. After apterional incision, 2x2-cm minicraniectomy was performed which began 2 cm behind the zygomatic process of the frontal bone. The superficial temporal artery was transsected before exposing the zygomatico-orbital artery branch. The proximal side of the radial artery graft was anastomosed end-to-end to the proximal superficial temporal artery and the distal side end-to-side to the proximal middle cerebral artery. The mean calibers of the proximal superficial temporal artery and largest trunk of the middle cerebral artery were 2.25+/-0.35 mm and 2.3+/-0.3 mm, respectively. The average graft length was 85+/-5.5 mm. We conclude that such bypasses are simpler than proximal middle cerebral artery revascularization using long vein grafts. This method proves that the caliber of the proximal superficial temporal artery is more suited to providing sufficient flow than the distal superficial temporal artery, and the graft is short. Such bypasses to the middle cerebral artery may be an alternative to those from the distal superficial temporal artery or extracranial carotid artery.Öğe Radial artery graft for bypass of the maxillary to proximal posterior cerebral artery: An anatomical and technical study(TAYLOR & FRANCIS AS, 2004) Ulku, CH; Ustun, ME; Buyukmumcu, M; Cicekcibasi, AE; Ziylan, TObjective-To examine the use of a radial artery graft for bypass of the maxillary artery (MA) to proximal posterior cerebral artery (PCA) as an alternative to the external carotid artery (ECA) to PCA anastomosis used in posterior circulation bypass surgery. Materials and Methods-The method was applied to five adult cadaver sides bilaterally. The MA was easily found 1-2 cm beneath the infratemporal crest after a frontotemporal craniotomy and a zygomatic arch osteotomy. Extradurally, 2-3 cm posterolateral to the foramen rotundum, a hole was drilled in the sphenoid bone with a 4-mm tipped drill. After sylvian fissure, the interpedincular and ambient cisternae were opened and the P2 segment of the PCA appeared. The graft was passed through the hole and dura to reach the P2 segment. Proximal to the infraorbital artery branch, the MA was freed from the surrounding tissue and transected. The proximal side of the radial artery graft was anastomosed end-to-end with the MA and the distal side was anastomosed end-to-side with the P2 segment of the PCA. Results-The average diameter of the MA proximal to the infraorbital artery branch was 2.6+/-0.3 mm. The average diameter of the P2 was 2.2+/-0.2 mm. The average length of the graft was 47+/-5.2 mm. Conclusion-As MA to proximal PCA bypass uses a short radial graft and as the calibers of the MA and PCA are >2 mm such a bypass may provide sufficient blood flow and represents a reasonable alternative to "ECA to PCA'' bypass.Öğe The role of hyperbaric oxygen in the management of subarachnoid hemorrhage(SPRINGER, 2004) Kocaogullar, Y; Ustun, ME; Avci, E; Karabacakoglu, A; Fossett, DObjective: To determine the role of hyperoxic and hyperbaric therapy following experimental subarachnoid hemorrhage (SAH). Design: Prospective, randomized, controlled animal study. Subjects: Thirty male Wistar rats. Interventions: Thirty rats were assessed for an initial neurologic status as double-blinded by two different neurosurgeons using a neurologic severity score (NSS) and then underwent an initial angiographic examination. Two days later, 0.3 ml of homologous blood was injected into the cisterna magna to produce a SAH-induced cerebral vasospasm. The NSS and angiographic examination were then repeated. The rats having no spasm or a spasm under 50% (n=8) and 50% or over 50% (n=22) were grouped separately, as groups 1 and 2, respectively. The rats having 50% or more spasm were further divided randomly into group 2A and 2B. The rats in groups 1 and 2A (n= 11) underwent a 60-min course of 100% oxygen at the atmospheric pressure 1 atmosphere absolute (ata), and group 2B (n= 11) received 100% oxygen at 3 ata for I h. Neurologic assessment was repeated on the next day and 7 days later. Measurements and main results: The animals having no spasm or less than 50% spasm had a better NSS and outcome when compared with the animals having 50% or more spasm. But the animals with 50% or more spasm which underwent hyperbaric therapy were shown to have a better outcome compared to the animals having hyperoxic therapy. Conclusion: Exposure to hyperbaric oxygen therapy seemed to accelerate the recovery of neurologic deficits secondary to experimental SAH.Öğe Saphenous vein graft for bypass of the external carotid artery to supraclinoid internal carotid artery using a modified technique: An anatomical and technical study(TAYLOR & FRANCIS AS, 2004) Ulku, CH; Ustun, ME; Buyukmumcu, M; Cicekcibasi, AE; Uyar, YObjective - To investigate the use of a saphenous vein graft for bypass of the external carotid artery (ECA) to supraclinoid internal carotid artery (ICA) when the proximal middle cerebral artery (MCA) is not suitable for a bypass procedure. Material and Methods - Five adult cadaver sides were used. Dissection required a frontotemporal craniotomy and a zygomatic arch osteotomy, with a hole being opened 2 - 3 mm lateral to the foramen rotundum extradurally. The ECA was found easily via a second incision in the cervical region. The ophthalmic segment of the ICA was exposed by removal of the anterior clinoid process intradurally. After the dura over the hole was opened, the 7 - 8-cm long bypass graft was passed just behind the mandibula and through the hole inside the dura to reach the ICA. The ECA was then transected proximal to the occipital artery (OA) branch and the distal side of the vein graft was anastomosed end-to-end with the ECA and end-to-side with the supraclinoid ICA. Results - The mean diameter of the ECA proximal to the OA was 3.75 +/- 0.4 mm ( range 3.35 - 4.15 mm) and that of the supraclinoid ICA was 3.4 +/- 0.5 mm ( range 2.9 - 3.9 mm). The mean length of the venous graft was 7.5 +/- 0.5 cm ( range 7 - 8 cm). Conclusion - When high blood flow is needed and the proximal MCA is not suitable for a bypass, the bypass described herein may be an alternative to a superficial temporal to MCA bypass as well as to extracranial carotid artery to MCA or ICA bypasses, which both need long vein grafts.Öğe Superficial temporal artery graft for bypass of the maxillary to proximal middle cerebral artery using a transantral approach: an anatomical and technical study(TAYLOR & FRANCIS AS, 2005) Arbag, H; Cicekcibasi, AE; Uysal, II; Ustun, ME; Buyukmumcu, MConclusion. Using a transantral approach, we examined a new bypass of the maxillary artery ( MA) to proximal middle cerebral artery ( MCA). The caliber of the MA was suitable to provide sufficient blood flow. The length of the graft was shorter and it had a straighter course in the new technique than in previously described techniques. Objective. To examine a new bypass of the MA to proximal MCA using a transantral approach as an alternative to other forms of anterior circulation bypass surgery. Material and methods. The method was applied to five adult cadavers bilaterally. The MA and its branches were easily found after removal of the posterior sinus wall using a transantral approach. Then, a hole was created in the sphenoid bone 5 - 6 mm lateral to the posteroinferior edge of the superior orbital fissure extradurally. After the carotid and sylvian cisternae had been opened, the M2 segment of the MCA was exposed. The MA was transected just before the origin of the descending palatine artery branch. After opening the dura over the hole, the MA was passed through the hole to reach the intracranial cavity. The proximal side of the superficial temporal artery graft was anastomosed end- to- end with the MA and the distal side was anastomosed end- to- side with the M2 segment of the MCA. Results. The mean caliber of the MA was 2.4 +/- 0.3 mm before the origin of the descending palatine artery branch. The mean caliber of the largest trunk of the M2 segment of the MCA was 2.3 +/- 0.3 mm. The average length of the graft was 24 +/- 3 mm.
