Unal Ozum

A safe and effective method for treatment of chronic subdural haematoma.

OBJECTIVE Burr-hole irrigation and burr-hole drainage without irrigation are the most popular methods for treatment of chronic subdural haematoma. It is not well known if irrigation is necessary or which method has a higher recurrence rate. We compared the recurrence rates of those two methods. MATERIALS AND METHODS Forty-two patients were treated by burr-hole irrigation (irrigation group), whereas 38 patients were treated by burr-hole drainage (drainage group). Recurrence rate and its relation with sex, age, haematoma localization and aetiology were investigated in both groups. RESULTS There was no significant difference between recurrence rates of the two groups. There was also no correlation between recurrence rate and age, sex, haematoma localization, or aetiology. CONCLUSIONS There was no significant difference between recurrence rates of the two groups. Since the burr-hole drainage method is simpler to carry out, its use may be preferable.

Mutation in MEOX1 gene causes a recessive Klippel-Feil syndrome subtype

BackgroundKlippel-Feil syndrome (KFS) is characterized by the developmental failure of the cervical spine and has two dominantly inherited subtypes. Affected individuals who are the children of a consanguineous marriage are extremely rare in the medical literature, but the gene responsible for this recessive trait subtype of KFS has recently been reported.ResultsWe identified a family with the KFS phenotype in which their parents have a consanguineous marriage. Radiological examinations revealed that they carry fusion defects and numerical abnormalities in the cervical spine, scoliosis, malformations of the cranial base, and Sprengel’s deformity. We applied whole genome linkage and whole-exome sequencing analysis to identify the chromosomal locus and gene mutated in this family. Whole genome linkage analysis revealed a significant linkage to chromosome 17q12-q33 with a LOD score of 4.2. Exome sequencing identified the G > A p.Q84X mutation in the MEOX1 gene, which is segregated based on pedigree status. Homozygous MEOX1 mutations have reportedly caused a similar phenotype in knockout mice.ConclusionsHere, we report a truncating mutation in the MEOX1 gene in a KFS family with an autosomal recessive trait. Together with another recently reported study and the knockout mouse model, our results suggest that mutations in MEOX1 cause a recessive KFS phenotype in humans.

Endothelial Nitric Oxide Synthase Gene [G894T] polymorphism as a possible risk factor in aneurysmal subarachnoid haemorrhage

SummaryBackground. The exact aetiology, growth and rupture of intracranial aneurysms is unclear. In this study we investigated a possible association between intracranial aneurysm rupture and polymorphism of the endothelial nitric oxide synthase gene G894T.Methods. Endothelial nitric oxide synthase gene polymorphism of 53 patients with ruptured intracranial aneurysms and 60 control subjects were analysed by the polymerase chain reaction-restriction fragment length polymorphism technique. The genotype distribution and allele frequencies of endothelial nitric oxide synthase gene polymorphism in patients with ruptured intracranial aneurysm and healthy subjects were compared.Findings. The homozygous (TT) genotype frequency was significantly higher in patients with ruptured intracranial aneurysms. It was also found that the presence of eNOS 894TT genotype was significantly associated with the risk of intracranial aneurysm rupture (p < 0.05).Conclusion. Polymorphism in exon 7 of the endothelial nitric oxide synthase gene G894T seems to be a possible risk factor for intracranial aneurysm rupture.

Biological understanding of the cardiovascular risk associated with major depression and panic disorder is important.

Abstract Introduction. Panic disorder (PD) and major depressive disorders (MDD) are serious mental disorders but the mechanisms underlying the pathophysiology are poorly understood. Nitric oxide (NO) is a gas considered to play an important role in mediating anxiety and stress response and is synthesised from nitric oxide synthase (NOS). The endothelial isoform (eNOS) has been found also in platelets. Homocysteine (Hcy) is an amino acid which naturally occurs in the human body. Elevated levels are linked to increased risk of cardiovascular, neurological and psychiatric diseases. In this study we aimed to evaluate NO, platelet aggregation and Hcy levels in PD and MDD patients. Materials and methods. Nineteen PD and 18 MDD patients participated in this study. NO levels were measured spectrophotometrically, platelet aggregation levels were measured in an aggregometer and Hcy levels were measured by HPLC. Results. NO levels were significantly lower in patients with MDD and PD than in control subjects (P < 0.05). Hcy and platelet aggregation levels were significantly higher in patients with MDD and PD than in control subjects (P < 0.05). Conclusion. Further more detailed studies are needed to find out the effects of drugs on these parameters or to disclose the exact mechanism underlying the alteration of these parameters.

The therapeutic effect of continuous intracisternal L-Arginine infusion on experimental cerebral vasospasm

Summary Background. Recent studies on the pathogenesis of cerebral vasospasm following subarachnoid haemorrhage (SAH) suggest a breakdown of the balance between the vasoconstrictor and vasodilator systems. A shortage of a major cerebral vasodilator, nitric oxide (NO), has been accused of causing this breakdown. We investigated the effect of continuous intracisternal infusion of a NO precursor, L-Arginine, in a rabbit SAH model. Method. Three experimental groups were designated: Group 1 – Cerebral blood flow (CBF) data was obtained via transorbital Doppler ultrasonography (TDU) in 8 normal rabbits. Group 2 – Intracisternal catheter placement and TDU study during saline infusion were performed in 8 animals at the 4th day of SAH, Group 3 – SAH occurred in 8 animals. 4 days later, L-Arginine was infused intracisternally for 1 hour, while TDU was performed before and during infusion. CBF parameters which were obtained via TDU measurement or calculations, were compared. Findings. The results of TDU revealed significant vasospasm in all SAH animals, as well as resolution of vasospasm with L-Arginine infusion. After 20 minutes of infusion, a steady and sustained vasodilation was obtained in the third group. The analysis of CBF data revealed a significant difference in SAH values, and no difference in control animals. Interpretation. Our results support the contribution of the “NO shortage” concept in the pathogenesis of cerebral vasospasm and overconsumption of L-Arginine during the post-SAH period may cause this shortage. L-Arginine treatment may be useful for the prophylaxis and treatment of cerebral vasospasm. The intracisternal infusion method can eliminate the short action time disadvantage of L-Arginine.

Orbital lymphangioma and its association with intracranial venous angioma.

Orbital lymphangioma is an uncommon, benign cystic lesion, generally manifest in childhood. It usually presents with a slowly progressive proptosis, displacement of the globe, ptosis and restriction of eye movements. Occasionally, focal lesions may remain asymptomatic. Spontaneous intraorbital haemorrhage may cause acute proptosis, compressive optic neuropathy and loss of vision. An 8-year-old girl presented with progressive left proptosis and a unilateral soft tissue mass at the supraorbital frontal region. Multiple intracranial venous angiomas were seen on MRI. Surgical decompression of the optic nerve was performed because of progressive decrease in visual acuity. We review the relevant literature; rarity of the orbital lymphangioma and its association with non-contiguous intracranial vascular anomalies were emphasized.

Primary multiple cerebral hydatid cysts with unusual features.

SummaryWe present a case of 45 years old female patient with two primary cerebral hydatid cysts, each localised in separate hemispheres. Detailed studies revealed no evidence of hydatid disease elsewhere in the body. The cysts were removed by two separate operations. Though the cyst in the right posterior parietal lobe was delivered unruptured, seven months later a new cyst was detected in the same cavity, which seems to show relatively rapid growth in a year, and was also removed unruptured.This case is presented here for its unusual features such as having two primary cerebral hydatid cysts simultaneously in separate hemispheres, one of which partly localised intraventricularly, and the occurrence of a new cyst in the same cavity following intact removal of the previous cyst.

eNOS G894T Polymorphism and Abdominal Aortic Aneurysms

Background: The genetic risk factors that contribute to the risk of developing abdominal aortic aneurysm (AAA) are poorly understood. We assessed the association of endothelial nitric oxide synthase (eNOS) gene polymorphism with AAA. Methods: eNOS gene polymorphism of 61 patients with AAA and 62 control participants were analyzed by polymerase chain reaction (PCR)-restriction technique. Results: eNOS G894 homozygote T/T genotype polymorphism and 894T allele frequency in patients with AAA were significantly higher than those of the control participants (P = .01, P = .03). Among patients with AAA, the eNOS G894 T/T polymorphism and 894T allele frequency were associated with larger AAAs. Conclusion: The current study, in a small group of participants, showed a relationship between eNOS G894T polymorphism and AAA.

Intracisternal versus intracarotid infusion of L-arginine in experimental cerebral vasospasm

AIM The effect of short term intracisternal and intracarotid L-arginine infusion on experimental cerebral acute phase vasospasm in a rabbit subarachnoid haemorrhage model is investigated, and the two groups compared. MATERIALS AND METHOD Subarachnoid haemorrhage was produced by intracisternal injection of autologous blood in New Zealand rabbits. On the fourth day after subarachnoid haemorrhage, cerebral blood flow was monitored using transcranial Doppler ultrasonography during intracisternal and intracarotid saline and L-arginine infusions. RESULT Cerebral blood flow measurements revealed resolution of vasospasm with short-term intracisternal and intracarotid L-arginine infusion. No significant difference was found between the effects of intracisternal and intracarotid L-arginine infusions, however intracarotid L-arginine infusion created a more potent vasodilatation towards the end of infusion. CONCLUSION Both intracisternal and intracarotid short term L-arginine infusion significantly improve acute phase cerebral vasospasm after experimental subarachnoid haemorrhage. Intracarotid L-arginine infusion is more potent and safer as large amounts of intracisternal L-arginine may lead to overproduction of nitric oxide by inducible nitric oxide synthase with the production of free radicals.

The effects of the electrical stimulation of the nasal mucosa on cortical cerebral blood flow in rabbits

The cerebral vessels have sympathetic, parasympathetic, and sensory innervations. A sensory innervation of the cerebral vessels originating in the trigeminal ganglion has been described in a number of species by several investigations. It has been shown that the electrical stimulation of the trigeminal ganglion causes an increase of cerebral blood flow (CBF). The aim of our present study is to stimulate the trigeminal ganglion with an extracranial and non-invasive method. A stimulating electrode was put in the nasal mucosa via right nares of rabbits and trigeminal ganglion was stimulated orthodromically via nasociliary nerve (NCN). Variations in the cortical CBF were evaluated by laser Doppler flowmetry. In experiment group, CBF increased together with the beginning of electrical stimulation. The flow values were remained high as long as the stimulation. In post-stimulation period, the CBF was decreased gradually and returned to the baseline values at 120s. This study demonstrated that the electrical stimulation of the NCN branch of the trigeminal nerve increases the cortical CBF under physiological conditions.