Choroid plexus papilloma of bilateral lateral ventricle.

BACKGROUND: Choroid plexus papillomas are rare, accounting for less than 1% of all intracranial tumours in adults. However, they are relatively more common in childhood and constitute 1.5 to 4% of intracranial tumours. They are most often located in the lateral ventricle, followed by the fourth and third ventricles and, rarely, in the cerebellopontine angle. Bilateral lateral ventricle choroid plexus papilloma is very rare and only a few cases has been reported. CLINICAL PRESENTATION: A 3-year-old boy was admitted to our hospital with a history of irritability and vomiting. Neurological examination on admission was normal. A head computed tomographic scan and magnetic resonance imaging showed tumours in both lateral ventricles, hydrocephalus and a left temporal arachnoid cyst. The bilateral intraventricular mass enhanced densely and homogeneously. A presumptive diagnosis of choroid plexus papillomas was made. INTERPRETATION: The initial surgery was performed for removal of the lesion in the right lateral ventricle, and 20 days later removal of the left lateral ventricle tumour was carried out. Bilateral temporoparietal craniotomy and total removal of tumours was performed. Hydrocephalus was controlled by total tumour resection from both sides. The histology of these tumours was the same and revealed choroid plexus papilloma. Interpretation: Bilateral choroid plexus papilloma is extremely rare and distinct from diffuse villous hypertrophy and their surgical approaches are different from each other. Differential diagnosis should be made by MRI preoperatively. If bilateral choroid plexus papilloma is detected, total surgical resection should be performed. Total surgical removal of the neoplasm not only cures the tumour but also may lead to complete resolution of the hydrocephalus.

The evaluation and comparison of cerebellar mutism in children and adults after posterior fossa surgery: report of two adult cases and review of the literature.

BACKGROUND: Although there are some cases of cerebellar mutism in adults after posterior fossa surgery for cerebellar tumour it generally occurs in children. Reversible pathophsiology and the anatomical substrate of this syndrome still remain unclear. The predominance of cerebellar mutism in children is suggested to be related to the higher incidence of posterior fossa tumours in children. However, the question regarding the reason for the obvious difference in the incidence of this syndrome between the paediatric and adult population still remaining unanswered. The aim of this study was to evaluate and compare children and adult groups separately to understand the incidence and the clinical characteristics better and to elucidate the pathophysiological basis and predictive factors for this syndrome. METHOD: We reviewed, analysed, and compared the cases of cerebellar mutism individually in children and in adults reported in the English literature. We found 106 reported cases in children and 11 cases in adults which were suitable for analysis. We added two adult cases to these. FINDINGS: The ages of the patients ranged from 2 to 16 (mean, 6.4 year) in children and from 17 to 74 (mean, 38.7 year) in adults. Although vermis was the main location in both groups, the incidence of vermis lesions was considered higher in the paediatric population (%91.5 versus %69.2). The rate of brain stem invasion was prominent in children (%31.1) when compared with adults (%7.6). The latency for the development of mutism and the duration of the mutism were similar in children and adults (mean, 1.4 d versus 2 d and mean, 5.07 wk versus 4.2 wk respectively). Mutism was transient in all the cases of both groups. INTERPRETATION: Recent concepts of cerebellar physiology disclose the importance of the cerebellum in learning, language, and mental and social functions. Pontine nuclei, the thalamus, motor and sensory areas and supplementary motor areas have been proven necessary for the initiation of speech. It can be hypothesized that uncompleted maturation of the reciprocal links in childhood connecting the cerebellum to these structure makes the children more vulnerable to have postoperative cerebellar mutism in comparison to the adult population.

Effects of trapidil on ATPase, lipid peroxidation, and correlation with ultrastructure in experimental spinal cord injury.

The present study was performed to investigate the effect of trapidil on ischemic damage of cells after spinal cord injury. The injury was produced by extradural clip compression of the exposed spinal cord in rats according to Rivlin and Tator. The ten rats in group 1 were used to determine normal findings without any surgery or medication. On the 15 rats in group 2, only six-level laminectomy was performed to determine the influence of the total laminectomy on the biochemical factors measured and the, light and ultrastructural findings. The 15 rats each in groups 3 and 4 were used as trauma and trapidil (40 mg/kg) treatment groups, respectively. The injury actually produced a significant decrease in Na+-K+/Mg+2 ATPase activity of the injured segments as early as 10 min after trauma. Trapidil attenuated Na+-K+/Mg+2 ATPase inactivation in the traumatized rats for 120 min after treatment (P<0.05) and significantly reduced the malone dialdehyde content below that in the traumatized group at all determined times (P<0.05). Light and electron microscopic findings supported the biochemical results.

Effect of anti-rat interleukin-6 antibody after spinal cord injury in the rat: inducible nitric oxide synthase expression, sodium- and potassium-activated, magnesium-dependent adenosine-5'-triphosphatase and superoxide dismutase activation, and ultrastructural changes.

OBJECT: The inflammatory cells that accumulate at the damaged site after spinal cord injury (SCI) may secrete interleukin-6 (IL-6), a mediator known to induce the expression of inducible nitric oxide synthase (iNOS). Any increased production of NO by iNOS activity would aggravate the primary neurological damage in SCI. If this mechanism does occur, the direct or indirect effects of IL-6 antagonists on iNOS activity should modulate this secondary injury. In this study, the authors produced spinal cord damage in rats and applied anti-rat IL-6 antibody to neutralize IL-6 bioactivity and to reduce iNOS. They determined the spinal cord tissue activities of Na+-K+/Mg++ adenosine-5'-triphosphatase (ATPase) and superoxide dismutase, evaluated iNOS immunoreactivity, and examined ultrastructural findings to assess the results of this treatment. METHODS: Seventy rats were randomly allocated to four groups. Group I (10 rats) were killed to provide normal spinal cord tissue for testing. In Group II 20 rats underwent six-level laminectomy for the effects of total laminectomy alone to be determined. In Group III 20 rats underwent six-level T2-7 laminectomy and SCI was produced by extradural compression of the exposed cord. The same procedures were performed in the 20 Group IV rats, but these rats also received one (2 microg) intraperitoneal injection of anti-rat IL-6 antibody immediately after the injury and a second dose 24 hours posttrauma. Half of the rats from each of Groups II through IV were killed at 2 hours and the other half at 48 hours posttrauma. The exposed cord segments were immediately removed and processed for analysis. CONCLUSIONS: The results showed that neutralizing IL-6 bioactivity with anti-rat IL-6 antibody significantly attenuates iNOS activity and reduces secondary structural changes in damaged rat spinal cord tissue.

The effects of the pre-treatment of intravenous nimodipine on Na(+)-K+/Mg+2 ATPase, Ca+2/Mg+2 ATPase, lipid peroxidation and early ultrastructural findings following middle cerebral artery occlusion in the rat.

Excessive calcium influx has been implicated in the pathophysiology of ischemic cerebral damage. The effects of nimodipine, a calcium antagonist, on the Na(+)-K+/MG+2 ATPase activity, Ca+2/Mg+2 ATPase, lipid peroxidation, and early ultrastructural findings were examined at the acute stage of ischemia in the rat brain. Ischemia was produced by permanent unilateral occlusion of the middle cerebral artery. In Group I, the rats which had no ischemia and not received medication were used for determining Na(+)-K+/Mg+2 ATPase, Ca+2/Mg+2 ATPase, the extent of lipid peroxidation by measuring the malondialdehyde content and normal ultrastructural findings. In Group II, the rats which had only subtemporal craniectomy without occlusion and received saline solution were used for determining the effect of the surgical procedure on the biochemical indices and ultrastructural findings. In Group III, the rats received saline solution following the occlusion in the same amount of nimodipine and in the same duration as used in Group IV. In Group IV, nimodipine pre-treatment 15 min before occlusion (microgram kg-1 min-1 over a 10 min period) was applied i.v. Na(+)-K+/Mg+2 ATPase and Ca+2/Mg+2 ATPase activities decreased significantly and promptly as early as 10 min and remained at a lower level than the contralateral hemisphere in the same group and at the normal level in Group I. Nimodipine pre-treatment immediately attenuated the inactivation of Na(+)-K+/Mg+2 ATPase (p < 0.05) but there was no change on Ca+2/Mg+2 ATPase activity (p < 0.05). Malondialdehyde content increased significantly in Group III following ischemia as early as 30 min. Nimodipine pre-treatment decreased the malondialdehyde level in Group IV (p < 0.05). This study supports the possibility that nimodipine pre-treatment effects the membrane stabilizing properties via inhibiting the lipid peroxidation and subsequently restoring some membrane bound and lipid dependent enzymes' activity such as Na(+)-K+/Mg+2 ATPase and the ultrastructural findings.

Postoperative radicular neuroma. Case report.

Lumbar discectomy is the most common surgical procedure performed in neurosurgery clinics. Such a large number of procedures underscore not only the prevalence of conditions such as intervertebral disc herniation, but also the strong belief of surgeons that the operation does provide benefits to patients suffering from sciatica. In spite of this belief, sciatic pain may continue after the surgery. The recurrence of sciatic and/or back pain after primary discectomy is called the "failed back surgery syndrome." The rate of the complications involved in standard lumbar discectomy ranges from 5.4 to 14%. One of the complications of the lumbar disc surgery is nerve root injury. The complication rate of this injury ranges from 0.7 to 2.2%. Postoperative radicular neuroma must be considered in differential diagnosis for the patient who has failed back surgery syndrome. In this study the authors evaluate a patient who had undergone surgery for lumbar disc herniation and suffered intractable pain. A traumatic radicular neuroma is demonstrated and the pertinent literature is presented.

Multiple anterolateral cervical meningoceles associated with neurofibromatosis.

In neurosurgical practice, the term 'spinal meningocele' is generally used to describe a congenital spinal malformation including protrusion of the spinal meninx from the congenitally dysraphic vertebrae. Although non-dysraphic meningocele is very rare, it is usually associated with neurofibromatosis or Marfan's syndrome in the literature. Thoracic and/or lumbar spinal levels are the most common localization. Anterolateral localization of meningocele is very rare in the cervical region. Operative treatment is indicated if the lesion is symptomatic. Detailed radiological assessment of the meningocele is necessary since it may be associated with neuroma in the sac. If the neuroma is found in the meningocele, an anterior surgical approach should be considered for the treatment of both of the lesions.

Huge meningiomas: a review of 93 cases.

Between 1972 and 1996, 450 consecutive patients with intracranial meningiomas were operated on at Cukurova University School of Medicine. By size, intracranial meningiomas were classified as huge (>6 cm minimum diameter when extrapolated to anatomic size) or not huge (<6 cm). The present study involves 93 patients who underwent 109 craniotomies for the removal of huge meningiomas. All patients are adult, with 31 men and 62 women or a 1:2 male to female ratio, with a mean age of 48.7 +/- 2.3 years at the time of diagnosis. The average duration of observed survival in 85 patients followed in the computed tomography (CT) era was 4.8 years and that of 8 patients in the pre-CT era was 8.8 years. Eleven patients died by the last follow-up assessment. Seventy-nine patients were still alive at the last follow-up assessment. The overall postoperative mortality rate was 3.2%. The overall recurrence rate was 19%. In descending order of frequency, the first five anatomic locations of the huge meningiomas were the parasagittal region in 18 patients (19.3%), the cerebral convexity in 15 (16.1%), the olfactory groove in 15 (16.1%), the falx in 12 (12.9%), and the tuberculum sellae in 11 (11.8%). The overall results of surgical treatment in 93 patients were total removal in 59 (63.4%), radical subtotal in 18 (18.3%), and subtotal in 16 (17.2%), with good outcome in 69 (74.1%), fair in 16 (17.2%), and poor in 5 (5.3%). In conclusion, the huge size of meningiomas affects the extent of removal, recurrence rate, postoperative outcome, operative morbidity and mortality rates, and survival time negatively.

The effect of collagen, interleukin-1 alpha and glicosaminoglycan on the neovascularization of central nervous system.

Neovascularization, the development of a new microvasculature, has an important role in physiological and pathological processes. The vascular changes in the brain can be easily detected because the proliferation of endothelial cells in its vascular structure is quite small, and so constitutes a good model for neovascularization studies. In the present investigation, to induce intracerebral neovascularization, we implanted collagen, Interleukin-1 alpha (IL-1 alpha) and glicosaminoglycan into the brain of pigs, in order to test the hypothesis that IL-1 alpha, collagen and glicosaminoglycan play a pivotal role in the process of neovascularization. Both pure collagen and collagen combined with IL-1 alpha induced neovascularization according to light-electron microscopic findings and values of enzymes' activities. In particular, collagen combined with IL-1 alpha synergically affected the increase of neovascularization. However, glicosaminoglycan did not affect it significantly. Although the results of this study provided us with some interesting data indicating the beneficial effects of collagen combined with IL-1 alpha on neovascularization, further studies should be done to study the short term effect of these biochemical substances.

The effect of trapidil on the reactive astrocytic proliferation following spinal cord trauma in rats: light and electron microscopic findings.

Platelet-derived growth factor (PDGF) released from platelets is one of the mitogens in serum, which plays a major role upon the cell biology, namely enhancing cell division and controlling of the maturation, especially upon the glial cell growth and its differentiation. Trapidil, which is an anti-PDGF agent, inhibits the effect of PDGF, especially the proliferative effects on the glial and tumoral cells in vitro. Previous studies suggested that the astrocytic proliferation stimulated by PDGF was inhibited by trapidil via the selective antagonism. Trapidil was not found to have a considerable effect on the prevention of nonpermissive astrocytes in this study. It should be theorized that trapidil, administered immediately even after the trauma, could not reach the injury site in effective measure because of secondary events such as edema and impairment of blood circulation. This suggestion should be another subject for studies concerning trapidil which is administered prior to the trauma.

A giant dissecting aneurysm mimicking serpentine aneurysm angiographically. Case report and review of the literature.

Intracranial dissecting and giant serpentine aneurysms are rare vascular anomalies. Their precise cause has not yet been completely clarified, and the radiological appearance of such lesions can be different in each case according to the effect of hemodynamic stress on a pathologic vessel wall. For berry aneurysms, available evidence overwhelmingly favors their causation by hemodynamically induced degenerative vascular disease and there is an obvious need to determine the hemodynamic parameters most likely to induce the precursor atrophic lesions. In this study, a case of a giant dissecting aneurysm angiographically mimicking serpentine aneurysm of the right ophthalmic artery is reported and the relevant literature is reviewed to investigate the pathological characteristics and pathogenesis of this lesion. In the present case, radiological investigation of the lesion suggested a serpentine aneurysm, but the diagnosis was corrected to dissecting aneurysm subsequent to the pathological examination of the resected aneurysm. A giant dissecting aneurysm angiographically mimicking serpentine aneurysm and developing as the result of a circumferential dissection located between the internal elastic lamina and media is of particular interest when the etiology of these aneurysms is considered. To our knowledge this is the first report on intracranial dissecting aneurysm mimicking serpentine aneurysm angiographically. Our case illustrates the importance of careful serial section studies for a better understanding of the vascular pathology underlying the processes involved in intracranial serpentine aneurysms. We conclude that serpentine, dissecting and berry aneurysms may all arise by way of similar pathophysiological mechanisms.

The effect of trapidil on the reactive astrocytic proliferation following spinal cord trauma in rats: Light and electron microscopic findings.

Platelet-derived growth factor (POCF) released from platelets is one ofthe mitogens in serum, which plays a major role upon the cell biology, namely enhancing cell division and controlling of the maturation, especially upon the glial cell growth and its differentiation. Trapidil, which is an anti-POCF agent, inhibits the effect of POCF, especially the proliferative effects on the glial and tumoral cells in vitro. Previous studies suggested that the astrocytic proliferation stimulated by POCF was inhibited by trapidil via the selective antagonism. Trapidil was not found to have a considerable effect on the prevention of nonpermissive astrocytes in this study. It should be theorised that trapidil, administered immediately even after the trauma, could not reach the injury site in effective measure because of secondary events such as edema and impairment of blood circulation. This suggestion should be another subject for studies concerning trapidil which is administered prior to the trauma. [Neural Res 1998; 20: 365-373].

The effect of thyrotropin releasing hormone on carbon dioxide laser induced lesion of the cerebral artery.

Carbon dioxide laser which is used widely in neurosurgery has less traumatic effect on the tissue beside the lesion than other types of laser. There has been little study on the changes to the vascular tissue, following laser application. We performed a study on 4 groups of dogs; comprising craniectomy only, craniectomy and thyrotropin releasing hormone (TRH), craniectomy and laser, and craniectomy, laser and TRH. We applied CO2 laser on the angular artery of two groups of dogs. To one group we infused TRH for 15 days following the laser application and to the other group we did not. We investigated the ultrastructural and biochemical changes and the effect of TRH on the tissue 15 days following laser application. In our study, we observed an increase in superoxide dismutase activity and a decrease in ATP-ase activities in the degenerated tissue on which CO2 laser was applied. TRH partially prevented the vascular degeneration of CO2 laser but did not significantly change superoxide dismutase and Adenosine-5'-triphosphatase activities.

Percutaneous radiofrequency rhizotomy of lumbar spinal facets: the results of 46 cases.

The results of percutaneous radiofrequency rhizotomy of lumbar spinal facets in 46 patients followed at least three months (mean 15 months) are reported and compared with those reported previously. Satisfactory pain relief three months after the procedure was achieved in 36.4 percent of patients without operations and in 41.7 percent of patients, with operations other than fusion. No patient had previously undergone fusion. Treatment of low-back pain by using radio-frequency thermocoagulation of spinal facets is a simple, safe, and well-tolerated procedure. It can be used to relief of pain in spite of decreasing rates of success within the follow-up period.

The effects of the pretreatment of intravenous high dose methylprednisolone on Na(+)-K(+)/Mg(+2) ATPase and lipid peroxidation and early ultrastructural findings following middle cerebral artery occlusion in the rat.

The sodium-potassium activated and magnesium dependent adenosine-5'-triphosphatase (Na(+)-K(+)/Mg(+2) ATPase EC.3.6.1.3.) activity and lipid peroxidation and early ultrastructural findings were determined in rat brain at the acute stage of ischaemia produced by permanent unilateral occlusion of the middle cerebral artery (MCA). The effects of the pretreatment with intravenous high-dose methylprednisolone (MP) on these biochemical indices and ultrastructural findings were also evaluated in the same model. The rats were divided into four groups. In group I, 10 rats were used to determine Na(+)-K(+)/Mg(+2) ATPase activity and the extent of lipid peroxidation by measuring the malondialdehyde (MDA) content and normal ultrastructural findings. In group II on 20 rats, only subtemporal craniectomy was done in order to determine the effects of the surgical procedure on these indices and findings. This group was treated intravenously with saline solution before occlusion. In group III with MCA occlusion, saline solution was administered intravenously to 20 rats in the same amount of methylprednisolone used in group IV, ten minutes before the occlusion. In Group IV, a single high-dose (30 mg/kg) of methylprednisolone was administered intravenously, ten minutes before occlusion in 20 rats. After occlusion of the middle cerebral artery, Na(+)-K(+)/Mg(+2) ATPase activity was decreased promptly in the first ten minutes in the ischaemic hemisphere and remained at a lower level than the contralateral hemispheres in the same group and the normal levels in group I, during 120 minutes of ischaemia. A single dose methylprednisolone pretreatment prohibited the inactivation of Na(+)-K(+)/Mg(+2) ATPase. On the other hand, there was significant difference in malondialdehyde content between group I and group III. Malondialdehyde levels were significantly increased following ischaemia and a non-significant increase was observed in the contralateral hemisphere. Methylprednisolone treatment significantly decreased malondialdehyde content on the side of the ischaemic hemisphere. We conclude that there is a positive relationship between membrane-bound enzyme Na(+)-K(+)/Mg(+2) ATPase activity, malondialdehyde content and early ultrastructural changes in the treated group with MP. These data suggest that the pretreatment injection of high doses (30 mg/kg) methylprednisolone contribute to the protection of the brain from ischaemia with stabilization of the cell membrane by effecting the lipid peroxidation and the activation of Na(+)-K(+)/Mg(+2) ATPase.

The effect of immediate decompression on the optic nerve in retrobulbar hematoma.

We produced retrobulbar hematoma in both orbits of 10 pigs in order to assess the effects of blood elements and pressure created by the hematoma on the optic nerves. Ten other pigs were used as a control group. Following decompression in the right orbits, ocular movements, fundi, and intraocular pressure were evaluated for 6 weeks. At the end of the 6th week the optic nerves of 20 pigs were dissected bilaterally for measurements of ATP-ase activity and ultrastructural examination. The results of the ultrastructural examination of the optic nerves of the control group were normal. Optic nerves with decompressed retrobulbar hematoma showed minimal degeneration, whereas the nerves subjected to retrobulbar hematoma with no decompression showed significant degenerative changes. For all groups ATP-ase activities were measured and evaluated. Na+, K+ ATP-ase activities decreased, while Ca+2, Mg+2 ATP-ase activities increased with the extent of degeneration. Optic nerve damage can develop after trauma. Decompression procedures are not among the causes of optic nerve degeneration but retrobulbar hematoma can result in optic neuropathy caused by the compression from the hematoma and the direct effect of blood waste products on the optic nerve.

Isolated trigeminal neuralgia secondary to distal anterior inferior cerebellar artery aneurysm.

A 43-year-old woman complaining of severe pain of the right side of the face was admitted to the Department of Neurosurgery. It had been present for three months and diagnosed as trigeminal neuralgia. The CT scan without contrast material had been considered normal at that time. Three months later, after a favourable response to carbamazepine, she suddenly developed right occipital headache and drowsiness. On admission, she was alert, and neurological examination revealed only mild neck stiffness. Computed tomographic scan demonstrated an acute hematoma in the right cerebellopontine angle and in the fourth ventricle. Vertebral angiography revealed an aneurysm of the right anterior inferior cerebellar artery (AICA). A posterior fossa approach disclosed a large, nearly totally thrombosed, saccular AICA aneurysm, which showed minimal compression to the pons at the trigeminal root entry zone. The aneurysm was clipped and excised. She showed an excellent recovery and was free of pain in the early postoperative period and at the last examination 16 months later. Aneurysms in the distal AICA are very rare lesions. Only 31 cases have been published so far. Distal AICA aneurysm in an extremely unusual cause of trigeminal neuralgia secondary to aneurysmal compression. The literature concerning AICA aneurysms and their clinical manifestations is reviewed and discussed.

Effect of dexamethasone, barbiturate and hypothermy on edema induced by CO2 laser brain lesion in the dog: light and electron microscopic study.

Experiments were carried out to compare the effectiveness of dexamethasone, a barbiturate, and hypothermy on experimental cerebral edema caused by CO2 laser in dogs. Experimental brain lesions were created over the right frontal cortex of the dogs through the intact dura mater with CO2 laser energy (40 W impact, 0.5 second duration, for a total time of 4 seconds on a 12.5 mm surface). Animals were divided into four groups and treated with dexamethasone, a barbiturate, hypothermy, and a crystalloid (control group). The brains were examined 48 hours after injury. Histologically all brain lesions showed three distinct layers with a vaporized center bordered by a zone of coagulation necrosis surrounded by edema. The main finding in the surrounding coagulation and edematous layers was dilatation of the vessels. Hemorrhage was sometimes observed mainly in the edematous layer. The effect of these therapies on the laser lesion and the effectiveness of these therapies on surrounding cerebral edema were evaluated by both light and electron microscopy. The control group showed significantly greater edema than the dexamethasone group. There was only a minimal difference between the control group and the barbiturate group, and there was no significant difference in amount of edema between control group and the hypothermy group. There was less edema in the dexamethasone group than in the other ones. These data suggest that dexamethasone inhibits edema in CO2 laser lesions with the same efficacy as shown in the treatment of vasogenic edema.

Intracranial arterial aneurysm complicating Behçet's disease.

Behçet's disease, a rare condition in central Europe but more common in Turkey where it was originally described, is characterized clinically by the presence of a diagnostic triad of oral and genital aphthous ulcers, meningitis, and relapsing iridocyclitis. Vascular lesions including arterial and venous occlusions, arterial aneurysms and varices are one of the common complications of Behçet's disease occur most commonly in the abdominal aorta, femoral arteries and pulmonary arteries. There have been only four reports of aneurysms of cerebral arteries in the literature. The authors describe a patient with Behçet's disease who suffered secondary subarachnoid hemorrhage due to a ruptured aneurysm of the anterior communicating artery 3 years after the initial diagnosis. This case report draws further attention to this rare entity in patients with Behçet's disease.