Long-term outcome in posterior cerebral artery stroke.

INTRODUCTION: Previous studies on posterior cerebral artery (PCA) strokes focused mainly on topography and underlying pathophysiology. However, there are no data on long-term prognosis and its association with the localization of the infarct. METHODS: All consecutive PCA strokes registered in the Athens Stroke Outcome Project between 01/1998 and 12/2009 were included in the analysis. The New England Posterior Circulation Registry criteria were applied to classify them in relation to topography: (i) pure PCA infarcts, including pure cortical-only and combined cortical/deep PCA infarcts (groups A and B respectively), and (ii) PCA-plus strokes, including cortical-only and combined cortical/deep PCA strokes with ≥1 concomitant infarcts outside PCA territory (groups C and D respectively). Patients were prospectively followed up to 10 years after stroke. RESULTS: Amongst 185 (8.1%) PCA patients that were followed up for 49.6±26.7months, 98 (53%), 24 (13%), 36 (19.5%), and 27 (14.6%) were classified in group A, B, C, and D, respectively. Infections and brain edema with mass effect were more frequently encountered in PCA-plus strokes compared to pure PCA (P<0.05 and <0.01 respectively). At 6 months, 56% of cortical-only PCA patients had no or minor disability, compared to 37%, 36%, and 26% in the other groups (P=0.015). The 10-year probability of death was 55.1% (95%CI: 42.2-68.0) for pure PCA compared to 72.5% (95%CI: 58.8-86.2) for PCA-plus (log-rank 14.2, P=0.001). Long-term mortality was associated with initial neurologic severity and underlying stroke mechanism. CONCLUSIONS: Patients with pure PCA stroke have significantly lower risk of disability and long-term mortality compared to PCA strokes with coincident infarction outside the PCA territory.

Serum levels of S-100B after recreational scuba diving.

Recreational scuba diving is a sport of increasing popularity. Previous studies indicating subtle brain injury in asymptomatic divers imply a cumulative effect of minor neural insults in association with diving for professional and/or recreational purposes, over the long-term. This is the first study to investigate putative neural tissue burden during recreational scuba diving by measuring circulating levels of S-100B, a sensitive biomarker of brain injury. 5 male divers performed 3 consecutive dives under conservative recreational diving settings (maximum depth 15 m, duration of dive 56 min, ascend rate 1.15 m/min) with an interval of 12 h between each session. Although a small increase in serum S-100B levels after each dive was apparent, this increase did not quite reach statistical significance (p=0.057). Moreover, no abnormal S-100B values were recorded (mean baseline: 0.06 µg/L, mean post-dive: 0.086 µg/L) and no effect of the 3 consecutive dives on changes in S-100B levels was detected. These results suggest that under the experimental conditions tested, diving does not seem to have a discernible and/or cumulative impact on central nervous system integrity. The extent to which variable diving settings and practices as well as individual susceptibility factors underlie putative neural tissue burden in asymptomatic divers, remains to be established.

Serum biochemical markers of brain injury.

The diagnosis and assessment of brain damage is currently based on the clinical examination and the modern neuro-imaging techniques. Electrophysiology, haemodynamic monitoring and invasive neuromonitoring constitute additional tools for monitoring of the brain function and clinical course of the patient. However, despite the substantial progress, clinical and neuro-monitoring methods are quite often not sufficient to evaluate and quantify the severity of the initial and secondary destructive processes and hence they cannot guide efficient therapeutic measures and prognosticate effectively the outcome. During the last decades, researchers and clinicians have focused on specific markers of brain cell damage to improve the diagnosis and monitoring of neurological insults. Lactate dehydrogenase, creatine kinase, neuron specific enolase, have been proposed as potential markers of brain injury. More recently, other glial markers such as the Myelin Basic Protein, the glial fibrillary acidic protein and the S-100B protein have been measured in blood and used as surrogate biochemical markers for brain injury. This review summarizes published findings on the above brain specific serum biochemical markers with emphasis on those with clinical utility.

Cervical disc, mimicking nerve sheath tumor, with rapid spontaneous recovery: a case report.

The study design includes a case report and clinical discussion. The potential of acute disc herniations to regress spontaneously has been previously reported. However, the initial radiological presentation can be misleading, leading to therapeutic pitfalls, especially when the presence of myelopathy calls for early intervention. We present the case of a 46-year-old woman with a cervical intraspinal enhancing mass, associated enhancement of the C6 root and myelopathy, leading to the presumptive diagnosis of a nerve sheath tumor. The patient was offered surgery, which she denied. The patient returned 7 weeks later with significant clinical improvement. A subsequent magnetic resonance imaging depicted a herniated cervical disc and regression of myelopathy. Although spontaneous regression of disc prolapse and myelopathy have been previously reported, the initial radiological presentation and the short period of regression in this case highlight the need for a thorough understanding of the natural course of cervical disc herniations. Nonsurgical conservative observation should be considered an option for treatment for some cervical disc herniations that are likely to regress for very specific and predictable reasons.

Trigonal cavernous angioma: a short illustrated review.

PURPOSE: Intraventricular cavernomas are rare. Even more rare are those presenting in the trigone of the lateral ventricles. METHODS: We performed a search of the literature of the last 30 years and identified all cases of intraventricular cavernous angiomas. Trigonal cavernomas were separately identified and analysed. Our search yielded a total of 13 trigonal cavernomas. RESULTS: Of a total of 61 intraventricular cases, 13 were located in the trigone of the lateral ventricles. The most prominent presenting symptom was intracranial hypertension (68.9%), followed by seizures (18.2%) and hemorrhage (13.1%).The literature review revealed a trend of intraventricular cavernomas to present with intracranial hypertension rather than seizures or focal neurologic deficit, unlike their intraparenchymal counterparts. We feel that this difference has received little attention in the international literature. We discuss a possible pathogenetic mechanism for the presence of intracranial hypertension and address different aspects of diagnosis and treatment of this benign lesion. CONCLUSIONS: Trigonal cavernomas are benign lesions that have an excellent outcome after radical excision. Symptoms and signs of intracranial hypertension and hydrocephalus may be the prominent initial presentation of this rare ailment.

Recurrence of trigeminal neuralgia due to an acquired arachnoid cyst.

We present the case of a 55-year-old female with pain recurrence after microvascular decompression for trigeminal neuralgia due to development of an arachnoid cyst. Radioimaging studies were inconclusive for vascular compression but showed evidence of fifth nerve distortion. The patient underwent surgical re-exploration, and a cystic lesion of thickened arachnoid containing cerebrospinal fluid was identified and excised. Postoperatively, the patient obtained pain relief. Arachnoid cyst formation may be a possible reason for pain recurrence after microvascular decompression for trigeminal neuralgia, especially when repeat neuroimaging does not show clear evidence of fifth nerve vascular compression. Direct compression from the cyst or arterial pulsation transmission through the cyst to the nerve may be the cause of recurrence.

The current range of neuromodulatory devices and related technologies.

The pace of technology dictates changes in every aspect of human life. Medical profession is not an exception. The development of sophisticated electronic devices has radically influenced diagnosis and therapy. Today neurosurgical science is revolutionized with numerous implanted and non-implanted devices that modulate and stimulate the nervous system. Physicians, patients and non-technical experts involved in this field need to understand the core mechanisms and the main differences of this technology so that they can use it effectively. It will take years until clinicians reach a "consensus" about the use of these devices, but in the course of action objective information about the current status of the methods and equipment, and the technical, biological, and financial complications that arise in practice will speed up their public approval and acceptance.

The prognostic value of serum S-100B protein in spontaneous subarachnoid haemorrhage.

BACKGROUND: Despite the major progress in neurophysiological monitoring, there are still difficulties in the early identification and quantification of cerebral damage after a stroke. In this prospective study we examined the associations between serum S-100B protein, a serum marker of brain injury, and initial neurological-neuroimaging severity, secondary deterioration, external ventricular drainage (EVD: therapeutic intervention) and outcome in patients with subarachnoid haemorrhage (SAH). METHOD: We recorded all pertinent clinical data of 52 patients with SAH and measured S-100B serum levels on admission and every 24 h for a maximum of 9 consecutive days. Mann-Whitney U-test and Kruskal Wallis analysis were employed to assess the association of S-100B levels with all variables of interest. Log-rank test was used to evaluate survival and Cox's proportional hazard regression analysis to define the significant predictors of survival rate. FINDINGS: Admission S-100B was statistically significantly associated with initial neurological status, neuroimaging severity, and one-year outcome (p = 0.0002, 0.001, and 0.017, Kruskal Wallis analysis). Admission S-100B above 0.3 microg/L predicted unfavourable outcome (p < 0.0001, log rank test) and constituted an independent predictor of short-term survival (p = 0.035 Cox's proportional hazard regression analysis) with a hazard ratio of 2.2 (95% C.I.: 1.06-4.6) indicating a more than doubling of death probability. Secondary neurological deterioration associated with S-100B increase (p < 0.0001) and external ventricular drainage (EVD) with S-100B reduction (p = 0.003, Wilcoxon signed rank test). CONCLUSIONS: Serum S-100B protein seems to be a useful biochemical indicator of neurological - neuroimaging severity, secondary deterioration, EVD (therapeutic intervention), and outcome in patients with SAH.

Arachnoiditis ossificans with progressive syringomyelia and spinal arachnoid cyst.

We present a 30-year-old man with progressive spastic paraparesis. Spinal imaging revealed extensive calcification of the thoracic cord and cauda equina arachnoid, an intradural extramedullary cyst and evidence of rapidly progressing syringomyelia. Radiological diagnosis was arachnoiditis ossificans and an attempt at surgical decompression was made because of progressive neurologic deterioration. Due to tenacious adhesion of the calcified plaques to the cord and roots, only cyst drainage was achieved; the patient had no clinical improvement. A literature review revealed only two other cases reported in the literature with co-existence of arachnoiditis ossificans and syringomyelia. In none of the previous cases was there an intradural extramedullary arachnoid cyst, nor did the syrinx progress in such a rapid fashion. An attempt is made to explain possible pathophysiological mechanisms leading to this unusual pathology.

Serum S-100B protein as a biochemical marker of brain injury: a review of current concepts.

S-100 protein, described initially by Moore, constitutes a large family of at least 20 proteins with calcium binding ability. It is found as homo- or hetero-dimers of two different subunits (A and B). Types S-100AB and S-100BB are described as S-100B protein and are shown to be highly specific for nervous tissue. It is present in the cytosol of glial and Schwann cells, and also in adipocytes and chondrocytes, although in very low concentrations in the latter two. The role of protein S-100B is not yet fully understood. It is suggested that it has intracellular and extracellular neurotropic as well as neurotoxic function. At nanomolar levels, S-100B stimulates neurite outgrowth and enhances survival of neurons. However, at micromolar levels it stimulates the expression of inflammatory cytokines and induces apoptosis. Recently, serum S-100B protein has been proved to be an attractive surrogate marker of primary severe brain injury and secondary insults. It can be measured in the arterial and venous serum; it is not affected by haemolysis and remains stable for several hours without the need for immediate analysis. Its short half-life makes measurements crucial in the emergency and intensive care settings. This review summarises published findings on S-100B regarding its role as a serum biochemical marker of brain injury, i.e., after severe, moderate or mild neuro-trauma, subarachnoid haemorrhage, thrombo-embolic stroke, cerebral ischaemia and brain tumours, as well as extracranial trauma, neurodegenerative and psychiatric disorders.

Selection of cranial site for shunting debilitated patients.

BACKGROUND/OBJECTIVE: The optimum cranial site for ventricular catheter insertion in CSF shunts is still under debate and there has been no general consensus as far as surgical technicalities are concerned. Furthermore, there have been no reports dealing with appropriate cranial site selection in debilitated patients. The aim of this report is to stress the need to utilize a frontal approach when dealing with patients who are likely to remain bed-bound for long periods and to emphasize the well-known prerequisites such as meticulous surgical technique and peri-operative general and local care. METHOD: A retrospective analysis of all shunt operations and revisions performed in our department during the last 6 years. FINDINGS: This analysis revealed 8 long-term recumbent patients with late valve extrusion (N1 = 5) or primary wound breakdown (N2 = 3), all through the occipital area. Extended periods of bed rest due to neurological disease combined with poor nursing and dietary intake had led to either chronic valve extrusion or wound breakdown. Shunt revision was performed successfully by a frontal approach in 5 whereas 2 tolerated shunt removal and one died of meningitis. CONCLUSION: In debilitated patients or those who are likely to remain bed-bound for long periods, a frontal approach for proximal catheter insertion may help prevent immediate postoperative wound breakdown or late valve extrusion.

Development of neurosurgery in Greece: past, present, and future.

In this study the authors examine the historical tradition as well as current features of neurosurgery in Greece and compare the available data with international standards. In particular, they describe the organizational structure of neurosurgery with reference to manpower, unit distribution, training, and qualification. They discuss problems such as overproduction of neurosurgeons and the poor control of training and qualification procedures in the neurosurgical profession. The findings are examined in a critical way and solutions are proposed that could improve the present situation.

The overproduction of neurosurgeons jeopardizes future neurosurgical care.

In some areas of the world the next generation of neuro-surgeons is facing a serious problem. The training of an inappropriately large number of neurosurgeons will lead to underemployment/unemployment, which will have a direct impact on the quality of neurosurgical care. The following statistical data relate to local phenomena but reflect dilemmas to be considered by the international neurosurgical community since they exist in many countries.

Peritumoural haematoma and meningioma: a common tumour with an uncommon presentation.

Spontaneous peritumoural haemorrhage in meningiomas is a rare but serious complication with a grave prognosis. It occurs at the interface between the tumour and the parenchyma, either from the tumour surface or the cortical vessels in association with it. Although several pathophysiologic mechanisms for this complication have been proposed, they all remain speculative. We report a 72-year-old female who presented with sudden onset of headache and a left homonymous hemianopia. Neuroimaging revealed a parasagittal meningioma at the posterior third of the superior sagittal sinus with peritumoural intracerebral haematoma, 1 cm away from the tumour. An uncomplicated gross total excision of the meningioma and aspiration of the haematoma was achieved through a craniotomy. The postoperative course was uneventful with an excellent clinical outcome. Possible mechanisms for this unusual complication are discussed. We emphasise the importance of prompt diagnosis and simultaneous excision of the tumour and aspiration of the haematoma as prerequisites for a favourable outcome.

Functional outcome in patients after excision of extracanalicular acoustic neuromas using the suboccipital approach.

An audit of surgery for acoustic neuroma was carried out to determine the frequency and nature of postoperative symptoms and their impact upon the patient's quality of life and vocation. Fifty-six patients were interviewed between 6 months and 5 years (mean 26 months) after surgical excision of an acoustic neuroma. The objective surgical results in these patients are good, with normal or near normal functional preservation rates of 80% for the facial nerve (House-Brackmann grade I/II), and 27.3% for a previously functioning acoustic nerve. Despite this there was no significant overall reduction in the reported occurrence of balance problems, tinnitus, headache and other neurological sequelae of the tumour after surgical excision. In 20% of the patients persistent symptoms, including deafness and facial weakness, had prevented the resumption of former social activities. As a result of these symptoms 8.6% of the patients were certified medically unfit for work, but of those employed preoperatively over 70% had returned to their jobs. The success of neuro-otological surgical management of acoustic neuroma is offset by some degree of chronic morbidity. Our patients expressed the need to know whether their symptoms would resolve, but were often too afraid to ask. Patients can be reassured that the majority resume their former social and vocational activities, but should be advised that some symptoms can persist or occur de novo after surgery. Our data suggest that early intervention would reduce the incidence of these troublesome sequelae.

Higher Orexin A levels in lumbar compared to ventricular CSF: a study in idiopathic normal pressure hydrocephalus.

Orexin A (ORX-A) is implicated in the regulation of various physiological processes, including sleep/wake cycles and reward/motivation. The hypothalamic ORX-A neurons project throughout the brain and spinal cord. In the present study we established and compared ORX-A levels in lumbar and ventricular cerebrospinal fluid (CSF) samples, drawn from idiopathic normal pressure hydrocephalus (INPH) patients, during respectively, lumbar puncture and shunt placement. Ventricular and lumbar CSF levels of total protein and of the dopamine, serotonin and norepinephrine metabolites HVA, 5-HIAA and MHPG respectively, were also estimated. ORX-A was quantified using a commercially available radioimmunoassay kit. Neurotransmitter metabolites were quantified by high performance liquid chromatography. Expectedly, HVA and 5-HIAA levels were significantly higher and total protein levels lower in ventricular compared to lumbar CSF while there were no differences in MHPG levels. However, in contrast to HVA and 5-HIAA and similar to total protein, lumbar ORX-A levels were significantly higher than ventricular levels. The higher lumbar compared to ventricular ORX-A levels may reflect elevated contributions from the spinal cord. The finding of a ventriculo-lumbar difference for ORX-A should be considered in studies utilizing its CSF levels in assessing Orexin system status.