Influence of Meteorological Conditions on the Incidence of Chronic Subdural Haematoma, Subarachnoid and Intracerebral Haemorrhages - the "Bleeding Weather Hypothesis".

AIM: To elucidate possible causal relationships on climate change and intracranial haematomas. MATERIAL AND METHODS: In a retrospective study we examined all patients (N=1169) treated for subarachnoid haemorrhage (SAH; n=484), intracerebral haemorrhage (ICH; n=417) or chronic subdural haematoma (CSDH; n=268) in our department over a 7-yearperiod between 1st June 2005 until 31th May 2012. The date of admission was correlated with the corresponding meteorological parameters which included; mean daily temperature (°C), relative humidity (%), vapor pressure (hPa), barometric pressure (hPa), cloud amount (/8), and wind speed (m/s). RESULTS: Incidence of SAH tended to increase in April, ICH in January and CSDH in July, respectively, but ?² test did not reveal any statistical significance in seasonality for the three bleeding pathologies. Comparing the arithmetic average of meteorological key parameters of uneventful and eventful days by using student?s t-test within the three groups (SAH, ICH, CSDH) we could not demonstrate any statistical significance (p > 0.05). For SAH, logistic regression analyses revealed an increased risk associated with a decrease of barometric pressure (p=0.021). CONCLUSION: Although our data suggest seasonal variabilities of SAH, ICH and CSDH, the single weather parameters do not demonstrate causal relationships with the incidence of cerebrovascular events. However, incidence of SAH tended to increase with changes of barometric pressure which confirms previously published results and might indicate a possible underlying relationship.

Dynamic ICG fluorescence provides better intraoperative understanding of arteriovenous fistulae.

BACKGROUND: Sufficient perfusion is crucial during and after vascular neurosurgical procedures. Intraoperative indocyanine green (ICG) angiography has evolved into a useful tool in aneurysm and arteriovenous malformation surgery. Semiquantitative ICG fluorescence analysis Flow 800 may, in addition, lead to a better understanding of local perfusion. OBJECTIVE: We report the applicability and utility of semiquantitative ICG fluorescence in the surgical treatment of 5 patients with pial or dural arteriovenous fistulae. METHODS: Five patients with pial or dural arteriovenous fistulae were operated on using intraoperative semiquantitative ICG fluorescence Flow 800 (5 mg ICG bolus via central venous line). Before and after occlusion of fistulae, rise time of parenchyma and transit time from artery to parenchyma were measured. RESULTS: The analysis of flow parameters allowed detection of small fistulae and revealed a significant change in flow dynamics in the draining vein after surgical occlusion. ICG "flow" analysis showed rise time and transit time to be significantly shorter comparing pre-occlusion with post-occlusion (P = .025 and P = .039, respectively), leading to a significantly enhanced perfusion of neighboring brain parenchyma. CONCLUSION: In all 5 patients, dynamic analysis of fluorescence revealed a better understanding of intravascular rheology intraoperatively, allowing confident identification and treatment of pathology. Dynamic ICG fluorescence measurements provide additional perfusion information about flow characteristics in the draining vein and tissue perfusion, which facilitates surgical treatment of arteriovenous fistulae.

Good clinical practice in dubious head trauma - the problem of retained intracranial foreign bodies.

OBJECTIVE: In young people, traumatic head and brain injuries are the leading cause of morbidity and mortality. In some cases, no neurological deficits are present, even after penetrating trauma. These patients have a greater risk of suffering from secondary injuries due to secondary infections, brain edema, and hematomas. We present a case report which illustrates that brain injuries that do not induce neurological deficits can still result in a fatal clinical course and death, with medicolegal consequences. CLINICAL PRESENTATION: A 19-year-old patient was admitted to hospital suffering from a head injury due to an assault. He reported that he was attacked from behind. Medical examination showed no neurological deficits, and only a small occipital wound. Neuroimaging of the cranium revealed that a knife blade was penetrating the cranial bone and touching the superior sagittal sinus. INTERVENTION: After removing the foreign body, magnetic resonance imaging showed that the superior sagittal sinus remained open. CONCLUSION: We want to stress that possible problems can arise due to the retention of objects in the cranium, while also highlighting the risk of superficial clinical examination.

Meningiomas in pregnancy: a clinicopathologic study of 17 cases.

BACKGROUND: Dramatic growth of meningiomas is occasionally encountered during pregnancy. While cell proliferation is often assumed, hemodynamic changes have also been touted as a cause. OBJECTIVE: We identified 17 meningiomas resected during pregnancy or within 3 weeks post-partum and characterized them to determine the cause of occasional rapid growth in pregnancy. METHODS: Seventeen tumors were identified from searches at 4 university centers. All available clinical records, radiology images, and tissue specimens were reviewed, with immunohistochemical studies performed as needed. RESULTS: Sixteen patients underwent tumor resection and 1 died of complications prior to surgery. Average patient age was 32 years. Nine experienced onset of symptoms in the third trimester or within 8 days post-partum. Principle physical findings included visual complaints (59%) and cranial nerve palsies (29%). Ten tumors (59%) were located in the skull base region. The Ki-67 labeling index was low (0.5-3.6%) in 11 of 13 benign (grade I) tumors and elevated (11-23.2%) in 3 of 4 atypical (grade II) meningiomas. Eight (50%) tumors featured hypervascularity with at least focal CD34-positive hemangioma-like microvasculature. Fourteen (82%) showed evidence of intra- and/or extracellular edema, 1 so extensive that its meningothelial nature was not apparent. Five tumors (29%) exhibited intratumoral hemorrhage and/or necrosis. CONCLUSION: Our series suggests that pregnancy-associated meningiomas located in the skull base are likely to require surgical intervention for visual complaints and cranial nerve palsies. The rapid tumor growth is more often due to potentially reversible hemodynamic changes rather than hormone-induced cellular proliferation.

Histopathological analysis of intracerebral hemorrhage: implications for clinical management.

BACKGROUND: The clinical impact of routine neuropathologic examination of samples from patients with intracerebral hemorrhage (ICH) is unclear. METHODS: Therefore, we evaluated a consecutive series of 378 surgical specimens from patients with ICH concerning demographic data, localization of hemorrhage, preoperative clinical diagnosis and neuropathological diagnosis. RESULTS: Histological examination revealed the putative origin of ICH in 143 cases (37.8%). Vascular pathologies were detected in 127 patients (33.6%), while tumors were identified in 9 patients (2.4%), infarction in 6 patients (1.6%) and abscess in 1 patient (0.3%). Preoperatively, tumor was considered in 65 patients (17.2%), while vascular malformations were supposed in 94 patients (24.9%), infarction in 18 cases (4.8%) and abscess in 3 cases (0.8%). In 198 patients (52.4%) no specific assumption was made. CONCLUSIONS: Comparing preoperative assumptions and histological diagnoses, tumor, vascular malformations and infarctions were clinically overestimated, while arteriolosclerosis and amyloid angiopathy were underestimated. In conclusion, we found that histological findings potentially affecting clinical management and prognosis were obtained in 37.8% of cases. Our data suggest that histopathological examination of intracerebral hemorrhage provides important information for patient management and should be routinely performed.

Rationale of hyperbaric oxygenation in cerebral vascular insult.

Cerebrovascular diseases and especially ischemic stroke are a leading cause of death. They occur mostly due to an insufficient oxygen (O2) supply to the central neural tissue as a result of thromboembolic events and/or obstructive vessel disease. The primary damage of the brain tissue cannot be restored. However, adequate therapy could minimize secondary impairment of brain tissue and restore neuronal function in the so-called "penumbra region". Apart from reopening occluded vessels, additional O2 supply is essential for survival of malfunctioning neural tissue. Breathing of 100% O2 under hyperbaric conditions, hyperbaric oxygenation (HBO), is the only method to increase the O2 concentration in tissue with impaired blood supply. Experimental as well as clinical studies have reported a positive effect of HBO therapy. Survival rate has increased under HBO therapy and neurological outcome has improved. The optimal levels of pressure as well as duration and numbers of HBO sessions need to be specified to avoid undesirable effects. Unfortunately, many questions remain unanswered before routinely recommending HBO as additional therapy in clinical practice. In this review we consider the (patho-)physiological background of HBO-therapy, the latest results of experimental and clinical studies and stress the evidence in patients with cerebrovascular disease.

Prognostic value of histopathological findings in aneurysmal subarachnoid hemorrhage.

OBJECT: Aneurysmal subarachnoid hemorrhage (SAH) carries a severe prognosis, which is often related to the development of cerebral vasospasm. Even though several clinical and radiological predictors of vasospasm and functional outcome have been established, the prognostic value of histopathological findings remains unclear. METHODS: Histopathological findings in resected distal aneurysm walls were examined, as were the clinical and radiological factors in a series of 91 patients who had been neurosurgically treated for aneurysmal SAH. The impact of the histological, clinical, and radiological factors on the occurrence of vasospasm and functional outcome at discharge was analyzed. RESULTS: Histopathological findings frequently included lymphocytic infiltrates (60%), fibrosis (60%), and necrosis (50%) of the resected aneurysm wall. On univariate analysis, clinical (Hunt and Hess grade) and radiological (aneurysm size) factors as well as histopathological features-namely, lymphocytic infiltrates and necrosis of the aneurysm wall-were significantly associated with the occurrence of vasospasm. On multivariate analysis, lymphocytic infiltrates (OR 6.35, 95% CI 2.32-17.36, p = 0.0001) and aneurysm size (OR 1.22, 95% CI 1.05-1.42, p = 0.009) remained the only factors predicting the development of vasospasm. A poor functional outcome at discharge was significantly associated with vasospasm, other clinical factors (Hunt and Hess grade, alcohol consumption, hyperglycemia, and elevated white blood cell count [WBC] at admission), and radiological factors (Fisher grade and aneurysm size), as well as with histopathological features (lymphocytic infiltrates [p = 0.0001] and necrosis of the aneurysm wall [p = 0.0015]). On multivariate analysis taking into account all clinical, radiological, and histological factors; vasospasm (OR 9.82, 95% CI 1.83-52.82, p = 0.008), Hunt and Hess grade (OR 5.61, 95% CI 2.29-13.74, p = 0.0001), patient age (OR 1.09, 95% CI 1.02-1.16, p = 0.0013), elevated WBC (OR 1.29, 95% CI 1.01-1.64, p = 0.04), and Fisher grade (OR 4.35, 95% CI 1.25-15.07, p = 0.015) best predicted functional outcome at discharge. CONCLUSIONS: The demonstration of lymphocytic infiltrates in the resected aneurysm wall is of independent prognostic value for the development of vasospasm in patients with neurosurgically treated aneurysmal SAH. Thus, histopathology might complement other clinical and radiological factors in the identification of patients at risk.