Pituitary dysfunction after aneurysmal subarachnoid hemorrhage.

Patients recovering from aneurysmal SAH often complain about weakness, fatigue and impaired cognitive skills. Pituitary dysfunction might be one possible reason for these complaints, as in patients with traumatic brain injury, hypopituitarism is known to be a common complication. There are only a few studies dealing with this problem in SAH patients, but these studies suggest that pituitary disturbances are very frequent after aneurysmal SAH. But anterior pituitary lobe disturbances might not be the only one responsible for some complaints or complications in patients suffering from aneurysmal SAH. Hyponatremia in the early state after SAH could be a hint for posterior pituitary lobe dysfunction.

Ultrasonic blood flow volume assessment in the extracranial internal carotid artery in arteriovenous malformations.

Angle-independent ultrasound assessment of the volume flow in the extracranial internal carotid artery (ICA) is a new approach to evaluate the perfusion status of the human brain. Normal values using a new technical device (Quantix ND, Cardiosonix Ltd, Israel) and correlation analysis to quantitative CBF measurements were recently published. Aim of this study was to evaluate this device in arteriovenous malformations where cerebral blood flow is known to be increased. Five patients suffering from large supratentorial arteriovenous malformations (AVM) could be examined. All patients showed pre-operatively elevated flow volumes in the internal carotid artery on the side harbouring the pathological lesion compared with normal values evaluated in 50 volunteers. The contralateral internal carotid artery showed volume flow values within the normal limit. After surgical resection of the malformation normal values could be measured in all patients. Pathological elevated increases in cerebral blood flow can be evaluated by ultrasonic blood flow volume assessment in the extracranial internal carotid artery. Therefore, the Quantix ND seems a valuable tool in diagnosing cerebral hyperemia.

Monitoring of cerebral oxygen metabolism in the jugular bulb: reliability of unilateral measurements in severe head injury.

To investigate the reliability of unilateral jugular venous monitoring and to determine the appropriate side, we performed bilateral jugular venous monitoring in 22 head-injured patients. Fiberoptic catheters were placed in both jugular bulbs. Arterial and bilateral jugular venous blood samples were obtained simultaneously for in vitro determination of jugular venous oxygen saturation (SJO2), arterial minus jugular venous lactate content difference (AJDL), and modified lactate-oxygen index (mLOI). Ischemia was assumed if one of the following pathologic values occurred at least unilaterally: SJO2 <54%, AJDL <-0.37 mmol/L, mLOI >0.08. The sensitivity of calculated unilateral monitoring in detecting ischemia was evaluated by comparing the incidence detected unilaterally with that disclosed bilaterally. The mean and maximum bilateral SJO2 differences varied between 1.4% and 21.0%, and 8.1% and 44.3%, respectively. The bias and limits of agreement (mean differences +/- 2 SD) between paired samples were 0.4% +/- 12.8%. There was no significant variation in bilateral SJO2 differences with time. Decreasing cerebral perfusion pressure (r = -0.559, P < 0.001) and arterial PCO2 (r = -0.342, P < 0.001) were associated with increasing bilateral SJO2 differences. Regarding AJDL, the maximum bilateral differences varied between 0.04 mmol/L and 1.52 mmol/L. The bias and limits of agreement were -0.01 +/- 0.18 mmol/L. At best, 87% of ischemic events were disclosed by monitoring on the side of predominant lesion or, in diffuse injuries, on the side of the larger jugular foramen (computed tomographic [CT] approach). We conclude that in severe head injury, even calculated unilateral jugular venous monitoring has an unpredictable risk for misleading or missing data. Therefore, the reliability of unilateral jugular venous monitoring appears suspicious. For diagnosing ischemia the CT approach is recommended.

Neuron-specific enolase serum levels after controlled cortical impact injury in the rat.

The aim of this study was to investigate the time course and the correlation of neuron-specific enolase (NSE) serum levels to the severity of traumatic brain injury in rats. Sixty-five male Wistar rats were subjected to severe cortical impact injury (100 PSI, 2 mm deformation). Blood samples were drawn directly after trauma and after 1, 6, 12, 24, and 48 h in the trauma group. In the sham operated levels animals samples were drawn directly after craniotomy and after 6 and 48 h. Additionally, NSE serum levels after controlled cortical impact at different levels of severity samples (45 PSI, 75 PSI; 2 mm deformity) were compared to sham-operated animals. The severity of the injury was not validated histopathologically. NSE serum levels were estimated with a commercially available enzyme immunoassay (LIA mat Sangtec). The control animals showed a NSE serum level of 8.82 microg/L (mean, n = 10) and the injured animals demonstrated a time-dependent release of NSE into the serum. The highest NSE serum values were detected 6 h after trauma (31.5 microg/L mean, n = 10). In addition, we found a close relationship between NSE serum levels and the severity of traumatic brain injury in the cortical impact model. NSE serum levels reflect in a time-dependent manner the severity of brain trauma induced by cortical impact model in rat.

Prognostic factors of posterior cervical disc surgery: a prospective, consecutive study of 54 patients.

OBJECTIVE: To our knowledge, there is no prospective study to date about the prognostic factors of dorsal foraminotomy. The aim of this prospective study was to provide further information in this field. METHODS: From January 1994 to January 1995, we performed a prospective, consecutive study of 54 patients, each of whose lateral herniated cervical disc was operated on via a dorsal foraminotomy. We analyzed the general data, the case history, the neurological examination at admission, and all data from imaging examinations and therapy. Most of the patients (93%) were followed up at 1 year, postoperatively. The patients were divided into one group with good results and another group with bad results, according to their ratings on a pain scale. The groups were analyzed in relation to the patients' initial condition. RESULTS: At follow-up, 94% of the patients had completely recovered or their condition had improved. CONCLUSION: A long duration of preoperative complaints and a long-standing neurological deficit seem to be important prognostic factors for a bad outcome after dorsal foraminotomy.

Influence of macrophage infiltration of herniated lumbar disc tissue on outcome after lumbar disc surgery.

STUDY DESIGN: An immunohistochemical examination of the presence of inflammatory cells in routinely processed resection specimens of the lumbar disc, and a comparison of the histologic results with clinical data collected prospectively before and after surgery. OBJECTIVES: To assess the influence of inflammatory reactions in herniated lumbar disc specimens on the outcome after lumbar disc surgery. SUMMARY OF BACKGROUND DATA: Histologic and biochemical studies on herniated lumbar disc tissue led to the notion of inflammation-induced sciatic pain. At this writing, no investigations have sought to discover how outcome after lumbar disc surgery is influenced by histologically described inflammation. METHODS: Disc specimens from 79 patients who underwent surgery for lumbar disc herniation were studied immunohistologically with regard to the presence of inflammatory reactions. Of these, 92% were followed up approximately 7 months after surgery. The histologic results were compared with the outcome at follow-up evaluation. RESULTS: A statistically significant correlation was found between the histologically proven inflammation and the outcome, as shown by the pain grading scale. CONCLUSIONS: The results from this study seem to support the theory of a foreign body reaction to the herniated material. This reaction may result in inflammation-induced sciatic pain.

Is there a clinical correlate to the histologic evidence of inflammation in herniated lumbar disc tissue?

STUDY DESIGN: The presence of inflammatory cells was examined immunohistochemically in routinely processed resection specimens of the lumbar disc. The histologic results were compared with prospectively obtained clinical data. OBJECTIVES: To assess the clinical relevance of inflammatory cells in herniated lumbar disc specimens. SUMMARY OF BACKGROUND DATA: It is postulated that in addition to nerve root compression, an inflammatory stimulus of the herniated lumbar disc is responsible for sciatic pain and radiculopathy. However, the clinical relevance of the histologically described inflammatory infiltrates is not defined clearly. METHODS: Disc specimens from 44 patients who underwent surgery for lumbar disc herniation were studied immunohistologically. Before surgery, severity of pain was classified in each patient according to a visual analog scale, and general clinical data were recorded prospectively. RESULTS: Varying amounts of inflammatory cells could be demonstrated in the resected disc tissue. In the statistical analysis, no statistically significant correlation between the histologic evidence of macrophage infiltrates and the pain grading scale or the clinical data was noted. CONCLUSIONS: There is no statistically significant correlation between macrophage infiltrates in herniated lumbar disc specimens and the obtained clinical data.

Variability of outcome after lumbar disc surgery.

STUDY DESIGN: A prospective, consecutive study of patients' outcome at three subsequent follow-up times after lumbar disc surgery. OBJECTIVES: To evaluate how consistent outcome remained in a group of patients after lumbar disc surgery. SUMMARY OF BACKGROUND DATA: Despite similar results concerning the overall outcome, results in most studies show different prognostic factors for lumbar disc surgery at different follow-up times. A reason for this observation could be that patients shift to a different outcome group during the observation period. METHODS: Before surgery and at the three follow-ups (3, 12, and 28 months after surgery) the Low Back Outcome Score was calculated. Groups with favorable and unfavorable outcome were determined after each follow-up according to the scores. RESULTS: Ninety-eight patients were studied. Forty percent showed an unstable outcome at different follow-up times. For each follow-up, three prognostic factors were determined. No prognostic factor showed significance at all follow-up examinations. CONCLUSIONS: Patients whose outcome after lumbar disc surgery does not remain stable present a major problem in the calculation of prognostic factors.

Clinical signs in patients with brachialgia and sciatica: a comparative study.

BACKGROUND: The aim of the study was to compare the clinical signs of patients with cervical and lumbar root affections. METHODS: From January 1994 to January 1995, we performed a prospective study on 395 patients. The study comprised 93 patients with a cervical and 302 patients with a lumbar root affection. 338 patients underwent surgery. General data, case histories, and neurological findings were analyzed. RESULTS: The patients with brachialgia had a nonradicular pain radiation in 67%, the patients with sciatica only in 35%. All other data showed no significant differences. The investigation also shows that a radicular pain radiation is significantly correlated with an unequivocal radicular deficit. In particular, the patients with a cervical radicular pain radiation had a highly significant incidence of a radicular neurological deficit. CONCLUSIONS: We could demonstrate in this prospective study that only about one third of the patients with a cervical root affection showed an unequivocal radicular pain radiation. This contradicts the traditional medical textbook concept of a cervical root compression syndrome. This difference in respect of the clinical signs of lumbar and cervical root compressions might be explained by the anatomical variations of cervical root anastomoses. To determine the affected cervical root level, further investigation of the myotomes is recommended.

Time profile of neuron specific enolase serum levels after experimental brain injury in rat.

The aim of this study was to investigate the time course of NSE serum levels after traumatic brain injury in rats. 65 male Wistar rats were subjected to severe cortical impact injury (100 PSI, 2 mm deformation). Blood samples were drawn directly after trauma, after 1 h, 6 h, 12 h, 24 h, and 48 h in the trauma group as well as in sham operated animals directly after craniotomy, after 6 h and after 48 h. NSE serum levels were estimated with a commercially available enzyme immuno assay (LIA-mat Sangtec). The control animals showed a NSE serum level of 8.82 micrograms/l (mean, n = 10). We demonstrated a time dependent release of NSE into the serum after trauma. The highest NSE serum values were detected six hours after trauma (31.5 micrograms/l, mean, n = 10). NSE serum level seems to reflect neuronal damage after cortical contusion in the rat in a time dependent manner.

S-100 serum levels and outcome after severe head injury.

S-100B a protein of astroglial cells is described as a marker for neuronal damage. Reliable outcome prediction from severe head injury is still unresolved. Clinical scores like the Glasgow Coma Score (GCS) and diagnostic scores like the Marshall CT Classification (MCTC) are well established and investigated, but there are still some concerns about these tools. The aim of this study was to investigate the predictive value of the initial serum level of S-100B. 44 patients with severe head injury (GCS < 9) were included. Blood samples were drawn within 1 to 6 hours of injury. After a period of 11 months their outcome was correlated using the Glasgow Outcome Scale. Patients with good outcome had significantly lower serum concentrations of S-100 on admission (0.96 microgram/l versus 5.5 micrograms/l mean, p < 0.0001). In addition patients with a S-100 serum level below 2 micrograms/l showed a significant better rating on the GOS at follow-up (4 points versus 1.8 points mean, p < 0.0001). With this cut-off line it was possible to predict longterm outcome with a sensitivity of 75% and specitivity of 82%. The serum level of S-100B calculated with one to six hours of a severe head injury is a useful additional outcome predictor.

Glial and neuronal serum markers after controlled cortical impact injury in the rat.

The aim of this study was to investigate the time course and the correlation of glial fibrillary acidic protein (GFAP), protein S-100B, and neuron specific enolase (NSE) serum levels to the severity of traumatic brain injury in rats. Male Wistar rats (n = 65 S-100B, NSE group and n = 55 GFAP group) underwent a severe cortical impact injury (100PSI, 2 mm deformation). Blood samples were drawn directly after trauma, 1 h, 6 h, 12 h, 24 h, and 48 h post trauma as well as in sham operated animals directly after craniotomy, after 6 h and 48 h. Serum levels at different severities were estimated in 20 rats (45PSI, 75PSI, 2 mm deformation). We found a time-dependent release of NSE and GFAP into serum after trauma. The highest NSE values were detected six hours after trauma (31.5 micrograms/l, mean, p < 0.0001), the highest GFAP levels were measured one hour after trauma (0.079 microgram/l, mean, p < 0.0014). Additionally we found a close relationship between NSE serum levels and the severity of traumatic brain injury (45PSI = 12.7 micrograms/l, 75PSI = 16.17 micrograms/l, 100PSI = 28.45 micrograms/l, p < 0.05). S-100B serum levels showed an increase (0.92 microgram/l, p < 0.005) but no time-dependent release. S-100B and GFAP showed no relationship to trauma severity. Serum levels of GFAP, S-100B and NSE are significantly elevated in the early phase after experimental traumatic brain injury. In this experimental model of cortical impact injury only NSE, but not GFAP and S-100B serum levels are time-dependently correlated with the severity of cortical impact.

Dynamic correlation between tissue PO2 and near infrared spectroscopy.

Multimodal O2 monitoring including tissue pO2 measurements and near infrared spectroscopy (NIRS) are techniques increasingly employed for monitoring patients on neurosurgical intensive care units. NIRS measures a mixed venous arterial oxygen saturation, whereas tissue pO2 evaluates the oxygen pressure in the white matter. In contrast to the tissue pO2 measurements, the NIRS at the moment has not been completely established in clinical practice. We wanted to evaluate whether both techniques are monitoring different dynamic changes. Thirteen patients were included (SAH n = 3, TBI n = 10), 12 patients were male and 1 was female. Mean age was 34 years with a range from 16-76 years. Tissue pO2 probes (Licox, GMS, Germany) were implanted in the frontal lobe showing most pathological changes on the initial CT scan. A near infrared spectroscopy sensor (Invos, Somanetics, USA) was placed simultaneously at the patient's forehead. Due to the drift of the tissue pO2 probe, only data sets were taken into further account in which a tissue pO2 value above 15 mmHg was measured. 66 data sets were analyzed by calculating the spectral coherence with multi taper methods. The coherence of two independent white noise signals were defined as an observation by chance. The significance level for correlated frequencies was 90%. In the spectral long time regime (frequency > or = 0.02), more than 80% of the data sets showed a higher percentage of correlated frequencies as compared to the observation by chance. The assumption that tissue pO2 and near infrared spectroscopy probes are measuring different dynamic changes in neurosurgical intensive care patients could not be supported by our data.

Long term outcome after cervical foraminotomy.

We recently demonstrated the effectiveness of dorsal foraminotomy in lateral herniated cervical disc after 1 year follow-up in a prospective study.(1) The goal of this paper is to confirm these results concerning long term outcome. We carried out a prospective, consecutive study on 54 patients, operated on for lateral herniated cervical disc. We analysed demographic data, the case history, the neurological examination on admission and imaging data. Ninety per cent were followed up for 3.5 years postoperatively. According to their ratings on a pain scale the group were divided into favourable and unfavourable outcomes. These groups were analysed in relation to the patient's initial condition. At follow up, 90% of patients showed complete recovery or improvement. A long standing preoperative neurological deficit seems to be an important prognostic factor for unfavourable long term outcome after cervical foraminotomy.

Cognitive decline as an important sign for an operable cause of dementia: chronic subdural haematoma.

BACKGROUND: Cognitive decline, slow psychomotor regression and confusion, especially in the elderly, often result in medical consultation. Frequently, these rather unspecific symptoms are interpreted as signs of beginning dementia. When mental regression is joined by tremor or motor deficits, neurodegenerative disease is commonly considered and the need for neuroimaging is underestimated. Chronic subdural haematoma (CSH) is known to be the most frequent type of intracranial bleeding, appearing mostly in the elderly after minor trauma with unspecific symptoms. The aim of this retrospective study was the identification of the leading clinical symptoms in patients with the diagnosis CSH who had been treated surgically in our Neurosurgical Department. PATIENTS AND METHOD: 356 patients with symptomatic CSH (225 male, 131 female; mean age 68.3 years), who were admitted to our Neurosurgical Department between 1992 and 2003, were included in the study. We reviewed the charts documenting preoperative clinical status, radiological signs, history of trauma, operative complications, postoperative clinical status, days of hospitalisation as well as gender and age. RESULTS: The primary surgical procedure performed in 343 patients (96.4%) was burr-hole trepanation. The leading preoperative symptoms were mnestic deficits (cognitive decline, confusion) in 192 patients (55.8%), followed by headache in 150 patients (45.5%) and motor deficit in 144 patients (41.1%). Furthermore, we found a statistically significant correlation (p<0.005) between the thickness of the left-sided haematoma and the symptoms aphasia and psychosyndrome. CONCLUSION: The leading clinical symptoms identified in our cohort were mnestic deficits, headache and motor deficit, signs that mostly appear at the beginning of demential diseases. Thus, CSH should be taken into account as an important differential diagnosis for demential and neurodegenerative diseases and neuroimaging should be demanded. Once a CSH is detected this way, the patient should be transferred to a neurosurgical department where an easy standard procedure may potentially lead to early recovery.

A study of possible correlation between subarachnoid haemorrhage related vasospasm and the post-bleed blood platelet count chart in a Caucasian population.

INTRODUCTION: There has been controversy about the aetiology and pathophysiology of subarachnoid haemorrhage (SAH) related vasospasm. Several pathogenic factors like endothelin and adhesion molecules have been discussed. A recently published study concerning an exclusively Asian population suggested a relationship between SAH related vasospasm and the blood platelet count. The aim of our study was to examine this relationship in a European population. METHOD: We carefully reviewed 88 patients with aneurysmal SAH (54 females, 34 males; mean age 52.5 years, range from 22 to 78 years) treated in our centre with regard to the occurrence of vasospasm and the blood platelet count in a ten day interval after initial SAH. Symptomatic vasospasm was defined as a focal neurological deficit or deterioration in the level of consciousness with or without confirmation of infarction on a CT scan. Thirty-seven patients (42%) developed clinically relevant vasospasm. RESULTS: There was no statistically significant correlation between the blood platelet count chart (maximum and minimum values) and vasospasm or clinical outcome; we also found no gender or age-related influence on the above mentioned relationships. CONCLUSIONS: In our opinion there appears to be a difference between Caucasian and Asian populations regarding the influence of platelets in the pathophysiology of SAH and vasospasm.

Cerebrospinal fluid and neutrophil respiratory burst after subarachnoid hemorrhage.

OBJECTIVES: To investigate the effect of cerebrospinal fluid (CSF) from patients with subarachnoid hemorrhage (SAH) on the activation of polymorphonuclear neutrophils (PMN) in response to receptor-dependent stimulation with N-formyl-l-methionyl-l-leucyl-l-phenylalanine and TNFalpha or non-receptor-dependent stimulation with phorbol 12-myristate 13-acetate. METHODS: CSF from 12 patients with SAH due to ruptured cerebral aneurysm was collected. Samples of CSF were drawn at different time points. CSF from 6 healthy subjects receiving spinal anesthesia served as the control group. After stimulation of PMN the generation of reactive oxygen intermediates was analyzed on a flow cytometer. RESULTS: In the presence of CSF, PMN showed a significant suppression of the oxidative burst following stimulation compared to stimulation without CSF. The reduction of the oxidative burst following stimulation was higher in the presence of CSF from patients with SAH. After pretreatment at 56 degrees C, the extent of the suppression observed following receptor-dependent stimulation and CSF from patients with SAH was similar to that seen after stimulation with CSF from healthy individuals. CONCLUSIONS: These data show that the presence of CSF resulted in a suppression of neutrophil oxidative function. A more distinct depression was seen in the presence of CSF from patients with SAH. We suggest a complex physiological inhibitory and protective mechanism against unfavorable activation of PMN by CSF.

S-100B protein serum levels after controlled cortical impact injury in the rat.

S-100B is described to provide information about the severity of brain damage in man. Estimation of serum markers appears to be an easy method of obtaining information regarding severity and outcome after head injury. However less is known about the post traumatic time course of this protein in the serum. The aim of this study was to provide further information about the posttraumatic enzymekinetik. 65 male Wistar rats were subjected to severe cortical impact injury (100 PSI, 2 mm deformation). Blood samples were drawn directly after trauma, then after 1 h, 6 h, 12 h, 24 h, and 48 h. In sham operated animals blood samples were drawn directly after craniotomy, then after 6 h and after 48 h. Also compared were S-100B serum levels at different severities in 20 rats (45 PSI, 75 PSI; 2 mm deformity) after controlled cortical impact to sham operated animals. S-100B serum levels were estimated with a commercially available enzyme immuno-assay (DAKO). The mean serum level in the sham group was 0.38 microg/l. Serum levels at 100 PSI differed statistically significantly directly after trauma up to 24 h. The 48 h S-100B levels showed no significant difference in the sham group. Serum levels at different severities differed significantly from the sham group, but did not differ concerning level of severity. The controlled cortical impact model is able to produce a raised serum level of the S-100B protein for 24 hours. Different trauma severities were not reflected.