Biomedical subjects
Publications and source records attributed to U Schick.
We report a patient in whom a bullet in the brain migrated into the pineal region causing hydrocephalus 3 months later. In patients undergoing surgical removal of intracerebral or intraventricular bullets, it is recommended to obtain an x-ray or CT scan on the day of operation. Late hydrocephalus may occur several months after migration of the bullet due to scar tissue.
OBJECTIVE: Changes in evoked potentials (EPs) and increased levels of S-100B protein were used to identify cerebral ischemia or glial damage and to predict neurological outcome in aneurysm patients. MATERIAL AND METHODS: Somatosensory evoked potentials and Brainstem auditory-evoked potentials, and serum S-100B protein were simultaneously investigated pre- and postoperatively over a period of 10 days in 43 patients with 47 aneurysms (six in the posterior fossa). RESULTS: The EP scores showed a strong correlation with the clinical outcome. Sensitivity was 73%, and specificity 81%. Pathological S-100B levels >0.5 mg/l were equal in predictive values (correct positive eight, false positive six, correct negative 26, false negative three). Initially increased S-100B levels, long-lasting S-100B elevation, and secondary increasing S-100B values correlated with an unfavorable outcome. High peak S-100B values correlated with bad EP scores at discharge. EP deterioration was the first indicator anticipating S-100B elevation and clinical deterioration in five patients. There was a good correlation between pathological S-100B values or EP findings and infarction on CT scan. CONCLUSIONS: Both EPs and S-100B protein showed a comparable high predictive value for outcome. S-100B reflects the extent of primary brain damage after subarachnoid hemorrhage and time course of ongoing secondary brain damage. Evoked potentials assess the functional integrity and tended to react earlier than S-100B protein before definitive structural damage occurred.
OBJECTIVE: The coincidence of coagulatopathy and chronic subdural haematoma (CSH) requires correction of coagulation to facilitate surgery. We investigated the correlation between coagulopathy and outcome in CSH patients. MATERIAL AND METHODS: We analysed past medical history, surgical treatment and coagulation parameters of 114 patients. RESULTS: Coagulation disorders were found in 42%. Preoperative treatment with prothrombin complex concentrate was necessary in 14%. A significant difference (P < 0.05) of the preoperative level of platelets was found between recurrent CSH and non-recurrent group. Totally, we had to perform re-operations in 17.5%. Eighty-one patients presented with Glasgow coma scale (GCS) > or = 13. After surgery GCS was > or = 13 in n = 92. There was an improvement of GCS in 46 cases, 61 patients maintained GCS score levels. Outcome was significantly worse in the alcoholic group (P < 0.001), and in the recurrent group (P < 0.05). In patients with substitution of coagulation factors, outcome was worse in the group with post-operative substitution only (P < 0.05). CONCLUSION: In CSH, the coagulation parameters and a subtle correction of coagulation are of special interest, regarding the worse outcome in patients with recurrent CSH and in those requiring post-operative substitution.
Spinal dural arteriovenous fistula (dAVFs) are rare and often misdiagnosed entities. The choice between surgical treatment and embolization remains a matter of debate. We report on the cases of 18 patients (16 men, 2 women) with dAVF, who were treated surgically over an 11-year period. Patient age ranged from 32 to 84 years (mean 60 years). Six patients underwent embolization preoperatively. In three cases, angiography examinations failed to show feeding arteries on first examination at neuroradiological centers. Feeding arteries were at a different level than the fistula point in seven patients, two of them presenting with new anastomoses after embolization. Location of the fistula was midthoracic to lumbar. Seven patients were variously misdiagnosed with tumor, polyneuropathy, Guillain-Barré syndrome, syringomyelia, and knee disease. Clinical history was characterized by slowly progressive and fluctuating deterioration. Initial symptoms were mainly sensory loss and motor weakness, lasting for between 4 and 45 months before diagnosis (mean 15 months). Recurrent fistula after operation was found in one patient. In another patient, control angiography revealed a fistula at another level, and in a third, a fistula on the contralateral side. All three patients underwent reoperation. Temporary clinical deterioration was found in four patients, seven remained unchanged, and seven improved postoperatively. An attempt at embolization should be made following diagnostic angiography. Otherwise, surgery is our recommended treatment for spinal dural fistulas, as it has a lower failure rate. Because of the progressive natural course with severe deficits, we favor an early definitive treatment.
This study investigated electromyographic (EMG) activity as a marker of nerve root irritation during two different surgical procedures for lumbar disc herniation. Mechanically elicited EMG activity was recorded during the dynamic stages of surgery in muscle groups innervated by lumbar nerve roots. Confirmation of surgical activity was correlated with the activity of the electromyogram. Fifteen patients with lumbar disc herniations were treated via an endoscopic medial approach, and 15 patients via the open microscopic surgical technique. Results indicated that the endoscopic technique was superior to the open surgical technique and produced less irritation of the nerve root. Significantly less mechanically elicited activity was recorded during both the approach and the root mobilization. The study showed that microendoscopic discectomy allows a smaller incision and less tissue trauma with comparable visualization of the nerve structures than does open surgery.
Various percutaneous techniques to approach the lumbar disc were studied in the past. Chemonucleolysis, laser vaporization, lateral endoscopic foraminal approaches and different techniques of percutaneous nucleotomy remained disappointing due to insufficient root visualization, insufficient decompression or insufficient disc removal. The microendoscopic discectomy is performed via a median approach that allows thorough root exploration, direct evaluation of the compression and determination of contained or non-contained disc material. This is achieved by applying open surgical tools through a tubular retractor under endoscopic visualization. The endoscope is inserted via a sequential set of dilators passed over the initial guide wire. The technique allows a smaller incision and less tissue trauma with comparable visualization of the nerve structures than does standard open surgery.
Intradural spinal metastases are uncommon. The outcome of surgical treatment of intra- and extramedullary intradural metastases is considered to be poor, with rapid clinical deterioration. The question of optimal treatment remains controversial. We present an overview of the clinical outcome and surgical treatment of 220 spinal metastases carried out in our centre from 1980 to 1999, with particular emphasis on 11 intradural metastases. Clinical history, signs, surgical approach, outcome, and radiological reports were obtained by review of patient charts. Secondary spinal tumours most often originated from carcinomas of the breast, lung, kidney, gastrointestinal tract, and prostate. In 12% of cases, no primary tumour could be found. Drop metastases of intracranial pathology appeared in 3%. Intradural metastases were seen in 11 patients and formed a very heterogeneous group with predominance of melanoma, lymphoma, and medulloblastoma. Functional recovery and survival time were worse in intradural metastases than in extradural metastases, and the patients were younger. Treatment of metastases is designed to relieve pain and preserve or restore neurological function palliatively. Intradural metastases are a devastating condition with usually fatal outcome. Selected patients who undergo aggressive surgical treatment may have substantially increased survival.
The outcome of surgical treatment of benign spinal neoplasms is considered to be excellent, with good improvement of neurological function. The risk of recurrence is estimated to be very low, except with subtotal resections. This retrospective study was designed to establish the course of illness, clinical outcome, and recurrence rate of benign spinal tumours. We present an overview of the clinical outcome and surgical treatment of 197 benign spinal tumours carried out in our centre from 1980 to 1999. Clinical history, signs, surgical approach, outcome, and radiological reports were obtained by reviewing patient charts. The most frequent benign tumour was meningeoma (41%), closely followed by neurinoma (33%) and neurofibroma (6.1%). Of all tumours, 79.7% were completely resected. Recurrence happened in 10.2% on an average of 4.3 years postoperatively. Only 2 patients suffered from neurofibromatosis. All neurinomas were completely resected at first operation, whereas three out of seven recurrent meningeomas and all ependymomas were classified as subtotally resected. Seventy per cent were treated by repeated surgical intervention. Benign tumours usually can be completely removed without adding to patients' neurological deficits. Benign tumours recur in 10.2% of cases, thus requiring long-term follow-up. Magnetic resonance imaging (MRI) studies are recommended up to 5 years postoperatively as a routine procedure.
We present an overview of the clinical outcome and surgical treatment of 34 pediatric spinal tumors, carried out in our center from 1981 to 1999. Follow-ups were available for 25.5 months on average. Clinical history, signs, surgical approach, outcome and radiological reports were obtained by review of the patients' charts. These pediatric tumors formed a very heterogeneous group, with a predominance of neurinomas and neurofibromas in older children and neuroblastomas or primitive neuroectodermal tumors in younger ones. Ependymomas and astrocytomas were the most frequent intramedullary tumors. Extradural tumors included tumors such as aneurysmal bone cysts, Ewing's sarcoma, histiocytomas, chordomas and an angiofibroma. Following decompression of the spinal cord, the neurological status improved with good functional recovery in 23 children and had deteriorated at follow-up in 5 children. Relapse occurred in 12 cases, including histiocytomas, chordomas, medulloblastoma and tumors associated with genetic disorders. Eighteen children underwent a combined treatment with chemotherapy and/or radiotherapy. The spectrum of pathology is wide and requires multidisciplinary treatment.
A CT-based method of marking superficial intracranial lesions with a needle is presented. This form of neuronavigation can be applied in every neurosurgical centre. Owing to its rapid application it is also suitable for cases of emergency. The neurosurgical approach can be centred precisely over the lesion providing for a minimally invasive operation. The method has proved its efficacy in numerous cases of haematomas and cystic lesions.
We describe a patient who developed a brain abscess 52 years after sustaining a penetrating craniocerebral shrapnel injury. For 10 years he had suffered from diabetes mellitus, a disorder known to predispose to infections from a diminished body defence. The treatment and aetiology of this rare occurrence is discussed.
OBJECTIVES: To evaluate the long term sequelae of perimesencephalic subarachnoid haemorrhage (PMSAH). METHODS: Twenty one consecutive patients were studied. All patients were examined by CT, angiography, MRI, multimodal evoked potentials, and transcranial Doppler sonography. All relevant clinical data during hospital stay and outcome at discharge were obtained by reviewing the charts. Long term follow up was evaluated by reviewing the outpatient files and dedicated outpatient review. Patients were specifically questioned about their perceived recovery, residual complaints, and present occupational status. RESULTS: Apart from the initial CT confirming the diagnosis of PMSAH all other examinations disclosed no abnormalities. None of the patients developed any complications during hospital stay, and all patients were discharged in good clinical condition and without neurological deficits. At long term follow up 62% of the patients had residual complaints consisting of headaches, irritability, depression, forgetfulness, weariness, and diminished endurance. Apart from four patients who had already retired before the PMSAH, only seven of the remaining 17 patients (41%) returned to their previous occupation, whereas nine patients (53%) retired from work and one man became unemployed. One patient had a recurrence of PMSAH 31 months after the first event. CONCLUSION: PMSAH can have considerable long term psychosocial sequelae, and may also recur. Prognosis may not be as good as previously reported.
This study was designed to compare the effect of a mechanical vs a pharmacologic increase in BP on coronary artery blood flow and thrombolysis induced by IV administration of recombinant tissue plasminogen activator. We employed a canine model of coronary thrombosis induced by injection of radioactive blood clot in the left anterior descending coronary artery. Subsequently, all dogs underwent phlebotomy to decrease systolic BP to 75 mm Hg and this decreased coronary blood flow by 50%. BP was increased to 130 mm Hg by norepinephrine (NE) infusion or by inflation of a Fogarty catheter placed in the descending aorta. Interventions with NE or with a Fogarty balloon catheter increased coronary artery blood flow to similar values and rates of coronary thrombolysis were similar. However, cardiac output was significantly higher with NE. These results indicate coronary clot lysis is dependent on perfusion pressure and coronary blood flow, not cardiac output.
20% of all spine injuries are cervical spine injuries. Surgical treatment of these injuries must take into account the great mobility of this part of the spinal column. Therefore, biomechanical aspects must be considered, especially in the upper cervical spine-C1 and C2. Describing our own therapeutical regimen in 35 patients with unstable upper cervical spine injuries we explain the biomechanical back-ground and review the literature. It becomes evident that ventral approaches are superior to dorsal techniques for decompression, reposition, and stabilization with minimal loss of mobility.
The EC-IC Bypass Study Group could not detect any benefit from surgery compared to medical management in the prevention of stroke in 1985 [15]. During the past years surgical revascularization was re-evaluated and considered as an appropriate treatment for a small subgroup of patients with recurrent focal cerebral ischaemia and impaired haemodynamics. This retrospective study examines the long-term benefit and patency rate of bypass. We present a follow-up of 5.6 years of 47 patients, all of whom underwent bypass surgery after 1985. Forty patients suffered recurring transient ischaemic attacks due to uni- or bilateral internal carotid artery occlusion. Examination included neurologic status, TCD with CO2 or Diamox challenge, angiography, CT and SPECT scans. Neurological improvement was seen in 23% of patients with better results after early surgery, a worsening in 22% suffering further ischaemic events on a postoperative average of 2.8 years. Patency rate for vein graft material was 50%, for the STA-MCA procedure 91%. Occlusion of the vein graft occurred on an average after 1.4 years, other anastomosis after 2.7 years. We conclude that only few patients derived long-term benefit from EC-IC bypasses. Functioning of the bypass worsens over time, suggesting a role for surgery predominantly in the first year of ischaemic events due to insufficient collateral supply. Actual indications for bypass surgery may be patients with failure of maximal medical therapy and progressive ischaemia and haemodynamic compromise.
This study was designed to compare the efficacy of coronary thrombolysis obtained with i.v. administration of three dose regimens of recombinant tissue plasminogen activator (rtPA). Although many studies have confirmed the efficacy of thrombolytic therapy in treatment of acute myocardial infarction, few prospective studies have been designed to determine which dose regimen optimizes the rate of coronary thrombolysis. A canine model was used. Coronary thrombosis was induced by injection of radioactive, autologous blood clots through a catheter placed in the left anterior descending coronary artery. Subsequently, 15 dogs were randomized into 3 groups of 5 dogs each. In group 1 dogs, 1.25 mg/kg of rtPA was administered i.v. as a bolus; in the group 2 dogs, 1.25 mg/kg of rtPA was administered over 60 min. The administration was "front loaded" so that 15% was administered as a bolus, 60% over 30 min, and 25% over 30 min; in group 3, 1.25 mg/kg of rtPA was divided into two i.v. boluses and administered 15 min apart. Coronary thrombolysis was assessed with a gamma camera. Despite differences in rate of administration of rtPA, at 15, 30, and 90 min after onset of treatment, extent of clot lysis was similar between groups. These results indicate that despite differences in dose regimens, rates of thrombolysis are similar when i.v. rtPA is relatively rapidly administered. Further, the similar rates of clot lysis over time between groups suggest both an effective upper limit to the dose-thrombolytic rate relationship and relatively high, sustained steady-state plasma concentrations of rtPA.
PURPOSE: Our study investigated the effects of an increase in aortic pressure, induced by norepinephrine (NE) administration on coronary artery flow in a clotted artery, and rate of coronary thrombolysis induced by intravenous (i.v.) administration of recombinant tissue plasminogen activator (rtPA). METHODS: A canine model of coronary thrombosis, induced by intracoronary injection of radioactive autologous blood clots, was used to test the hypothesis that an increase in aortic blood pressure will increase coronary artery flow and the rate of clot lysis induced by i.v. administration of rtPA. RESULTS: After clot injection, 11 dogs were phlebotomized to decrease systolic aortic pressure to 75 mm Hg. Subsequently, .25 mg/kg of rtPA was administered intravenously over two 15-minute intervals, one during hypotension, and the other after NE infusion had increased systolic blood pressure to 130 mm Hg. In six dogs the hypotensive condition was studied first, and in five dogs the NE-induced normotensive condition was studied first. In all dogs, coronary artery flow and the rate of clot lysis were significantly increased in the normotensive condition. CONCLUSIONS: These results indicate that an increase in a low coronary artery perfusion pressure may enhance coronary artery flow and the rate of thrombolysis.