MRI-findings after uncomplicated anterior cervical discectomy.

BACKGROUND: The anterior approach for cervical discectomy with methacrylate-implant involves manipulations on vertebral bodies and ligaments. Foreign materials like methacrylate and fibrin sponge are inserted. On postoperative MRI it may be difficult to differentiate pathological from "normal" findings caused by routine manipulations. METHOD: In this study 14 patients free of symptoms after anterior discectomy with methacrylate-implant were examined clinically and a MRI was performed on the 7th day after surgery and again after a 6 month follow-up. All patients had an uneventful recovery and no signs of inflammation after surgery. FINDINGS: Independent of the underlying pathology (e.g. soft or hard disc) 73% of the patients had a signal reduction within the vertebral bodies adjacent to the operated disc on T1-weighted spin-echo images on the 7th postoperative day. Signal intensities were normal after 6 months in all patients. Remarkable metal artifacts were present in one patient only. The methacrylate-implant could be identified as a hypo-intense structure on all sequences at any time without artifacts. In 80% of the cases a hyperintensity was found on T2-weighted images between the methacrylate-implant and the dura on the 7th postoperative day. A protrusion of the posterior ligament was present at the level of the operated disc on day 7 after surgery, which had resolved completely 6 months later. This may mimic residual disc tissue or osteophytes early after surgery. INTERPRETATION: It is very important to know this "normal" postoperative appearance of the cervical spine in order to avoid misinterpretations.

Destruction of the glenoid joint fossa by a tenosynovial giant-cell tumour of the skull base: a case report.

A 63-year-old man is presented in whom a tenosynovial giant-cell tumour had destroyed the temporomandibular joint fossa and expanded intracranially. The lesion was not diagnosed for a period of at least two years. Treatment included wide resection including the surrounding bone, dura and condyle.

[Pigmented villonodular synovitis of the temporomandibular joint with invasion of middle cranial fossa]. / Pigmentierte villonoduläre Synovitis des Kiefergelenks mit Einbruch in die mittlere Schädelgrube.

A 63-year-old man is presented in whom a tenosynovail giant-cell tumor destroyed the right temporomandibular joint and fossa and showed extensive intracranial growth. Because of uncharacteristic complaints, a symptomatic treatment was performed elsewhere. The lesion was finally resected under endotracheal anesthesia. After 20 months free of recurrence the patient's outcome is very satisfying. Differential diagnosis and therapy are discussed.

[Delayed lumbar epidural hematoma. Discussion of the risk factors: hypertension, anticoagulation and spinal anesthesia]. / Mehrzeitiges lumbales epidurales Hämatom. Diskussion der begünstigenden Faktoren Hypertonie, Antikoagulation und Spinalanästhesie.

This case report deals with the very rare complication of an intraspinal haematoma: a 70 year old male underwent anticoagulation because of supraventricular dysrhythmias followed by two transient ischaemic attacks. He accidentally received an intramuscular injection for tetanus prophylaxis and developed a deep intramuscular haematoma, which was operated upon, after normalisation of coagulation parameters, under spinal anaesthesia. No primary complication was noted. Heparin therapy was started perioperatively, on the day of the operation. Sixteen days postoperatively, the patient resumed oral anticoagulation; 3 months later he developed a progressive cauda-equina-syndrome due to an epidural haematoma at the level of L2 to L4. This could be diagnosed by magnetic resonance imaging, but not by computed tomography. Acute surgical decompression was performed. The haematoma showed various ages as suspected by the intraoperative morphology and proven by histological examination. The neurological findings improved, and 6 months after rehabilitation only slight neurological deficits remained. Hypertension, anticoagulants, and spinal anaesthesia are discussed as risk factors for this complication.

Operative approach due to results of functional magnetic resonance imaging in central brain tumors.

Since 1995 we have been investigating the localization of the cortical motor strip by functional magnetic resonance imaging (fMRI) in central brain tumor cases. Forty patients have been operated on using these data for preoperative planning. Intraoperative sensory evoked potentials (SEP) and cortical motor evoked potential (performed in 18 patients) showed a good correlation with fMRI data with the exception of two cases. Only 12.5% of cases were permanently worsened as a result of increasing postoperative pareses.

MRI-guided endoscopy in the brain: a feasability study.

For neuronavigation in neuroendoscopy conventional navigation systems cannot exclude tissue movements caused by loss of cerebrospinal fluid (CSF). Open MRI can serve as a real-time navigation system if special conditions of endoscopic instruments and equipment are followed. We adapted an endoscopic system to the MRI and installed a miniaturized laser guidance system to project the central transaxial and coronal planes onto the phantom. A human cadaveric model was examined with a flexible microendoscope marked with a titanium wire inside the open magnet. The procedures were guided by gradient echo sequences refreshing the image every 4.5 seconds to control position of the endoscope. Endoscopic and corresponding MRI-findings are presented. Results and technical conditions are discussed.

[Fatal outcome of a cervical nerve block]. / Tödlicher Verlauf einer cervikalen Nervenblockade.

A patient with brachialgia was admitted to a surgical clinic and a cervical nerve block was performed under fluoroscopic guidance. Acute severe cervical pain prevented completion of the procedure. On the following day the patient developed incomplete paralysis of both legs and arms and was transferred to a neurosurgical department for further diagnosis and therapy. The CT scan showed a space-occupying cervical intraspinal haematoma, which was removed immediately as far as possible by a dorsal approach. Postoperatively little improvement of neurologic function was noticed, and 11 days after the event the patient died from a massive pulmonary embolism despite intense resuscitation efforts.

[Percutaneous ultrasound-assisted tumor cyst puncture of a recurrent intracerebral brain tumor]. / Perkutane ultraschallgesteuerte Tumorzystenpunktion eines intrazerebralen Hirntumorrezidivs.

The beneficial effects obtained by using transcutaneous ultrasound-guidance for brain puncture will be shown by a case report of a patient with a tumor-cyst after operation for a recurrent of an astrocytoma. In total this method was performed in 18 patients with high effectiveness and without any complications.

PMN granulocyte elastase--an early indicator of postoperative spondylodiscitis?

The diagnosis of spondylodiscitis after lumbar disc surgery has been based so far on clinical abnormalities, non-specific changes in chemical laboratory parameters [erythrocyte sedimentation rate (ESR), C-reactive protein (CRP)] and radiological examinations such as MRI. Such techniques do not enable any clear diagnosis to be made before the 3rd postoperative week. The PMN elastase released from stimulated polymorphonuclear granulocytes has been proved to be a good laboratory parameter by which it is possible to prognosticate bacterial and abacterial organ complications in surgical patients with a high degree of probability. Under investigation were 12 patients with spondylodiscitis out of 1162 operations on herniated lumbar discs. PMN elastase was determined on the 7th postoperative day. In patients with spondylodiscitis and a mean value of 110.5 micrograms/l, the elastase was on average higher by a factor of 2.6 as compared to 88 randomly selected control patients. Since spondylodiscitis is a rare complication, this results in a positive value of only 7%, which does not allow a reliable diagnosis of spondylodiscitis by the elastase assay. But because the negative predictive value is 100%, it is possible to exclude a postoperative spondylodiscitis already on the 7th postoperative day, if the elastase value is normal.

[Intraoperative complications in lumbar intervertebral disk operations. Cooperative study of the spinal study group of the German Society of Neurosurgery]. / Intraoperative Komplikationen während lumbaler Bandscheibenoperationen. Kooperative Studie der Arbeitsgemeinschaft Wirbelsäule der Deutschen Gesellschaft für Neurochirurgie.

The workshop "Wirbelsüle" of the German Society of Neurological Surgery started a cooperative study about the incidence of intraoperative complications during lumbar disc surgery. The results relate a number of 68,329 operations, among them a percentage of 2.560% of total complications, including 0.0132% with fatal ending. The highest number of complications related to the lesions of spinal structures (3.202%). Abdominal bleeding by vascular lesions occurred in 0.045%., the incidence of abdominal organ injury was reported in single cases (0.003%).

[Injuries to retroperitoneal arteries in lumbar intervertebral disk surgery]. / Verletzungen retroperitonealer Arterien bei lumbalen Bandscheibenoperationen.

Retroperitoneal bleeding as a rarely occurring but life-threatening event after lumbar disc surgery is being presented in three cases. Discussion includes necessary steps in establishing the diagnosis for adequate therapy by referring to clinical features with their anatomical background.

Computer tomographic assessment of perifocal edema surrounding tumors of the cerebral cortex.

It is well known, that intracranial tumors can induce peritumoral edema of variable extension. Some authors describe a dependency between malignancy of tumor and size of perifocal edema. It is generally accepted that metastases induce the largest perifocal edema. This study investigates the relationship between the volume of the perifocal edema and its distance from the surface of the cortex.

[Etiology of the recurrence of lumbar intervertebral disk displacement]. / Atiologie lumbaler Bandscheibenvorfallrezidive.

In a review for reasons of 100 disc prolapses reoperations we found in 62% a recurrence of disc prolapse at the same level, in 24% a recurrence at a different level, whereas in 14% we found that the nerve route was closely connected. We reoperated 44% in the first two years and 69% in the first five years. The time between the operations was prolonged if there was a short period of time for relief of pain after operation and a long period of preoperative symptoms. The variables of risk of a disk prolapse recurrence are recorded in a risk score, in which 64% of the patients belonged retrospectively to a risk group. The correlation between operation interval and score points showed that patients with short interval had high score ratings.

[Gorham syndrome. Presentation of a case]. / Das Gorham-Syndrom. Aufarbeitung einer Kasuistik.

A case report on a female patient who developed a squamofrontal tumour on the right side without any neurological deficit. After extirpation the histological diagnosis was "disappearing bone" disease. This disease pattern is rarely described in literature and has several synonyms. The histological appearance is described.