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H Fankhauser

Publications and source records attributed to H Fankhauser.

At least 19 recordsLinked to original sources
PubMed1992

Osseous metastases from a benign intraventricular meningioma. Case report.

The authors report a case of a 6 month-old male presenting with increasing head circumference and a large benign intraventricular meningioma which was grossly removed at the initial surgery. Twenty-four months later, the patient returned with subcutaneous and osseous metastatic lesions at the site of the previous craniotomy, revealing the same histology as the original tumour. The presentation, pathology and management of this unique case are discussed.

Cerebral Ventricle Neoplasms↗
PubMed1992

Microsurgical anatomy and operative technique for extreme lateral lumbar disc herniations.

The anatomy of the lateral aspect of the lumbar spine and our lateral microsurgical technique for extreme lateral lumbar disc herniations (ELLDH) is described. This study was based on the microdissection of 4 cadavers, on the morphometric evaluation of these as well as 6 dried cadaver spines and 8 lumbar CT scans, and on the use of this technique on over 200 cases. Level dependent changes in the posterior arch cause a shift of the disc space distally relative to the facet joint, an increasing amount of bone to overlie the intervertebral foramen, and a decreasing amount of working space within the exposure in the caudal direction. Therefore, more bone removal from the lateral aspect of the pars interarticularis and supero-lateral aspect of the facet joint is required in the lower lumbar spine. When the exposed ligamentum flavum is resected, the dorsal root ganglion is seen and access to the herniation and disc space is achieved. Level dependent changes in the pedicles and transverse processes lead to an alteration in the course and relationships of the nerves, thereby influencing the pathophysiology of and surgical technique for the ELLDH. The operative target is the lateral aspect of the pars interarticularis and not the intertransverse space as has been previously described. Our techniques allows for the early identification of the nerve with minimal risks of injury to it, to the adjacent vessels and to the structural integrity of the facet joint and pars interarticularis.

Humans↗
PubMed1992

Isolation and characterization of regulatory mutants from Schizosaccharomyces pombe involved in thiamine-regulated gene expression.

Mutants from Schizosaccharomyces pombe deficient in the regulation of thiamine-repressible acid phosphatase have been isolated. Mutants expressing derepressed levels of the enzyme in the presence and absence of thiamine map in three genes, tnr1, tnr2 and tnr3. mRNA levels of the pho4 gene (coding for thiamine repressible acid phosphatase) and another thiamine-regulatable gene, thi3 (coding for a thiamine biosynthetic enzyme and corresponding to nmt1) are constitutively synthesized in the mutants. The mutants also exhibit constitutive thiamine transport which is thiamine repressible in wild type. The tnr3 mutants reveal a 10-20-fold higher intracellular thiamine level than tnr1 and tnr2 mutants and wild type. Mutants expressing repressed levels of thiamine-repressible acid phosphatase map in gene thi1. No or little amounts of pho4- and nmt1-specific mRNA can be detected. These mutants are impaired in thiamine uptake and are thiamine auxotrophic due to the inability to synthesize the thiazole moiety of the thiamine molecule. All tested tnr and thi1 alleles are recessive, and thi1 mutations are epistatic over tnr mutations. We assume that the thi1 and tnr genes are involved in thiamine-mediated transcription control.

Acid Phosphatase↗
PubMed1992

A software tool to assist placement of multiple parallel brachytherapy sources using the Brown-Roberts-Wells stereotactic system.

The authors present a simple software written in Turbo Pascal which allows placement of multiple parallel sources for interstitial brachytherapy using the Brown-Roberts-Wells CT stereotactic system. The user can choose any direction in space, independently from the CT plane, and any number of linear sources arranged on one or more hypothetical cylinders of variable radius. The sources can be rotated on the cylinder in order to avoid critical structures. This small program runs on any IBM compatible computer.

Brachytherapy↗
PubMed1991

Cyst of the ligamentum flavum: report of six cases.

Six cases of cyst of the ligamentum flavum with compression of a lumbar nerve root are reported. All patients exhibited recurrent back pain and sciatica. Investigation included computed tomography, myelography, or both. The correct diagnosis was reached before operation in only half the patients. High-resolution computed tomography performed in the four last patients outlined the cystic lesion with its low-density center. Surgical excision was performed in all patients. Microscopic examination showed a dense fibrous cyst arising from the ligamentum flavum. The lumen contained myxoid or necrotic material, but no epithelial lining. Cysts of the ligamentum flavum must be considered in the differential diagnosis of causes of sciatica. A firm radiological diagnosis may, at present, still require myelography combined with high-resolution computed tomography. Differentiation from synovial or ganglion cysts of the spine is discussed.

Aged↗
PubMed1991

Computed tomography of the postoperative intervertebral disc and lumbar spinal canal: serial long-term investigation in 19 patients after successful operation for lumbar disc herniation.

The first part of this work, published in 1988, included 25 patients who had computed tomographic (CT) scans without contrast enhancement and plain x-rays of the lumbar spine before, 1 week after, and 6 to 7 weeks after a successful operation for lumbar disc herniation. The present study extends the follow-up period to 3 years in 19 of the 25 original patients. Clinical examinations, lateral plain x-rays, and CT scans without contrast enhancement of the operated disc were repeated. The results indicate a decrease or even a disappearance of the hyperdense extradural material thought to represent fibrosis. An image suggestive of persistent disc herniation was still present in 5 of 8 patients with this finding on early postoperative CT scans. Persistent intradiscal gas was seen in nearly half of the patients. Total normalization of the posterior extraspinal structures was the rule. There was no correlation between CT appearance and residual complaints of the patients. CT scans without contrast enhancement may be sufficient to guide the surgeon in postoperative patients with massive signs and symptoms of recurrent root compression in whom a second operation is indicated on clinical grounds. In all other cases, myelography followed by CT scans is considered appropriate to investigate failed back surgery syndrome.

Adipose Tissue↗
PubMed1991

Arteriovenous malformation in meningothelial meningioma: case report.

An unusual association of a meningioma and an arteriovenous malformation is reported. A 68-year-old man developed left homonymous hemianopsia, left hemiparesis, and gaze palsy. Magnetic resonance imaging showed a right occipital mass lesion containing multiple signal-void areas with tubular and honeycomb appearance, suggesting a marked vascular component. An angiogram showed abnormal vasculature in the mass supplied by the posterior cerebral artery and a dural arteriovenous malformation on the tentorium. Neuropathological examination after total removal of the mass revealed a meningothelial meningioma including major portions of an arteriovenous malformation that extended from the dura and leptomeninges, through the meningioma, and into the occipital lobe, where the tumor was located.

Aged↗
PubMed1990

Development of a new microsurgical robot for stereotactic neurosurgery.

The robot technology was introduced into a new stereotactic neurosurgery system for applications to biopsy, blind surgery, and functional neurosurgery. The authors have developed a newly designed prototype microsurgical robot, designed to allow a biopsy needle to reach the target such as a cerebral tumor within a brain automatically on the basis of the X, Y, and Z coordinates obtained by CT scanner. This robot is so small that it can be driven in a CT scanner gantry. It consists mainly of the link mechanism and the insertion mechanism. We constructed the link mechanism and investigated its working space.

Biopsy, Needle↗
PubMed1990

Configuration of a robot dedicated to stereotactic surgery.

The design of a robot for functional stereotactic surgery which is under construction in our laboratory is described. The main features include operation inside the computed tomographic (CT) scanner, the possibility of intraoperative CT scanning and complete handling of the stereotactic probes by the robot.

Brain Diseases↗
PubMed1989

Unusual presentation of thoracic disc herniation.

A 24-year-old patient with thoracic disc herniation mimicking lumbar disc disease is reported. While getting out of his car the patient suffered an acute onset of lumbar pain radiating down to the buttock and vaguely into the abdomen on the right. Myelography and computed tomography demonstrated a centrolateral noncalcified disc herniation at T10-11, in close relation to a Schmorl's node. The different clinical presentations of thoracic disc herniation are discussed.

Adult↗
PubMed1988

[Normal-pressure hydrocephalus in adults. Analysis of results and complications following ventriculo-cardiac derivation].

The results of ventriculo-atrial shunting have been analyzed in 37 patients with normal pressure hydrocephalus. The nature and severity of the symptoms and their progression in time, together with the results of computed tomography and clinical response to CSF withdrawal by lumbar puncture, were compared with the outcome after shunting, in order to define reliable prognostic criteria. In the long term, 43% of the patients improved and 30% died. The complication rate was 22%, including primarily subdural hematoma and shunt malfunction. Amongst the symptoms, ataxia responded best to shunting. Clinical improvement after subtraction of lumbar CSF, and demonstration by computed tomography of ventricular dilation with a hypodense area around the frontal horns in the absence of cortical atrophy, were associated with a favorable outcome.

Aged↗
PubMed1988

Computed tomography of the postoperative intervertebral disc and lumbar spinal canal: investigation of twenty-five patients after successful operation for lumbar disc herniation.

Twenty-five patients with good outcome after operation for lumbar disc herniation underwent unenhanced computed tomography (CT) and plain radiography of the lumbar spine before, 5 to 7 days after, and 6 to 7 weeks after the operation to define the radiological features of the postoperative disc and spinal canal. After operation, the center of the disc appears hypodense. The anterior and lateral borders remain sharply delimited, but in 44% of the cases the posterior border shows an image suggesting the persistence of disc herniation. In 84% of the cases, there are major changes in the spinal canal with complete occlusion of the extradural space on the operated side by a heterogeneous material the attenuation value of which ranged between those of cerebrospinal fluid and disc. The outline of the dural sac and of the nerve root is lost. This aspect did not significantly change between the 1st and the 6th postoperative week, except for the disappearance of any air within the canal and a slight movement on the dural sac toward the operated side. From these major radiological modifications found in asymptomatic postoperative patients, it is concluded that positive CT in patients with the failed back surgery syndrome has limited value. Myelography is preferred as the primary neuroradiological investigation.

Adult↗
PubMed1988

[The herniated disk].

Explore the source record for details and available documents.

Combined Modality Therapy↗
PubMed1987

Extreme lateral lumbar disc herniation.

Extreme lateral lumbar disc herniation (ELLDH) occurring into and/or outside the intervertebral foramen was encountered in 95 cases amongst 1600 operations for herniated lumbar disc (6%): 43% occurred at L5-S1, 38% at L4-5, 18% at L3-4, and 1% at L2-3. The incidence amongst all herniations at one particular level was 6% at L5-S1, 4% at L4-5, and 18% at L3-4. The clinical presentation varied according to the level of extreme lateral disc herniation, but was not different from the presentation of a classical paramedian herniation occurring one level above. Forty-three patients were investigated with computed tomography (CT) only, 2 with myelography only, and 50 with both. CT always clearly demonstrated the pathology, but some cases are presented to illustrate the differential diagnosis. Myelography was normal in 13 cases; in 27 cases it showed a typical shortening and enlargement of the nerve root sheath which enters the affected intervertebral foramen. At operation, a total facetectomy was performed in 52 patients, a partial facetectomy in 34, and a lateral approach to the intervertebral foramen in 9. The lateral approaches, either paramuscular with retraction of the paraspinal muscles from the midline, or transmuscular by splitting of the paraspinal muscles, are described and illustrated in detail.

Adult↗
PubMed1986

Computed tomography in spinal hemangioma with cord compression. Report of two cases.

Two teenagers with spinal cord compression due to a thoracic vertebral hemangioma are presented. Myelography showed a complete block in both patients. Selective intercostal arteriography was normal or non-conclusive. Only computed tomography (CT) gave precise information about the extent and nature of the compressive lesion. In the first case it showed angiomatous involvement of the body and all parts of the neural arch of T4, and a posterior epidural ossified angiomatous mass. In the second case it showed angiomatous involvement of the vertebral body and an anterior extradural soft tissue mass; this latter was considered to represent a resolving extradural hematoma. CT, preferably performed after intrathecal contrast injection, is the diagnostic procedure of choice for spinal hemangioma with cord involvement.

Adolescent↗