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Biomedical subjects

M Schulder

Publications and source records attributed to M Schulder.

At least 37 records · Page 2Linked to original sources
PubMed1999

Microsurgical removal of a vestibular schwannoma after stereotactic radiosurgery: surgical and pathologic findings.

OBJECTIVE: The objective of this study was to provide objective evidence of the enhanced difficulty of preserving the facial nerve in patients who need microsurgery after failed stereotactic radiosurgery (SRS) of vestibular schwannoma. STUDY DESIGN: This study was a retrospective case review. SETTING: A tertiary care referral center was the setting for the study. PATIENTS: The authors present a case of a young woman with a vestibular schwannoma that enlarged 2 years after treatment with SRS. INTERVENTION: Microsurgery via the translabyrinthine approach was used. RESULTS: At surgery, extensive scarring between the facial nerve and tumor capsule was seen, and the nerve could not be identified at all beyond several millimeters proximal to the porus acusticus. Adhesions of the tumor to the ninth and tenth cranial nerves, the brain stem, and the anterior inferior cerebellar artery were also markedly increased. Histologic examination confirmed fibrotic adhesions surrounding the facial nerve. CONCLUSIONS: The unusual degree of fibrosis, scarring, and adhesions of the tumor to the surrounding structures after SRS made microsurgical removal of the tumor difficult and preservation of the facial nerve impossible.

Adult↗
PubMed1998

Hemorrhagic chondroid chordoma mimicking pituitary apoplexy.

We describe a hemorrhagic chondroid chordoma involving the sella turcica with suprasellar extension. The CT and MRI appearances mimiked a hemorrhagic pituitary adenoma. Chondroid chordoma is a variant composed of elements of both chordoma and cartilaginous tissue. An uncommon bone neoplasm, located almost exclusively in the spheno-occipital region, it is usually not considered in the differential diagnosis of a tumor with acute hemorrhage in the sellar region. We discuss the clinical and radiological characteristics which may allow one to differentiate chondroid chordoma from other tumors of this area.

Aged↗
PubMed1998

Functional image-guided surgery of intracranial tumors located in or near the sensorimotor cortex.

OBJECT: The purpose of this study was to evaluate the efficacy of noninvasive preoperative functional imaging data used in an interactive fashion in the operating room. The authors describe a method of registering preoperative functional magnetic resonance (fMR) imaging localization of sensorimotor cortex with a frameless stereotactic surgical navigation device. METHODS: The day before surgery, patients underwent blood oxygen level-dependent fMR imaging while performing a finger-tapping motor paradigm. Immediately afterward an anatomical stereotactic MR image was acquired. Raw fMR imaging data were analyzed offline at a separate workstation, and the resulting functional maps were registered to a high-resolution anatomical scan. The fused functional-anatomical images were then downloaded onto a surgical navigation computer via an ethernet connection. At surgery, the brain was exposed in the standard fashion, and the sensorimotor cortex was identified by direct cortical stimulation, the use of somatosensory evoked potentials, or both. This localization was then compared with that predicted by the registered fMR study. Thirteen procedures were performed in 12 patients. The mean registration error was 2.2 mm. The predicted location of motor and/or sensory cortex matched that found on intraoperative mapping in all 12 patients tested. Maximal tumor resection was accomplished in each case and no new permanent neurological deficits resulted. CONCLUSIONS: Compared with conventional brain mapping techniques, fMR image-guided surgery may allow for smaller brain exposures, localization of the language cortex with the patient under general anesthesia, and the mapping of multiple functional sites. The scanning equipment used in this method may be more readily available than for other functional imaging techniques such as positron emission tomography or magnetoencephalography.

Adult↗
PubMed1997

Neurosarcoid infiltration of the ventricular catheter causing shunt failure: a case report.

BACKGROUND: Neurosarcoid is known to develop in 5% of patients with sarcoidosis. A frequent manifestation of this condition is hydrocephalus, which will often require treatment with a ventricular shunt. METHODS: Presented here is the case of a patient whose initial manifestation of neurosarcoidosis was hydrocephalus, and who then represented with multiple shunt failures. RESULTS: On two revisions, the proximal catheter, after removal, was found to be occluded with noncaseating granulomatous material that had infiltrated the shunt lumen. CONCLUSIONS: Although shunts may become occluded by inspissated proteinaceous or cellular debris, the occlusion of a shunt catheter by the ingrowth of the noncaseating granulomatous material of neurosarcoid has not been described before. This patient's course, the histopathologic findings, and neurosarcoidosis in general are discussed here.

Adult↗
PubMed1997

Permanent low-activity iodine-125 implants for cerebral metastases.

Beginning in 1987, selected patients with metastatic brain tumors were treated with permanent implants of low-activity radioactive iodine-125(125I) seeds. These patients underwent craniotomy, gross total resection of the metastatic lesion, and placement of the seeds. In general, criteria for treatment included the presence of a recurrent tumor with a volume too large to permit radiosurgery, and a Karnofsky Performance Score of 70 or higher. Thirteen patients underwent 14 implant procedures; all received external whole-brain radiotherapy. Implant dose ranged from 43 Gy to 132 Gy, with a mean of 83 Gy. Survival after implantation ranged from 2 weeks to almost 9 years, with a median of 9 months. Clinical and radiographic local control was obtained in 9 patients. Two patients died of acute, postoperative complications within a month of implantation, so no information regarding tumor control is available for them. Late complications included a bone flap infection in one patient and a CSF leak in another; both were treated without further sequelae. These results demonstrate that permanent 125I implants can results in good survival and quality of life, and occasionally can yield long-term survival. Potentially, it is a cost-effective treatment in that a separate procedure for stereotactic implantation or radiosurgery is not needed, as is the case with the use of temporary high-activity seeds. The permanent implantation itself adds less than 10 minutes to the craniotomy, and the risk of symptomatic radiation necrosis is low. We recommend consideration of this procedure in patients harboring large, recurrent metastatic tumors that require further surgery.

Adult↗
PubMed1997

Functional MRI-guided surgery of intracranial tumors.

We describe a technique of registering functional magnetic resonance image (fMRI) data sets with the anatomical images used for intraoperative navigation. Three patients with supratentorial tumors were studied, 2 with astrocytomas and 1 with a meningioma. The day before surgery, a functional blood-oxygen-level-dependent MR scan was done. During the same imaging session, an anatomic stereotactic MR scan was performed. The raw data were reconstructed off line on a workstation, and the fMR maps were then registered to the anatomic studies using image header information. Fused images were then transferred to the navigational workstation over an Ethernet connection. At surgery, brain exposure was performed in a standard manner. In each case, the registered scans accurately localized the motor and/or sensory cortex. No new permanent neurological deficits resulted from surgery. The potential advantages of fMRI-guided surgery include: (1) smaller brain exposures; (2) localization of language cortex under general anesthesia; (3) mapping of multiple functional sites, with decreased time and increased case of surgery.

Adult↗
PubMed1996

The influence of Harvey Cushing on neuroradiologic therapy.

Harvey Cushing was largely responsible for the establishment of neurosurgery as a separate discipline. He demonstrated how careful attention to technique could make surgery acceptably safe, established classifications and clinical-pathologic correlations of a wide variety of tumors, and trained dozens of future neurosurgical department heads. Less well known, however, is Cushing's contribution to the early clinical use of radiation therapy for a variety of intracranial disorders. With the aid of his meticulous clinical follow-up, large case volume, and willingness to try new treatment methods, he demonstrated the utility of therapeutic radiation in patients with pituitary tumor, medulloblastoma, and arteriovenous malformation. His less impressive results with the irradiation of patients with glioma are also worthy of note and include trials of brachytherapy. Neurosurgeons and radiation oncologists exploring new methods of delivering therapeutic radiation to the central nervous system should be aware of the lessons learned from Cushing's experience.

Adenoma↗
PubMed1996

Historical vignette: The radium bomb: Harvey Cushing and the interstitial irradiation of gliomas.

Harvey Cushing performed over 2000 operations on patients with brain tumors, including 832 for gliomas. He implanted radioactive radium needles, known as a "radium bomb," in a small number of these patients. He was not impressed with the results and did not pursue this method of treatment in a serious way. The authors present here Cushing's little-known experience with brachytherapy and discuss the reasons for his lack of interest in this technique, despite his advocacy of radiotherapy for certain lesions. An interesting perspective is offered for contemporary neurosurgeons involved in the treatment of brain tumors with cranial irradiation.

Brachytherapy↗
PubMed1996

Endoscopic closure of the eustachian tube for repair of cerebrospinal fluid leak.

Techniques to repair cerebrospinal fluid (CSF) leak through the eustachian tube (ET) include temporary or permanent CSF diversion; middle fossa craniotomy and packing of the ET from above; and packing of the ET from behind, through the middle ear. We report a case of endoscopic closure of the ET in the nasopharynx (the front). A 26-year-old woman underwent a translabyrinthine removal of a 4.5-cm vestibular schwannoma. One year later, she developed CSF rhinorrhea and meningitis. Attempts at control of this leak included traditional approaches mentioned previously (shunting, middle fossa, middle ear packing). The leak recurred 2-3 months after each procedure. An endoscope was used transnasally to expose the ET orifice, which was incised, inverted, and cauterized. She has remained free of leak for 1 year. Our success in this difficult case suggests that this is a useful procedure for treatment of CSF rhinorrhea originating in the posterior fossa. Greater experience is needed to verify its long-term effectiveness and utility as a primary procedure for the treatment of CSF rhinorrhea.

Adult↗
PubMed1995

Central nervous system tuberculosis: medical management and surgical indications.

BACKGROUND: An increase in the incidence of tuberculosis in industrialized nations has prompted a need for earlier diagnosis, treatment, and isolation of disease. An associated rise in the number of patients with central nervous system tuberculosis (CNS TB) has forced neurosurgical services to reevaluate the indications for operative intervention. METHODS: Seventeen cases of CNS TB were found in a retrospective review of all cases managed on the neurosurgical service between 1989 and 1994. These cases included eight with tuberculous meningitis, seven cases of supratentorial tuberculomas, and two cases of infratentorial tuberculomas. RESULTS: Major permanent neurologic morbidity was seen in one case (6%). Five patients (29.4%) died of complications associated with their primary disease. Eleven patients (64.6%) had excellent outcomes. All patients in the latter group completed an 18-month course of antituberculous therapy. Cerebrospinal fluid shunts were necessary in three cases and emergent craniotomy was performed in three cases. Only four cases had human immunodeficiency virus (HIV) coinfection. CONCLUSION: The neurosurgeon's role in the management of CNS TB has once again become more evident. In the present series it is unclear as to whether this is due to multiple drug-resistant strains of Mycobacterium tuberculosis or HIV coinfection. It is clear, however, that vigilance over patient compliance and serial neurologic evaluation will determine the need for operative intervention.

Adult↗
PubMed1995

Halifax clamps: efficacy and complications in posterior cervical stabilization.

BACKGROUND: Trauma, neoplasia, rheumatoid arthritis, Down's syndrome, and inflammatory conditions are well-known causes of spinal instability. The Halifax clamp is a method of posterior cervical stabilization that is attached to the adjoining laminae and tightened until no movement between involved vertebrae is possible. Our experience with cases that have utilized Halifax interlaminar clamps, their results and complications are presented. METHODS: We conducted a retrospective review of patients with spinal instability in whom Halifax interlaminar clamps were utilized for posterior spinal stabilization. RESULTS: Over a 5-year period, 38 patients in our institution underwent posterior stabilization of the cervical spine utilizing the Halifax interlaminar clamp. The patients represent a mix of motor vehicle- and sports-related traumas, rheumatoid subluxation, and a single cancer patient. Average follow-up has been 29 months (range 3 to 36 months). Thirty (78.9%) patients have had good results (i.e., stable fusion and regression of symptoms) and no complications. Three patients from our institution, and a fourth patient referred to us postoperatively, developed complications related to the Halifax clamps. Four patients died from unrelated causes. CONCLUSIONS: Halifax interlaminar clamps are a safe and effective method for posterior stabilization of various causes of cervical spinal instability.

Adolescent↗
PubMed1994

Cerebral tuberculosis with expansion into brainstem tuberculoma. Report of two cases.

There are only scattered case reports of intracranial tuberculosis in industrialized nations; brainstem tuberculoma is even more unusual, accounting for 2.5% to 8% of all intracranial tuberculoma. In developing nations, however, central nervous system tuberculosis (CNS-TB) is not rare and intracranial tuberculoma may account for 5% to 30% of all intracranial masses. The authors present two cases of CNS-TB with expansion to brainstem tuberculoma in patients who were undergoing treatment and had no known prior exposure to Mycobacterium tuberculosis.

Adult↗
PubMed1993

Nonsurgical treatment of compound depressed skull fractures.

Classical treatment of compound depressed skull fractures includes debridement and closure of all scalp wounds to minimize the risk of delayed intracranial infection. In selected situations, a nonsurgical approach may prove to be equally safe. Over a 33-month period, we evaluated 1075 patients for head trauma. There were 63 patients with non-missile, compound depressed skull fractures (9 of these 63 patients have been excluded for deaths that occurred within 4 days of admission). Patients with significant intracranial hematomas or dural violations over the convexity of the brain underwent formal surgical therapy. Surgical therapy was performed on 28 patients (52%; age 33 +/- 3 years; ISS 24 +/- 2) and it consisted of craniotomy with debridement, elevation of depressed fragments, repair of dural tears, and evacuation of hematomas. Nonsurgical treatment was used if there was no evidence of violation of the dura mater and of significant intracranial hematoma. If the following criteria were satisfied, then the nonsurgical approach was employed: no evidence of exposed brain or a cerebrospinal fluid leak, no pneumocephalus related to the fracture, no depressed fragments of bone more than 1 cm below the inner table of the skull, and no gross wound contamination. Nonsurgical therapy was used on 26 patients (48%; age 34 +/- 3 years; ISS 19 +/- 2) and it consisted of wound irrigation, debridement, and closure. In all 54 patients of both subsets of patients, intravenous antibiotics were administered for 5 to 7 days. After two additional days of observation, off antibiotics, the patients were discharged. There were no infectious complications related to the central nervous system.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Management of traumatic optic neuropathy--a study of 23 patients.

Twenty three patients with traumatic optic neuropathy were managed by medical and surgical treatment as follows. High dose intravenous steroids were initiated in all patients. If visions did not improve significantly after 24 to 48 hours decompression of an optic nerve sheath haematoma by medial orbitotomy and neurosurgical decompression of the optic canal were considered based on computed tomographic scan findings. Nine of 16 patients who received steroids only showed significant improvement. One of three showed improvement on optic nerve decompression after steroid failure; three or four showed improvement on optic nerve decompression after steroid failure; three or four showed improvement with combined optic nerve sheath decompression by the medial orbitotomy and decompression of the optic canal by frontal craniotomy. A lucid interval of vision after injury and an enlarged optic nerve sheath were associated with an improved prognosis. Five of the 23 patients had a lucid interval and all five had a final improved vision, while only five of 18 patients without a lucid interval improved. Similarly seven of the nine with an enlarged optic nerve sheath showed improvement while only three of 10 patients (three bilateral cases) who presented with no light perception improved with medical and surgical treatment. While a prospective controlled study of the management of traumatic optic neuropathy is necessary this preliminary study suggests that treatment of traumatic optic nerve sheath haematoma by optic nerve sheath decompression should be considered in selected patients.

Adolescent↗