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Meic H Schmidt

Publications and source records attributed to Meic H Schmidt.

At least 37 records · Page 2Linked to original sources
PubMed2004

Clinical trials and evidence-based medicine for metastatic spine disease.

Treatment of metastatic epidural spinal disease has undergone significant changes over the last 20 years. No longer is indiscriminate decompressive laminectomy offered as the only surgical treatment. It carries all the risks associated with an invasive procedure and offers the patient little benefit unless it is used to remove disease isolated to the posterior elements. The existing literature suggests that surgery that frees the spinal cord at the site of compression in addition to reconstructing and stabilizing the spinal column is more effective at preserving and regaining neural function, notably ambulatory function and sphincter function, than conventional radiotherapy. It is also highly effective in relieving pain. The preliminary results ofa recent RCT provide the first class I evidence to support a reversal in the current philosophy of primary treatment for many patients with meta-static disease. Conventional radiotherapy has a clearly defined role as adjuvant therapy and as primary therapy in those who are unable to tolerate or benefit significantly from surgery. The role of nonconventional radiation therapy, such as IMRT and SRS, remains to be elucidated.

Clinical Trials as Topic↗
PubMed2004

Central neurocytoma: a review.

Central neurocytomas are rare intraventricular neoplasms of the central nervous system, compromising 0.25-0.5% of brain tumors. The diagnosis and management of these tumors remains controversial since most clinical series are small. Typically, patients with central neurocytomas have a favorable prognosis, but in some cases the clinical course is more aggressive. Although histological features of anaplasia do not predict biologic behavior, proliferation markers including MIB-1 might be more useful in predicting relapse. The most important therapeutic modality is surgery, and a safe maximal resection confers the best long-term outcome. In cases of a subtotal resection,'standard external beam radiation can be added or radiation can be delayed until tumor progression occurs. Smaller residual tumor volumes or recurrences can be treated with more conformal radiation or focused radiosurgery. Re-operation for recurrence should be considered if the procedure can be safely performed. Chemotherapy may be useful for recurrent central neurocytomas that cannot be resected and have been radiated, although long-term responses have not been reported for chemotherapy. Overall, this paper reviews the findings of the larger studies and highlights some of the important case reports that contribute to the current management of central neurocytomas.

Brain Neoplasms↗
PubMed2004

Resolution of intracranial hypertension after elevation of depressed cranial fracture over the superior sagittal sinus: case report.

OBJECTIVE AND IMPORTANCE: It is common neurosurgical wisdom that depressed cranial fractures (DCFs) over the superior sagittal sinus (SSS) should not be elevated because of the risk of fatal venous hemorrhage. CLINICAL PRESENTATION: A 34-year-old man presented with severe headache and diplopia after a motor vehicle accident. Clinical examination demonstrated severe papilledema and bilateral abducens palsy. Imaging findings demonstrated a DCF over the posterior third of the SSS and absent flow distal to the fracture with dilated cortical venous drainage. INTERVENTION: Conservative treatment with acetazolamide only partially alleviated the patient's headache and diplopia. Definitive surgical treatment via elevation of the DCF was discussed and decided upon. Twelve days after injury, the patient underwent midline parieto-occipital craniotomy with successful elevation of the DCF off the posterior third of the SSS. Postoperative magnetic resonance venograms revealed restoration of patency in the SSS with reduced tortuosity of cortical veins. The patient's headache resolved, and his papilledema and diplopia resolved gradually. CONCLUSION: Elevation of DCF over the SSS can be attempted in cases in which favorable bone anatomy and the patient's clinical condition warrant. This may result in rapid and dramatic resolution of signs and symptoms of secondary intracranial hypertension.

Adult↗
PubMed2004

Surgical management of spinal metastases.

Metastatic spread to the spinal column is a growing problem in patients with cancer. It can cause a number of sequelae including pain, instability, and neurologic deficit. If left untreated, progressive myelopathy results in the loss of motor, sensory, and autonomic functions. Except in rare circumstances, treatment is palliative. Traditionally, conventional fractionated external beam radiotherapy has been the treatment of choice. "Surgery" for metastatic spinal disease was, and generally continues to be, equated with laminectomy by many physicians. However, there has been a remarkable evolution in surgical techniques over the last 20 years. Today, the goal of surgery is to achieve circumferential decompression of the neural elements while reconstructing and immediately stabilizing the spinal column. This has been made possible by the use of different surgical approaches and the exploitation of a burgeoning array of internal fixation devices. More recently, minimally invasive surgical techniques, such as endoscopy, kyphoplasty/vertebroplasty, and stereotactic radiosurgery, have been added to the surgeon's armamentarium. As the number of treatment options for metastatic spinal disease grows, it has become clear that effective implementation of treatment can only be achieved by a multidisciplinary approach. This will provide the surest means of maximizing the quality of the remainder of the patient's life.

Humans↗
PubMed2003

Treatment of metastatic spinal epidural disease: a review of the literature.

OBJECT: Spinal cord compression is one of the most dreaded complications of metastatic cancer. It can lead to a number of sequelae, including pain, spinal instability, neurological deficits, and a reduction in the patient's quality of life. Except in selected circumstances, treatment is palliative. Treatment options include surgery, radiation, and chemotherapy. The goal of this study was to summarize the existing data on the outcomes of various treatment methods for metastatic spinal epidural disease and to make appropriate recommendations for their use. METHODS: The authors used a search strategy that included an electronic database search, a manual search of journals, analysis of bibliographies in relevant review papers, and consultation with the senior author. There is good evidence, including Class I data, that steroid drugs constitute a beneficial adjunctive therapy in patients with myelopathy from epidural compression. Historically, conventional radiation therapy has been viewed as the first-line treatment because it has been shown to be as effective as a decompressive laminectomy, with a lower incidence of complications (Class II data). Nevertheless, in the last 20 years there has been remarkable progress in surgical techniques and technology. Currently, the goals of surgery are to achieve a circumferential decompression of the spinal cord, and to reconstruct and immediately stabilize the spinal column. Results in a large body of literature support the belief that surgery is better at retaining or regaining neurological function than radiation and that surgery is highly effective in relieving pain. Most of the data on the treatment of metastatic spinal disease are Class II or III, but the preliminary results of a well-designed, randomized controlled trial in which surgery is compared with standard radiation therapy represents the first Class I data. CONCLUSIONS: As the number of treatment options for metastatic spinal disease has grown, it has become clear that effective implementation of these treatments can only be achieved by a multidisciplinary approach.

Adrenal Cortex Hormones↗
PubMed2003

Lumbosacral ependymomas: a review of the management of intradural and extradural tumors.

OBJECT: The goal of this study was to review the management of intra- and extradural ependymomas. Spinal ependymomas most commonly occur as intramedullary tumors throughout the spinal axis. In the lumbosacral region, ependymomas are most commonly associated with the conus medullaris and cauda equina, but can also occur extradurally in the sacrum, presacral tissues, or subcutaneous tissues over the sacrum. These two tumor locations produce different management concerns. Intradural ependymomas, especially those in the lumbosacral region, are now recognized for their potential to spread throughout the central nervous system (CNS), whereas extradural tumors elicit more concern for their association with extraneural metastases. METHODS: The authors have reviewed the literature regarding both of these distinct tumors and have summarized recommendations for the management of intra- and extradural lumbosacral ependymomas. For both tumors, it appears that gross-total resection is the treatment of choice when feasible. The role of radiation therapy has not been adequately studied for either tumor location, but most clinicians use this modality in patients with subtotal resection of intradural ependymomas, local recurrence, or CNS dissemination. Data supporting the use of radiation therapy for extradural ependymomas are lacking. There does not appear to be a significant role for chemotherapy in either tumor location. CONCLUSIONS: Despite the risk for local recurrence and CNS dissemination, the prognosis for intradural lumbosacral ependymomas is good, with a greater than 90% 10-year patient survival in most series. The prognosis for extradural ependymomas does not appear to be as good. Much depends on extradural tumor location, however; the outlook is better for dorsal sacral tumors than presacral tumors.

Adolescent↗
PubMed2003

Cervical spinal metastasis: anterior reconstruction and stabilization techniques after tumor resection.

OBJECT: In a review of the literature, the authors provide an overview of various techniques that have evolved for reconstruction and stabilization after resection for metastatic disease in the subaxial cervical spine. METHODS: Reconstruction and stabilization of the cervical spine after vertebral body (VB) resection for metastatic tumor is an important goal in the surgical management of spinal metastasis. Generally, the VB defect is reconstructed with bone autograft or allograft, polymethylmethacrylate (PMMA), interbody spacers, and/or cages. In cases of PMMA-assisted reconstruction, internal devices are used to augment the fixation of PMMA. Stabilization is then achieved with anterior instrumentation, usually an anterior cervical locking plate. In some cases, posterior instrumentation may be necessary to supplement the anterior construct. CONCLUSIONS: Anterior cervical corpectomy followed by reconstruction and stabilization is an effective strategy in the management of spinal metastases in patients.

Bone Cements↗
PubMed2003

Surgical management of aneurysmal bone cysts of the spine.

OBJECT: Aneurysmal bone cysts of the spine are benign, highly vascular osseous lesions of unknown origin that may present difficult diagnostic and therapeutic challenges. They are expansile lesions containing thin-walled, blood-filled cystic cavities that cause bone destruction and sometimes spinal deformity and neurological compromise. The treatment of aneurysmal bone cysts of the spine remains controversial according to the literature. In this review, the authors discuss the clinical manifestations, pathophysiological features, neuroimaging characteristics, and treatment strategies for these lesions. METHODS: Treatment options include simple curettage with bone grafting, complete excision, embolization, and radiation therapy. Reconstruction and stabilization of the spine may be warranted if deformity and instability are present. Special factors need to be considered in the management of these lesions. CONCLUSIONS: Complete excision of aneurysmal bone cysts offers the best chance of cure and spinal decompression if neurological deficits are present.

Adolescent↗
PubMed2003

Diffuse large B-cell lymphoma presenting as a sacral tumor. Report of two cases.

Primary lymphomas of the sacrum are rare tumors, reported only in a few cases in the literature. The authors describe two patients with diffuse large B-cell lymphomas presenting as a sacral tumor. In the first case a 52-year-old man presented with progressive back pain, bilateral radicular pain, and saddle block anesthesia secondary to a lytic, expansile soft-tissue mass. The mass arose from the sacrum and eroded through the right S-1 to S-4 foramina and extended into the epidural space of the spinal canal. On magnetic resonance imaging, the sacral mass enhanced homogeneously with Gd. In the second case a 64-year-old man presented with left-sided radicular pain, paresthesias, and progressive weakness due to a lytic soft-tissue mass in the left sacral ala extending into the left L-5 and S-1 foramina. Metastatic workup in each patient demonstrated unremarkable findings. In both cases, an open biopsy procedure was performed after nondiagnostic examination of needle biopsy samples. Histopathological examination showed evidence consistent with diffuse large B-cell lymphoma in both patients. In the first case the disease was classified as Stage IAE, and the patient subsequently underwent four cycles of cyclophosphamide/doxorubicin/vincristine/prednisone (CHOP)- and rituximab-based chemotherapy followed by consolidation radiotherapy. In the second case the disease was also classified as Stage IAE, and the patient underwent CHOP-based chemotherapy and consolidation radiotherapy. In both cases radiography demonstrated a decrease in size of the sacral lymphomas. The authors review the clinical, radiological, and histological features of sacral lymphomas. Lymphoma should be considered in the differential diagnosis of sacral tumors.

Antibodies, Monoclonal↗
PubMed2003

Nerve sheath tumors involving the sacrum. Case report and classification scheme.

Nerve sheath tumors that involve the sacrum are rare. Delayed presentation is common because of their slow-growing nature, the permissive surrounding anatomical environment, and nonspecific symptoms. Consequently, these tumors are usually of considerable size at the time of diagnosis. The authors discuss a case of a sacral nerve sheath tumor. They also propose a classification scheme for these tumors based on their location with respect to the sacrum into three types (Types I-III). Type I tumors are confined to the sacrum; Type II originate within the sacrum but then locally metastasize through the anterior and posterior sacral walls into the presacral and subcutaneous spaces, respectively; and Type III are located primarily in the presacral/retroperitoneal area. The overwhelming majority of sacral nerve sheath tumors are schwannomas. Neurofibromas and malignant nerve sheath tumors are exceedingly rare. Regardless of their histological features, the goal of treatment is complete excision. Adjuvant radiotherapy may be used in patients in whom resection was subtotal. Approaches to the sacrum can generally be classified as anterior or posterior. Type I tumors may be resected via a posterior approach alone, Type III may require an anterior approach, and Type II tumors usually require combined anterior-posterior surgery.

Accidents, Traffic↗
PubMed2003

Diagnosis and management of sacral Tarlov cysts. Case report and review of the literature.

Perineurial (Tarlov) cysts are meningeal dilations of the posterior spinal nerve root sheath that most often affect sacral roots and can cause a progressive painful radiculopathy. Tarlov cysts are most commonly diagnosed by lumbosacral magnetic resonance imaging and can often be demonstrated by computerized tomography myelography to communicate with the spinal subarachnoid space. The cyst can enlarge via a net inflow of cerebrospinal fluid, eventually causing symptoms by distorting, compressing, or stretching adjacent nerve roots. It is generally agreed that asymptomatic Tarlov cysts do not require treatment. When symptomatic, the potential surgery-related benefit and the specific surgical intervention remain controversial. The authors describe the clinical presentation, treatment, and results of surgical cyst fenestration, partial cyst wall resection, and myofascial flap repair and closure in a case of a symptomatic sacral Tarlov cyst. They review the medical literature, describe various theories on the origin and pathogenesis of Tarlov cysts, and assess alternative treatment strategies.

Case Management↗
PubMed2003

Embolization of sacral tumors.

The management of sacral tumors is challenging because of difficulties in accessing the lesion, the high rate of local recurrence, extensive vascularity causing significant intraoperative blood loss, resistance to radiation therapy, and risk of malignant transformation. Although surgery is the main treatment for many sacral tumors, embolization is a valuable primary and adjunctive therapy. Patients with benign lesions, including aneurysmal bone cysts and giant cell tumors, have responded to embolization with resolution of their symptoms and with ossification of their lesions. Embolization is used as a primary therapy for metastatic lesions and results in neurological improvement, reduced tumor size, and decreased spinal canal compromise. It is also used as an adjuvant therapy to reduce intraoperative blood loss and to aid in the resection of benign, malignant, and metastatic sacral lesions. It is important to note that embolization techniques are a valuable resource in the treatment of sacral tumors, and, overall, embolization should always be considered in patients with sacral tumors.

Bone Cysts, Aneurysmal↗
PubMed2003

Spinal meningiomas: surgical management and outcome.

Advances in imaging and surgical technique have improved the treatment of spinal meningiomas; these include magnetic resonance imaging, intraoperative ultrasonography, neuromonitoring, the operative microscope, and ultrasonic cavitation aspirators. This study is a retrospective review of all patients treated at a single institution and with a pathologically confirmed diagnosis of spinal meningioma. Additionally the authors analyze data obtained in 556 patients reported in six large series in the literature, evaluating surgical techniques, results, and functional outcomes. Overall, surgical treatment of spinal meningiomas is associated with favorable outcomes. Spinal meningiomas can be completely resected, are associated with postoperative functional improvement, and the rate of recurrence is low.

Aged↗
PubMed2003

Hypophysial transposition (hypophysopexy) for radiosurgical treatment of pituitary tumors involving the cavernous sinus. Technical note.

Stereotactic radiosurgery (SRS) is performed with increasing frequency in the treatment of residual or recurrent pituitary adenomas. Its major associated risk in these cases of residual or recurrent pituitary tumor adjacent to normal functional pituitary gland is radiation exposure to the pituitary, which frequently leads to the development of hypopituitarism. The authors describe a technique of pituitary transposition to reduce the radiation dose to the normal pituitary gland in cases of planned radiosurgical treatment of residual pituitary adenoma within the cavernous sinus. A sellar exploration for tumor resection is performed, the pituitary gland is transposed from the region of the cavernous sinus, and a fat and fascia graft is interposed between the normal pituitary gland and the residual tumor in the cavernous sinus. The residual tumor may then be treated with SRS. The increased distance between the normal pituitary gland and the residual tumor facilitates treatment of the tumor with radiosurgery and reduces radiation exposure to the normal pituitary gland.

Adolescent↗
PubMed2003

The role of PCV chemotherapy in the treatment of central neurocytoma: illustration of a case and review of the literature.

BACKGROUND: Most central neurocytomas follow a benign clinical course. However, more aggressive variants have been described requiring additional surgical resection, radiation, or chemotherapy. Chemotherapy has rarely been used as an adjuvant therapy for central neurocytomas. METHODS: We report a case of a 20-year-old girl who underwent four subtotal resections, over the course of 3 years, for a large central neurocytoma that continued to progress. She was not a candidate for stereotactic radiosurgery, given the large tumor size. To avoid radiation injury in a young patient, she was treated with six cycles of chemotherapy including procarbazine, CCNU, and vincristine. Procarbazine was stopped after 2 cycles because of the development of a rash. Serial magnetic resonance imaging was used to follow treatment response. RESULTS: Her tumor started to decrease in size after 2 cycles of chemotherapy and continued to shrink until it stabilized after 5 cycles of chemotherapy. A small area of residual tumor with minimal enhancement persisted along the left lateral ventricle and remained stable for at least 16 months after the completion of chemotherapy. CONCLUSIONS: To our knowledge, this is only the fourth report describing the use of chemotherapy for progression of central neurocytomas as a treatment alternative to radiation therapy. The use of procarbazine, CCNU, and vincristine has not been previously described for the treatment of a central neurocytoma and presents an additional treatment option.

Adolescent↗
PubMed2003

Repeated operations for infiltrative low-grade gliomas without intervening therapy.

OBJECT: Progression of infiltrative low-grade gliomas (LGGs) has been reported previously. The limitations of such studies include diverse histological grading systems, intervening therapy, and the lack of histological confirmation of malignant tumor progression. The aim of this study was to determine tumor progression in adult patients with an initial diagnosis of infiltrative LGG who subsequently underwent a repeated operation, but no other intervening therapy. The authors examined factors that may be associated with tumor progression. METHODS: The authors retrospectively reviewed a database of 300 patients with the initial diagnosis of LGG and who had been treated at their institution between 1990 and 2000. One hundred four of these patients had undergone a second surgery. Patients with infiltrative LOGs who had undergone two surgical procedures at least 3 months apart without intervening therapy were selected; the authors identified 40 patients who fit these criteria. Clinical, neuroimaging, and pathological data were centrally reviewed. There were 29 men and 11 women in the study, whose median age was 35.5 years (range 23-48 years). At the time of the second surgery, 50% of patients had experienced tumor progression. Patients whose tumors had progressed had a longer median time to repeated operation (49 compared with 22.5 months). Patients who had undergone gross-total resection, as demonstrated on postoperative magnetic resonance images, had a median time to repeated operation of 49 compared with 25 and 24 months in patients who underwent subtotal resection and biopsy, respectively (p = 0.02). The extent of resection did not influence the likelihood of tumor progression (p > 0.3). CONCLUSIONS: Fifty percent of patients with initially diagnosed infiltrative LGOs had tumor progression at the time of a repeated operation. A gross-total resection was associated with an increased time to repeated surgery. There was no statistically significant effect of gross-total resection as a predictor of tumor progression.

Adult↗
PubMed2003

Perioperative complications and neurological outcomes of first and second craniotomies among patients enrolled in the Glioma Outcome Project.

OBJECT: In many new clinical trials of patients with malignant gliomas surgical intervention is incorporated as an integral part of tumor-directed interstitial therapies such as gene therapy, biodegradable wafer placement, and immunotherapy. Assessment of toxicity is a major component of evaluating these novel therapeutic interventions, but this must be done in light of known complication rates of craniotomy for tumor resection. Factors predicting neurological outcome would also be helpful for patient selection for surgically based clinical trials. METHODS: The Glioma Outcome Project is a prospectively compiled database containing information on 788 patients with malignant gliomas that captured clinical practice patterns and patient outcomes. Patients in this series who underwent their first or second craniotomy were analyzed separately for presenting symptoms, tumor and patient characteristics, and perioperative complications. Preoperative and intraoperative factors possibly related to neurological outcome were evaluated. There were 408 patients who underwent first craniotomies (C1 group) and 91 patients who underwent second ones (C2 group). Both groups had similar patient and tumor characteristics except for their median age (55 years in the C1 group compared with 50 years in the C2 group; p = 0.006). Headache was more common at presentation in the C1 group, whereas papilledema and an altered level of consciousness were more common at presentation in patients undergoing second surgeries. Perioperative complications occurred in 24% of patients in the C1 group and 33% of patients in the C2 group (p = 0.1). Most patients were the same or better neurologically after surgery, but more patients in the C2 group (18%) displayed a worsened neurological status than those in the C1 group (8%; p = 0.007). The Karnofsky Performance Scale score and, in patients in the C2 group, tumor size were important neurological outcome predictors. Regional complications occurred at similar rates in both groups. Systemic infections occurred more frequently in the C2 group (4.4 compared with 0%; p < 0.0001) as did depression (20 compared with 11%; p = 0.02). The perioperative mortality rate was 1.5% for the C1 group and 2.2% for the C2 group (p = not significant). The median length of the hospital stay was 4 days in each group. CONCLUSIONS: Perioperative complications occur slightly more often following a second craniotomy for malignant glioma than after the first craniotomy. This should be considered when evaluating toxicities from intraoperative local therapies requiring craniotomy. Nevertheless, most patients are neurologically stable or improved after either their first or second craniotomy. This data set may serve as a benchmark for neurosurgeons and others in a discussion of operative risks in patients with malignant gliomas.

Central Nervous System Neoplasms↗