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John E Wanebo

Publications and source records attributed to John E Wanebo.

11 recordsLinked to original sources
PubMed2006

Computed tomographic angiography for the evaluation of aneurysmal subarachnoid hemorrhage.

OBJECTIVES: Computed tomography (CT) followed by lumbar puncture (LP) is currently the criterion standard for diagnosing subarachnoid hemorrhage (SAH) in the emergency department (ED); however, this is based on studies involving a limited number of patients. The authors sought to assess the ability of CT angiography (CTA), a new diagnostic modality, in conjunction with CT/LP to detect SAH. METHODS: Consecutive patients presenting to the ED with symptoms concerning for SAH were approached. All patients had an intravenous catheter placed and underwent a noncontrast head CT followed by CTA. Patients whose CT did not reveal evidence of SAH or other pathology underwent LP in the ED. CTAs were read within 24 hours by a neuroradiologist blinded to the patient's history. RESULTS: A total of 131 patients were approached, 116 were enrolled, and 106 completed the study. In six of 116 patients (5.1%), aneurysm was found on CTA with normal CT and positive findings on LP; three had a positive CTA with normal CT and LP findings (one of which had a negative cerebral angiogram), and there was one false-positive CTA. Follow-up of all 131 patients showed no previously undiagnosed intracranial pathology. In this patient population, 4.3% (5/116) were ultimately found to have an SAH and/or aneurysm. CONCLUSIONS: In this pilot study, CTA was found to be useful in the detection of cerebral aneurysms and may be useful in the diagnosis of aneurysmal SAH. A larger multicenter study would be useful to confirm these results.

Adult↗
PubMed2006

Management of cranial base chondrosarcomas.

OBJECTIVE: Chondrosarcomas are rare, infiltrative, progressive lesions that occur at the cranial base. Their intimate association with cranial nerves and major vessels of the head and neck often precludes complete surgical resection. METHODS: Between 1983 and 2003, 23 patients (14 females, 9 males) were treated at our institution with the diagnosis of chondrosarcoma of the cranial base (mean age at presentation, 43 yr). A retrospective chart review was performed to evaluate presentation, management, and adjunctive treatment. All living patients were contacted for a current examination and disease status. RESULTS: The 23 patients underwent 43 surgical resections. Follow-up ranged from 8 months to 25 years (mean, 97 mo). Ten patients underwent various adjuvant radiation therapies. Five patients have died. Four patients have no evidence of disease, and 13 have residual tumor. One was lost to follow-up. Of 14 patients with 5 years of follow-up, 13 are living. Therefore, the absolute 5 year survival rate is 93%. The 10 year survival rate is 71%. CONCLUSION: Because of the intricate nature of the cranial base, a team approach is preferable for managing these challenging lesions. Maximum cytoreductive surgery should be pursued as an initial strategy to minimize neurological injury. Adjuvant stereotactic radiosurgery can be used to treat residual disease or small recurrences. This cohort also illustrates that patients with chondrosarcomas have better long-term survival rates than patients with chordomas of the cranial base.

Adolescent↗
PubMed2005

Assessing success after cerebral revascularization for ischemia.

Cerebral revascularization continues to evolve as an option in the setting of ischemia. The potential to favorably influence stroke risk and the natural history of cerebrovascular occlusive disease is being evaluated by the ongoing Carotid Occlusion Surgery Study and the Japanese Extracranial-Intracranial Bypass Trial. For those patients who undergo bypass in the setting of ischemia, four key areas of follow-up include functional neurological status, neurocognitive status, bypass patency, and status of cerebral blood flow and perfusion. Several stroke scales that can be used to assess functional status include the National Institutes of Health Stroke Scale, Bathel Index, Modified Rankin Scale, and Stroke Specific Quality of Life. Neurocognition can be checked using the Repeatable Battery for the Assessment of Neuropsychological Status, among other tests. Bypass patency is checked intraoperatively using various flow probes and postoperatively using magnetic resonance angiography (MRA) or computed tomographic angiography (CTA). Cerebral blood flow and perfusion can be assessed using a host of modalities that include positron emission tomography (PET), xenon CT, single photon emission computed tomography (SPECT), transcranial Doppler (TCD), CT, and MR. Paired blood flow studies after a cerebral vasodilatory stimulus using one of these modalities can determine the state of autoregulatory vasodilation (Stage 1 hemodynamic compromise). However, only PET with oxygen extraction fraction measurements can reliably assess for Stage 2 compromise (misery perfusion). This article discusses the various clinical, neuropsychological, and radiographic techniques available to assess a patient's clinical state and cerebral blood flow before and after cerebral revascularization.

Journal Article↗
PubMed2005

Graft harvesting for revascularization in the head and neck.

The techniques for revascularization in the neurocranium, skull base, and neck continue to evolve at an exciting pace. In this body of literature, however, techniques for harvesting radial artery and saphenous vein grafts are mainly reported using traditional open techniques. Minimally invasive procedures are fast becoming an alternative to open techniques in many fields and have the potential to become the standard of care. The cardiovascular literature is replete with reports of endoscopically harvested vascular grafts. This article reviews both methods, since the current state of the art involves knowledge of open and endoscopic harvesting techniques.

Journal Article↗
PubMed2005

Use of a side branch in a saphenous vein interposition graft for high-flow extracranial-intracranial bypass procedures. Technical note.

Saphenous vein (SV) interposition grafts are often used for high-flow extracranial-intracranial bypass procedures. During these procedures, it is essential to remove air and debris from the graft and to evaluate blood flow through the graft after it has been anastomosed to other cortical vessels. In this paper, the authors describe the preservation of a large side branch on the proximal end of the SV. This side branch can be used to flush out air and debris from the graft and to evaluate blood flow during revascularization.

Cerebral Revascularization↗
PubMed2004

Superficial temporal artery-to-middle cerebral artery bypass grafting for cerebral revascularization.

Superficial temporal artery-to-middle cerebral artery bypass procedures are an important tool in the armamentarium of cerebrovascular surgeons for the treatment of carotid occlusion and revascularization for complex aneurysms and brain tumors. This article enumerates the essential steps in performing superficial temporal artery-to-middle cerebral artery bypass procedures. The nuances of this technique reflect the extensive experience of the senior authors.

Anastomosis, Surgical↗
PubMed2003

The natural history of hemangioblastomas of the central nervous system in patients with von Hippel-Lindau disease.

OBJECT: The goals of this study were to define the natural history and growth pattern of hemangioblastomas of the central nervous system (CNS) that are associated with von Hippel-Lindau (VHL) disease and to correlate features of hemangioblastomas that are associated with the development of symptoms and the need for treatment. METHODS: The authors reviewed serial magnetic resonance images and clinical histories of 160 consecutive patients with VHL disease who harbored CNS hemangioblastomas and serially measured the volumes of tumors and associated cysts Six hundred fifty-five hemangioblastomas were identified in the cerebellum (250 tumors), brainstem (64 tumors, all of which were located in the posterior medulla oblongata), spinal cord (331 tumors, 96% of which were located in the posterior half of spinal cord), and the supratentorial brain (10 tumors). The symptoms were related to a mass effect. A serial increase in hemangioblastoma size was observed in cerebellar, brainstem, and spinal cord tumors as patients progressed from being asymptomatic to symptomatic and requiring surgery (p < 0.0001). Twenty-one (72%) of 29 symptom-producing cerebellar tumors had an associated cyst, whereas only 28 (13%) of 221 nonsymptomatic cerebellar tumors had tumor-associated cysts (p < 0.0001). Nine (75%) of 12 symptomatic brainstem tumors had associated cysts, compared with only four (8%) of 52 nonsymptomatic brainstem lesions (p < 0.0001). By the time the symptoms appeared and surgery was required, the cyst was larger than the causative tumor; cerebellar and brainstem cysts measured 34 and 19 times the size of their associated tumors at surgery, respectively. Ninety-five percent of symptom-producing spinal hemangioblastomas were associated with syringomyelia. The clinical circumstance was dynamic. Among the 88 patients who had undergone serial imaging for 6 months or longer (median 32 months), 164 (44%) of 373 hemangioblastomas and 37 (67%) of 55 tumor-associated cysts enlarged. No tumors or cysts spontaneously diminished in size. Symptomatic cerebellar and brainstem tumors grew at rates six and nine times greater, respectively, than asymptomatic tumors in the same regions. Cysts enlarged seven (cerebellum) and 15 (brainstem) times faster than the hemangioblastomas causing them. Hemangioblastomas frequently demonstrated a pattern of growth in which they would enlarge for a period of time (growth phase) and then stabilize in a period of arrested growth (quiescent phase). Of 69 patients with documented tumor growth, 18 (26%) harbored tumors with at least two growth phases. Of 160 patients with hemangioblastomas, 34 patients (median follow up 51 months) were found to have 115 new hemangioblastomas and 15 patients new tumor-associated cysts. CONCLUSION: In this study the authors define the natural history of CNS hemangioblastomas associated with VHL disease. Not only were cysts commonly associated with cerebellar, brainstem, and spinal hemangioblastomas, the pace of enlargement was much faster for cysts than for hemangioblastomas. By the time symptoms appeared, the majority of mass effect-producing symptoms derived from the cyst, rather than from the tumor causing the cyst. These tumors often have multiple periods of tumor growth separated by periods of arrested growth, and many untreated tumors may remain the same size for several years. These characteristics must be considered when determining the optimal timing of screening for individual patients and for evaluating the timing and results of treatment.

Adult↗
PubMed2003

Surgical management of brainstem hemangioblastomas in patients with von Hippel-Lindau disease.

OBJECT: Hemangioblastomas of the brainstem constitute 5 to 10% of central nervous system (CNS) tumors in patients with von Hippel-Lindau (VHL) disease. At present, optimal management of brainstem hemangioblastomas associated with VHL disease is incompletely defined. In an attempt to clarify some of the uncertainty about the operative treatment of these lesions and its outcome, the authors reviewed all cases of VHL disease in which resection of brainstem hemangioblastomas was performed at the National Institutes of Health during a 10-year period. METHODS: Twelve consecutive patients with VHL disease (six male and six female patients [mean age 31.7 +/- 9 years; range 15-46 years]) who underwent 13 operations to remove 17 brainstem hemangioblastomas were included in this study (mean follow-up period, 88.4 +/- 37.4 months; range 37-144 months). Serial examinations, hospital charts, magnetic resonance images, and operative records were reviewed. To evaluate clinical course, clinical grades were assigned to each patient before and after surgery. Preoperative neurological function was the best predictor of long-term outcome. In addition, patients who underwent CNS surgeries for hemangioblastomas were more likely to improve or to remain neurologically stable. Tumor or cyst size, the presence of a cyst, or the location of the tumor (intramedullary, extramedullary, or mixed; posterior medullary, obex, or lateral) did not affect outcome. No patient was neurologically worse after brainstem surgery. At long-term follow-up review (mean 88.4 months), only one patient had declined neurologically and this was due to the cumulative neurological effects caused by eight additional hemangioblastomas of the spinal cord and their surgical treatment. CONCLUSIONS: Brainstem hemangioblastomas in patients with VHL disease can be removed safely; they generally should be resected when they become symptomatic or when the tumor has reached a size such that further growth will increase the risks associated with surgery, or in the presence of an enlarging cyst. Magnetic resonance imaging is usually sufficient for preoperative evaluation and presurgical embolization is unnecessary. The goal of surgery is complete resection of the lesion before the patient experiences a disabling neurological deficit.

Adolescent↗
PubMed2003

Surgical management of spinal cord hemangioblastomas in patients with von Hippel-Lindau disease.

OBJECT: Von Hippel-Lindau (VHL) disease is an autosomal-dominant disorder frequently associated with hemangioblastomas of the spinal cord. Because of the slow progression, protean nature, and high frequency of multiple spinal hemangioblastomas associated with VHL disease, the surgical management of these lesions is complex. Because prior reports have not identified the factors that predict which patients with spinal cord hemangioblastomas need surgery or what outcomes of this procedure should be expected, the authors have reviewed a series of patients with VHL disease who underwent resection of spinal hemangioblastomas at a single institution to identify features that might guide surgical management of these patients. METHODS: Forty-four consecutive patients with VHL disease (26 men and 18 women) who underwent 55 operations with resection of 86 spinal cord hemangioblastomas (mean age at surgery 34 years; range 20-58 years) at the National Institutes of Health were included in this study (mean clinical follow up 44 months). Patient examination, review of hospital charts, operative findings, and magnetic resonance imaging studies were used to analyze surgical management and its outcome. To evaluate the clinical course, clinical grades were assigned to patients before and after surgery. Preoperative neurological status, tumor size, and tumor location were predictive of postoperative outcome. Patients with no or minimal preoperative neurological dysfunction, with lesions smaller than 500 mm3, and with dorsal lesions were more likely to have no or minimal neurological impairment. Syrinx resolution was the result of tumor removal and was not influenced by whether the syrinx cavity was entered. CONCLUSIONS: Spinal cord hemangioblastomas can be safely removed in the majority of patients with VHL disease. Generally in these patients, hemangioblastomas of the spinal cord should be removed when they produce symptoms or signs.

Adult↗