Diagnostic Neuroimaging Research Articles

Outcomes and failure patterns in childhood craniopharyngiomas.

Past studies of craniopharyngiomas in children have shown overall survival (OS) up to 95% at 5 years and 80% progression-free survival (PFS) at 5 years, although many of these series predate modern neuroimaging and current therapeutic management. Moreover, little mention has been made of failure patterns for craniopharyngioma in children. To obtain a contemporary assessment of outcome among pediatric craniopharyngioma patients, and also to determine the failure patterns for this tumor, we completed a retrospective study of a consecutive cohort of all children with craniopharyngioma diagnosed at the Johns Hopkins Hospital from 1980 to 1996. Resection was performed in 30 children, in 8 of whom gross total resection (GTR) was achieved. Initial treatment took the form of GTR followed by observation for 8, subtotal resection (STR) plus observation in 11, and STR followed immediately by radiotherapy in 8. The timing of radiotherapy following STR was unclear for 3. OS was 95.2% (SE= 4.7%) at 5 years, with only 2 children dying after 4 years from diagnosis. Five-year PFS was 59.4% (SE=10.2%). Before surgery, 19 children had visual loss and 15, endocrine deficits; after surgery, 21 children had visual loss and 29, endocrine deficits. Median time to relapse was 0.98 years (SD=2.5 years). Radiographic (n=4) and clinical (n=7) relapses did not differ in time to progression (P=0.32), but radiographic relapses were significantly associated with age at diagnosis less than 5 years (P=0.02). Degree of resection was not significantly associated with PFS (P=0.32) or with postoperative visual or endocrine deficits. Absence of calcification on diagnostic neuroimaging (n=8) was significantly associated with improved PFS [5-year PFS 100% vs. 42.9% (SE=14.7%), P=0.02], even when adjusted for extent of resection (P=0.03). Preoperative visual loss was predictive of postoperative visual loss (P=0.03). Survival for children diagnosed with craniopharyngioma in the current era is outstanding, even with relapse, although postoperative visual and endocrinological morbidities are high. Failures occurred both radiographically and clinically, typically in the first 3-4 years after surgery, suggesting a need for close surveillance initially with neuroimaging, particularly in younger children, and also clinical examination. The short times to relapse observed here may stem from a tendency to delay radiotherapy until recurrence. Lack of calcification at diagnosis is associated with a tendency to remain free of relapse.

NEURORADIOLOGY IN OPHTHALMOLOGY

Technical advances made in diagnostic neuroimaging during the past 20 years have played an important role in the practice of ophthalmology. Various diagnostic tests are now routinely used to image the globe, orbit, and intracranial visual pathways. With so many different imaging modalities available, choosing the appropriate study to evaluate a clinical problem has become more difficult. This discussion highlights the current techniques available to image the eye, ocular adnexa, and brain. It also provides guidance on the selection of the appropriate imaging modality and several examples of imaging characteristics of pathologic lesions.

Topical Review Article: Brainstem Glioma: I. Pathology, Clinical Features, and Therapy

Gliomas that arise in the brain stem have been associated with a poor prognosis. Diagnostic neuroimaging readily identifies the tumor as it extends between normal brainstem structures. Histologic sampling of tumor with stereotactic methods is notoriously unreliable in establishing a definitive prognosis. Clinical trials that incorporate high-dose chemotherapy, autologous bone marrow rescue, and irradiation hold promise of better tumor control by overcoming the inaccessibility of the central nervous system to standard doses of chemotherapy. We review the pathology, clinical features, neuroimaging features, and current therapeutic concepts relative to brainstem glioma. The pediatric neurologist has a pivotal role in identifying and monitoring children with this malignancy.

Diagnostic neuroimaging in stroke. The complementary roles of referring physician and neuroradiologist.

The number and sophistication of neuroimaging methods for identifying location, size, type, and causes of stroke or stroke-like syndromes have expanded rapidly. In acute stroke, computed tomography is used to distinguish between nonhemorrhagic and hemorrhagic infarction and to eliminate several potential alternative diagnoses. Cerebral angiography can identify surgically treatable lesions in patients experiencing transient ischemic attacks and thus aid in preventing stroke. The superb sensitivity of magnetic resonance imaging has opened new vistas in the ongoing investigation of multiinfarct dementia and small infarcts in neurologically "noneloquent" regions of the brain. The more complete the referring physician's clinical and neurologic workup, the more able is the neuroradiologist to structure and coordinate the safest, fastest, and most cost-effective plan of neuroimaging to diagnose a patient's neurologic problem.