Rhythmic attentional sampling in autism.

Individuals diagnosed with autism often display alterations in visual spatial attention toward visual stimuli, but the underlying cause of these differences remains unclear. Recent evidence has demonstrated that covert spatial attention, rather than remaining constant at a cued location, samples stimuli rhythmically at a frequency of 4-8 Hz (theta). Here we tested whether rhythmic sampling of attention is altered in autism.

Defining radiographic criteria for flexion-extension studies of the cervical spine.

Study Objective: We sought to describe and measure 3 radiographic variables in normal male volunteers and determine whether these variables could be useful in establishing more objective radiographic criteria for evaluation of flexion-extension studies of the cervical spine. In addition, we hypothesized that patients with a normal cervical spine should not have greater than 2 mm of subluxation present with flexion or extension.

Methods: A prospective, observational study of normal male volunteers between the ages of 18 and 40 years was performed.

Thallium-201 brain SPECT of lymphoma in AIDS patients: pitfalls and technique optimization.

Purpose: Our aim was to examine the 201Tl-SPECT scans in AIDS patients with focal CNS lesions to identify those studies with a false-positive or false-negative result to determine any potential pitfalls in interpretation as well as to suggest methods for technique optimization.

Methods: We retrospectively reviewed the charts of 162 AIDS patients with cerebral mass lesions on 201Tl-SPECT studies. One hundred sixty-one patients had CT examinations, of which 50 also had MR studies.

Intra-aortic balloon counterpulsation augments cerebral blood flow in the patient with cerebral vasospasm: a xenon-enhanced computed tomography study.

Objective: We previously established the ability of intra-aortic balloon counterpulsation (IABC) to improve cerebral blood flow (CBF) significantly in a canine model of cerebral vasospasm. This study was performed to assess the efficacy of IABC in a patient with cardiac dysfunction and severe cerebral vasospasm that was refractory to traditional treatment measures.

Methods: We report our experience with the clinical use of IABC to treat cerebral vasospasm in a patient who suffered subarachnoid hemorrhage and concomitant myocardial infarction.

Nuclear medicine applications to the neuroimaging of AIDS. A neuroradiologist's perspective.

The human immunodeficiency virus (HIV) responsible for AIDS is reaching epidemic proportions in the United States and Europe. As new therapeutic modalities against HIV are uncovered and applied to treat prophylactically asymptomatic and therapeutically symptomatic HIV positive patients, imaging studies are no longer used just to characterize the organic-morphologic effects of HIV and opportunistic infections and neoplasms. This article discusses the current applications and contribution of nuclear medicine to the management of neurologically symptomatic HIV-positive patients.