A technique is described which has been used to quantitate the 3-dimensional configuration of the midbrain dopamine (DA) nuclei (cell groups A8, A9, and A10). This technique provides cell counting information, for example, the BALB/c mouse has approximately 25,000 midbrain DA neurons, the albino rat has about 40,000 neurons, and man (33 year old) has approximately 450,000 neurons. Furthermore, cell density topography maps were constructed which enable quantitation of the 3-dimensional cellular distribution. These topography maps revealed both similarities and differences across the three species examined. The number of midbrain DA neurons is known to be genetically determined and to decrease with aging. DA cell number is also related to motoric behavior and neurologic and perhaps psychiatric disease. The ability to quantitate DA regional cell densities represents a new technique which can be used to study the neurobiology of DA neurons and relate DA cell number to both normal and abnormal behaviors.

Computer-generated three-dimensional reconstruction of the intracranial vascular system obtained by contrast-enhanced computerized tomography (CT) has been used in the diagnosis of 20 patients with known or suspected intracranial cerebrovascular disease. This technique allows visualization of the intracranial vasculature without exposing patients to the risks associated with intra-arterial angiography. The color prints and videotape images generated have been used to diagnose the presence of intracranial aneurysms, arteriovenous malformations, and venous angiomas. They have also been used to rule out structural abnormalities in patients with suspected intracranial vascular pathology and to screen patients with a strong family history of intracranial aneurysm. In 11 patients who underwent both three-dimensional CT angiography and intra-arterial angiography, the diagnostic correlation was 100%. No complications from the procedures or from incorrect diagnosis have been encountered. Although this technique requires further development and clinical evaluation, the authors' early experience with three-dimensional CT angiography suggests that this may become a valuable tool in the diagnosis of patients with cerebrovascular disease.

No abstract

Although three-dimensional computed tomographic angiography was developed as a screening tool for use in patients with suspected cerebrovascular disease, this imaging modality has also proven to be of value in surgical planning for patients with large or unusual vascular lesions of the brain. The three-dimensional images generated by this technique yield valuable information regarding the size and configuration of intracranial aneurysms and vascular malformations, the presence and extent of intra-aneurysmal thrombus, the relationship of the vascular lesion to other cerebrovascular or skeletal structures, aneurysm wall thickness, and the presence and orientation of an aneurysm neck. The use of three-dimensional computed tomographic angiography in representative cases of patients with large or unusual cerebrovascular lesions is presented. It has been our experience that this imaging modality displays anatomical information that is not readily available from standard, intra-arterial angiography, provides better detail for surgical planning than magnetic resonance angiography, and is less expensive than either of these other imaging modalities.