Synthesized image processing in clinical neurosurgery.

In an effort to achieve efficient image management in clinical neurosurgery utilizing a local image filing system (EFPACS, Fuji Electric Co., Ltd), adequate image-processing and display techniques were developed. One is a method whereby the anatomical location of the thalamic and basal ganglion lesions is determined by automatically superimposing these lesions defined by magnetic resonance imaging (MRI) directly onto the Schaltenbrand-Wahren's human brain atlas. Horizontal, coronal and sagittal MR images are initially obtained based on the intercommissural line and a perpendicular erected on the midcommissural point as the basic reference coordinates. Precise superimposition is accomplished by the use of these reference axes. This imaging technique may offer the potential for help in anatomical identification of small intracranial lesions. Another technique described in the current communication is automated synthesis of two cerebral angiograms. By simply indicating two reference points, nasion and inion, with a cursor on the display screen, two films are automatically superimposed and displayed as a single synthesized image, featuring two different vascular phases simultaneously by a positive(vein)-negative(artery) mode. This technique was applied to patients with complete occlusion of the middle cerebral artery with or without sufficient blood flow through collateral circulation and was found useful in evaluating basic hemodynamics on a single angiographic image.