The presence and degree of pancreatic necrosis (30%, 50%, or greater than 50%) was evaluated by means of bolus injection of contrast material and dynamic sequential computed tomography (CT) in 88 patients with acute pancreatitis at initial and follow-up examinations. Pancreatic necrosis was defined as lack of enhancement of all or a portion of the gland. Length of hospitalization, morbidity, and mortality in patients with early or late necrosis (22 patients) were evaluated and compared with the same criteria in the rest of the group. Patients with necrosis had a 23% mortality and an 82% complication rate; patients without necrosis had 0% mortality and 6% morbidity. When only the initial assessment was considered, patients with peripancreatic phlegmons and necrosis had 80% morbidity, compared with 36% morbidity in those with phlegmons and no necrosis. Serious complications occurred in patients who initially had or developed more than 30% necrosis. A CT severity index, based on a combination of peripancreatic inflammation, phlegmon, and degree of pancreatic necrosis as seen at initial CT study, was developed. Patients with a high CT severity index had 92% morbidity and 17% mortality; patients with a low CT severity index had 2% morbidity, and none died.

We are able to move visual attention away from the direction of gaze, fixating on one object while attending to something else at a different location, within the region of peripheral vision. It has been widely assumed that the attentional neural systems are separate from the motor systems, but some studies challenge this idea. It has now been suggested that the attentional system is part of the premotor processing in the brain. This model proposes that attentional processes evolved as part of the motor systems, with isolated attentional shifts representing an artificial separation of a natural linkage. Here we test how attentional shifts might be linked to the preparations for making saccadic eye movements. We studied the superior colliculus in monkeys as they shifted their attention during different tasks, and found that each attentional shift is associated with eye-movement preparation.

Abstract-Neurons in a subdivision of the pulvinar resemble those in parietal cortex: many respond to visual stimuli, some of these have a spatial selection mechanism, and some have signals about the occurrence ofeye movements. These properties suggest a role in visual spatial attention. Injection of GABA-related drugs into this part of the pulvinar alters animals' performance on an attentional task. These data support our hypothesis that the pulvinar contributes to visual spatial attention.

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