DICOM (Digital Imaging and Communications in Medicine) Working Group XI, formerly called ACR/NEMA (American College of Radiology/National Electrical Manufacturers' Association) Working Group XI, is currently developing a display function standard. The main objective of the standard is to define mathematically a display function for all image presentation systems. As a secondary objective, the standard aims at providing similarity in gray-scale perception for a given image between display systems of different luminance and at facilitating efficient utilization of the available digital input levels of a display system. The design of the display function incorporates the concept of perceptual linearization. The proposed standard applies to monochrome image presentation devices such as cathode ray tube monitor-display controller systems and digital laser image printers. The standard does not eliminate the use of application-specific display functions but rather ensures their effectiveness. Neither does the standard guarantee equal information transfer between image presentation devices with different physical properties; it does, however, from the basis for applying image processing to compensate for such differences.

Data Display↗

PubMedDate not supplied

Pituitary adenoma with seizures: PET demonstration of reduced glucose utilization in the medial temporal lobe.

A patient with a benign chromophobe adenoma, who had incomplete surgical removal followed by radiotherapy, continued to have epileptic seizures up to two or three times a day. She was studied with positron emission tomography using 18F-2-deoxyglucose (FDG). This technique showed a high level of glucose utilization in the area of the operated tumor but also clear reduction of glucose utilization in the left medial temporal region adjacent to the sella and the scar tissue from the neoplasm. This area of reduced glucose utilization corresponded well to the same finding observed in other patients with complex partial epilepsy. A left temporal anterior lobectomy was carried out followed by improved control of the epilepsy. Positron emission tomography using FDG, together with electrophysiological examinations, may assist in the management of epilepsy related to pituitary tumors.

Adenoma, Chromophobe↗

PubMedDate not supplied

Cervicogenic headache. Long-term results of radiofrequency treatment of the planum nuchale.

Seven female patients, all fulfilling the current criteria for cervicogenic headache, underwent radiofrequency treatment of the periosteum of the external surface of the occipital bone ("planum nuchale") on the symptomatic side, as described by Blume. The patients were followed up for approximately 4.5 years postoperatively. In three patients, the operation was considered completely successful (43%), whereas it was completely unsuccessful in two patients. In the two remaining patients, a considerable improvement (60-70%) was obtained. Thus, in 71% of the patients, an improvement of varying degree was obtained. In one of the patients who did not improve, a local effusion developed in the wake of the procedure. In the future, this procedure will probably be one of the therapeutic options for cervicogenic headache. These results provide further evidence establishing cervicogenic headache as a disorder, distinguishable from common migraine ("migraine without aura").

Adult↗