The statistical quality of conventional nuclear medical imagery is limited by the small signal collected through low-efficiency conventional apertures. Coded-aperture imaging overcomes this by employing a two-step process in which the object is first efficiently detected as an "encoded" form which does not resemble the object, and then filtered (or "decoded") to form an image. We present here the imaging properties of a class of time-modulated coded apertures which, unlike most coded apertures, encode projections of the object rather than the object itself. These coded apertures can reconstruct a volume object nontomographically, tomographically (one plane focused), or three-dimensionally. We describe a new decoding algorithm that reconstructs the object from its planar projections. Results of noise calculations are given, and the noise performance of these coded-aperture systems is compared to that of conventional counterparts. A hybrid slit-pinhole system which combines the imaging advantages of a rotating slit and a pinhole is described. A new scintillation detector which accurately measures the position of an event in one dimension only is presented, and its use in our coded-aperture system is outlined. Finally, results of imaging test objects and animals are given.

Animals↗

PubMedDate not supplied

Treatment failure in anterior uveitis in children.

Anterior uveitis in children can present difficult management problems. While the course of the inflammation may defy the usual treatment modalities, attention to five specific areas of clinical management may enable the ophthalmologist to better preserve visual function. Careful examination, proper adjustment of corticosteroid dosage, repeated intraocular pressure measurement, patient compliance, and adequate follow-up are the areas discussed.

Child↗

PubMedDate not supplied

Peripheral uveitis in three children of one family.

Peripheral uveitis presenting in three siblings is described. The course and response to treatment in each youngster is detailed. Periocular and local corticosteroid therapy was effective. Etiologic evaluation and immunologic surveys proved unrewarding. Ophthalmological evaluation of families seems warranted following the detection of peripheral uveitis in any of its members.

Adrenal Cortex Hormones↗

PubMedDate not supplied

Results of overminus lens therapy on postoperative exodeviations.

This paper is a study in the use of overminus lenses for 37 patients with postoperative exodeviations. These patients have been observed for a period ranging from three to nine years following their surgery. This study includes: (1) the immediate response to overminus treatment, (2) results at the time of cessation of overminus therapy, and (3) the follow-up results. The results are evaluated with an average follow-up of 24 months after termination of treatment and sequentially at one-year intervals following overminus therapy.

Child↗