Biomedical subjects

A J Scheiner

Publications and source records attributed to A J Scheiner.

3 recordsLinked to original sources

PubMed1999

Ectopic brain tissue in the orbit.

PURPOSE: The authors report findings in a 9-month-old male infant with heterotopic brain tissue in the orbit, and compare and contrast the characteristics in this patient with the few other descriptions of such lesions in the literature. METHODS: Excisional biopsy of the growth was undertaken by means of an anterior orbitotomy. RESULTS: A 9-month-old male infant had a history of congenital left 'anophthalmia' and a slowly growing mass in the left orbit. An MRI scan revealed an orbital mass with solid and cystic components. Histological study of the excised tissue was performed and revealed a choristomatous arrangement of dysplastic brain tissue with intermixed primitive retina including pigmented epithelium. There was no connection between the orbit and cranial cavity. CONCLUSIONS: The mass must be considered a rare example of heterotopic brain tissue in the orbit and is the only instance we could find in the literature in which a formed eye was absent but in which a scattered primitive ocular structure could be identified.

Anophthalmos↗

PubMed1998

Intraoperative tissue expansion in eyelid reconstruction.

OBJECTIVE: Chronic tissue expansion is a well-accepted modality for increasing available tissue for reconstructive surgery. In rapid intraoperative tissue expansion (RITE), a tissue expander is used intraoperatively to increase the available tissue area for defect closure. The use of the ubiquitous and inexpensive Foley catheter has previously been reported as a tissue expander in RITE. In this paper, the authors examine the application of the Foley catheter for RITE in oculoplastic surgery. DESIGN: Case series. PARTICIPANTS: Twenty-six patients (ages 50 to 87) with eyelid defects from various causes underwent reconstruction using RITE. INTERVENTION: Using this technique, the tip of a #14 French Foley catheter is trimmed, keeping the balloon intact. The balloon is inserted under a skin-muscle flap. Counter traction is applied, and the balloon is filled with saline until the flap blanches. The balloon is inflated twice for 5 minutes with a 1- to 2-minute rest period between expansions. This provides increased tissue area for reconstruction of periocular defects. MAIN OUTCOME MEASURES: The linear extent of the eyelid defect was measured prior to and after expansion with RITE. A comparison was made between the two measurements. RESULTS: The linear extent of the eyelid margin defect decreased by 36% after RITE. CONCLUSIONS: Rapid intraoperative tissue expansion with a Foley catheter is a means of providing increased tissue area for reconstructive surgery of the eyelids and periorbital region. This technique provides excellent tissue match for color, texture, and thickness. The technique decreases the size of the incised and undermined skin-muscle flap and the tension needed for wound closure.

Aged↗

PubMed1994

Effect of flicker on macular blood flow assessed by the blue field simulation technique.

PURPOSE: To determine the effect of diffuse luminance flicker on the motion of leukocytes in the retinal macular capillaries of normal subjects. METHODS: Using the blue field simulation technique, subjects were asked to match the motion of simulated leukocytes displayed on a video monitor to that of their own entoptically seen white blood cells (WBCs). The changes in velocity and density of the WBCs were recorded after stimulation with diffuse luminance flicker of various durations (0 to 16 seconds), either immediately or at various delays (2, 4, 8 seconds) after cessation of the stimulus. RESULTS: White blood cell velocity increased as flicker duration increased from 0 to 16 seconds. After cessation of flicker, leukocyte motion decreased to baseline within 15 seconds. CONCLUSIONS: The authors' findings suggest a coupling between retinal neural activity and blood flow in the macular region of the retina. The rapidity of both the flicker-induced increase in WBC motion and the disappearance of the effect after flicker cessation resembles the time course of blood flow changes previously observed in the microcirculation of the cat optic nerve.

Adolescent↗