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Biomedical subjects

R Ritch

Publications and source records attributed to R Ritch.

259 records · Page 15Linked to original sources
PubMedDate not supplied

A technique for performing ultrasound biomicroscopy in the sitting and prone positions.

To develop a reliable method for performing ultrasound biomicroscopy (UBM) in the sitting and prone positions. The probe suspended from an articulated arm was removed and reattached to the arm upside-down for use in the prone position and horizontally for use in the sitting position. A latex Tono-Pen tip cover was attached to the edge of the eyecup and was placed over the transducer through the small hole on the tip of the Tono-Pen tip cover. UBM was successfully performed in the prone and sitting positions with no loss of image quality. This method can expand the ability of the UBM to examine alterations in anatomic relationships among anterior segment structures between the supine, sitting, and prone positions.

Anterior Eye Segment↗
PubMedDate not supplied

Grayscale and proportion-corrected optical coherence tomography images.

BACKGROUND AND OBJECTIVE: The commercially available optical coherence tomography (OCT) scanner displays images in a pre-set window regardless of the projected scan length on the retinal surface. The aim of this study was to demonstrate the true dimensions of proportion-corrected OCT images and the additional information present in grayscale images. MATERIALS AND METHODS: OCT raw data were exported to an IBM-compatible PC and processed to show grayscale and proportion-corrected images using an automated software of our own design. RESULTS: Eyes with cystoid macular edema and retinal pigment detachment were analyzed. Grayscale images showed a finer gradation of signal reflectance. Scan lengths of 2, 4, 6, and 8 mm on the retinal surface showed different qualitative appearances using proportion-corrected software from the printed or on-screen images. CONCLUSIONS: Grayscale OCT images can be used to demonstrate additional information not present in false-color images. The disparity between the standard OCT image format and proportion-corrected images emphasizes the need for quantitative rather than qualitative evaluation of retinal dimensions and internal reflectance.

Algorithms↗
PubMedDate not supplied

Inadvertent corneal indentation can cause artifactitious widening of the iridocorneal angle on ultrasound biomicroscopy.

A 70-year-old Asian female with narrow angles underwent ultrasound biomicroscopy (UBM) darkroom provocative testing. The angle was narrow under light conditions and occluded in the dark, except for the inferior quadrant where the angle was wide and the iris concave. This was reproducible in four quadrants with the use of a small UBM eye cup but not the large one. A small eye cup can indent the cornea, resulting in artifactitious angle widenening. Care must be taken when using the small eye cup not to press on the cornea.

Adult↗
PubMedDate not supplied

The use of scleral transillumination to localized the extent of a cyclodialysis cleft.

Several techniques have been described to localize and repair cyclodialysis clefts. We describe a technique that may be used to easily and accurately localize a cyclodialysis cleft using scleral transillumination. We have verified the accuracy of this technique using high frequency ultrasound biomicroscopy. The location of the cleft was verified using high frequency ultrasound biomicroscopy. Scleral transillumination may facilitate the accurate location of cyclodialysis and may be a useful adjunct in planning the surgical repair of a cyclodialysis cleft.

Adolescent↗