Biomedical subjects

R Choe

Publications and source records attributed to R Choe.

3 recordsLinked to original sources

PubMed2001

Optic disk characteristics before the occurrence of disk hemorrhage in glaucoma patients.

PURPOSE: To evaluate qualitatively the structural characteristics and the associated features that antedate the occurrence of a disk hemorrhage in patients with glaucoma. METHODS: Retrospective observational case series. A total of 4018 pairs of stereoscopic optic disk images obtained over 15 years were reviewed. All eyes with optic disk images before the occurrence of a disk hemorrhage were enrolled. The disk images were evaluated in a masked fashion with respect to the general neural rim and peripapillary appearance. RESULTS: The optic disk characteristics and associated features that most antedate the disk hemorrhage in 33 eyes of 26 patients that had previous optic disk images for evaluation are focal neural rim notch (36%), thin sloping rim (42%), peripapillary atrophy (79%), and superior-inferior rim asymmetry (73%). In eyes with preexisting focal rim notches, all subsequent disk hemorrhages were identified at or adjacent to the notches. CONCLUSIONS: Focal rim notching may precede the occurrence of a disk hemorrhage.

Aged↗

PubMed2000

Paired parallel locking forceps.

We describe an instrument used to prevent contact between an antimetabolite and the conjunctiva-Tenon's wound edge in filtering surgery. Paired parallel locking forceps were used to keep the everted conjunctival-Tenon's wound edge from touching the antimetabolite sponge during limbal-based filtering surgery while enabling manipulation of the antimetabolite sponge. This allows the surgeon to more easily avoid the conjunctival edge, making antimetabolite touch easier and safer.

Alkylating Agents↗

PubMed2000

Modeling photon transport in transabdominal fetal oximetry.

The possibility of optical oximetry of the blood in the fetal brain measured across the maternal abdomen just prior to birth is under investigation. Such measurements could detect fetal distress prior to birth and aid in the clinical decision regarding Cesarean section. This paper uses a perturbation method to model photon transport through an 8-cm-diam fetal brain located at a constant 2.5 cm below a curved maternal abdominal surface with an air/tissue boundary. In the simulation, a near-infrared light source delivers light to the abdomen and a detector is positioned up to 10 cm from the source along the arc of the abdominal surface. The light transport [W/cm2 fluence rate per W incident power] collected at the 10 cm position is Tm = 2.2 x 10(-6) cm(-2) if the fetal brain has the same optical properties as the mother and Tf = 1.0 x 10(-6) cm(-2) for an optically perturbing fetal brain with typical brain optical properties. The perturbation P=(Tf - Tm)/Tm is -53% due to the fetal brain. The model illustrates the challenge and feasibility of transabdominal oximetry of the fetal brain.

Abdomen↗