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R Flom

Publications and source records attributed to R Flom.

6 recordsLinked to original sources
PubMed2001

A comparison of two methods of evaluating cornea-to-contact lens base curve fluorescein patterns in keratoconus.

PURPOSE: The purposes of the study were as follows: (1) to compare the apical fitting relationship of habitual contact lens fluorescein patterns in keratoconus as determined by clinician assessment of on-eye patterns to those determined by photograph readers looking at slides of fluorescein patterns and (2) to determine the validity of the techniques used in assessing the apical fitting relationships of rigid corneal contact lenses on keratoconic corneas. METHODS: Central fluorescein patterns of rigid contact lens-wearing keratoconus patients enrolled in the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study were graded as "definite touch," "touch," "clearance," or "definite clearance" by certified clinicians. Photographs of these patterns were evaluated independently by certified, masked photograph readers using the same grading scale. RESULTS: Agreement between "re-reads" of the same fluorescein pattern slides by the photograph readers was substantial (weighted kappa = 0.751). Agreement between assessments of habitual fit fluorescein patterns at the baseline vs. the repeat visits was poor for the photograph readers (weighted kappa = 0.254) and moderate for the clinicians (kappa = 0.480). Agreement between clinicians' and photograph readers' assessment of the habitual contact lens fluorescein pattern at the baseline visit was fair (weighted kappa = 0.382). CONCLUSIONS: Repeatability and validity of this technique were fair to excellent. Many factors influence fluorescein pattern interpretation, and improvement of the objective method of fluorescein pattern assessment by photograph readers will require improved methodology that takes these factors into consideration.

Contact Lenses↗
PubMed1993

False aneurysm associated with rupture of an arteriovenous malformation--implications for treatment: case report.

The morphological features associated with cerebral arteriovenous malformations have been under increasing scrutiny since the advent of high-definition and superselective angiography; certain features may be associated with an increased risk of rupture. In the systemic circulation, the presence of a false aneurysm after the rupture of a vessel has been described; however, no similar phenomenon has been reported in the cerebral circulation. In this case report, we describe a false aneurysm in a young man who had an arteriovenous malformation that hemorrhaged in the posterior fossa. Computed tomography and magnetic resonance imaging revealed a posterior fossa hematoma in the lower brain stem and cerebellum. Angiography indicated that the arteriovenous malformation was fed primarily by the left posterior inferior cerebellar artery. The mass effect of the hematoma was visible as a hypodense region. In the middle of the hematoma, on the distal portion of the posterior inferior cerebellar artery, was a dilatation, measuring 4 x 5 mm, with a stagnation of the contrast medium that was pathologically consistent with a false aneurysm. The patient with a false aneurysm, such as the man we describe, runs a significant risk of hemorrhage at the time of resection of the arteriovenous malformation, with additional implications for endovascular treatment. The volume of embolic injections of the involved vessel should be limited to avoid raising the intra-arterial pressure, and the choice of embolic material must be tailored individually. Recognizing the presence of false aneurysm is important in the choice and timing of therapy.

Adult↗
PubMed1989

Corneal hydration control in Fuchs' dystrophy.

Corneal hydration control was tested in 22 patients with Fuchs' dystrophy, and eight subjects of similar age without the disease, by measuring the corneal thickness recovery from swelling induced by hypoxia or following overnight sleep. Measurement precision was enhanced by using a modified optical pachometer and conducting two test procedures which were analyzed by a coupled exponential model. We have identified three parameters of the recovery from corneal swelling which may be used to describe hydration control: percent recovery per hour (PRPH) (mean 25.4% for Fuchs' and 34.2% for normals), time for 95% of corneal thickness recovery (mean 10.2 hr for Fuchs' and 7.1 hr for normals), and the open-eye steady-state thickness (mean 562 microns for Fuchs' and 537 microns for normals.) A PRPH of 17.1%/hr was identified as the minimum below which the cornea could not regain its open-eye steady state during the entire day and approaches decompensation. Our test procedure quantifies the corneal hydration control mechanism and may provide a test of endothelial function which can be used to monitor the progression of Fuchs' disease and guide decisions related to corneal surgery.

Aged↗
PubMed1989

Age differences in corneal hydration control.

Dynamic changes in corneal thickness were measured in eight young and eight older normal subjects (mean ages 24.4 +/- 4.3 years and 71.9 +/- 7.3 years, respectively) to provide data for quantitative assessment of corneal hydration control and thereby provide information for studying age differences in this important aspect of corneal function. For each subject, pachometry data were obtained by (A) monitoring corneal recovery following hypoxic stress, and by either (B1) measuring recovery after sleep or (B2) by measuring corneal thickness in the late afternoon. The combined data from A and B1 or A and B2 were analyzed through an exponential model to provide information on the: (1) percent recovery per hour (PRPH) following induced corneal hydration; (2) open-eye steady-state (OESS) corneal thickness; (3) residual corneal swelling just before the hypoxic stress test; (4) amount of corneal edema induced by hypoxic stress; and (5) time to reach 95% recovery back to the OESS thickness level (T95%). The results show that between the two age groups, there are substantial differences in some characteristics of corneal hydration while other aspects are similar. For example, the mean PRPH values (58.9 +/- 7.8% and 34.2 +/- 6.4%/hr) were significantly higher in the younger subjects (P = 0.0002) and the mean time for 95% recovery to OESS thickness (207 +/- 42 min and 452 +/- 117 min) was significantly lower in the younger vs. the older group (P = 0.0002).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗