R D Pardo | PubMed Health

PubMed2000

Reflex lacrimation in patients with glaucoma and healthy control subjects by fluorophotometry.

PURPOSE: Steady state tear turnover (TTO), defined as TTO under normal physiological conditions, is significantly lower in patients with untreated glaucoma than in healthy control subjects. To obtain more information on the effect of glaucoma on lacrimation, a method for quantification of reflex lacrimation was developed and applied to patients with glaucoma or ocular hypertension and healthy control subjects. METHODS: After instillation of 2 microl of fluorescein (2%), the decay of fluorescein concentration in tears was measured by fluorophotometry over 10 minutes to determine steady state TTO. Then, reflex lacrimation was induced by stimulating the trigeminal nerve with ethanol vapor via the nostrils. Thereafter, the decay of fluorescein and corresponding steady state TTO were determined again. An index of reflex lacrimation, defined as the percentage decrease in fluorescein concentration as a result of stimulation, was calculated by forward and backward extrapolation of the steady state decay of the fluorescein concentration in tears, relative to the time of stimulation. RESULTS: The index of reflex lacrimation was determined in 16 patients with newly discovered but not yet treated glaucoma, 16 patients with untreated ocular hypertension, and 16 healthy control subjects. The values did not differ between groups (mean +/- SD, 67.0%+/-17.7%, 63.5%+/-21.3%, and 70.4%+/-19.6%, respectively; ANOVA, P>0.25). Surprisingly, the steady state TTO after stimulation was lower than that before stimulation in each group (ratio, 0.62+/-0.46; paired t-test, P<0.04). CONCLUSIONS: The method developed is appropriate for the quantification of reflex lacrimation. Reflex lacrimation is not influenced significantly by glaucoma or ocular hypertension. The decreased steady state TTO after reflex stimulation may be caused by exhaustion of the lacrimal glands after excessive reflex lacrimation, indicating that normal lacrimation probably also contains reflex tears.

Adult↗

PubMed1996

Stability of walking frames.

Biomechanical tools were used to assess stability for 11 patients who, following the surgical amputation of one lower limb, required the assistance of a walking frame to ambulate. The Walker Tipping Index (WTI), as derived from the forces applied to the walking frame, was developed specifically for this study to examine the relationship between stability and walking frame height during ambulation. However, the WTI may be useful as a criterion of stability to assist clinicians in their evaluation of walker use in a variety of patient populations. Walker stability was examined as subjects, wearing their prostheses, completed 30-sec walking trials in each of the normal, high, and low walking frame height conditions. Adjusting the height of the walker to one setting (3 cm) above or below normal appears to redistribute the load of walking between the upper and lower extremities without adversely affecting stability.

Aged↗

PubMed1993

Walker user risk index. A method for quantifying stability in walker users.

A method for quantifying the stability of a patient using a walking frame is presented. Data collected from a walker-dependent patient recovering from surgical amputation of his right leg were used to demonstrate the derivation and interpretation of a proposed walker user risk index (WURI). WURI curves express risk to the walker user in terms of how much the upper extremities contribute to overall patient support. The WURI analysis of the walker stride presented here quantified the expected clinical impression that this patient was least reliant on the walker immediately after the advance of his prosthetic leg and most reliant when standing on his prosthesis and swinging his nonamputated leg. The analysis also revealed unexpectedly high upper body loads and specific phases in the gait cycle where the patient's balance was at risk.

Accidental Falls↗