Verifying complaints of difficulties in night vision using electroretinography and dark adaptation tests.

PURPOSE: To determine the electroretinographical and psychophysical parameters that can help to verify patients' complaints of reduced night vision. METHODS: We tested 275 consecutive patients with normal appearing fundi, complaining of visual difficulties at night, using flash electroretinography (ERG) and dark adaptation (DA) test. Two ERG parameters were used to assess a scotopic retinal function: the amplitude of the response to dim blue flash (the rod response) and the b-wave ratio (measured/expected). Dark adaptation was measured with green- and red-light stimuli after exposure to a bright, bleaching light. The psychophysical parameter of night vision was defined as the threshold for detection of the blue-green stimulus that was measured after 40-45 min in complete darkness. RESULTS: Fifty-five patients were excluded from the analysis because of a discrepancy between the two ERG parameters in assessment of scotopic retinal function. The remaining 220 patients were divided into 4 groups: (1) normal ERG and normal DA, (2) subnormal ERG and subnormal DA, (3) normal ERG and subnormal DA and (4) subnormal ERG and normal DA. The ERG and DA tests supported the complaint of visual difficulties at night in 67 patients (group 2), while 34 patients were characterized as having normal scotopic visual function (group 1). The other 119 patients (groups 3 and 4) presented a diagnostic dilemma because one test (ERG or dark adaptation) showed normal scotopic function, while the other indicated subnormal scotopic function. CONCLUSION: Our findings indicate that ERG is an essential, but not sufficient test for verifying patient's complaint on visual difficulties in the dark. We suggest using both electroretinography and psychophysical dark adaptation to test patients complaining of reduced night vision.

Achieving the Recommended Gestational Weight Gain in High-Risk Versus Low-Risk Pregnancies.

BACKGROUND: Abnormal gestational weight gain (GWG) has been associated with adverse outcomes for mothers and their offspring. OBJECTIVES: To compare the achievement of recommended GWG and lifestyle factors in women with high-risk versus normal-risk pregnancies. METHODS: Pregnant women hospitalized in a gynecological and obstetrics department and pregnant women who arrived at a community clinic for a routine checkup were interviewed and completed questionnaires relating to weight gain and lifestyle factors (e.g., smoking, diet, exercise). Recommended GWG was defined by the American Congress of Obstetricians and Gynecologists (ACOG). RESULTS: GWG higher than ACOG recommendations was reported by 52/92 women (57%) with normal pregnancies and by 43/86 (50%) with high-risk pregnancies. On univariate analysis, characteristics associated with greater GWG were: current or past smoking, age > 40 years, pre-gestational body mass index (BMI) > 25 kg/m2, low fruit intake, and high snack intake. High-risk pregnancies were associated with pre-gestational BMI > 25 kg/m2 (48% vs. 27%, P = 0.012), consumption of vitamins (84% vs. 63%, P = 0.001), avoidance of certain foods (54% vs. 21%, P = 0.015), receiving professional nutritionist consultation (65% vs. 11%, P = 0.001), and less physical activity (9% vs. 24%, P = 0.01). CONCLUSIONS: A minority of pregnant women met the recommended GWG. No difference was noted between normal and high-risk pregnancies. High-risk population tended to have a less healthy lifestyle. Counseling to follow a healthy, balanced diet should be recommended, regardless of pregnancy risk, with particular attention to women at high risk of extra weight gain.