Quantitative ultrasound at the hand phalanges in subjects with poor visual acuity

The aim of the study was an assessment of skeletal status in a group of subjects with impaired vision.

91 subjects with poor visual acuity (44 males, mean age: 61.4 +/- 10.9 years and 47 females, mean age: 61.3 +/- 16.8 years) were evaluated and compared with age-matched normal, healthy population (230 males and 964 females). Patients were recruited from members of Polish Blind Association and subjects living in a nursing home. In both patients and controls any reasons (medications or diseases) known to affect bone metabolism were not present. Skeletal status was assessed using the DBM Sonic 1200 (IGEA, Carpi, Italy) which measures amplitude-dependent speed of sound (Ad-SoS, m/s) at the hand phalanges. Binocular visual acuity was established using a Snellen chart.

Mean binocular visual acuity was in males 0.09 +/- 0.14 and in females 0.179 +/- 0.2 and was significantly lower in males (P < 0.01). Place of stay (community or nursing home), previous fractures, and kind of work did not affect skeletal measurements. Ad-SoS, T-score, and Z-score in male patients were 1993 +/- 74 m/s, -1.89 +/- 1.05, and -0.97 +/- 1.03, respectively and were significantly higher than in male controls (1968 +/- 69 m/s, -2.25 +/- 0.99, and -1.29 +/- 0.92; P < 0.05. Ad-SoS, T-score, and Z-score in female patients were 1946 +/- 103 m/s, -2.54 +/- 1.5, and -0.7 +/- 1.05, respectively and did not differ significantly in comparison with data in control females (1946 +/- 75 m/s, -2.54 +/- 1.07, and -0.6 +/- 0.78). In both genders visual acuity did not correlate with Ad-SoS values.

The association between poor visual acuity and skeletal status assessed by quantitative ultrasound (QUS) is dependent on gender and in females does not differ from controls; in males ultrasound parameter measured is even significantly higher than in male controls.