No abstract available.
Ultrasonics

No abstract available.
Ultrasonics*

No abstract available.
Ultrasonics

No abstract available.
Ultrasonics*

Ultrasonic pachymetry was carried out in 300 eyes of normal, myopic, and senile cataract patients with Alcon Surgical Pachymeter. The mean central corneal thickness was 0.527mm+/- 0.034mm. Corneal thickness wa significantly correlated with age, axial length, and sex. No statistical correlation was found between corneal thickness and the right or left eyes, corneal curvature, and ocular tention (within normal range). Pachymetric results were consistent if a good applanation of the probe occurred. Thus, reliable data could only be obtained by skilled user.
Ultrasonics ; Eye

No abstract available.
Lipectomy* ; Ultrasonics*

No abstract available.
Osteotomy ; Ultrasonics

It is well documented that increased corneal thickness leads to artificially high estimations of intraocular pressure(IOP) measured with applanation tonometer. To evaluate the influence of central corneal thickness on IOPs measured with non-contact tonometer and Goldmann applanation tonometer and on the IOP discrepancies between two tonometer according to corneal thickness, the IOPs and central corneal thickness of 96 eyes of 48 persons who visited to have their high IOPs evaluated were measured with Goldmann applanation tonometer, non-contact tonometr(CT-50, Topcon, Japan), and corneal pachometer(Humphrey ultrasonic pachometer-850). IOPs measured with each tonometer showed statistically significant linear correlation(p<0.001), IOP rises as the corneal thickness increases(p<0.001), IOPs measured with non-contact tonometer were higher than those measured with Goldmann applanation tonometer(p<0.001), but there were no significant differences between the IOP discrepancies of each tonometer according to corneal thickness, and between the IOP and age in a consistant corneal thickness(p>0.1). In conclusion, the central corneal thickness must be considered in estimating IOP and the IOP differences measured with Goldmann applanation tonometer and non-contact tonometer were not statistifically significantly increased as the corneal thickness increased.
Humans ; Intraocular Pressure* ; Ultrasonics

PURPOSE: To evaluate the effect of dry eye on the corneal thickness measured by Orbscan and ultrasonic pachymetry. METHODS: The central corneal thickness was measured by both ultrasonic and Orbscan pachymetry in 30 eyes with dry eye (dry eye group) and in 30 eyes of normal subjects (control group). Dry eye was diagnosed when a Schirmer test result was less than 10 mm (after topical anesthesia) and the test for tear osmolarity was also performed. RESULTS: Tear osmolarity was 364.4+/-42.9 mOsm/L in dry eye group and 337.8+/-34.5 mOsm/L in control group. It was significantly higher in dry eye group than in the control group (p=0.011). Mean central corneal thickness measured by Orbscan pachymetry was 547.5+/-27.3 microgram in dry eye group and 562.0+/-20.4 microgram in the control group. It was significantly thinner in dry eye group than in the control group (p=0.023). Mean central corneal thickness measured by ultrasonic pachymetry was 535.7+/-27.2 microgram in dry eye group and 547.6+/-20.1 microgram in the control group with out significant difference between the two groups (p=0.059). CONCLUSIONS: The corneal thickness measured by ultrasonic pachymetry is less affected by dry eye compared to that measured by Orbscan pachymetry.
Osmolar Concentration ; Ultrasonics*

This article describes the design and development of an ultrasonic power meter which is consist of an electronic balance, a practice target, an acoustic enclosures and a blocking. The electronic balance mounted on the blocking is linked with the practice target by connecting rod. By adjusting the blocking makes the practice target suspended above ultrasound probe, and then the ultrasonic power can be measured. After initial tests, the ultrasonic power meter performanced with good stability and high precision.
Equipment Design ; Ultrasonics