ABSTRACT
Background Measurement of ciliary sulcus distance is important for phakic intraocular lens implantation.Suowei panoramic 50-MHz digital ultrasound biomicroscopy makes it possible for the direct measurement of ciliary sulcus distance.Objective The aim of this study was to investigate the correlation between anterior chamber(AC)angle diameter and ciliary sulcus distance in different AC depth population and offer a clinical guide.Methods The anterior chamber angle diameter and ciliary sulcus distance were measured in 30 right eyes with shallow anterior chamber caused by suspect glaucoma and 30 right eyes with deep anterior chamber dut to the high myopia with Suowei panoramic 50-MHz digital ultrasound biomicroscopy.Three horizontal B-scans with the focal plane approximately at a depth corresponding to the iris plane were acquired for each eye.The differences of the anterior chamber angle diameter and ciliary sulcus distance were calculated and compared between the two groups.The correlation of the anterior chamber angle diameter and ciliary sulcus distance were evaluated in respective group.Results In shallow AC group,the mean angle diameter was(11.49+0.75)mm,the mean ciliary sulcus distance was (10.97±0.86)mm with the mean standard deviation of the difference of(-5.14± 0.55)mm,showing a statistically significant difference(t =-5.092,P =0.000).In shallow AC group,linear regression analysis showed a statistically significant correlation between ciliary sulcus distance and angle diameter(R2=0.593,P=0.000)and the Pearson's correlation coefficient was 0.767.In deep AC group,the angle diameter was(12.69±0.67)mm;while ciliary sulcus distance was(12.31 ± 0.61)mm with the mean slandard deviation(-0.38 ± 0.17)mm,which was statistically significantly different(t=-5.531,P=0.000).The ciliary sulcus distance was found to be linear correlation with the angle diameter(R2 =0.699,P=0.000)and Pearson' s correlation coefficient of 0.836.Conclusions Panoramic ultrasound biomicroscopy is an useful tool to the measurement of ciliary sulcus distance.This study exhibited that the ciliary sulcus distance is significant associated with the anterior chamber angle diameter,which may offer a guide for phakic intraocular lens implantation.
ABSTRACT
<p><b>BACKGROUND</b>Measurement of anterior segment parameters plays an important role in diagnosis and treatment of glaucoma. The objective of this study was to evaluate the repeatability and reproducibility of anterior chamber volume (ACV) measurements with rotating scheimpflug camera (RSC) and to examine agreement with anterior segment optical coherence tomography (AS-OCT).</p><p><b>METHODS</b>Thirty nine healthy normal subjects were recruited from the Eye Center of Tongren Hospital. ACV was measured using RSC and AS-OCT in a randomly selected eye for each subject. For RSC measurements, both automatic and manual ACV measurements and 2 independent operators' ACV measurements were obtained. All subjects were invited for 3 visits within a week to evaluate repeatability and reproducibility of ACV measurement by RSC. Agreement was evaluated between RSC and AS-OCT.</p><p><b>RESULTS</b>Good repeatability and reproducibility were found for both automatic and manual ACV measurements obtained by RSC. For intrasession repeatability, coefficient of variation (CVw) and intraclass correlation coefficient (ICC) values for automatic were 3.52% and 0.98; the values for manual were 3.44% and 0.97, respectively. For intersession reproducibility, the respective CVw and ICC values were 3.96% and 0.96. Good agreement was also found in 2 operators for both automatic and manual ACV measurements; nevertheless, poor agreement was found between RSC and AS-OCT (95% confidence interval (CI) for agreement of automatic RSC measurement versus AS-OCT were -96.3 to 72.8 microl and 95% CI for agreement of manual RSC measurement versus AS-OCT were between -41.7 to 10.1 microl).</p><p><b>CONCLUSIONS</b>Both RSC automatic and manual ACV measurements showed good repeatability and reproducibility, and showed comparable agreement between 2 independent operators, but poor agreement was found between RSC and AS-OCT.</p>
Subject(s)
Adult , Female , Humans , Male , Young Adult , Anterior Chamber , Anterior Eye Segment , Cornea , Diagnostic Techniques, Ophthalmological , Glaucoma , Diagnosis , Reproducibility of Results , Tomography, Optical Coherence , MethodsABSTRACT
<p><b>BACKGROUND</b>Phakic intraocular lens (pIOL) implantation has been a popular means for the treatment of high ametropia. Measurements of ciliary sulcus diameter is important for pIOL size determining. But till now, no perfect system can directly measure it. The present study was to evaluate the accuracy, repeatability and reproducibility of direct sulcus diameter measurements obtained by a full-scale 50-megahertz (MHz) ultrasound biomicroscopy (UBM).</p><p><b>METHODS</b>A fresh cadaver human eye with a scale marker inserted through the posterior chamber plane from 3 o'clock to 9 o'clock meridian and 30 randomly selected eyes from 30 normal subjects were scanned by full-scale 50-MHz UBM in horizontal meridional scan plane. The distance between the scales and the whole length of the marker inside the cadaver eye were measured by the same observer using the "built-in" measurement tools and the indicating error of instrument was calculated. Reproducibility of the measurement was evaluated in 30 eyes by 2 operators using Blander and Altman plot test. Repeatability was evaluated from 10 successive eyes randomly selected from the 30 eyes by one operator.</p><p><b>RESULTS</b>On a scale of 1 mm, the greatest indicating error was 40 microm; the mean largest indicating error of 1 mm scale from the 10 images was (26 +/- 14) microm; on a scale of 11 mm, the greatest indicating error was 70 microm; the error rate was 0.64%. The mean length of the needle inside the eye of the 10 images was 11.05 mm, with the mean indicating error of 47 microm, the average error rate was 0.43%. For ciliary sulcus diameter measurements in vivo, the coefficient of variation was 0.38%; the coefficients of repeatability for intra-observer and inter-observer measurements were 1.99% and 2.55%, respectively. The limits of agreement for intra-observer and inter-observer measurement were -0.41 mm to 0.48 mm and -0.59 mm to 0.58 mm, respectively.</p><p><b>CONCLUSION</b>The full-scale 50-MHz UBM can be a high accuracy and good repeatability means for direct measuring the ciliary sulcus diameter and useful for size determining of posterior chamber pIOL.</p>