الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Gonioscopy is the standard method in assessment the anterior chamber angle, the most available method and the most method which is widely used, but gonioscopy is not without disadvantages, it is a cumbersome method especially in busy clinics. Needs contact to the eye which can affect the measurements with inadvertent pressure which can change the angle measurement.
Gonioscopy is a semi quantitative method using different grading systems, like Shaffer and Spaeth grading system, which is the most accepted and widely used methods of grading system.
But even experienced, cross-trained examiners have only moderate agreement in determining angle width.
The disadvantages which can be overcame using the new modalities of the anterior chamber assessment like AS-OCT.
Assessment of the angle using the AS-OCT can be done easily without contact to the eye. And can produce quantitative measurements of the angle using a lot of parameters. Like angle open distance 500(AOD 500), angle recess area (ARA 500),trabecular iris space area (TISA).the parameters which can be carried on easily using the high resolution images produced by the AS-OCT.
Testing the reliability of the AS-OCT measurements comparing to the gonioscopy measurements which we have used as a reference method, showed a good agreement between the two methods and even the disagreement between the two method can be hypnotized to the difference in the technique of the two methods, gonioscopy can produce pressure on the cornea which can change the measurements ,and the AS-OCT also with the difficult imaging of the superior and inferior quadrants which need to pull the eye lid up in the superior quadrant, and down in the inferior quadrant.
The measurement of the angle using the AS-OCT is not without disadvantages, as the angle abnormalities can be missed as the device has cross section images and the abnormalities can be missed between those images, but of course with clinical correlation this problem can be overcame. Also the device is expensive and not available in many facilities.
One of the useful parameters of the AS-OCT in angle assessment is the angle open distance 500.the parameter which we have found that it is highly correlated with the angle measurements.
AOD 500 was found to range between 313 to 425 micron in grade 3 and 427 to 576 micron in grade four.
Of course all the parameters of the AS-OCT should be tested for the consistency and specificity in larger scale study with larger number of patients.
As previous studies we have noticed that there is no correlation between the angle measurements have no relation with the age, pachymetric measurements and the k values.
Also we have noticed that generally the temporal angles are the larger among the different angles of the eye. and generally males have larger measurements than females.
Gonioscopy up till now is irreplaceable to assess the content of the angle like pigmentations, psudoexofoliation, and new vascularization. This can not be done by the new modalities of the angle assessment.
Anterior segment optical coherence tomography with its rapid, on contact, high resolution image acquisition is a promising tool for the anterior chamber angle assessment