الفهرس 
Introduction and Aim of the WorkOnly 14 pages are availabe for public view
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Abstract
SUMMARY
The term ultrasound biomicroscopy (UBM) have been applied to this new imaging technique because of similarities to optical biomicroscopy, i.e., the observation of living tissue at microscopic resolution. It is a nonspecific imaging technique that can be used for any ocular pathology which falls within its penetration limits.
A basic introduction to ultrasound and its propagation in tissue has been presented. The wave nature of ultrasound is similar, in many respects, to optical radiation, in that it obeys the fundamental laws of reflection and refraction. This means that it is possible to focus ultrasound to achieve beam widths 20 to 80rum in the frequency range from 50 to 100 MHz.
This is approximately 10 times the resolution achieved at conventional ophthalmic ultrasound imaging frequencies, because losses due to attenuation increase almost linearly with frequency, the total imaging depth is significantly reduced, leading to field of view of 4-5 mm. It is necessary to have knowledge’ of the nOlmal appearance of ocular anatomical stmctures as imaged by UBM before pathological conditions can be analyzed.
UBM provides a view of subsurface structures In their normal relationships without the distortion that occurs with preparation of histological specimens. It is useful to define a series of measurement parameters by UBM that can be used for nlture comparison between normal
and pathological conditions, and define measurement sites in term of fixed anatomical landmarks such as the scleral spur.
UBM provides a new way of assessing corneal edema and leucomas that allows objective differentiation and measurement of the corneal stroma and epithelium. It provides a new method for assessing the accuracy of graft
rlacement, and imaging underlying changes prior to surgery in eyes with corneal opacification. UBM also holds prom{se as a method of monitoring the results of various types of refractive surgery. It is used to study the of keratoconus, to determine corneal thickness and
UBM is used as an adding method in detecting the different etiologies of glaucoma, Plateau iris syndrome, suprachoroidal effusion, malignant glaucoma and pigmentary glaucoma are just examples for which useful information has been gained by using this tool, in addition to its value in postoperative secondary glaucoma, after vitreoretinal surgery and congenital cataract surgery, in addition to its value after different glaucoma surgeries.
Intraocular lenses (lOLs) are easily outlined with UBM because of the high reflectivity of the IOL material. UBM presents the unique ability to image and locate the position of the haptics and its relation to the surrounding stmctures. The surgeon can use this knowledge to monitor and refme surgical techniques. UBM also allows analysis of surgical complications and provides new insight into their etiology.
UBM adds a new information of imaging the anterior segement tumors, morphological and internal reflectivity patterns aid in differential diagnoses. UBM is diagnostic hi differentiating cysts from solid tumors. It is also useful in detecting tumors changes and borders that aid hi the treatment planning. UBM is an interesting instrument for the assessment of patients with intermediate uveitis.