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Ultrasound Biomicroscopy

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					ULTRASOUND BIOMICROSCOPY

                        Essay
Submitted for the partial fulfillment of Master Degree in
                   Ophthalmology

                          By
                Hanaa Hamdi Rashad
                   M.B.,B.Ch
    Faculty of Medicine,Ain Shams University

                    Supervised by
     Prof.Dr./Mahmoud Hamdi Ibrahim
           Professor of Ophthalmology
    Faculty of Medicine,Ain shams University

                 Dr./Dina Ezzat
            Lecturer of Opthalmology
    Faculty of Medicine, Ain shams University


                Faculty of Medicine
               Ain Shams University
                       Cairo
                       2007
                       Ultrasound Biomicroscopy
      Imaging of the eye and orbit is facilitated by the use of ophthalmic
ultrasound (5-10MHz).Palvin , etal (1990) developed the high frequency
(50-100MHz) biomicroscopic ultrasound) , using the high frequency
transducters to provide high resolution in vivo imaging of the anterior
segment - .Ultasound biomicroscopy (UBM) is a high resolution , non
invasive high frequency ultrasound ( HFU) technique that allows
assessment of the anterior segment and peripheral retina ( Garcia - Feijoo,
etal , 2003 ) .


    The UBM technology is based on incorporation of 50-100 MHz
transducers in a β mode echography clinical scanner . Different transducer
frequencies can be used depending on the ocular tissue to be imaged . In
general , increasing the transducer frequency improves the image resolution
but limits the depth of tissue penetration , so may be useful in refractive
surgery Conversely a decrease in transducer frequency increases the
penetration depth but decreases tissue resolution . Tissue penetration is
approximately 4 – 5 mm and the scanner produces a 5× 5mm field with 256

vertical imaged lines ( or A – Scans ) at a scan rate of eight frames per
second . Palvin etal (1991) describe and quantify the normal values for
anterior segment quantitative assessment of its relationships


 UBM is a new ultrasound diagnostic procedure that provides high
definition image of the anterior segment including retroirideal structure and
the angle region . The structures surrounding the posterior chamber ,
including the ciliary body , iridolenticular relation-ship and zonular
apparatus of zinn , previously hidden from clinical observation , can be
imaged and their normal anatomic relation –ship assessed (Tello etal, 2000)
.


        UBM is independent on the clarity of the optical media . In cases
with corneal opacity visualization of the anterior chamber and gonioscopy
becomes unfeasible , ( Abd El- Razek etal , 2006 ).




UBM is a useful tool for evaluating patients with anterior segment
problems like glaucoma including congenital type as it can demonstrate
associated congenital anomalies and differentiating different functional and
type of primary congenital glaucoma . ( Attia etal ;2004 )


     UBM measurements of the anterior chamber depth as well as ciliary
body surface area is beneficial in evaluation of accommodative intra -
ocular lens (Hofy etal ;2006)




    Aim of work
The aim of our work is to demonstrate UBM diagnostic values in anterior
segment different pathology .
References
1 – Abd El – Razek – R , El- Katib – A , El – Essawy – R and Metwaly _M . In "

UBM in congenital glaucoma : what information can it provide? " .Bull .ophthalmol .

Soc . EGYPT , 2006 ; vol. 99 , Number 6 , P.873 – 879 .



2 – Attia – HE , El –cheweich – HM , El – Basty – MK and El –Kady – SK . In "

UBM evaluation of trabeculectomy filtering blebs with and without mitomycin "

.Bull .ophthalmol . Soc .EGYPT . 2004, vol 97, No . 3, 419 – 424 .



3 – El – Hofy – O , Abou – steit – M , Salah – Y , Hassan – NA , El – Sanabary – Z

and Aseem – M . In " Ultrasound Biomicroscopy in Evaluation of Accommodative

Intra – ocular lens " . Bull . Ophthalmol . Soc . EGYPT , 2006 ; vol 99 , Number 2 , P

.183 – 188



4 – Fayed – AA .In " Traditional Ultrasound graphy and UBM finding in small size

Eye " . Bull ophthalmol . Soc . EGYPT

        2006 , vol .99,Number 6 .



5– Garcia – Feijoo – J , Jimenez Alfaro – I and Cuina – Sardina – R . In " Ultrasound

biomicroscopy examination of posterior chamber phakic intraocular lens position " .

ophthalmology . 2003;110:163 – 172 .



6– Hanafy _ M . In " Assessment of limbal lesions by Ultrasound Biomicroscopy (

UBM )' . Bull . Ophthalmol . Soc . EGYPT , 2001 , vol . 94 , Number 1 , 55 -62 .
7 - Palvin – CJ , Harasiewicz –K and Sherar – MD . In " clinical use of ultrasound

biomicroscopy " .Ophthalmology . 98 : 287 – 295 , 1991 .



8 – Palvin – CJ , Sherar – MD and Foster – FS . In " Subsurface ultrasound

microscopic imaging of intact eye " . Ophthalmology, 1990 ; 97; 244 – 250 .



9 – Shalaby – MH and El – Gendy – HA . In " Ultrasound Biomiroscopy ( UBM )

Guided secondary Implantation in Aphakic children ". Bull . Ophthalmol . Soc .

EGYPT , 2006 , vol 99 , Number 6 , P.913 – 919 .




10 – Tello –C , Rothman – R , Ishikawa – H and Ritch – R . In " Differential

Diagnosis of the angle closure glauco ma". ophthalmology clinics of North America ;

volume 13 , No 3 , 2000 .




plane of the work :

1-Introduction:

               A -Ultrasonograghy in general.
              B- History of ultrasound biomicroscopy (UBM).

2-Physical properties.

3-Discription of the apparatus.

4-Mode of the use (Methods of examination).

5-Clinical applications and benefits in the :

              A-Cornea.

              B-Anterior chamber.

              C-Angle of the anterior chamber.

              D- Ciliary body.

              E-Posterior chamber.

              F-Surgeries of glaucoma.

             G-Crytalline lens.

             H-Intra-ocular lens surgeries.

				
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