retinoscope, optom faslu muhammed

24
RETINOSCOPY OPTOM FASLU MUHAMMED

Upload: faslu-muhammed

Post on 14-Feb-2017

54 views

Category:

Healthcare


1 download

TRANSCRIPT

Page 1: Retinoscope, optom faslu muhammed

RETINOSCOPY OPTOM FASLU MUHAMMED

Page 2: Retinoscope, optom faslu muhammed

It’s a method to evaluate the refractive error of an eye objectively by utilizing the technique of neutralization.

We evaluate the eye as an optical instrument, ignoring any information the eye transmit to the brain. Retinoscopy does not depend on the patient’s vision or judgment.

Page 3: Retinoscope, optom faslu muhammed

PRINCIPLE It is based on the fact that when light is

reflected from mirror in to the eye the direction in which the light will travel across the pupil will depend up on the refractive state of the eye.

Bring pts FP to retinoscope peep hole. Emmetropia:infinity hyperopia:beyound infinity Myopia:less than infinity

Page 4: Retinoscope, optom faslu muhammed

The first objective diagnosis of refractive error was by French Ophthalmologist “F. Cuignut”

“Father of Retinoscopy”

Page 5: Retinoscope, optom faslu muhammed

Jack C. Copeland, the father of Streak Retinoscope, who developed the Retinoscope and spent his life teaching its use”

Page 6: Retinoscope, optom faslu muhammed

EVOLUTION

Skiascopy Dioptroscopy Pupilloscopy Korescopy Umbrascopy Scotoscopy

Page 7: Retinoscope, optom faslu muhammed

Types Of Retinoscope:A)Reflecting(mirror) retinoscopes:

*Cheap & the most commonly employed

*A source of light is required,which is kept above & behind the head of the patient.

*The source of light used should be small,bright & enclosed.

*A mirror retinoscope may consist of a single plane mirror or a combination of plane and concave mirrors(Priestley-Smith’s mirror)

Page 8: Retinoscope, optom faslu muhammed

A BMirror retinoscopes: A)Plane mirror; B)Priestley-smith’s mirror

Page 9: Retinoscope, optom faslu muhammed

*The central aperture in the mirror should be 3-4mm in diameter so that a sufficient amount of light can enter the observer’s eye.

Page 10: Retinoscope, optom faslu muhammed

B)Self-illuminated retinoscopes:*Costly but handy*2 types: (i)a spot retinoscope (ii)a streak retinoscope

(ii)a.Heine streak retinoscope b.Welch allen streak retinoscope

(i)A spot retinoscope

Page 11: Retinoscope, optom faslu muhammed

Spot retinoscopes:*It consists of a bulb with a tiny wired filament about 1-2 mm in size.

Page 12: Retinoscope, optom faslu muhammed

Streak retinoscopes: In streak retinoscope the illumination is

provided by a special bulb that has a straight filament.

It is more sensitive than spot retinoscope in detecting astigmatism. It is provided by a special bulb that a straight filament,thus forming a ‘streak’ in projection.

Page 13: Retinoscope, optom faslu muhammed

SURFACE ANATOMY

Page 14: Retinoscope, optom faslu muhammed

PROJECTION SYSTEM

Page 15: Retinoscope, optom faslu muhammed

PROJECTION SYSTEM

Page 16: Retinoscope, optom faslu muhammed

OBSERVATION SYSTEM

Page 17: Retinoscope, optom faslu muhammed

PREREQUISITES FOR RETINOSCOPY 1. dark room 2.Trial set 3.Trial frame 4.Phoropter/refractor 5.Distance target 6.Retinoscope

Page 18: Retinoscope, optom faslu muhammed

PROCEDURE Patient is made to sit at a distance of 1m,67 cm,

50 cm.. from the examiner. With the help of a retinoscope, light is thrown onto

the patient’s eye. Who is instructed to look at a farpoint (to relax

accommodation).

Page 19: Retinoscope, optom faslu muhammed

Through the hole of retinoscope , the examiner observes a red reflex in the pupillary area of the patient.

Move the retinoscope in horizontal and vertical meridia.

Neutralise the reflex

Page 20: Retinoscope, optom faslu muhammed
Page 21: Retinoscope, optom faslu muhammed

THE CHARACTERISTICS OF THE MOVING RETINAL REFLEX ARE AS FOLLOWS:

Speed and brilliance. Width of reflex. In the presence of astigmatism.

Page 22: Retinoscope, optom faslu muhammed
Page 23: Retinoscope, optom faslu muhammed

STATIC VERSUS DYNAMIC RETINOSCOPY Static:procedure performed without active

use of accommodation Dynamic:with active use of accommodation

Page 24: Retinoscope, optom faslu muhammed

Thank you