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OPHTHALMOLOGY PRACTICE |
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Year : 1993 | Volume
: 41
| Issue : 1 | Page : 37-40 |
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Guidelines for the management of rhegmatogenous retinal detachment
Taraprasad Das
L.V.Prasad Eye Institute, Road No.2, Banjara Hills, Hyderabad 500 034, India
Correspondence Address: Taraprasad Das L.V.Prasad Eye Institute, Road No.2, Banjara Hills, Hyderabad 500 034 India
 Source of Support: None, Conflict of Interest: None  | Check |
PMID: 8225524 
Current techniques of rhegmatogenous retinal detachment repair allow most detachments to be repaired successfully. The success of repair depends on a careful pre-operative examination and choice of an appropriate procedure. The surgery is usually tailored to individual needs. Improvements in surgical techniques coupled with a better understanding of the pathophysiology of rhegmatogenous retinal detachment continue to improve the anatomic and functional success of retinal detachment repair.
How to cite this article: Das T. Guidelines for the management of rhegmatogenous retinal detachment. Indian J Ophthalmol 1993;41:37-40 |
Definition | |  |
Retinal detachments are the results of separation of the sensory retina from the retinal pigment epithelium (RPE). Retinal detachments generally lead to severe visual loss if not successfully treated. Phakic non traumatic retinal detachment occurs in approximately 5 to 12 persons per 100,000 per year.
Etiology | |  |
Rhegmatogenous retinal detachments are caused by a tear or a hole in the retina.The pathogenesis of retinal breaks which cause rhegmatogenous retinal detachments include the development of posterior vitreous detachment (PVD) which may cause retinal break by traction on the retina, or by ocular trauma. Vitreous cavity fluid then passes through the tear causing detachment of the sensory retina from the RPE.
Diagnosis | |  |
The diagnosis of retinal detachment is made on the basis of information obtained from the patient's history and detailec ocular evaluation.
History
Predisposing factors
a. Myopia
b. Lattice degeneration
c. Aphakia
d. Trauma
Symptoms
a. Floaters & Flashes
b. Decrease in vision
c. Constricted visual field
Ocular Evaluation
a. Visual acuity
b. Slit lamp biomicroscopy
c. Applanation tonometry
d. Retinal evaluation
Lattice degeneration is the direct cause of 21% of all retinal detachments and is present in 41% of eyes with detachment. In 55 to 70% of retinal detachments caused by lattice, the detachment is caused by a tear beginning posterior to or atthe end of the lattice degeneration.
Myopes have 42% of all retinal detachments. Myopia with refractive error greater than 8 diopters accounts for 10% of all retinal detachments.
Cataract surgery increases the risk of retinal detachment. Incidence of retinal detachment after intra-capsular cataract extraction (ICCE) is 2 to 5% and after extra-capsular cataract extraction (ECCE) is upto 1.4%. The incidence of retinal detachment in pseudophakic eyes after ECCE is same as without intra ocular lenses. Frequently required capsulotomy partially negates the advantage of ECCE. The incidence of retinal detachment rises upto 3.2% after surgical or YAG capsulotomy.
Management | |  |
The definitive treatment of retinal detachment, once diagnosed, is surgery. The key to successful retinal reattachment surgery is a detailed and careful fundus evaluation by binocular indirect ophthalmoscope with scleral depression and 3 mirror examination of retinal periphery.
During retinal evaluation attention should be paid to
a. Extent of detachment
b. Number, size and location of retinal breaks
c. Peripheral retinal degeneration, particularly lattice
d. Proliferaitve Vitreo Retinopathy changes
Surgery | |  |
In general, retinal detachments are repaired in few days. The presence or absence of macular detachment is the major determinant of the urgency of repair. If the macula is attached the repair should be done as soon as possible, within few hours to maximum a day and if the macula is already detached the repair could be done within few weeks.
Treatment Methods
Retinal reattachment with the use of cryopexy or diathermy in conjunction with scleral buckle, vitrectomy or pneumatic retinopexy are the treatment modalities used for repair of most rhegmatogenous retinal detachments.
Steps of Surgery
There are four basic steps in repairing rhegmatogenous retinal detachment with a scleral buckle. These are :
a. Precise localisation of all the retinal breaks
b. Creation of a chorio-retinal adhesion around the retinal break
c. Placement of scleral buckle to relieve vitreo-retinal traction on the break, and
d. Drainage of subretinal fluid externally or internally
Localisation of the retinal break is done using the indirect ophthalmoscope and the overlying sclera is marked with a marking pen or with the diathermy. Chorio retinal adhesion is created either by trans-scleral cryo or by intra scleral diathermy after scleral dissection. An adequate size and shape of scleral buckle material, either a solid silicone tire or sponge, is sutured to the sclera as an exoplant or as an implant after scleral dissection. The drainage of subretinal fluid, when required is mostly done externally. A radial scratch incision is made on the sclera either under the buckle or outside it, the exposed choroid is cauterized using diathermy and the choroid is perforated using a sharp needle or diathermy electrode. Alternatively, the endo laser tube could be used for external drainage of subretinal fluid. Internal drainage, either through the pre-existing retinal break or through a drainage retinotomy, is done if and when vitrectomy is required in retinal reattachment procedure.
Intra Operative Complications
There are a number of intra operative complications which may compromise the surgical objectives of the retinal detachment repair. These include
a. scleral rupture
b. retinal perforation
c. sub retinal haemorrhage
d. vitreous haemorrhage
e. choroidal detachment
f. retinal incarceration
g. central retinal artery occlusion.
Post Operative Care
1.Patching: The operated eye is patched for one or more days after surgery until the eye is comfortable.
2.Medications: The eye is treated with topical antibiotics, steroids and cycloplegics. The following is the routine schedule: Betamethasone eye drops - I drop 4 to 6 times a day, Gentamicin eye drops - I drop 4 times a day, and Cyclopentolate 1%/ Atropine 1% eye drops - I drop 3 times a day. Gentamicin is discontinued at the end of the second week, Betamethasone is gradually tapered after the second week and cycloplegic is discontinued at the end of four weeks. Systemic antibiotics are rarely necessary.
3.Activity: Ambulation is encouraged as soon as possible. Shaving and bathing below the neck are permitted in a couple of days and full activity is permitted in six weeks time. However, heavy physical activities are not permitted for three months.
4. Follow up schedule : The operated eye is examined daily during the period of hospitalisation and following discharge at the end of second, fourth, sixth and twelfth week. At these evaluations, the status of the retina, position of the retinal breaks, presence of residual subretinal fluid, status of macula and height of the buckle are looked for. The intra ocular pressure and best corrected visual acuity are always measured. The final refraction and change of spectacles is made six to eight weeks after surgery.
Post operative complications | |  |
Simple retinal detachment repair has an overall success rate of 90% with one or more operations. Certain complications may lead to failure of the repair within first few weeks of reattachment procedures ( early post operative complications) while others may appear one or more months later (late operative complications).
Early Complications
a. Persistent detachment
b. Choroidal detachment
c. Glaucoma
d. Buckle exposure/infection
e. Endophthalmitis
f. Symblepheron
g.Anterior segment ischaemia
Late complications
a. Recurrent retinal detachments
b.Proliferative Vitreo Retinopathy
c. Cystoid macular edema
d. Macular pucker
e. Buckle exposure and infection.
Post operative glaucoma in 7%, cystoid macular edema in 25 to 29%, macular pucker in 7 to 9%, anterior segment ischemia in 8% and buckle exposure/infection in 3% of eyes are reported in literature.
Reoperations | |  |
Why?
Persistent retinal detachment or recurrent retinal detachments are due to slow absorption of subretinal fluid, non closure of primary retinal break, new/undetected retinal breaks or due to proliferative vitreo retinopathy changes (PVR). Commonest cause of failure of retinal reattachment surgery is due to PV-R which accounts for upto 25% of all failures.
When?
Reoperation with revision of the scleral buckle is usually required if the retina fails to reattach within 3 to 4 weeks of surgery.
Complex detachments | |  |
The management ofretinal detachments with extensive vitreous opacities or advanced proliferative vitreo retinopathies dc require vitrectomy with long acting gas or silicone oil tamponade with or without scleral buckling. Use of perfluoro carbon liquid (PFCL) is specially recommended in cases of giant retinal tears with detachment and in most traumatic detachments.
The algorithm shows the decision making and management strategies of rhegmatogenous retinal detachment.
Results | |  |
The anatomic and visual success rates of retinal detachment repair have gradually improved over the past decades as a result of:
a. Improved surgical techniques
b. Availability of improved materials
c. Better understanding of the pathophysiology of retinal detachments
Anatomic Success
With the current techniques about 90 % of retinal detachments can be successfully reattached with one or more operations. Eyes with proliferative vitreo retinopathy requiring a retinal detachment repair combined with parsplana vitrectomy have a lower success rate. Similarly retinal detachments with giant retinal breaks have poorer success rates.
Functional Success
The visual results of retinal detachment repair are variable depending on duration of retinal detachment, status of macula, age of the patient and associated features like choroidal detachment and presence of proliferative vitreo retinopathy.
Approximately 40 to 50% of patients regain a visual acuity of 6/15 or better. When the macula is detached, degeneration of photo -receptors may prevent good post operative visual recovery; Seventy five percent of patients with a macular detachment of less than 1 week duration obtain a final acuity of 6/18 or better as opposed to 50 percent with a macular detachment of 1 to 8 weeks duration. Patients should not be discouraged if initial acuity is poor because as the retina recovers, vision may continue to improve for upto a year.
Summary | |  |
Current techniques of rhegmatogenous retinal. detachment repair allow most detachments to be repaired successfully. The success of repair depends on a careful pre -operative examination and choice of an appropriate procedure. The surgery is usually tailored to individual needs. Improvements in surgical techniques coupled with a better understanding of the pathophysiology of rhegmatogenous retinal detachment continue to improve the anatomic and functional success of retinal detachment repair.
[Figure - 1]
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