|Year : 1983 | Volume
| Issue : 6 | Page : 719-722
Peripheral retina in myopia
Manoj Shukla, OP Ahuja
AMU Institute of Ophthalmology, Aligarh, India
Lecturer, A.M.U. Institute of Ophthalmology, Aligarh-202 001
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Shukla M, Ahuja O P. Peripheral retina in myopia. Indian J Ophthalmol 1983;31:719-22
Periphery of the retina is defined as an area which is located anterior to the globe's equator. It is a site of predilection for a number of potentially dangerous pathological lesions including retinal breaks. The present study highlights some of the important pathological lesions of the peripheral retina in myopic eyes vis-a-vis their role in the causation of retinal detachment.
| Materials and methods|| |
The present investigation was undertaken in 768 myopic eyes studied in three groups.
GROUP I: It included 500 eyes of 250 myopic subjects who were collected randomly from refraction units without any symptoms related to a retinal disease. The refractive error of these individuals varied from-0.75 D.Sph to -40 D.Sph.
GROUP II: It includes 156 eyes of 140 myopic subjects having rhegmatogenous retinal detachment which was bilateral in 16 patients. The refractive error of the effected subjects varied from -2.50 D.sph to -28 D.sph.
GROUP III: It includes 112 fellow eyes of myopic patients who had rhegmatogenous retinal detachment. 12 fellow eyes could not be examined on account of corneal opacity, cataract, posterior synechia and phthisis bulbi. The refractive error of the subjects varied from -1.50 D.sph to -28 D.sph.
The peripheral retina was examined by a binocular indirect ophthalmoscope and scleral depressor after maximal dilatation of the pupils. It was supplemented by posterior segment biomicroscopy with a Goldmann's three miror contact lens in eyes showing pathological lesions.
| Observations|| |
A number of pathological lesions of peripheral retina were observed in the present study.
1. Peripheral cystoid degeneration:
It was observed bilaterally in all the eyes (100%) in different groupos without predilection for any age or sex. The degeneration was characterized by coarse or fine small cavities which appeared separate or sometimes confluent. Thedegeneration was graded from I-IV (1). Grade II involvement was the commonest in Group I while higher grades were commonly seen in eyes of Group III. No hole or tear was seen in the areas of cystoid cavities.
2. Acquired Retinoschisis:
This condition of splitting of retina at the level of outer plexiform layer was seen in 8 (1.60%) eyes of 8 (3.20%) subjects in Group I. The refractive error of the affected eyes varied from -5.0 D.sph to -10.0 D.sph. Extensive retinoschisis complicated by rhegmatogenous retinal detachment was observed in 4 (2.56%) eyes of Group II while fellow eyes of retinal detachment cases did not reveal this phenomenon.
3. Chorio-retinal degeneration:
It was seen in the form of greyish-black pigment mottling in the retina adjacent to the Ora serrata billaterally in 112 (22.40%) eyes of 56 subjects in Group I. More than fifty percent of the affected subjects belonged to third and fourth decades of life. The degeneration was seen in 12 (15.38%) eyes of Group II and 14 (16.07%) eyes of Group III. The condition was graded into mild, moderate and severe and was found to have an inverse relationship with cystoid degeneration i.e. eyes with severe chorio-retinal degeneration had mild cystoid degeneration and vice versa. No retinal break was seen in association with chorio-retinal degeneration.
4. Paving stone degeneration;
It was seen as pale, discrete or confluent lesions of retinal thinning, '/2 to 2 DD in size revealing underlying choroidal vessels. In Group I, 104 (20.80%) eyes of 78 (31.20%) subjects were affected thus showing bilateralism in 26 (33.33%) subjects. The degeneration was commonly seen in the third and fourth decades of life without predilection for any six. The lesions were most commonly observed in the suboral region of infero-temporal quadrant without any relation to retinal breaks. In eyes with retinal detachment and fellow eyues of retinal detachment cases, an incidence of 14.72% eyes and 16.24% eyes was observed.
5. White with pressure (WWP):
The phenomenon of opacification of retina after scleral indentation was seen most commonly in the second decade of life in 138 (27.60%) eyes of 86 (34.40%) subjects being bilateral in 52 (60.46/) of them (Group I). in eyes of group III a corresponding incidence of 34% eyes was observed.
The lesions were most commonly seen in the suboral region followed by equatorial region and presented different geographical shapes. Temporal half of the retina was affected more frequently than the nasal half and as a rule the lesions were more extensive in higher degree of myopia. Although localised adhesions of posterior hyaloid of the vitreous with individual WWP lesion were observed, no frank retinal breaks were seen in areas of WWP in eyes of group I and III.
6. White without poressure (WWOP):
This lesion appeared as an apparent whitening of the retina without scleral indentation. It was seen in 42 (8.40%) eyes of 28 (11.24%) subjects being bilateral in 14 (50%) of them in Group I. The retina looked thick and slightly opaque without any retinal detachment. As a rule the lesions were more advanced and extensive in eyes having a myopia of moderate tosevere degree. The lesions affected equatorial and post-equatorial regions of the retina and were seen in family members of 4 affected subjects. In Group III, the lesion was seen in 10(8.9%) eyes having a myopia of -4.0 D.sph to -14.0 D.sph. 6 partial thickness round holes were seen in areas of WWOP in three eyes and were responsible for symptoms of photopsia.
7. Pigmentary degeneration:
It was seen in the form of isolated pigment clumps or diffuse sectorial or 360° pigmentation in 122 (24.40%) eyes of 84 (33.60%) subjects in group I being bilateral in 38 (45.24%) of them. The degeneration was four times more commonly seen in males than females and affected most commonly the equatorial region of the retina and was more extensive in eyes having higher degree of myopia. In eyes of group II and III, an incidence of 12.72% and 14.86% respectively was observed without relation to retinal breaks.
8. Lattice degeneration:
Lattice degeneration was seen in the form of elongated well demarcated white patches lying circumferentially around the retinal periphery, being characterised in well established cases by a net-work of branching white lines.
Lattice degeneration was seen in 68 (13.60%) eyes of 42 (16.80%) subjects being bilateral in 26 (61.19%) of them. The degeneration was seen most commonly in the second and third decades of life without relation of any six and affected equatorial region of the retina (58.24%) in the supero-temporal quadrant (60.24%) most frequently. 8 eyes shows extensive (360°) lattice degeneration. As a general rule the degeneration was seen more commonly in eyes having a myopia of > 3 D. A total of 46 partial thickness round holes were seen inthe substance of individual lesions in 20 (29.41%) eyes of 14 (30%) subjects. Family members of six subjects having lattice degeneration also revealed similar lesions.
Lattice degeneration was the causative factor for retinal detachment in 42 (26.67%) eyes. A total of 78 retinal breaks were seen in relation to lattice lessions. Round holes were responsible for retinal detachment in 34 (80.95%) eyes while flap tears at the posterior margin of lattice lesions were present in 8 (19.05%) eyes. The maximum incidence of retinal detachment due to lattice degeneration was seen in fourth and fifth decade of life.
Lattice degeneration was seen in 24 (21.43%) eyes, 14 of these sharing a bilateral involvement. A total of 36 round holes were seen in the substance of individual lesions. Five eyes had 360°sub lattice degeneration in multiple tears. Symptoms of light flashes were present in four eyes.
Follow up was possible in 50 eyes having lattice degeneration in different groups. Over a period of four years. New lesions developed in four eyes in groupo I and five eyes in group III while round holes were seen in old lattice lesions in five eyes of group I.
9. Snail track degeneration
It was seen in 22 (4.40%) eyes of 14 (5.60%; subjects bein bilateral in 8 (57.14%) of them it Group I. The lesions appeared as elongated patches of retinal thinning without any branching white lines and affected equatorial region of the supero-temporal quadrant most frequently. In 7 eyes, the lesions were seen in associatidn with lattice degeneration. The degeneration was most commonly seen in second decade of life without prediliction for any six and was responsible for retinal detachment in four eyes of group II. 5 (4.46%) eyes were affected with isolated snail track lesions in group III. Family members of four subjects in group I also revealed snail track lesions.
10. Retinal breaks
A total number of 374 retinal breaks were observed in 978 eyes studied. 286 retinal breaks were seen in 144 out of 156 eyes with rhegmatogenous retinal detachment with an average of 1.98 break per eye. The number of retinal breaks in an eye varied from 1/14. Round holes in relation with lattice degeneration follows by flap tears were the commonest type of retinal breaks causing retinal detachment. The most frequent site for retinal breaks was equatorial region (64.25%) in the supertemporal quadrant (42%). Giant tears extending from 90° - 240° were seen in 13 eyes of 13 subjects (average age 27 years). All affected eyes had myopia ranging from -7.00 D. sph to - 20.00 D.sph and varying degree of massive peri-retinal proliferation (MPP) was present in 10 eyes.
| Discussion|| |
The discovery of binocular indirect ophthalmoscopy has given a big boost to the study of peripheral retina. This has been immense help in the examination of the retina of the myopic subjects who are frequently affected bydangerous pathological lesions in the retinal periphery. The results of this study once again highlight that myopic subjects are the target for such lesions which can predispose to retinal detachment any time during their life time. These lesions are commonly seen bilaterally in myopic individuals having a myopia of more than 3 D. The retina being weak on account of these trophic and tractional degenerative lesions is prone for developing retinal detachment even with a most trivial trauma to the eyeball. It is therefore, very essential to screen the peripheral retina of myopic individuals specially young children in order to timely detect such lesions. Further, a periodic examination (6 months to 1 year) of myopic subjects by a qualified retinologist is extemely important. Family members of myopic subject should also be screened as certain tractional degenerative lesions of peripheral retina tend to occur in families. Lesions like retinal breaks, lattice degeneration, snail track degeneration and white without pressure need closer observation in view of their frequent association with retinal breaks and retinal detachment. These lesions are often responsible for symptoms of light flashes and as such merit prophylactic treatment (2).
Fellow eyes of myopic detachment cases should receive greatest attention. Prophylactic cryopexy or photocoagulation is stongly indicated for pathological lesions in these eyes. Follow up of fellow eyes is extremely important to detect fresh lesions.
High myopia being the single most important factor in the etiology of rhegmatogenous retinal detachment should around more interest among general ophthalmologists and a determined effort to examine myopic subjects - by indentation indirect ophthalmoscopy would be the most important step towards prevention of retinal detachment in myopic eyes,
| Summary|| |
The present investigation was underetaken in 768 myopic eyes to study various degenerative lesions of peripheral retina specially with regards to their role in the development of retinal breaks and retinal detachment. The clinical features of various lesions are discussed and it is strongly adovocated that my opic eyes should receive prompt attention from the ophthalmologists as time propohylactic management of pathological lesions would be very beneficial in the prevention of retinal dc attachment.
| References|| |
Rutnin, U. and Schepens, C.L., 1967, Amer. J.Ophthalmol. 64: 1040
Shukla. M. and Ahuja, O.P., 1982, Ind.J.Ophthalmol. 30: 91.