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| ORIGINAL ARTICLE |
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| Year : 1994 | Volume
: 42
| Issue : 1 | Page : 27-30 |
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Selection of surgical technique for retinal detachment with coloboma of the choroid
Subhadra Jalali, Taraprasad Das
L.V. Prasad Eye Institute, Hyderabad, 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: 7927627 
Four eyes with rhegmatogenous retinal detachment and coloboma of the choroid were managed by conventional scleral buckling (one eye); scleral buckling combined with lensectomy, vitrectomy, and fluid-air exchange (two eyes); and vitrectomy, silicone oil injection without scleral buckling (one eye). Retinal break was seen within the coloboma in two eyes, at the periphery in one eye, and, both in the coloboma and periphery in one eye. At a follow-up of 15 months, the retina was found attached in all the patients. The success of these surgical procedures could be attributed to careful preoperative/intraoperative fundus examination and individualised surgical planning Keywords: Coloboma choroid - Retinal detachment
How to cite this article:
Jalali S, Das T. Selection of surgical technique for retinal detachment with coloboma of the choroid. Indian J Ophthalmol 1994;42:27-30 |
Coloboma of the choroid is a rare condition, which results from faulty closure of the embryonal fissure. Forty percent of such patients may develop retinal detachment. [1] Management of these cases can be done by conventional scleral buckling if the breaks are outside the colobomatous area. However, this technique would fail if the break is in the hypoplastic retinal tissue, within the colobomatous area. We report the various surgical techniques which were successfully used in the four cases of retinal detachment associated with coloboma of the choroid.
| Materials and methods | |  |
Four eyes of four patients who had rhegmatogenous retinal detachment associated with coloboma of the choroid were the subjects of this study. The duration of loss of vision at the time of surgery ranged from 11/2 to 3 months and the visual acuity was from perception of light (PL) to 6/60. Associated ocular conditions included presence of coloboma of the iris in all eyes, cataract in two eyes, microphthalmia with exotropia in one eye, and high myopia in one eye. None of the eyes had nystagmus or coloboma of the disc. In one patient (case 2) the macula was involved by the coloboma; two fellow eyes had no vision (one eye was anophthalmic and the other eye had total retinal detachment); one patient had a visual acuity of 6/9 with coloboma of the choroid; and one fellow eye did not have any abnormality. The details of the patients and their preoperative ocular status are shown in [Table - 1].
| Case reports | | |
Case 1. A 21-year-old woman was seen in April 1992, with a history of profound impairment of vision in both eyes of two months' duration. On examination, her visual acuity was counting fingers at 50 cm in the right eye and 25 cm in the left eye. Both eyes were quiet and had a typical iris colobomata and posterior subcapsular cataract with phacodonesis. Fundus examination of both eyes showed a total retinal detachment associated with a choroidal coloboma, not involving the disc and macula [Figure - 1]a. In the left eye, a retinal break was suspected within the coloboma.
Surgical technique: Due to the presence of significant cataract and absence of any peripheral retinal break, a pars plana lensectomy and vitrectomy was done. Using high magnification, the break within the colobomatous area was confirmed during vitrectomy. Through this retinal break, internal drainage of subretinal fluid and fluid-air exchange was done using a back flush silicone brush cannula. The retina settled under air. Endolaser was done along the edges of the coloboma and the anterior margin was treated with transscleral cryopexy. The entire inferior half of the retina was supported by a broad circumferential tire (#280, MIRA).
Case 2. A 19-year-old man was seen in June 1992, with a history of sudden loss of vision in the right eye of three months' duration and absence of the left eyeball since birth.
On examination, the visual acuity in the right eye was perception of light with accurate projection. The left eye had congenital anophthalmos. On slit-lamp biomicroscopy, he had a typical iris coloboma and an inferior cortical cataract. Fundus evaluation showed a typical choroidal coloboma with a total retinal detachment. A break was detected at 8 o'clock position near the ora, outside the area of the coloboma [Figure - 1]b.
Surgical technique : A simple scleral buckling consisting of 360° circumferential tire and encirclage (# 279 MIRA, # 40 MIRA) with external drainage and cryopexy of the break was done. However, the retina did not settle intraoperatively. Hence, the procedure was converted to a more radical one consisting of lensectomy, vitrectomy with possible internal drainage, and fluid-air exchange. During vitrectomy a break in the colobomatous area was detected under high magnification. Internal drainage through the break located inside the coloboma and fluid-air exchange was done. After attachment of the retina, transscleral cryopexy to the anterior horns and endophotocoagulation to the posterior margins of the coloboma was done.
Case 3. A 25-year-old man was seen in March 1993, with a history of decreased vision in the right eye of one month duration. On examination, the visual acuity in the right eye was accurate projection and in the left eye was 6/6. The left eye was normal. The right eye had a typical iris coloboma and a clear lens. Fundus evaluation showed a total retinal detachment with a possible break in the area of the coloboma [Figure - 1]c.
Surgical Technique: A primary vitrectomy, fluidair exchange, and internal drainage through a break in the colobomatous retina was done. The retina did not settle under air on the operating table, instead was found stretched taut over the coloboma. This taut and thinned out retina was relaxed by stroking it with the silicone brush so as to create a couple of relaxing incisions. Following this, some more subretinal fluid was drained and silicone oil was injected. This was followed by transscleral cryopexy and endolaser photocoagulation as in cases I and 2. Because of the absence of peripheral retinal breaks, scleral buckling was not considered. The silicone oil was removed 8 months later and there was no recurrent retinal detachment.
Case 4. A 28-year-old man was seen in June 1991, with a history of decreased vision in the right eye of 1 1/2 months' duration. He was using high myopic correction in both the eyes (- 14D sphere) for the past 15 years. On examination, the visual acuity was 6/ 60 in the right eye and 6/9 in the left eye. The anterior segment evaluation showed typical iris coloboma in both the eyes. In the right eye, the lens was clear but had phacodonesis. Fundus examination of the right eye showed a temporal half retinal detachment with a horse-shoe tear at the 10 o'clock position near the ora [Figure - 1]d. The detachment did not extend to the colobomatous area inferiorly. He underwent conventional scleral buckling, encirclage (# 276 MIRA, # 240 MIRA), and external drainage of the subretinal fluid.
| Results | | |
The study included three men and one woman.The average age of the patients was 23.2 years (range, 19 to 28 years). The mean follow-up period was 16.5 months (range, 9 to 27 months). The retina was attached in all the eyes at the last review and visual acuity ranged from 6/15 to 6/24. The detailed patient data is shown in [Table - 2].
| Discussion | | |
Retinal detachments associated with coloboma of the choroid present a surgical challenge. In the colobomatous area the retinal tissue is thin and hypoplastic, the choroid and retinal pigment epithelium (RPE) are not developed and the underlying sclera is thin and ectatic, producing a staphyloma. Retinal breaks within such abnormal tissue are difficult to identify because of the lack of contrast. They can neither be sealed by retinopexy due to absence of choroid and RPE, nor can a buckle be placed due to the posterior location of the breaks. Other difficulties which confound the management in these cases include presence of associated ocular anomalies such as microphthalmia, cataract, lens coloboma, and along with nystagmus. [2]
Various techniques have been described to manage these complicated cases. These include use of two radial buckles along the two edges of the coloboma 2 one radial buckle extending upto the optic disc at one edge of the coloboma detected to be harbouring the retinal break, [3] primary vitrectomy, silicone oil injection with endolaser photocoagulation 4 and primary vitrectomy, intraocular long-acting gas tamponade with endophotocoagulation. [5]
Wang and Hilton [2] have reported 35% retinal reattachment using two radial buckles along the two pillars of the coloboma. Conventional scleral buckling was successful in only one of the six eyes which underwent the procedure. They opined that these techniques were not well suited for the colobomatous eyes, with unpredictable and invariably poor surgical results. They hypothesised that the preferred method could be vitrectomy, endophotocoagulation,and fluidgas exchange. [2] In the series of 17 eyes reported by Gopal et al, [4] silicone oil was used to tamponade the retina after vitrectomy and internal drainage of the subretinal fluid.
Anatomical success was achieved in all the eyes at two-month follow-up visit, but a 33% rate of recurrent detachment was seen when the silicone oil was removed within 4 to 16 months of surgery. Persistent secondary glaucoma ( three eyes ), and band keratopathy (four eyes) were the other complications.
The current surgical method for the management of retinal detachment with coloboma choroid includes vitrectomy, internal drainage of the subretinal fluid, long-acting gas or silicone oil tamponade, endophotocoagulation along the edges of the coloboma posterior to the equator, transscleral cryotherapy along the pillars of the coloboma anterior to the equator, coupled with occasional inferior half broad scleral buckling, [5] and optional lensectomy.
In our opinion, no single technique could be applied universally to all the cases of choroidal coloboma with retinal detachment. The surgical planning should be individualised for best use of the available technology. The key lies in a careful preoperative assessment of the retinal detachment, discussion with the patient and willingness to switch from a simple scleral buckling to a combined surgery, if so required on the operating table.
Partial retinal detachments not extending inferiorly to the colobomatous area are invariably due to a peripheral retinal break and are best managed by conventional scleral buckling (case 4). Primary vitrectomy, search for retinal break i n the colobomatous area, internal drainage of subretinal fluid, and internal tamponade with air/gas or silicone oil, is required when the retinal detachment involves the colobomatous area. The search for the retinal break is made with the aid of an endoillum nator under high magnification of the operating microscope using a silicone brush. Invariably the retinal break lies in the colobomatous area (cases 1, 2 and 3). The breaks are often not visualised preoperatively under low magnification of an indirect ophthalmoscope coupled with lack of background contrast offered by the coloboma. However, the peripheral retina outside the area of the coloboma should still be examined carefully for a break, because without support of a buckle surgical failure could result.
A peripheral retinal break and break within the coloboma could co-exist (case 2) and in these situations a segmental buckling to support the peripheral break is mandatory.
If the retina is easily attached, we do not normally advocate silicone oil injection. In patients with advanced proliferative vitreoretinopathy (PVR), we do feel that silicone oil tamponade might be better than long-acting gas, as suggested in one study [4] However, in a randomised clinical trial no significant advantage was found in the rate of retinal reattachment in eyes with advanced PVR ( > C3 ) whether treated with oil or perfluoropropane gas (C 3 F 8 ) in eyes that had already undergone vitrectomy ; and C3F, had better results where no previous vitrectomy had been done . [6 ]sub Silicone oil injection, however, carries certain risks, one of them being redetachment following oil removal. [4] Our series is too small to give a preferential choice between oil or gas tamponade. However, we prefer to use long-acting gas (C 3 F 8 ) unless the retinal detachment is associated with advanced PVR. Meticulous retinopexy with endolaser and transscleral cryopexy is mandatory to isolate the area of the coloboma from the rest of the retina. Lensectomy is optional, depending on the clarity of the lens. We feel that this stepwise and individualised surgical approach would give the best possible anatomical and visual results i n a given patient of coloboma choroid with retinal detachment.
| References | | |
| 1. | Jesberg DO, Schepens CL. Retinal detachment associated with coloboma of the choroid. Arch Ophthalmol. 65:163-173,1961.  |
| 2. | Wang K, Hilton GF. Retinal detachment associated with coloboma of the choroid. Trans Am Ophthalmol Soc. 83:49-62, 1985. |
| 3. | Patnaik B, Kalsi R. Retinal detachment with coloboma of the choroid. Ind J Ophthalmol. 29:345-349, 1981. |
| 4. | Gopal L, Mohandas MK, Badrinath SS, et al. Management of retinal detachment with coloboma choroid. Ophthalmology. 98:1622-1627, 1991. |
| 5. | Michels RG, Willkinson CP, Rice TA. Retinal detachment. St. Louis, C V Mosby. pp. 724-727,1990. |
| 6. | The silicone study group: Vitrectomy with silicone oil or perfluoropropane gas in eyes with severe proliferative vitreoretinopathy. Results of a randomized clinical trial. Silicone study report 2. Arch Ophthalmol. 110:780-792, 1992. |
[Figure - 1]
[Table - 1], [Table - 2]
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