Retinal test was used to categorize the
Retinal detachment is a sight threatening pathology where the retina isseparated from the retinal pigment epithelium layer. Rhegmatogenous retinaldetachment (RRD) is the most common type of retinal detachment usuallyassociated with bilateral predisposing pathology. Retinal detachment transpireswhen there’s a tear in the retina causing sub-retinal fluid to accumulate.
Ifthis isn’t treated quickly and efficiently with surgery, it will lead to lossof sight. Fellow eyes in cases of RRD have shown in studies to have an increasedrisk of RRD as there are increased rates of predisposing retinal degenerationand retinal breaks. Having RRD in the fellow eye is frequent for Rhegamtogenouspatients, but significant research on RRD has overall poorly considered thepredisposing pathology in the fellow eye of patients already with RRD. There is limited major research withregards to the pathology in the fellow eye, thus causing a problem with regardsto management of the ocular health. Subsequently if left untreated wouldeventually lead to blindness. The key objective of the target paper was topersonify the predisposing pathology and clinical features in the fellow eye ofthe patients that were a part of the Scottish Retinal Detachment Study.
The problem was solved by more significantresearch being done on fellow eye using cases from Scotland. The study was doneover 2 years recruiting people with primary RRD in Scotland which was approvedby the research and ethics committee. All patients had to be a resident ofScotland and have primary RRD which would’ve been examined by a consultantvitreoretinal surgeon using a bio-microscope. After the patient met therequirements then the surgeon would examine the fellow eye. A posteriorvitreous detachment (PVD) would be shown as a Weiss ring which would also berecorded. Horseshoe tears and giant retinal tears were categorised as posteriorvitreous detachment associated Rhegmatogenous retinaldetachment with a partial or complete PVD using bio-microscopy.
The two-samplet test was used to categorize the data and differences were put into orderusing the Z test of proportionality. Initially 1202 patients were recruited and 1130 were used over the2-year period as they had clinical signs and fulfilled all the requirements forthe study. The results from the 1130 cases showed posterior vitreous detachmentwas present in 87.6% and within this 990 with PVD; 98.5% had horse shoe tears and1.5% have giant tears. In the 1130 patients full thickness retinal breaks werepresent in 8.
4%, lattice degeneration in 14.5% and 13% had a best corrected VAof 6/18 or worse. Now the cases in which PVD was absent were 12.4% but fromthose 140, 40% had a round hole, 47.8% had retinal dialysis and 12.1% had retinoschesis.
The research suggested that RRDin the fellow eye has an increased risk causing danger to sight. In 8.4% full-thickness retinalbreaks were treated using laser/ cryotherapy treatment.The amount of fellow eye retinal breaksin RRD with PVD and without PVD were very similar which is also similar toprevious reports over a 5 year follow up.
The findings of this study suggested that Latticedegeneration was found to be more prevalent in fellow eyes with RRD without PVDthan in fellow eyes with RRD with PVD (20.7% vs 13.6%).
RRD in the fellow eyeis more likely with a smaller area of detachment and a macula that’s stillintact when matched to unilateral RRD showing an increased awareness of patientsymptoms. Even though we can detect and have prophylactic treatment for retinalbreaks in the fellow eye, around 6% of those treated patients ended updeveloping RRD in the eye that has received treatment. The final point deducedis 1/10 fellow eyes have a best VA of 6/18 or less and from those in 20 % ofcases it is caused by previous RRD.
Previous reports suggested15-19% of RRD are bilateral so effective preventive treatments should be usedon patients, but large groups weren’t examined to see the effects of preventivetreatment on the fellow eye. Merin et al (1971) conducted a national study toexamine treatments to prevent RD, in Israel. The methods used to examine thefellow eyes were direct and indirect ophthalmoscopy, but when necessary Goldmanthree-mirror lens was also used to examine the eye. Retinal Detachment found inthe fellow eye was reported to a co-ordinating centre, but the reports wereincomplete and treatment wasn’t used on all cases. A high percentage of caseshad retinal degenerative changes in fellow eyes but it was quite normal for theeyes to be predisposed to holes and detachment.
From this it was deduced thatlattice and snail-track degenerations were 3 times more likely to be withretinal holes than without them. Using effective prophylactic treatments, overallthere was a fall in retinal detachment in the fellow eye from 10.9% to 4.2%from 1962 to 1968. The reports in thestudy were incomplete, in addition the preventive treatment was used in the incorrectway or even not used at all.
This issue was highlighted inMerin et al (1971), subsequently led to the target paper tackling problem.Motivated by the findings of the effects of RRDin the fellow on visual acuity in the target paper to report the long termvisual effects of RRD. After initial surgery patients were invited for followup appointments, to estimate the effect on vision using a joinpoint model. Theresults showed that 291 cases had successful repair of RRD after the firstoperation where 192 of patients achieved a visual acuity of 6/18.
Using thejoinpoint model it showed that after 8 days the visual acuity was statisticallygetting worse if untreated. Mitry et al (2012) concluded that initialsuccessful surgery on RRD will have at least 6/18 visual acuity at the finalfollow up after 1 year. If the RRD is left for more than 8 days vision isseriously affected. Thus it’s best to have the operation before as it showed acontinuous improvement in visual acuity for up to a year which wasn’t the samefor patients with RRD for longer periods.