Primary Retinal Detachment

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3 Encircling Operation with Drainage for Primary Retinal Detachment
Double patching and bed rest were encouraged whenever possible.
After localization of all breaks and cryopexy, 5-mm sponges were
applied in 82%. They were placed radially in 49% and circumferentially
in 33%. The primary success rate was 87%.
Reasons for Modification
As indicated above, the success rate depends on case selection,
length of follow-up, whose cases they are, who evaluates them, etc.
The impetus for change in the latter series was the unavoidable
morbidity associated with encircling and drainage. In order to
make sure that the overall success rate corresponded to the published
norm of 80–90%, modifications occurred gradually – first
by tying the band loosely, then by omitting it. Modifications were
also made by shortening the circumferential 7-mm explant and
finally by just buckling the breaks, preferably in a radial orientation.
Fewer and fewer cases were drained, sometimes at the cost of
sleep.
This experience somewhat parallels the trend described by
Lincoff,who drained 48% of cases in 1963 and only 13% by 1971 [39],
or by Kreissig who drained almost all cases in 1966, 6% of cases in
1972 [40] and none in 1992 [36]. The reasons for drainage were (1)
giant tears, (2) severe preretinal retraction, (3) uncertain localization
of the break, (4) defective choroid, (5) thin sclera, or (6)
glaucoma [39]. Reasons 1–3 might be managed by vitrectomy techniques
today including encircling with the ubiquitous 3.5-mm
band, which reduces indications for drainage.
Are Encircling and Drainage Still Worth Doing?
As every detachment surgeon knows,there are detachments of good
and of poor prognosis. Good prognostic signs include: fewer
breaks, less extensive area of detachment, shallow detachments and