Primary Retinal Detachment

Origins of Encircling: Arruga and Schepens 37
Fig. 3.2. A 32-year-old myopic woman whose eye was constricted with a
55-mm overlapping band. The fundus drawing shows the “purse-string
sign”, meridional folds and the barrier function which is incomplete inferiorly
of the 2.5-mm band. The eye was uncomfortable with signs of
iritis as part of the “string syndrome”
Breaks posterior to the crest would lead to failure, whereas
those too far anterior to be buckled could be walled off by diathermy
barriers.After drainage, the encircling band was shortened
up to 25–30 mm in severe cases of massive vitreous retraction.
Since the retinal circumference at the equator measures 72 mm in
the emmetrope, such reduction was 40%, complicated by meridional
folds or fishmouthing of the horseshoe tear(s) and subsequent
redundant folds across the crest of the buckle (Fig. 3.2).
The 1957 encircling operation closed breaks in the chosen latitude
and walled off anterior breaks, but it did not reliably support
the anterior horns of horseshoe tears [11, 12].Anterior buckling was
improved by the addition of myriad shapes of wider explants,
including “accessories”, “radial wedges” and “meridionals,” which
are still available commercially today [13].