Primary Retinal Detachment

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3 Encircling Operation with Drainage for Primary Retinal Detachment
How Encircling Works
Similar to a circumferential buckle, encircling closes breaks by
corking them functionally at the crest, interrupting the conduit of
fluid through the hole. The constriction permanently reduces traction
on the break and volume reduction concentrates the vitreous
mass, both facilitating apposition of the retina and plugging of the
tear. This may be particularly beneficial in small undetected full
thickness holes, which remain relaxed, supported and corked and,
therefore, may never become functional. As Gonin said,“La masse
pulpaire du vitre,formant elle-meme bouchon au devant de l’ouverture,
favorise cette obliteration” [7].
With and without intraocular injection of gas the inferior retina
has been prone to break formation. In 1921, Gonin pointed to the
traction-reducing effect of the weight of the vitreous mass on the
inferior retina. He felt, however, that the inferior vitreous attachment
was firmer and of larger surface, “En revanche, par suite du
contact plus direct et plus durable qui existe entre la pulpe du vitre
et la retine dans les parties declives, les adherences ont chances d’y
etre plus intimes et plus etendues” [7].
Buckling of the vitreous base, as in encircling [14], might provide
protection against increased vitreous traction, particularly inferior.
Most vitreous proliferation starts inferiorly and is stimulated
by trauma or vitreous manipulation. Gas bubbles, depending on
buoyancy, may contribute to inferior traction directly. Encircling
protects the vulnerable vitreous base, as seen by the paucity of
retinal breaks after encircling as opposed to pneumatic retinopexy
[15], and the barrier effect of prophylactic laser treatments, which
include the inferior periphery [16].
Complications of Encircling
Complications of encircling include surgery in all quadrants in all
cases, increased myopia, strabismus, internal erosion, the string and