small pupil phacoemulcifiction a preoperative evaluation should include pupillary dynamics poor...

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Small pupil phacoemulcifiction

Small pupil phacoemulcifiction A preoperative evaluation should includepupillary dynamics Poor pupillary dilatation should be detected and noted Appropriate history is important for detecting any underlying etiology of the miotic pupil (use of miotics or long-standing diabetes ) intraop miosis (iris manipulation)

Small pupil phacoemulcifictionAny co-existing condition, such as zonular weakness in pseudoexfoliation or synechiae in chronic uveitis, should be detected preoperatively

Sphincter-sparing techniques

Pharmacological mydriasis: combination of cycloplegic, mydriatic and NSAID drops.not effective in cases with posterior synechiae, pupillary membrane or scarred pupils. Such pupils need intraoperative procedures. High molecular weight cohesive viscoelastics such as Healon 5 or Healon GV can be injected into the center of the pupil

Sphincter-sparing techniquesIf this does not work, synechiolysis may be done with a blunt spatula passed through the side-port incision. Viscomydriasis can then be repeated. Pupillary membranes can be stripped mechanically by Utrata forceps Pure, preservative-free adrenaline can be added to the irrigation bottle after appropriate dilatation (Care should be taken in hypertensives)

Sphincter-involving techniquesDilatation can also be achieved by pupillary stretching using push-pull instruments. Under viscoelastic cover, two hooks are used in a slow, simultaneous, controlled fashion to stretch the pupil in or more axes.

Stretch pupilloplasty with Kuglen's hooks

Sphincter-involving techniques Mini sphincterotomies less than 1 mm and limited to the sphincter tissue, can be made with either Vannas scissors or vitreoretinal scissors. This gives adequate dilatation intraoperatively and maintains a functionally and aesthetically normal pupil postoperatively.

Mini sphincterotomies

Pupil stretcher devices

Sphincter-involving techniques iris hooks Commercially available iris hooks can be used to stretch small pupils The disadvantage of pupil stretch techniques is that the iris sometimes becomes flaccid and prolapses through the incision during surgery

iris hooks

Sphincter-involving techniques Pupil rings Pupil rings have been introduced to stretch the pupil without sphincter damage They are inserted through the main port and manipulated into the pupil space

The Perfect Pupil developed by John Milverton, MD

Sphincter-involving techniquesIt can be inserted through an incision of less than 100 m. Because of the open ring design of the Perfect Pupil, there is no interference with other instrumentation.

Sphincter-involving techniques Malyugin ringIt is inserted with forceps or injected with an injector through the main port

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