1300hrs: Pediatric Retinal Surgery (Khaled Tawansy)
/Original training at University of Michigan, fellowship at UBC and two others since then. Now a leader in pediatric retinal surgery. Both Drs Merkur and Albiani did additional training under his guidance after their fellowships here.
Two talks based on two patients. Juvenile retinoschisis is the first case.
This first one has to do with a 2 m.o. baby with eyes that started to wander upward. Fundus looks like has traingular areas of elevation with loops of vessels. FA helps show dome shaped elevation. This is Malignant Bullous Schisis. Usually presents before 18 m.o. with schisis that marches posteriorly to eventually often involve macula. Retina scrolls up into a fold.
Think X-linked Schisis when see vitreous heme, strabismus, amblyopia. Retinoschisin the involved protein mutation. A transmembrane protein involved in cell to cell adhesion.
Foveomacular schisis has several clinical presentations, one of which is the cartweel appearance at the fovea. If get foveal displacement, it does so nasally.
OCT often helpful to define the schisis area and also can show peripheral areas that might otherwise be missed. The areas that split correspond with the distribution of the retinoschisin protein in the eye.
Surgical indications include: vit heme, intra-schsis heme, bullous cavitty, progression to macula. Sometimes hard to tell where schisis ends and traction begins if retina detaching.
Back to the 2 m.o. patient who has lost fixation form schisis cavity extension. What are our options? Observe, intravit inj’n, laser, buckle, PPV, something else.
For management, presents a 3 week old with schisis and family history of exon 4 deletion. Shows how the retina starts to scroll off to the macular area. Quoting his mentor, Dr Ross, he opts for conservative approaches first, starting with a buckle, drainage of fluid, silicone oil. Child now stable more than 5 years and one of a series now collected who all had same exon 4 mutation and had surgery in first 2 years of life. All have 6/12-6/30 final acuity. Oil removed in 44%.
Now, back to the 2 m.o patients, management opted for was the encircling band, external drainage fluid. Careful not to create OUTER retinal hole in this process. Lens-sparing vitrectomy. Child has regained central fixation. What about the left eye for this patient? Here retina so bullous it is touching in many areas. Opted for injecting Plasmin and keeping patient in prone position.
Spontaneous reversal of schisis is felt to be something that can occur. Can see a ‘high water line’ indicative of where the fluid line was in the schisis cavity.
Has also seen some kids with thick exudates in their schisis cavitis. These have all been refractory to the standard surgical techniques already discussed. Requiring re-operations with relaxing retinal incisions and not as favourable in terms of visual prognosis.
Summary. Think of schisis in boys when see vit hem or vision changes. Many variations and may not appear in 1st year with Exons 1-3. With Exon-4 there are more malignant manifestations. There is also the Exudative variant that is particularly difficult.