Intraoperative, real-time OCT-guided big bubble–deep anterior lamellar keratoplasty in the pediatric patients

Volume 21 Number 4 / August 2017 070 Intraoperative, real-time OCT-guided big bubble–deep anterior lamellar keratoplasty in the pediatric patients. Ta C. Chang, Carla J. Osigian, Mohamed S. Sayed, Kara M. Cavuoto, Mohamed F. Abou Shousha Introduction: Deep anterior lamellar keratoplasty (DALK) allows preservation of the host endothelium in patients with endotheliumsparing corneal disease. Injection of an intrastromal air bubble allows for baring of the Descemets membrane, which helps achieve optimum postoperative visual results. We report our experience using real-time anterior segment optical coherence tomography (AS-OCT) to guide the depth of stromal dissection and "big bubble" injection in pediatric patients undergoing big bubble DALK. Methods: Intraoperative, microscope-integrated real-time AS-OCT was utilized to guide needle insertion into deep stroma, air bubble injection, and lamellar dissection. Results: Three eyes of 3 children under 4yo with dense amblyopia secondary to corneal scarring underwent DALK. Real-time AS-OCT was successfully used intraoperatively to guide the procedure. A DM microperforation occurred in one case, in which AS-OCT demonstrated the presence of a double anterior chamber and allowed fluid drainage under direct visualization. Absence of fluid and air in the interface was demonstrated at conclusion of surgery in all patients. Discussion: Adequate dissection can be expected if pneumatic dissection is performed at a sufficiently deep level. The technique is challenging, particularly in pediatric corneal grafting. To our knowledge, this is the first report of utilizing real-time AS-OCT guidance in pediatric DALK. It allows direct visualization of corneal layers and precise depth assessment, facilitating time-efficient intraoperative surgical decision-making, and enhancing reproducibility of the procedure. Conclusions: Intraoperative, real-time AS-OCT guided pneumatic dissection may improve the success rate of DM baring, improving surgical outcomes in pediatric patients undergoing DALK, and facilitating visual development. 071 Abnormal optic nerve (ON) traction on the globe during adduction in normal tension glaucoma (NTG). Robert A. Clark, Soh Y. Suh, Joseph Caprioli, Joann A. Giaconi, Kouros Nouri-Mahdavi, Simon K. Law, Laura Bonelli, Joseph L. Demer, Anne Coleman Introduction: ON straightening by medial rectus muscle counterforce during adduction may mechanically load the globe-ON junction, creating repetitive strain that could produce intraocular pressure (IOP) independent progressive ON degeneration in NTG. Methods: Sixteen NTG patients and 30 normals underwent high-resolution, surface coil, quasi-coronal orbital magnetic resonance imaging in central gaze, abduction, and adduction to angles measured by displacement of globe-ON junctions. Globe size was estimated from images. ON area centroids were plotted in three-dimensions (3D) to determine ON lengths relative to minimum straight-line paths. Globe translation was determined 3D centroid displacement and globe elongation was calculated from differential translation of the posterior border of the globe. Results: Average abduction (20.8  1.0 vs 20.7  0.8 ) and adduction (28.2  0.9 vs 26.6  1.1 ) angles were similar between groups. Coronal globe diameters were significantly larger in NTG (25.9  0.2 versus 25.2  0.2 mm, P 5 0.01). The ON significantly

Journal of AAPOS

e23 straightened only in adduction for both groups: 102.1%  0.2% of minimum path length in adduction versus 104.4%  0.5% in central gaze for NTG (P 5 10 7), and 101.6%  0.1% versus 102.7%  0.3% for normals (P 5 10 5). During adduction, the globe shifted medially in both groups, but in NTG the globe center retracted significantly farther posteriorly (0.7  0.1 vs 0.1.0  0.1, P 5 10 6) and elongated vertically (0.5  0.1 vs 0.2  0.1, P 5 10 5). Discussion: In NTG, ON straightening during adduction abnormally pulls the globe posteriorly and elongates the globe inferiorly, reflecting globe tethering with mechanical loading of the globe-ON junction. Conclusions: Although ON tethering in adduction is normal, in NTG there is greater globe displacement and deformation that may cause IOP-independent, neuropathic mechanical loading of the ON head and peripapillary sclera. 072 Ahmed valve capsulectomy in children: a retrospective chart review. Lauren E. Fletcher, Rosie Lee, John Roarty Introduction: The use of glaucoma drainage implants is a common treatment for pediatric glaucoma when pressures cannot be controlled. Previous studies have reported failure of Ahmed valves when the plate of the valve develops a fibrous capsule leading to elevated intraocular pressures (IOPs). The purpose of this study was to evaluate the success of Ahmed valve Capsulectomies in children. Methods: The medical records of patients aged 2 months to 15 years that had Ahmed valves placed with subsequent capsulectomies between November 1999 and May 2016 were reviewed. Patients were evaluated prior to Ahmed valve placement, and followed monthly until Ahmed valve failure. Patients were then followed monthly after capsulectomy was performed. Surgical success was defined as post-capsulectomy IOP similar to IOP prior to valve failure without additional procedures. Results: A total of 14 capsulectomies from 13 eyes of 10 patients were studied. The mean pre- and post- Ahmed valve IOP was 33  4 and 17  4, respectively. The mean failed IOP was 29  4, and the mean post-capsulectomy was 19  3. There was an overall 37% drop in IOP after capsulectomy (P 5 0.004). Of 14 capsulectomies, 7 failed an average of 15 months post-capsulectomy. Discussion: Removal of valve capsules results in lower IOPs in the pediatric population. This could prove to be a temporizing if not permanent solution in children that may otherwise require further surgery to lower IOP. Conclusions: Ahmed valve capsulectomy is a safe and effective option in children who have failed tube shunt surgery secondary to capsule growth over the valve plate. 073 Pediatric cataract surgery: unexpected returns to the operating room within one year. William J. Johnson, M. Edward Wilson, Rupal Trivedi Introduction: Previous studies have provided excellent data regarding the reoperation rates for infant eyes undergoing cataract surgery at less than 7-months of age. At present, generalizable data for incidence of unplanned return to the operating room following cataract surgery in the full spectrum of the pediatric age group are not readily available. Methods:Retrospective chart review, with IRB approval, was carried out for eyes undergoing cataract surgery at a single institution 8/2012