Case Reports

Triamcinolone acetonide for remnant lenticule identification in small incision lenticule extraction

Case Report Details

First Author: S.Ramamurthy INDIA

Co Author(s):    G. Sachdev                    

Abstract Details

Purpose:

Retained lenticule fragments postoperatively is a unique complication following Small Incision Lenticule Extraction. Large or central remnants with pursuant complications including irregular astigmatism, induced corneal aberrations and reduction in visual acuity, warrant a surgical removal. Currently described modalities to delineate lenticule remnants include the use of an anterior segment optical coherence tomography or CIRCLE software. However, the incurred cost and restricted availability of the described techniques limit their widespread use. We demonstrate the intraoperative administration of diluted triamcinolone acetonide into the intrastromal pocket to delineate lenticule edges, aiding subsequent removal.

Setting:

A tertiary eye care hospital in South India

Report of Case:

The study adhered to the tenets of declaration of Helsinki, Ethics committee approval was obtained and an informed consent was taken. A 24-year-old female underwent SMILE for refractive correction of -1.50 Dioptre (D) sphere in both eyes elsewhere. The surgical course in the right eye was eventful resulting in suboptimal visual outcomes postoperatively. She presented to us on postoperative day two with complaints of persistent defective vision in the right eye, and a corrected distance visual acuity (CDVA) of 20/30 (with -2.0D sphere and -3.50D cylinder* 5 degrees). Left eye showed an uncorrected distance visual acuity (UDVA) of 20/16. Review of the surgical video demonstrated an adequate femtosecond laser pass with an ideal opaque bubble layer (OBL) formation and no dark spots. The extraction of the lenticule however was suboptimal with piecemeal removal, secondary to tearing of the thin 35 micron lenticule. Corneal tomography (Pentacam HR, Oculus Optikgeräte GmbH, Wetzlar, Germany) revealed irregular astigmatism with central steepening. Anterior Segment OCT (Avanti-Optovue, Fremont, CA, USA) was performed but it failed to demonstrate or delineate the lenticule remnant clearly. The patient was advised surgical exploration for lenticule removal. The procedure was performed under topical anaesthesia with proparacaine 0.5% eye drops. The interface was irrigated with diluted preservative free triamcinolone acetonide. 0.1ml of 40mg/ml solution (Aurocort, Aurolab, India) was reconstituted and diluted to 0.4 ml using balanced salt solution, with a final concentration of 1mg/0.1ml. The deposition of triamcinolone crystals at the lenticule edge allowed clear intraoperative delineation. The remnant was separated from the surrounding stroma and subsequently extracted using micro forceps. Spreading the lenticule on the corneal surface to ascertain complete removal is recommended. A thorough interface wash was carried out to remove the excessive triamcinolone particles. Corneal tomography postoperatively demonstrated corneal regularisation and the patient achieved a UDVA of 20/20.

Conclusion/Take Home Message:

Retained lenticule fragment in SMILE mandates surgical removal. ASOCT has potential shortcomings of limited availability, incurred cost and limitations in eyes wth stromal fibrosis and thin lenticules. CIRCLE software affords conversion of the SMILE cap into a flap, allowing open exploration and subsequent remnant removal. However, the construction of a flap nullifies the potential biomechanical advantage of the SMILE procedure. Additionally, the use is limited in the immediate postoperative period secondary to corneal edema or haze. We describe the use of diluted triamcinolone acetonide in the interface pocket allowing delineation of lenticule edges. Potential advantages include easy availability, low cost and application in eyes with thin lenticules or reduced visibility secondary to haze or edema. No intraocular pressure rise was noted with gradual dissolution of triamcinolone crystals from the interface.Additionally, the low concentration of triamcinolone (1mg/0.1ml) utilised is sufficient to delineate the lenticule while being devoid of any side effects.

Financial Disclosure:

None