Translational applications for a point-of-care molecular diagnostic kit in refractive surgery: the future!

Session Details

Session Title: Advanced Tools for Outcome Assessment

Session Date/Time: Tuesday 17/09/2019 | 08:30-10:30

Paper Time: 10:16

Venue: Free Paper Forum: Podium 4

First Author: : P. Khamar INDIA

Co Author(s): :    Z, Dadachanji    R. Shetty   A. Ghosh                       

Abstract Details

Purpose:

Corneal ectasia post refractive surgery and in keratoconus can compromise visual acuity. However, in cases with normal topographical and structural characteristics, it is difficult to predict adverse outcomes. Similarly, corneal collagen crosslinking outcomes in Keratoconus patients are unpredictable in terms of disease stabilization and visual recovery. Lysyl oxidase (LOX) is an endogenous crosslinker of collagen fibres which is influenced by inflammatory factors. Alterations in pre-existing LOX or MMP9 levels in corneal tissue of subjects undergoing refractive surgery or crosslinking correlates with clinical outcomes. Testing for such factors should help predict disease and treating those may improve prognosis and treatment outcomes.

Setting:

Narayana Nethralaya Superspeciality Eye Hospital , Bangalore , India

Methods:

Tear cytokines in patients with post refractive ectasia, dry eye &keratoconus were measured using multiplexing. A set of soluble factors including LOX, MMP9, etc that correlated with the clinical conditions were selected as prognostic biomarkers. Specific antibodies were developed against the selected set of analytes by immunising rabbits with the corresponding antigens. A solid phase assay system was developed with a dedicated laser based quantitative detector. The bound factors were detected using fluorescent tagged antibodies and signal intensity corresponded to the concentration of the analyte. Tear samples were collected from 5 subjects &tested for detection sensitivity &to establish comparative data.

Results:

LOX levels were reduced significantly (p<0.05) in cases of post refractive surgery ectasia when topography and biomechanics were normal. Significantly reduced LOX and increased MMP9 was observed in Keratoconus, apart from a variety of cytokines. Significantly elevated levels of cytokines was observed in dry eye tears. The kits developed were able to detect the purified antigen sets to establish a standard curve with the detector. The assay successfully detected the antigens from the tear samples of all the subjects. The standard curve was used to calculate the concentrations of the antigens in each sample.

Conclusions:

The biomarker kits can revolutionize predicting, detecting and treating corneal ectasias and streamline dry eye management. By improving preoperative screening protocols, we can improve patient selection criteria, avoid undesirable outcomes and develop bespoke management to optimize healing.

Financial Disclosure:

None