|Year : 2021 | Volume
| Issue : 4 | Page : 857
A novel technique to measure ocular decentration in the absence of eye-tracker during small-incision lenticule extraction surgery
Amber Amar Bhayana, Sudarshan Kumar Khokhar, Gauri Singh
Dr. Rajendra Prasad Centre for Ophthalmic Sciences, AIIMS, New Delhi, India
|Date of Web Publication||09-Oct-2021|
Dr. Amber Amar Bhayana
Dr. Rajendra Prasad Centre for Ophthalmic Sciences, AIIMS, New Delhi - 110029
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Bhayana AA, Khokhar SK, Singh G. A novel technique to measure ocular decentration in the absence of eye-tracker during small-incision lenticule extraction surgery. Indian J Ophthalmol Case Rep 2021;1:857
|How to cite this URL:|
Bhayana AA, Khokhar SK, Singh G. A novel technique to measure ocular decentration in the absence of eye-tracker during small-incision lenticule extraction surgery. Indian J Ophthalmol Case Rep [serial online] 2021 [cited 2021 Oct 26];1:857. Available from: https://www.ijoreports.in/text.asp?2021/1/4/857/327698
After cone applanation in Small Incision Lenticule Extraction (SMILE), a green blinking light is visible to the patient at the centre of cone [Figure 1]a. 2 perpendicular maximum diametersare drawn across the pupil [Figure 1]b. The point of intersection is taken as the pupil's centre. At https://eleif.net/photo_measure.html, calibration for online measurement is first done using a red line drawn as the diameter of the applanation cone whose value is known to be 8.3 mm (small size cone of VisuMax, ZEISS) [Figure 1]c- acting as reference.
|Figure 1: (a) Infrared images after applanation done and suction on, green light is the centre of the applanation cone. (b) Pupil centre proposed as the point of intersection of white lines. (c) Measurement of the diameter of the cone and respective calibration. (d) Amount of decentration proposed as the distance between the pupil centre and green blinking light- here was found to be 0.33 mm in the index case (yellow line)|
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We propose measurement of ocular decentration as distance between the green light (centre of the applanation cone) and the point of intersection of white lines (pupil centre) [yellow line in [Figure 1]d] in the absence of any eye tracker.
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Conflicts of interest
There are no conflicts of interest.
| References|| |
Blum M, Sekundo W. Refraktive lentikel extraktion – Technik der ReLEx/SMILE: Videobeitrag. Der Ophthalmologe 2017;114:851-6.