Overview
To record the vascular changes that may be present in the macular after uncomplicated phacoemulsification surgery by using OCTA, a comparative study between healthy and diabetic patients
Description
A prospective study of 30 patients with senile or complicated cataract scheduled to do phacoemulsification surgery in Tanta University Hospital
Two groups will be divided:
- Group (1): Cataract will no diabetic retinopathy
- Group (2): Cataract associated with diabetic retinopathy.
All patients will be subject to Full ophthalmologic examination before the surgery. Imaging will include OCTA. OCTA will be performed using cirrus OCT (Zeiss, Inc., USA). High-quality 6 x 6 mm OCTA macular scans and 3 × 3-mm papillary scan with strong signal-noise ratio with adequate centration on the fovea and optic nerve head respectively will be selected.
Segmentation will be used to evaluate superficial and deep capillary retinal plexus projections in addition to the choriocapillaries. If errors in segmentation were detected, manual correction would be performed. The superficial retinal capillary plexus (SCP) will be delineated with an inner boundary at the internal limiting membrane (ILM) and an outer boundary 10 µm inside the inner plexiform layer (IPL). The deep retinal capillary plexus (DCP) will be segmented with an inner boundary 10 µm inside the IPL and an outer boundary at 10 µm beneath the outer plexiform layer (OPL).
The vessel density metric from enface OCT angiogram will be used as an indicator of macular retinal and papillary perfusion. Vessel density (VD) analysis computes the percentage of area occupied by OCTA detected vasculature in a measured area. Choriocapillaries flow voids will be computed to assess choriocapillaries circulation.
The measurements of the OCTA, axial length, intraocular pressure will be obtained before the phacoemulsification surgery. Optical coherence tomography and IOP measurements will also be obtained 1 week after surgery.
Eligibility
Inclusion Criteria:
- - Presence of a nuclear, cortical cataract or complicated cataract due to diabetic mellitus
- Intraocular pressure (IOP) of 21 mm Hg or lower
- Axial length (AL) between 20.0 mm and 25.0 mm.
Exclusion Criteria:
- Eyes with an AL longer than 25.0 mm or shorter than 20.0 mm,
- IOP higher than 21 mm Hg,
- History of ocular trauma or intraocular surgery, or any abnormal intraocular findings
- Poor OCT-A images because of severe cataracts or unstable fixation
- Any signs of intraoperative or postoperative complications