Optical Coherence Tomography Angiography Assessment of Retinal Lesions in Inflammatory Bowel Diseases

Optical Coherence Tomography Angiography Assessment of Retinal Lesions in Inflammatory Bowel Diseases

Aim of the study;To record the vascular changes that may be present in the posterior segment of patients suffering from Inflammatory bowel diseases(IBD) using the optical coherence tomography angiography

a prospective study of 30 patients suffering from IBD referred from tropical department from Tanta University Hospital

-Patients demographic data e.g., sex, age, concomitant systemic diseases will be recruited. Presenting symptoms, physical examination results, laboratory and imaging findings, and received treatment of IBD will be recorded. Accurate grading of disease severity will be carried out by gastroenterology specialist.

All patients will be subject to Full ophthalmologic examination and fundus imaging. Imaging will include OCTA and fundus photography. 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 and 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

Inclusion Criteria:

• Patients with Crohn's disease and ulcerative colitis either newly diagnosed or suffering from chronic disease on treatment will be included

Exclusion Criteria:

• Recent ophthalmological surgery.

  • Low quality ophthalmological exams.
  • Refractive errors greater than + 3 or - 3 spherical.
  • Retinopathies such as diabetic retinopathy.
  • Any type of retinal degenerations or retinal dystrophy.