Suprachoroidal Injection of Triamcinolone Acetonide in Resistant Diabetic Macular Edema, CRVO, Pseudophakic Cystoid Macular Edema and Diabetic Macular Edema Following Pars Plana Vitrectomy

• Prospective non randomized interventional study on 60 eyes of 40 patients with previously diagnosed macular edema secondary to type 1 or 2 diabetes mellitus and 60 eyes with central retinal vein occlusion will be included.
• The study will be conducted from January 2021 to June 2021.
• For transition to suprachoroidal injection of Triamcinolone Acetone (TAAC) a diagnosis of resistant DME is required.
• Inclusion criteria:

Patients fulfilling one or more of the following criteria will be considered to have resistant diabetic macular edema (DME) after at least 3 consecutive monthly anti vascular endothelial growth factor (VEGF) injections in the previous 6 months: central macular thickness greater than 300 μm by spectral-domain optical coherence tomography (SD-OCT), reduction of retinal thickness by less than 10% of baseline retinal thickness, or suboptimal visual improvement (failure to gain at least 3 lines on the Snellen chart).

• The subjects included in the research will undergo the following tests and investigations:

1. Visual acuity testing (uncorrected and best corrected).
2. Intra ocular pressure (IOP) by applanation tonometry.
3. Anterior segment examination by slit lamp
4. Posterior segment examination by indirect ophthalmoscope and 78 D lens
5. Spectral domain Optical coherence tomography (OCT).
6. Ocular fundus photography and fluorescein angiography.

• Exclusion criteria will be:

1. Previous intraocular surgery (except cataract surgery done more than 6 months before the study).
2. Coincident retinal pathology as choroidal neovascular membrane and age related macular degeneration.
3. Previous laser photocoagulation.
4. Intravitreal injection of triamcinolone acetonide.
5. Prior ocular inflammation.
6. The presence of retinal degeneration.
7. Patients who didnot complete 6 months of follow up

Injection technique:

Preoperative preparation:

1. Preoperative control of (Diabetes Mellitus)DM is essential before injection.
2. Informed consent was obtained according to the ethical committee after discussing extensively with each patient about the benefits, risks and possible side effects of the procedure .
3. The patient was prepared by topical fluoroquinolone eye drops (Moxifloxacin hydrochloride 0.5% Vigamox ,Alcon, USA) 4 times daily for three days before injection.

All patients were dilated before suprachoroidal injection of Triamcinolone Acetonide (SCTA) and indirect ophthalmoscope was placed at hand to examine fundus after injection.

We used 30 gauge 1cc insulin syringe. Other dispensable included 24 gauge intravenous branula. Needle was withdrawn from branula and branula was cut in such a way that only 1000um of insulin syringe was exposed from the edge of branula. 0.1 ml (4 mg ) of Triamcinolone Acetonide (TAAC) will be injected.

Post operative care:

After the injection topical antibiotic drop was applied (Moxifloxacin hydrochloride 0.5% Vigamox, Alcon, USA) and the eye was patched for several hours.

After surgery patients were instructed to administer antibiotic drop four times daily for 3 days .

• Privacy of the patients must be guaranteed ,the data acquired from the participants will stay confidential through:

1. Putting a code number to every patient, with hiding the patient's name.
2. Photographing faces will not be needed.
3. The results of the research will be only used in scientific aim.

• Any unexpected risks like subconjunctival hemorrhage, syncope, vitreous hemorrhage, retinal detachment and endophthalmitis appeared during the course of the research will be cleared to the participants and the ethical committee on time.

Medical care will be carried out to complications like syncope, subconjunctival hemorrhage and surgical treatment by pars plana vitrectomy will be done in case of occurrence of vitreous hemorrhage, retinal detachment or endophthalmitis.