Clinical Trial Details
— Status: Not yet recruiting
Administrative data
NCT number |
NCT05778370 |
Other study ID # |
HBA1c and OCT Macula |
Secondary ID |
|
Status |
Not yet recruiting |
Phase |
|
First received |
|
Last updated |
|
Start date |
April 15, 2023 |
Est. completion date |
December 1, 2023 |
Study information
Verified date |
March 2023 |
Source |
Assiut University |
Contact |
Salma G Nouby, Resident |
Phone |
01124142121 |
Email |
salmanouby[@]gmail.com |
Is FDA regulated |
No |
Health authority |
|
Study type |
Observational
|
Clinical Trial Summary
Diabetic retinopathy (DR) is a frequent cause of visual impairment, and the leading cause of
blindness in those of working age, but it develops silently along years, producing symptoms
only in late stages.
Description:
The risk of sight-threatening consequences can be reduced if the lesions are detected before
irreversible damage to retinal function has developed .Patients with diabetes mellitus (DM)
have many pathological changes in their macula as diabetic macular edema (DME), exudates,
cysts, detachment and ischemia that cause impairment of vision.
DME is characterized by increased vascular permeability and deposition of hard exudates at
the macula and can occur at any stage of DR. With the help of OCT, it is possible to quantify
the macular thickness objectively and to follow the progression of DME quantitatively.
Currently, DME is classified as 'center involved' or 'non center involved' (referring to
whether or not there is oedema i.e., CMT>250 μm at the fovea) based on OCT. Non-centre
involved macular oedema is rarely symptomatic. However, as the oedema spreads to the central
macula, patients usually experience progressive vision loss and treatment with anti-VEGF is
recommended.
Also, DM can cause many pathological changes in the choroid as increased tortuosity, focal
vascular dilatation, microaneurysms and nonperfused areas. Studies have analyzed choroidal
thickness changes in DR using spectral domain optic coherence tomography. A number of studies
have shown that choroidal thickness decreases as the diabetic retinopathy progresses.
Swept-source (SS) OCT is a variation of OCT that offers improvements in visualizing the
vitreous, retina, and choroid at one image. The increased scan speeds, decreased signal
attenuation, more comprehensive imaging, and deeper tissue penetration make SS-OCT ideal for
capturing a wide range of views and studying structures below the retinal pigmented
epithelium (RPE), especially the choroid.
Glycated haemoglobin (HbA1c) is measured primarily to identify the average plasma glucose
concentration over prolonged periods and reflect the long-term control of hyperglycaemia.
Higher levels of HbA1c increase the incidence of DME over a 10-year period in Wisconsin
Epidemiology Study of Diabetic Retinopathy (WESDR). The Diabetes Control and Complication
Trial (DCCT) and the UK Prospective Diabetic Study (UKPDS) both of which were randomized
prospective studies showed that intensive glycaemic control and thus reduction of HbA1c
levels are associated with a decrease in the rates of development and progression of DR and
DME.
The use of HbA1c for the diagnosis of DM has been approved by the WHO based on a number of
epidemiological studies showing that a threshold for increased prevalence of microvascular
complications can be observed at HbA1c level of 6.5% .
Aim of the work To investigate the correlation between HbA1c levels in patients with type II
diabetes mellitus on central macular thickness as well as central choroidal thickness using
swept source optical coherence tomography.