Monte Carlo simulation of diabetic macular edema changes on optical coherence tomography data

Abstract

Optical coherence tomography (OCT) scans were acquired from healthy controls and patients with diabetic macular edema (DME), a common complication of diabetes characterized by increased retinal thickness due to fluid accumulation. The collected OCT data was divided into three distinct groups: healthy subjects, DME patients with significantly increased outer nuclear layer (ONL) thickness and DME patients without visible changes in the ONL. For each group, the ONL was segmented and processed, yielding a representative A-scan. Using reference values for the physical and optical characteristics of the healthy human retina, we used a Monte Carlo method with a model for the ONL to simulate an A-scan for each group and compare it to the real OCT data. This allowed to identify which alterations in the cellular characteristics are responsible for the changes observed in the OCT scans of the diseased groups.

Application of different imaging modalities for diagnosis of Diabetic Macular Edema: A review

“…However, SD-OCT findings revealed 42.1% of these cases have no ME. Hence, SD-OCT findings can be used as adjunct tool for DME screening Magdy et al [69] 13 ✓ Â Â OCT thickness map is correlated with FA leakage pattern and reported a highest correlation coefficient of 0.9086 Querques et al [63] 63 Â ✓ ✓ CMT is increased for NCSME ð294:5 7 23:5 μmÞ and CSME ð385:6 7 75:1 μmÞ compared with normal ð272:57 16:2 μmÞ subjects Regatieri et al [61] 49 Â Â ✓ SD-OCT findings show that subfoveal choroidal thickness is thinner ð63:3 μmÞ for DME patients Roychowdhury et al [70] 120 Â Â ✓ Cyst in DME class is segmented automatically using OCT images and reported a correlation rate of 90% Correia et al [66] 24 Â Â ✓ Increased ONL thickness is observed between normal and DME classes Dmuchowska et al [56] 51 ✓ ✓ ✓ There is no significant correlation between foveal avascular zone size and RT measured using OCT. Hence, OCT cannot replace the FA for ischemic DME…”

“…Features are extracted using logarithmic space, linear space and exponential distribution from the OCT images and SVM classifier and reported an accuracy of 84.2%. Correia et al [66] used HD-OCT to analyse normal, Outer Nuclear Layer (ONL) thickness changes in patients with DME. Initially, manual segmentation of ONL is performed.…”

“…Initially, manual segmentation of ONL is performed. Further, segmented ONL is modelled using Monte Carlo method to generate A-scan data which showed pathological changes of ONL due to changes in the cellular characteristics [66]. Kang et al [67] used OCT to assess correlation between OCT features and FA in patients with CSME.…”

Retracted: Early diabetic retinopathy diagnosis based on local retinal blood vessels analysis in optical coherence tomography angiography (OCTA) images

“…Many studies are conducted to analyze the retinal blood vessels and layers to help ophthalmologists diagnose different retinal diseases. Most of these studies are based on analyzing the colored fundus images, 1,7,8,9,10,11,12,13,14 optical coherence tomography (OCT) scans, 15,16,17,18,19 and OCTA scans. 20,21,22 In the remaining part of this section, we discuss the CAD systems based on these three imaging modalities.…”

“…They also localized cysts for DME patients. Correia et al 17 detected the variations that occurred in the outer nuclear layer (ONL) in DME cases. A Monte Carlo algorithm with a model for the ONL is utilized to simulate an A-scan for two groups of healthy and diseased subjects to detect the changes.…”