Segmentation of microcystic macular edema in Cirrus OCT scans with an exploratory longitudinal study

Emily K Swingle1, Andrew Lang2, Aaron Carass3

  • 1Department of Biomedical Engineering, The Ohio State University.

Insights

Microcystic macular edema (MME) detection in optical coherence tomography (OCT) scans is improved with a new random forest algorithm. This method accurately identifies MME in lower quality scans, aiding in patient prognosis.

Area of Science:

  • Ophthalmology
  • Medical Imaging
  • Neurology

Background:

  • Microcystic macular edema (MME) presents as pseudocystic spaces in the retina's inner nuclear layer (INL).
  • MME is associated with multiple sclerosis (MS) and other diseases, but its formation and progression are poorly understood.
  • Accurate MME identification and quantification are crucial for patient prognoses due to its low occurrence across diverse conditions.

Purpose of the Study:

  • To develop and validate an automated method for detecting MME in optical coherence tomography (OCT) scans, particularly in lower signal-to-noise ratio (SNR) images.
  • To adapt existing MME identification algorithms for use with Cirrus OCT scans, expanding their applicability.
  • To investigate the longitudinal changes of MME in patients with neurological conditions.

Main Methods:

  • A random forest classifier was trained using manual segmentation of MME in ten subjects.
  • The algorithm was specifically adapted to process lower quality Cirrus OCT scans, building upon prior work with Spectralis OCT.
  • A preliminary longitudinal study tracked MME changes in three patients over 4-5 years.

Main Results:

  • The automated MME detection algorithm achieved a true positive rate of 0.95 and a Dice score of 0.79.
  • The method successfully identified MME in lower quality Cirrus OCT scans.
  • Longitudinal analysis indicated dynamic pseudocyst volumes in patients with relapsing-remitting MS and neuromyelitis optica, contrasting with stable MME volume in a primary progressive MS patient.

Conclusions:

  • The developed random forest classifier provides an effective and automated approach for MME detection in OCT scans, even in lower quality images.
  • This advancement facilitates more consistent quantification of MME, supporting improved patient prognoses.
  • Preliminary longitudinal data suggest distinct MME progression patterns based on MS subtype and related neurological conditions.

Related Concept Videos