Aberrant Anterior Thalamic Radiation Structure in Bipolar Disorder: A Diffusion Tensor Tractography Study

Area of Science:

• Neuroimaging
• Neuroscience
• Psychiatry

Background:

• White matter (WM) integrity disruptions in the anterior thalamic radiation (ATR) are linked to bipolar disorder (BD).
• Diffusion tensor tractography (DTT) is a neuroimaging technique used to visualize WM structure.

Purpose of the Study:

• To investigate the feasibility of visually evaluating structural WM aberrations in the ATR using DTT.
• To determine if ATR visualization quality can differentiate individuals with BD from healthy controls (HCs).

Main Methods:

• The study included 114 participants: 57 with BD and 57 HCs.
• ATR fiber bundles were assessed for visualization quality using DTT.
• Fractional anisotropy (FA) values were analyzed to establish an optimal threshold for distinguishing between good and poor ATR visualization.

Main Results:

• Poor ATR visualization was significantly more frequent in the left ATR of individuals with BD compared to HCs (P = 0.042).
• An optimal FA threshold of 0.28 in the right ATR allowed for classification of BD and HCs with 71.1% accuracy (AUC = 0.76).

Conclusions:

• Visual evaluation of ATR integrity using DTT shows potential as an adjunctive diagnostic tool for BD.
• The optimal FA threshold derived from DTT may serve as a biological marker for distinguishing individuals with BD from HCs.