Assessment of retinal, choroidal and peripapillary microvascular changes in patients with chronic myeloid leukemia.

Purpose: To quantitatively assess the microvascular alterations and structural parameters in the optic disc, retina, and choriocapillaris of chronic myeloid leukemia (CML) patients devoid of leukemic retinopathy, while also examining the correlation between these parameters and serum laboratory results.

Study design: Prospective, cross-sectional, observational clinical study METHODS: This study included 30 eyes from 15 patients diagnosed with CML and 30 eyes from age 15- and gender-matched healthy individuals (control group). All participants underwent comprehensive ophthalmologic assessments, including optical coherence tomography angiography (OCTA). Statistical analyses, including Student's t-test and the Mann-Whitney U test, were conducted to compare structural and vascular parameters between CML patients and controls. Spearman's correlation was used to evaluate the relationship between OCTA measurements and serum parameters.

Results: The analysis of macular vessel density revealed significant reductions in all assessed parameters in the patient group compared to the control group. These parameters include whole image superficial vessel density (wisVD, p=0.005), parafoveal superficial vessel density (pfsVD, p=0.002), perifoveal superficial vessel density (pefsVD, p=0.007), whole image deep vessel density (widVD, p=0.005), parafoveal deep vessel density (pfdVD, p=0.004), and perifoveal deep vessel density (pefdVD, p=0.005). Higher white blood cell levels were associated with lower optic nerve head whole image VD, wisVD, pfsVD, pefsVD, widVD, and pefdVD. Higher platelet levels were correlated with lower widVD. Additionally, hemoglobin showed a positive correlation with choriocapillaris vessel flow density, while it exhibited a negative correlation with superior and inferior macular ganglion cell complex thickness.

Conclusion: Subclinical retinal perfusion loss was observed in CML patients, and this perfusion loss was associated with hematological parameters. The marked reduction in macular perfusion could be valuable for understanding the pathogenesis of the disease and predicting potential retinal complications such as hypoxia and ischemia in more advanced stages. Further studies are needed to investigate the functional and prognostic significance of the changes we observed.