Retinal ischemic perivascular lesions in patients with pulmonary embolism: an OCT angiography study

To investigate the prevalence of retinal ischemic perivascular lesions (RIPL) in pulmonary embolism (PE) patients.

In this retrospective case-control study, 40 eyes from patients with PE and 40 eyes from age-matched healthy controls were examined. Participant RIPL numbers and locations were recorded. Quantitative analysis was conducted for the superficial capillary plexus (SCP) and deep capillary plexus (DCP) in areas where RIPL were detected.

The prevalence of RIPL was higher in the eyes of patients with PE than in the control group (47.5% versus 7.5%, p < 0.001). PE patients had, on average, a higher number of RIPL compared to controls (1.07 versus 0.12, p < 0.001). DCP vessel density (VD) (%) values in the superior (parafovea superior-hemi p = 0.007; perifovea superior-hemi p = 0.038) and inferior (inferior hemi p = 0.037; parafovea inferior-hemi p = 0.029; perifovea inferior-hemi p = 0.032) temporal quadrants, where RIPL are concentrated, were significantly lower. The presence of at least one RIPL in an eye was significantly associated with PE (OR = 8.48; 95% CI: 2.11-34.22; p = 0.011). The prevalence of RIPL (p = 0.592) and the mean number of these lesions (p = 0.249) were similar between patients with recent PE and prior PE.

RIPL are remnants of paracentral acute middle maculopathy (PAMM), known to arise due to heightened vulnerability of the inner nuclear layer to ischemia at the DCP level. This lesion has been associated with chronic ischemia in the retina in many studies. RIPL was more prevalent among patients with PE and was strongly associated with it. These findings suggest an association between PE and subclinical retinal microvascular alterations.