Purpose: Ocular and brain microcirculation share embryological and histological similarities. The retinal vascular fractal dimension (FD) is a marker of retinal vascular complexity of the vascular tree. The purpose of this study was to explore the relationship between cerebral blood flow (CBF), retinal vascular FD and other retinal vascular markers. Methods: Cross-sectional analysis comprising 26 individuals ≥65 years old from the Cognitive REServe and Clinical ENDOphenotype (CRESCENDO) cohort of relative healthy older adults. Retinal vascular FD was measured from fundus photographs by using the semi-automated Singapore Eye Vessel Assessment (SIVA) software. CBF was estimated using a 2D pulsed ASL MRI sequence. Associations between blood flow and retinal parameters were analysed using linear regression models adjusted for age and sex. Results: Cerebral blood flow was positively associated with venular FD (R 2 = 0.32, p = 0.03). This association was stronger in the anterior versus posterior brain territories (R 2 = 0.35 [p = 0.001] versus R 2 = 0.16 [p = 0.07], respectively). Global CBF was correlated with arteriolar branching angle (R 2 = 0.23, p = 0.01) and tortuosity (R 2 = 0.20, p = 0.02). Global CBF was not correlated with other SIVA parameters. Conclusions: Retinal venular complexity summarized by the FD was associated with cerebral blood flow as well as retinal arteriolar tortuosity and branching angle. Larger prospective clinical studies are needed to confirm these results.

Pourfour du Petit syndrome is an uncommon cause of eyelid retraction, associated with unilateral mydriasis and hemifacial hyperhidrosis. This syndrome is caused by hyperactivity of the ipsilateral oculosympathetic pathway and needs to be recognized because it has an opposite clinical presentation but the same topographic and diagnostic value as Horner syndrome. The authors report a rare case of Pourfour du Petit syndrome associated with cluster headache and discuss pathophysiological hypotheses, clinical presentation, complementary exams, pharmacologic testing, treatment options, and prognosis. Early detection of these symptoms may lead to swift diagnosis and treatment.

Evisceration with autogenous scleral grafting and ceramic implantation can result in a high volume of restoration, good cosmetic results, and low risk of exposure of the implant.

Purpose The retinal vascular fractal dimension (FD) is a marker of retinal complexity of vascular tree. It has been associated with neurodegenerative and cerebrovascular diseases. Arterial spin labelling is a non‐invasive technique to evaluate the cerebral blood flow (CBF). The purpose of this study was to explore the relationship between retinal vascular FD and CBF. Methods Cross sectional analysis comprising 29 individuals aged 65 years and over from the Cognitive REServe and Clinical ENDOphenotype (CRESCENDO) cohort of healthy older adults. Retinal vascular FD was measured from fundus photographs using semi‐automated standardized imaging software “Singapore Eye Vessel Assessment (SIVA)” system. CBF was estimated in various gray matter regions from a 2D Pulsed arterial spin labelling sequence from MRI. Results A higher venular FD was associated with higher CBF in all cerebral regions of interest (p < 0.01). No significant associations were found between CBF and other parameters derived from SIVA or the central retinal arterial or venular equivalent. This association was stronger for opposite eye to handedness (p = 0.03). No relationship was observed between arterial FD and CBF (p > 0.07). Conclusions Venular FD was the main parameter associated to cerebral perfusion whereas retinal vascular calibers were not. It may be evaluated in clinical studies for early and non‐invasive detection of subclinical cerebro‐vascular pathologies including dementia and stroke.