Utility of laser speckle flowgraphy in screening for carotid-cavernous fistula

Laser speckle flowgraphy (LSFG) offers a non-invasive, accessible means to evaluate ocular blood flow. A case of a woman in her 70s presenting with 6 months of ocular injection following cataract surgery is presented in this report. LSFG measurements indicated lower mean blur rate (MBR) values in the affected eye compared with the healthy eye, though a decrease was also noted in the healthy eye. Subsequent MRI/magnetic resonance angiography revealed an abnormally high signal in the right cavernous sinus, along with a dilated right superior ophthalmic vein, suggesting a carotid-cavernous fistula (CCF). The patient underwent transvenous embolisation under general anaesthesia at the neurosurgery department, successfully occluding the shunt point and eliminating abnormal venous flow. After successful transvenous embolisation, MBR values improved bilaterally. This case highlights LSFG's potential as a simple, non-invasive screening tool for CCF, underscoring the need for further research to confirm its diagnostic utility.