Alterations of lacrimal sac vasculature in lacrimal disorders: Chromo endoscopic assessment with changes in effective spectral response.

Purpose: To study the structural and dynamic alterations in the lacrimal sac vasculature of patients with congenital, primary, and secondary acquired nasolacrimal duct obstructions (CNLDO, PANDO, SANDO) and patients with acute dacryocystitis (AD) and failed dacryocystorhinostomy (DCR).

Methods: A prospective study was performed on 65 consecutive lacrimal sacs following their complete exposure during endoscopic dacryocystorhinostomy. High magnification chromo endoscopy and changes in effective spectral response was achieved using the Storz professional image enhancement system (SPIES®). Structural characteristics studied include vascular arrangement, superficial and deep vessels, vessel calibers on cut section, abnormal branching, localized and generalized dilatations and pathologies like varices. Flow characteristics in different caliber vessels and their alterations were assessed in Spectra A mode of SPIES®.

Results: Distinct vascular alterations were noted in several lacrimal disorders. Vascular dilatations differed between the fundus and the body segments of the lacrimal sac, except in cases of traumatic SANDO and prior failed DCRs. 23% (7/30) of PANDO sacs showed peri sac varices and severe tortuosity. The flow in the dilated vessels was either very slow or showed intermittent backflow. Moderate dilatation of peri sac venous plexus with distinct surface linear vessels was noted in CNLDO. The cut surface of the sac wall and luminal surface differentially demonstrated several vascular patterns like speckled, scattered, branched loops, and skip areas in various diseased states.

Conclusion: The present study found distinct alterations of lacrimal sac vasculature in several lacrimal drainage disorders and provides impetus to the vascular theory for pathogenesis of PANDO.