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The Incidence, Characteristics, Management, Prognosis and Classification of Breakthrough Vitreous Hemorrhage Secondary to Polypoidal Choroidal Vasculopathy.

PURPOSE
To describe breakthrough vitreous hemorrhage (VH) secondary to polypoidal choroidal vasculopathy (PCV).


METHODS
Patients with the diagnosis of PCV from January 2005 to March 2020 at Peking Union Medical College Hospital were retrospectively reviewed, cases with breakthrough VH were analyzed. Subgroup analysis was conducted regarding pachychoroid PCV and non-pachychoroid PCV.


RESULTS
Among 722 PCV patients (834 eyes), 103 eyes with breakthrough VH (12.4%) were included. Pars plana vitrectomy (PPV) and proper further interventions could significantly improve the best corrected visual acuity (BCVA) from logMAR 2.15±0.48 (Snellen 20/2825) to 1.65±0.67 (20/893). Hemorrhagic retinal detachment (RD), baseline central macular thickness (CMT) and BCVA were factors associated with final BCVA (P<0.05). In the pachychoroid PCV group, patients were younger, all had hemorrhagic pigment epithelial detachment (PED), with a higher prevalence of choroidal vascular hyperpermeability and hemorrhagic RD, thicker subfoveal choroidal thickness and thinner CMT; besides, the initial PPV were more complicated, more additional surgeries had to be performed. More eyes in the non-pachychoroid PCV group had received anti-VEGF or photodynamic therapy, mostly fibrovascular PED, the BCVA and the status of the fellow eye were significantly worse. For the final ocular status, more eyes in non-pachychoroid PCV group were taking anti-VEGF monotherapy, while more eyes in pachychoroid PCV group were stable. The choroidal parameters of these two groups were all significantly different.


CONCLUSION
Breakthrough VH is a troublesome complication of PCV. PPV and additional interventions are required for better prognosis. VH secondary to pachychoroid PCV or non-pachychoroid PCV have different characteristics and prognosis.