Sub-inner limiting membrane haemorrhage: causes and treatment with vitrectomy

Background: Preretinal haemorrhages usually occur at the interface between the posterior hyaloid and inner limiting membrane (ILM). Less frequently, they are located between the ILM and the retinal nerve fibre layer. Sub-ILM haemorrhages have been described in a variety of clinical settings and often lead to severe visual impairment because of their predilection for the macular region. Methods: A consecutive series of five cases in which sub-ILM haemorrhages were clinically suspected and confirmed during early vitrectomy with ILM peeling were reviewed. Results: Sub-ILM haemorrhages were clinically suspected in five patients (median age 32 years) based on the fundoscopic appearance and clinical setting of Terson’s syndrome (n = 1), Valsalva retinopathy (n = 2), blood dyscrasia (n = 1) and blunt facial trauma (n = 1). Vision was severely impaired in all patients (to hand movements in four of five) because of a premacular location of the haemorrhage. All patients were treated with early pars plana vitrectomy because of insufficient spontaneous visual recovery after a median of 6 weeks. The sub-ILM location of the haemorrhage could be confirmed intraoperatively in all patients by biostaining of the membrane overlying the haemorrhage. ILM peeling and aspiration of the haemorrhage resulted in excellent visual recovery in all patients. No procedure-related complications were observed. Conclusions: Sub-ILM haemorrhages often occur in a specific clinical context and can lead to severe visual impairment in young patients. Given the excellent results and low complication rates, timely surgical intervention is justified when spontaneous resorption is insufficient.