Background: Retinal hamartoma is a common finding in tuberous sclerosis, but the symptomatic changes of this lesion have rarely been described. This evidence-based review evaluated the incidence of symptomatic retinal hamartoma and compared possible treatment modalities.
Methods: We carried out a review of the literature using MEDLINE. Older publications not listed in MEDLINE were obtained from the reference list of currently published papers.
Results: Three observational case series with a follow-up of up to 34 years included 93 patients and reported progression from a flat to a more elevated lesion without visual symptoms in nine patients (9.7%). Additional symptomatic changes were described in 11 case reports published over a period of three decades. The symptomatic alterations were caused by an enlarged tumour with leakage, macular oedema, accumulating lipoid exudates, serous retinal detachment (n = 8/11) and vitreous haemorrhage (n = 4/11). Most symptomatic cases involved a retinal hamartoma type 1 (n = 6/8). Spontaneous resolution of symptomatic exudative hamartomas occurred in three patients within 4 weeks, although a delayed resorption of subretinal fluid caused permanent visual impairment in one patient. Investigational reports described a slow resorption of subretinal fluid after argon laser photocoagulation (n = 2), although recurrent laser applications induced choroidal neovascularization and destruction of the neurosensory retina (n = 1). A vitrectomy was used to remove a vitreous haemorrhage in another reported patient. In one case, complete resorption of subretinal fluid and an increase in visual acuity was observed within 2 weeks after a single treatment with photodynamic therapy (PDT). No complications were noted during a follow-up of 4 years.
Conclusions: Symptomatic changes are very rare in retinal hamartomas secondary to tuberous sclerosis. Spontaneous resolution of subretinal fluid may occur within 4 weeks. If a macular oedema with increasing lipoid exudates persists over a period of 6 weeks, treatment should be considered. Although previous reports demonstrated possible visual stabilization after argon laser photocoagulation, vision-threatening complications can occur. Current treatment strategies may include PDT based on favourable anatomical and functional results.