Abstract
Purpose: :
Silicone oil has been widely used as a long-term tamponade in patients following vitrectomy. A well documented side-effect of this agent is its capacity to migrate outside the vitreous cavity into areas such as the anterior chamber, subconjunctival plane and even cerebral ventricles. The authors present OCT findings in a consecutive series of patients with a history of silicone oil tamponade. The results of this pilot study are used to hypothesise that intraretinal migration of silicone oil occurs in a proportion of these patients.
Methods: :
A retrospective review of all patients who had silicone oil tamponade for retinal detachment at our institution over a 2-year period was conducted. Patients with poor quality or incomplete scan data post-silicone oil removal were excluded. The spectral domain OCT (SD-OCT) images for the remaining patients were reviewed and compared with clinical findings. Results were correlated with features such as duration of silicone oil tamponade and number of previous vitreo-retinal procedures for recurrent retinal detachment.
Results: :
9 patients were included in this study and 5 patients (4 male, 1 female) were positive for intraretinal silicone oil bubbles at the macula on clinical examination. These patients showed corresponding, isolated, intraretinal cystic spaces with SD-OCT which were consistent with intraretinal migration of silicone oil. The mean duration of tamponade was 5.9 months (3.7 months in the 4 patients negative for intraretinal silicone oil) and the timing of OCT ranged from 3 to 18 months post-oil removal. The median number of vitreo-retinal procedures prior to oil removal was 3 in patients with intraretinal oil (1 in negative patients).
Conclusions: :
Patients who have had silicone oil tamponade can show characteristic intraretinal spaces using SD-OCT, corresponding with the clinical appearance of silicone oil bubbles at the macula, after removal of silicone oil. To our knowledge this is the first OCT series to document these findings. The authors hypothesise that intraretinal oil migration could be a contributing factor to poor visual outcome. Prospective studies are needed to further evaluate these findings. In particular, to confirm whether this has a demonstrable effect on macular function and vision and determine the ideal interval for oil removal in these cases.
Keywords: vitreoretinal surgery • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • imaging/image analysis: clinical