Abstract
Abstract: :
Purpose: To study possible causes for the following phenomenon: we observed a number of patients with abnormally adherent silicone oil (SiO). In such patients SiO had been in contact with perfluorocarbon liquid (PFLC) peroperatively but this PFLC had always been removed by a direct exchange to SiO at the end of the surgery. In most patients, sticky remnants of a viscous gel-like substance were found at the time of SiO removal surgery; in some, however, the sticky substance developed during the PFLC/SiO exchange procedure. Methods: Charts of consecutive patients in whom SiO and PFCL had been used intraoperatively during 2001, were reviewed to identify possible factors that predispose to sticky SiO formation. Gas Chromatography-Mass Spectroscopy (GC-MS) and MRI analyses were performed on sticky SiO samples and compared with PFCL and SiO samples obtained after uneventful removal. Results: Chart review revealed an occurrence of sticky SiO in 27 out of 150 SiO removal procedures between April and October 2001. Sticky oil remnants were seen on the surface of the retina and were difficult to remove. In four patients the remnants caused postoperative visual disturbance; in three patients our attempts at forced removal had caused complications. Although we had made no attempt at a double filling of SiO and PFCL in any patient, results of the analyses of the sticky oil samples indicate the presence of PFO (octane: C8F18). Although both PFO and PFD (decaline: C10F18) were used in 2001, sticky oil was only encountered in PFO cases. GC-MS analyses revealed partially fluorinated carbon liquid to be present in the "normal" PFO samples and not in the PFD samples. Conclusions: Although sporadic similar cases have been reported, in our study we are able to analyze possible clinical factors. The occurrence of abnormally adherent SiO seems surgeon related: a variation in surgical technique, such as the pressure gradient during PFCL/SiO exchange may be important. The interaction between SiO and PFCL could occur over time if PFCL is not removed completely when SiO is injected, but in some cases the phenomenon was even observed during SiO injection. Impurities in PFCL and or SiO could result in increased interaction between the two an the development of sticky oil.
Keywords: vitreoretinal surgery • clinical (human) or epidemiologic studies: ris