MODELING OF SILICONE OIL EMULSIFICATION FOR POSTERIOR RETUNAL TAMPONADE

Serhienko A. N., Tkachuk K. K., Serhienko V. V.

CLINICAL AND EXPERIMENTAL MEDICINE

Scentific article

We reproduced a model of silicone oil interaction with intraocular fluids using an emulsion of silicone oil and balanced salt solution (SO-BSS) of different concentrations (10.0%, 20.0%, 33.3%, 50%, and 66.7% of SO). To bring together the results of simulations and clinical practice, we used the data of 23 patients who had passed s surgery for rhegmatogenous retinal detachment using a 1300 cST viscosity Oxane silicone oil and physicochemical indicators of the silicone oil retrieved from the post-tamponade patients. The density of model systems was measured by a pycnometric method with due account to adjustment for a body weight loss in the air (0.00129 g/cm3). We measured the relative viscosity of the model systems by the viscometry method using Ostwald capillary viscometer. The studies were carried out at a temperature of 20.00 ± 0.05°С. The special DOXYMOD.exe Console Application developed on the basis of C++ programming language in the Microsoft Visual Studio 2008 environment using the ALGLIB mathematical library was applied for calculations and selection of adequate mathematical models for describing revealed experimental dependencies. Depending on the oil phase density of the silicone oil in aspirated samples, the patients were divided into 4 groups: Group 1 – d20 = 0.9700-0.9799 g/cm3; Group 2 – d20 = 0.9800-0.9981 g/cm3; Group 3 – d20 = 0.9982-1.0049 g/cm3; and Group 4 – d20 = 1.0050-1.0100 g/cm3. We compared a degree of silicone oil emulsification with a number of post-surgery complications. Ocular hypertension and development of proliferative vitreoretinopathy were taken as the complications associated with silicone tamponade. In the course of physico-chemical simulation of the SO-BSS binary system, we found that the density of the model system had a linear dependence on the volume fraction of the balanced salt solution. We proposed a densimetric mathematical model to determine a degree of silicone oil emulsification after continuous contact with the intraocular fluid. It consisted of two coupled equations and allowed, within an interval of density values of silicone oil aspirated from the patients` eyes, predicting changes of viscosity and a degree of the silicone emulsification after continuous contact with the biological intraocular fluid. Proceeding from the data on SO emulsification in the patients` vitreal cavity under continuous tamponade, we made conclusions on the silicone oil emulsification degree for all group of patients managed by us. 1 – 3% silicone oil emulsification was assessed as safe in terms of complications associated with the silicone oil. We also revealed that 12 – 15% silicone oil emulsification caused a 100% risk of postoperative complications (ocular hypertension and development of proliferative vitreoretinopathy).

silicine oil, emulsification, retinal detachment

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«Bulletin of problems biology and medicine» Issue 4 Part 3 (141), 2017 year, 224-230 pages, index UDK 617.735-007.281-092-079-085

10.29254/2077–4214–2017–4–3–141–224-230