Positional Intraocular Pressure of Vitrectomized and Normal Fellow Eyes

Abstract

PurposeTo compare posture-induced intraocular pressure (IOP) changes in vitrectomized eyes and normal eyes of patients who had vitrectomy in one eye.MethodsA total of 31 patients older than 20 years of age who underwent vitrectomy were enrolled in the study. At least six months after vitrectomy, we measured IOP in both eyes using a rebound tonometer 10 minutes after the patient assumed sitting, supine, right lateral decubitus, and left lateral decubitus positions. Patients with a history of ocular surgery (not including vitrectomy) or recent medication use associated with IOP were excluded. IOP and ocular parameters of vitrectomized and normal fellow eyes were compared. For the decubitus position, IOP values of dependent and nondependent eyes were compared.ResultsNo significant difference was observed in IOP between vitrectomized and normal eyes in the sitting and supine positions. The IOP for dependent eyes (on the lower side in the lateral decubitus position) was significantly higher than the IOP for nondependent eyes in both right lateral decubitus (right vitrectomized eye 19.31 ± 4.20 vs. 16.71 ± 4.02 mmHg, p < 0.001; left vitrectomized eye 18.35 ± 1.75 vs. 16.04 ± 3.02 mmHg, p = 0.003) and left lateral decubitus (right vitrectomized eye 17.32 ± 4.63 vs. 19.15 ± 3.83 mmHg, p = 0.004; left vitrectomized eye 16.19 ± 1.81 vs. 18.12 ± 2.29 mmHg, p < 0.001) positions.ConclusionsIOP was higher in the dependent than the nondependent eye in the lateral decubitus position, for both vitrectomized and nonoperated eyes.

Intraocular Pressure Rise Linked to Silicone Oil in Retinal Surgery: A Review

“…There is evidence that elevated levels of hydrogen peroxide and free radicals after vitrectomy may cause damage to trabecular meshwork cells [ 64 , 65 ]. Moreover, the filling of the vitreous cavity with a substance other than the vitreous could affect the structural and physiological stability of the eye [ 66 ]. The contact of SO with a trabecular meshwork already impaired from the recent surgery may trigger an inflammatory reaction leading to OH in the early phase and to an established glaucoma in the long term.…”

Pars Plana Vitrectomy and the Risk of Ocular Hypertension and Glaucoma: Where Are We?

“…A further caveat refers to the notion that intraocular pressure changes also according to head and eye position, as posturing is often required after PPV surgery: IOP in the most dependent eye increases significantly after posturing [ 25 ]. This assumes importance in spine surgery for example, when the patient may be postured with tamponated eye in a dependent position, often face down or on a lateral decubitus occasionally reported as cause of ischemic optic nerve damage [ 26 ].…”