Bahamas Vision Centre and Princess Margaret Hospital, Nassau NP, Bahamas.
Department of Ophthalmology, Jamaica Hospital Medical Center, New York Medical College, Jamaica, NY, USA.
Surv Ophthalmol. 2022 Mar-Apr;67(2):463-487. doi: 10.1016/j.survophthal.2021.06.004. Epub 2021 Jun 25.
Sildenafil citrate, a selective oral phosphodiesterase 5 inhibitor, is a widely used drug for erectile dysfunction that acts by elevating cGMP levels and causing smooth muscle relaxation. It also has 10% activity against PDE6, a key enzyme in phototransduction cascade in the retina. Recent ocular imaging developments have further revealed the influence of sildenafil on ocular hemodynamics, particularly choroidal perfusion. Choroidal thickness is increased, and choroidal perfusion is also enhanced by autoregulatory mechanisms that are further dependent on age and microvascular abnormalities. Studies demonstrating high intraocular pressure via a "parallel pathway" from increased choroidal volume and blood flow to the ciliary body have challenged previous concepts. Another new observation is the effect of sildenafil on bipolar cells and cyclic-nucleotide gated channels. We discuss potential deleterious effects (central serous chorioretinopathy, glaucoma, ischemic optic neuropathy, and risks to recessive carriers of retinitis pigmentosa), potential beneficial effects (ameliorate choroidal ischemia, prevent thickening of Bruch membrane, and promote recovery of the ellipsoid zone) in macular degeneration, as well as potential drug interactions of sildenafil.
枸橼酸西地那非是一种选择性的口服磷酸二酯酶 5 抑制剂，是一种广泛用于治疗勃起功能障碍的药物，通过提高 cGMP 水平和引起平滑肌松弛起作用。它对视网膜光转导级联中的关键酶 PDE6 也有 10%的活性。最近的眼部成像发展进一步揭示了西地那非对眼血液动力学的影响，特别是脉络膜灌注。脉络膜厚度增加，脉络膜灌注也通过自动调节机制增强，而自动调节机制进一步依赖于年龄和微血管异常。通过增加脉络膜体积和血流到睫状体的“并行途径”来证明高眼压的研究挑战了以前的概念。另一个新的观察结果是西地那非对双极细胞和环核苷酸门控通道的影响。我们讨论了潜在的有害影响（中心性浆液性脉络膜视网膜病变、青光眼、缺血性视神经病变和视网膜色素变性隐性携带者的风险）、潜在的有益影响（减轻脉络膜缺血、防止 Bruch 膜增厚和促进椭圆体带的恢复）在年龄相关性黄斑变性以及西地那非的潜在药物相互作用。
