Glaucoma | 青光眼
- Primary glaucoma | 原发性青光眼
- Primary open-angle glaucoma, POAG | 原发性开角青光眼
- Primary angle closure glaucoma, PACG | 原发性闭角青光眼
- Secondary glaucoma | 继发性青光眼
IOP
- 眼压是青光眼发生发展的最重要危险因素
- 降眼压是目前唯一获得证实的可以减缓青光眼疾病进展和保留视功能的治疗方法
- 眼压和眼压测量仍是青光眼诊断与治疗中最基本、最重要的指标
- 较高的眼内压及 MD 导致较高的失明风险
Intraocular pressure 与 blood pressure 的关系
参考文章：Ocular perfusion pressure and glaucoma: clinical trial and epidemiologic findings
眼灌注压表示为动脉血压与眼内压差值
Perfusion pressure | 灌注压
The normal functioning of tissues depends on the maintenance of an adequate perfusion, with sufficient blood flow. A key element is the presence of an ample perfusion pressure to meet tissue needs, a process that requires a balance between arterial and venous blood pressure (BP).
人体组织器官需要足够的血流量才能正常工作，血流量与灌注压直接相关。
Ocular perfusion pressure, OPP | 眼灌注压
参考：The Role of Ocular Perfusion Pressure in Glaucoma
OPP 定义为眼内动脉压与静脉压差值。眼内静脉压接近 IOP，因此可使用 IOP 进行近似，代替静脉压：
$$ OPP = arterial \ BP - IOP $$
但动脉压要复杂一些，动脉压由心脏跳动产生，存在收缩压（systolic BP）、舒张压（diastolic BP）和平均血压的概念，因而引入了三个计算公式：
$$ Systolic \ OPP \ (SPP) = Systolic \ BP - IOP $$
$$ Diastolic \ OPP \ (DPP) = Diastolic \ BP - IOP $$
$$ Mean \ OPP \ (MPP) = \frac{2}{3} \times [diastolic \ BP + \frac{1}{3} \times (systolic \ BP - diastolic \ BP)] - IOP $$
Low OPP 是青光眼的明确危险因素
Low DPP is a risk factor for glaucoma.
— Jeffrey Liebmann, MD
已在统计学上建立了 BP 与 IOP 关系
Many studies have reported a positive, statistically significant relationship between blood pressure (BP) and IOP, which is consistent across studies and stronger for systolic than for diastolic BP. Additionally, BP often explains a larger proportion of the variation in IOP than other known variables, although the percent explained is relatively small, about 5%. For systolic BP, estimates from cross-sectional studies suggest that each 10 mmHg higher BP is associated with a 0.23−0.32 mmHg higher IOP. Similar estimates, of 0.21 and 0.22mmHg higher IOP, have been derived from longitudinal data in the Beaver Dam and Barbados studies. Results for diastolic BP are less consistent.
关键点：
- BP 与 IOP 在统计学上呈正相关；
- BP 是已知能解释 IOP 变化的最显著变量；
- 收缩压与 IOP 相关性强于舒张压；
- 收缩压每升高 10 mmHg，眼压上升 0.2 - 0.3 mmHg；
OPP 与 IOP 的联系有待研究
The transient IOP fluctuations (IOP minus IOP baseline) are positively correlated with the ocular perfusion pressure (mean blood pressure minus IOP)
OPP 与 IOP 波动成正相关，这个是显然的。
A low ocular perfusion pressure could be due to a relatively low BP or a relatively high IOP. Neither of these variables, alone, has been implicated conclusively as the sole cause of low perfusion in glaucoma. As discussed in a later section, there is no clear relationship between BP levels and OAG damage.
高 IOP 或低 BP 都可以得到低 OPP，但这个看起来有点类似鸡生蛋的问题。