Čmelo J, Illéš R, Šteňo J
Cesk Slov Oftalmol. 2017 Summer;73(2):57-60.
The value of ICT is important in diagnosis of the diseases of the eye and orbit Methods for direct measurement of intracranial pressure (ICT) are exact, but they are invasive and there is some risk of infection and damage of the tissue. Currently there are 2 valid indirect methods of mesurement of IKT. Digital Ophthalmodynamometry (D-ODM) and Transcranial Doppler ultrasonography (TDU). D-ODM is a non-invasive method for measuring of the Pulsating Venous Pressure (VPT). We can measure VPT by the pulse phenomena. Physiologically (to be maintained blood flow) VPT not be less than the ICT and intraorbital pressure (IorbitT). If we raise the VPT to compensate the current IKT (or IorbitT) - there is a pulsation VCR. We can calculate aproxymative IKT with the formula: IKT = 0.903 - (VPT) - 8.87, or IKT = 0.29 + 0.74 (VOT / PI (AO)). [VOT = intraocular pressure. PI - pulsatility index arteriae ophthalmic from Color Doppler ultrasonography.] IKT can be approximate calculate with mathematical formulas: IKT = 0:55 × BMI (kg / m2) + 0.16 × KTD (mmHg) - 0:18 x age (years) - 1.91. [KTD - diastolic blood pressure, BMI - Body master index] or: IKT = 16.95 x 0.39 x OSASW09 + BMI + 0.14 + TKS - 20.90. [OSASW095: width of the orbital arachnoid space at a distance of 9 mm behind the eyeball (nuclear magnetic resonance). BMI: Body Mass Index. TKS: mean arterial pressure]. Normal values of VPT are under 15 torr. The risk of increased intracranial pressure is above 20 torr. Under physiological conditions, there is intraocular pressure lower in about 5 torr than VPT.
D-ODM is a useful screening method in the evaluation of IKT for hydrocephalus, brain tumors, cerebral hemorrhage after brain trauma and also in ocular diseases: Glaucoma, Ocular hypertension, orbitopathy (endocrine orbitopathy), ischemic / non-ischemic occlusion of blood vessels of the eye, indirect detection ICT carotid artery-cavernous fistula, amaurosis fugax, optic neuropathy. D-ODM is suitable for immediate evaluation of IKT, but is not suitable for continuous monitoring. As it can be repeated, it is useful for a patient suspected of having an increased ICT.Key words: central retinal artery, central retinal vein, colour Doppler ultrasonography, digital ophthalmodynamometry, intracranial pressure, pressure of cerebrospinal fluid, transcranial Doppler ultrasonography, intraocular pressure, venous pulsation pressure, venous outflow pressure, retinal venous pressure.
颅内压（ICT）的数值在眼部和眼眶疾病的诊断中很重要。直接测量颅内压的方法准确，但具有侵入性，存在一定的感染和组织损伤风险。目前有两种有效的间接测量ICT的方法。数字眼压描记法（D - ODM）和经颅多普勒超声检查（TDU）。D - ODM是一种测量搏动静脉压（VPT）的非侵入性方法。我们可以通过脉搏现象测量VPT。生理上（为维持血流），VPT不应低于ICT和眶内压（IorbitT）。如果我们提高VPT以补偿当前的ICT（或IorbitT），就会出现VCR搏动。我们可以用公式计算近似的ICT：ICT = 0.903 -（VPT）- 8.87，或ICT = 0.29 + 0.74（VOT / PI（AO））。[VOT =眼压。PI - 彩色多普勒超声检查得出的眼动脉搏动指数。] ICT可以用数学公式近似计算：ICT = 0.55×BMI（kg / m²）+ 0.16×KTD（mmHg）- 0.18×年龄（岁）- 1.91。[KTD - 舒张压，BMI - 身体质量指数] 或：ICT = 16.95×0.39×OSASW09 + BMI + 0.14 + TKS - 20.90。[OSASW095：眼球后9mm处眶蛛网膜下腔宽度（核磁共振）。BMI：身体质量指数。TKS：平均动脉压]。VPT的正常值低于15托。颅内压升高的风险高于20托。在生理条件下，眼压比VPT低约5托。
D - ODM是评估脑积水、脑肿瘤、脑外伤后脑出血以及眼部疾病（青光眼、高眼压症、眼眶病（内分泌性眼眶病）、眼部血管的缺血性/非缺血性阻塞、间接检测ICT颈动脉海绵窦瘘、一过性黑矇、视神经病变）的ICT时有用的筛查方法。D - ODM适用于ICT的即时评估，但不适用于连续监测。由于它可以重复，对于怀疑ICT升高的患者很有用。关键词：视网膜中央动脉、视网膜中央静脉、彩色多普勒超声检查、数字眼压描记法、颅内压、脑脊液压力、经颅多普勒超声检查、眼压、静脉搏动压、静脉流出压、视网膜静脉压。
