Changes in the retrobulbar arterial circulation after decrease of elevated intraocular pressure in patients with primary open angle glaucoma

Abstract

Introduction. An altered perfusion of the optic nerve head has been proposed as a pathogenic factor in glaucoma. Objective. To evaluate changes of haemodynamic parameters in the retrobulbar arterial circulation after a decrease of elevated intraocular pressure (IOP) in patients with primary open angle glaucoma (POAG). Methods. Twenty-six patients were examined, 14 men and 12 women, 21 up to 50 years old and 5 below, all with previously diagnosed and treated POAG, and all examined at the Eye Clinic, Clinical Centre of Serbia. IOP was measured both with a Goldmann aplanation tonometer and dynamic contour tonometer. Central corneal thickness was measured with ultrasound pachymeter. Imaging of the retrobulbar arterial circulation by colour Doppler was performed at the Neurology Clinic, Clinical Centre of Serbia. It involved measuring of haemodynamic parameters of the ophthalmic artery, central retinal artery, and posterior ciliary arteries. Peak systolic velocity (PSV) and end-diastolic velocity (EDV) were measured, and resistive index (RI) and pulsatility index (PI) were calculated. Results. Haemodynamic arterial parameters PSV and EDV in the ophthalmic and central retinal artery after decrease of IOP were lower, while RI and PI were higher. In the posterior ciliary arteries PSV, EDV and PI were lower, and RI was higher. Conclusion. Changes of the retrobulbar arterial circulation after elevated IOP in POAG patients are important for approach and treatment, while the role of vascular factors in the supplement of the optic disc neuroretinal rim could be a key for progression backlash of glaucoma and the radix of neuroprotection.Uvod. Poremecena perfuzija glave ocnog zivca je patogenetski faktor kod glaukoma. Cilj rada. Cilj rada bio je da se ustanovi kako se menjaju hemodinamski parametri u retrobulbarnoj arterijskoj cirkulaciji nakon smanjenja povisenog intraokularnog pritiska (IOP) kod pacijenata s primarnim glaukomom otvorenog ugla. Metode rada. Istrazivanje je obuhvatilo 26 ispitanika (14 muskaraca i 12 zena), od kojih je 21 pacijent bio stariji od 50 godina, sa prethodno dijagnostikovanim i lecenim primarnim glaukomom otvorenog ugla. Svi pacijenti su pregledani na Klinici za ocne bolesti KCS. Pored merenja IOP Goldmanovim (Goldmann) aplanacionim tonometrom (GAT), odnosno dinamickim konturnim tonometrom (DCT), ispitanicima je izmerena i centralna debljina roznjace ultrazvucnim pahimetrom. Pregled retrobulbarne arterijske cirkulacije kolor doplerom obavljen je na Klinici za neurologiju KCS. On je obuhvatio hemodinamske promene u oftalmickoj arteriji, centralnoj retinalnoj arteriji i zadnjim cilijarnim arterijama. Posmatrani su sledeci parametri: vrsni sistolni volumen (PSV), zavrsni dijastolni volumen (EDV), indeks rezistencije (RI) i indeks pulsatilnosti (PI). Rezultati. Hemodinamski arterijski parametri PSV i EDV u oftalmickoj i centralnoj retinalnoj arteriji nakon smanjenja IOP su se smanjili, dok su se RI i PI povecali. Kod kratkih zadnjih cilijarnih arterija PSV, EDV i PI su se smanjili, dok se RI povecao. Zakljucak. Promene u retrobulbarnoj arterijskoj cirkulaciji tokom povecanja IOP kod osoba s primarnim glaukomom otvorenog ugla znacajne su za pristup i lecenje, dok uloga vaskularnih faktora u ishrani neuroretinalnog oboda glave ocnog zivca moze biti kljuc u usporavanju progresije glaukoma i osnova neuroprotekcije.