8 research outputs found
FRAME BY FRAME ANGIOGRAPHY
Volume monografia in lingua italiano/ inglese per il 78\ub0congresso S.O.I del 18-21 novembre 199
Arterio-venous transit time in the superficial layer of the optic nerve head: A new parameter of glaucomatous damage
Purpose:To evaluate arterio-venous transit time (AVTT) of the superficial layer of the optic nerve head (ONH) in primary open angle glaucoma (POAG).
Methods:Circulation times of the superficial layer of the ONH were quantified - in 35 POAG and 35 age-matvhed controls - using an objective, electronic guided examination of a high speed dynamic fluorescein angiography. AVTT of the superficial layer of the ONH was compared between groups, and vs ONH morphology and visual field defects.
Results: AVTT of the superficial layer of the ONH was significantly: higher in POAG patients vs controls ( 2.28 vs 1.29 sec; p< .001), and related to ONH morphology and field defects.
Conclusion: AVTT of the superficial layer of the ONH may be exactly quantified and may represent a new, objective parameter of glaucomatous damage
TECNICHE DI DIGITALIZZAZIONE DELLE IMMAGINI APPLICATE ALLO S.L.O
ATTI DEL 10\uc2\ub0 CONVEGNO S.O.
MALATTIA DI VON GIERKE ASPETTI FLUOROANGIOGRAFICI CON S.L.O
ATTI DEL 10\uc2\ub0CONVEGNO SO
Frame by frame dilution analysis of ICG angiography: a new method to measure choridal blood flow in glaucoma
Purposes: To identify a new method of choroidal blood flow analysis in glaucomatous
patients. Methods: Twenty-four glaucomatous patients (G), 15 subjects with normal
tensional glaucoma (NTG) and 26 age-matched controls were recruited for the study.
They were submitted to dynamic indocyanine green angiography (ICGA) with a scanning
laser ophthalmoscope (SLO) (Rodenstock, Munchen, Germany). The choroidal filling
phases were digitized and stored in a computer. Twenty-five frames per second were
obtained. Each frame was elaborated by means of a “ threshold technique ” in order to
obtain black or white pixels. The area occupied by the white pixels in a field of 35° of
the choroid surrounding the disc was measured. The data obtained from each frame
were plotted versus time in order to obtain a “ frame-by-frame ” dilution curve. The 10%
filling time and the 55% filling time were compared among the three groups. Results:
NTG and G groups showed a significantly delayed filling time of the posterior choroid
when compared to the controls (10% filling time, p<0.01; 55% filling time, p<0.05). No
statistical difference between NTG and G could be observed. Conclusions: These data
suggest that an altered choroidal blood flow can play a role in the pathogenesis of
glaucoma.
CR: None -