TY - JOUR
T1 - Agreement between optical coherence tomography and digital stereophotography in vertical cup-to-disc ratio measurement
AU - Savini, Giacomo
AU - Espana, Edgar M.
AU - Acosta, Ana Carolina
AU - Carbonelli, Michele
AU - Bellusci, Costantino
AU - Barboni, Piero
PY - 2009
Y1 - 2009
N2 - Background: Given the increasing popularity of optical coherence tomography in the diagnosis of glaucoma, we aimed to assess agreement between StratusOCT and stereophotography in measuring the vertical cup-to-disc ratio (VCDR) and examine whether it can be improved by changing the StratusOCT cup-offset. Methods: In group 1 (79 eyes), VCDR measurements obtained by StratusOCT (using the default cup-offset of 150 μm bove the retinal pigment epithelium) and stereophotography were compared. For each eye, the cup-offset was moved upward or downward until the difference disappeared and an adjusted cup-offset was identified. In group 2 (41 eyes), the stereophotography VCDR was compared to the StratusOCT value obtained by using the mean adjusted cup-offset. StratusOCT was used to classify optic disc cups as shallow or deep. Results: In group 1, StratusOCT overestimated VCDR in optic discs with deep cups and underestimated it in those with shallow cups (p <0.0001). Mean adjusted cup-offsets were 72.8±92 μm and 191.6±70 μm for eyes with deep and shallow cups. The 95% limits of agreement (LOA) ranged from -0.21 to 0.17. In group 2, the adjusted cup-offsets enabled us to eliminate the statistical differences in VCDR measurements and improve the 95% LOA (from -0.13 to 0.14). Conclusion: Adjusting the StratusOCT cup-offset according to the cup depth improves agreement between StratusOCT and stereophotography in measuring the VCDR.
AB - Background: Given the increasing popularity of optical coherence tomography in the diagnosis of glaucoma, we aimed to assess agreement between StratusOCT and stereophotography in measuring the vertical cup-to-disc ratio (VCDR) and examine whether it can be improved by changing the StratusOCT cup-offset. Methods: In group 1 (79 eyes), VCDR measurements obtained by StratusOCT (using the default cup-offset of 150 μm bove the retinal pigment epithelium) and stereophotography were compared. For each eye, the cup-offset was moved upward or downward until the difference disappeared and an adjusted cup-offset was identified. In group 2 (41 eyes), the stereophotography VCDR was compared to the StratusOCT value obtained by using the mean adjusted cup-offset. StratusOCT was used to classify optic disc cups as shallow or deep. Results: In group 1, StratusOCT overestimated VCDR in optic discs with deep cups and underestimated it in those with shallow cups (p <0.0001). Mean adjusted cup-offsets were 72.8±92 μm and 191.6±70 μm for eyes with deep and shallow cups. The 95% limits of agreement (LOA) ranged from -0.21 to 0.17. In group 2, the adjusted cup-offsets enabled us to eliminate the statistical differences in VCDR measurements and improve the 95% LOA (from -0.13 to 0.14). Conclusion: Adjusting the StratusOCT cup-offset according to the cup depth improves agreement between StratusOCT and stereophotography in measuring the VCDR.
KW - Glaucoma
KW - Optic nerve
KW - Optical coherence tomography
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U2 - 10.1007/s00417-008-0968-3
DO - 10.1007/s00417-008-0968-3
M3 - Article
C2 - 18958489
AN - SCOPUS:59749093254
VL - 247
SP - 377
EP - 383
JO - Graefe's Archive for Clinical and Experimental Ophthalmology
JF - Graefe's Archive for Clinical and Experimental Ophthalmology
SN - 0721-832X
IS - 3
ER -