TABLE 3B.

Functional change in related to disc torsion.

References	Sample size	Mean age (mean ± SD) (years)	Follow-up	Image	Definitions of disc tilt and disc torsion	Main findings
Cross-sectional
Hung et al. (95)	100 Myopic eyes of 50 patients with POAG	50.1 ± 10.0	–	Fundus photograph	Disc tilt: ratio of disc diameter = longest/shortest Disc torsion: deviation of the longest axis of the optic disc from the perpendicular meridian.	For the same patient, eyes with VF defect has greater degree of optic disc rotation than the fellow eyes without VF defect. Greater degree of optic disc rotation was significantly associated with the presence of VF defects (multivariate logistic regression analysis).
Kim et al. (96)	105 Myopic eyes with OAG	52.81 ± 11.69	–	Fundus photograph	Disc tilt: ratio of disc diameter = longest/shortest Disc torsion: deviation of the longest axis of the optic disc from the perpendicular meridian.	The artificial neural networks identified PPA area, peripapillary RNFL thickness, disc-foveal angle, and disc torsion degree as significant variables in OAG with myopia
Park et al. (97)	225 NTG eyes with or without myopia	Myopic NTG: 42.85 ± 11.81 Non-myopic NTG: 60.73 ± 11.43	–	Fundus photograph	Disc tilt: ratio of disc diameter = longest/shortest Disc torsion: deviation of the longest axis of the optic disc from the perpendicular meridian.	Torsion degree was the only factor related to VF defect location.
Choi et al. (90)	136 Glaucomatous patients and 99 normal controls	Glaucoma: 54.3 ± 13.8 Control: 52.9 ± 5.5	–	Fundus photograph, OCT	Disc tilt: ratio of disc diameter = longest/shortest. Tilt direction: Temporal disc tilt: angle between a horizontal line and the line connecting the disc margin. Vertical disc tilt: angle between the vertical line and the line connecting the disc margin. Disc torsion: deviation of the longest axis of the optic disc from the perpendicular meridian.	Eyes with superior hemifield defects exhibited higher degree of disc torsion and higher proportion of inferiorly torsional disc than eyes with inferior hemifield defects.
Park et al. (10)	134 Myopic eyes with NTG	Without staphyloma: 49.78 ± 8.68 With staphyloma: 50.16 ± 12.06	–	OCT, Fundus photograph	Disc tilt: ratio of disc diameter = longest/shortest Disc torsion: deviation of the longest axis of the optic disc from the perpendicular meridian.	Ten eyes (71.4%) from the inferior staphyloma group had superior VF defects, and five eyes (71.4%) from the superior staphyloma group had inferior VF defects. When the posterior staphyloma involved the optic disc, extensive disc enlargement with less disc torsion appeared.
Park et al. (24)	78 NTG and 78 POAG patients (matched axial length and age)	POAG 56.16 ± 13.98 NTG 54.96 ± 14.54	–	OCT	Tilt angle: ONH vertical and horizontal tilt were measured from a B-scan passing through the 6 to 12 o’clock and 3 to 9 o’clock position, respectively. Disc torsion: deviation of the longest axis of the optic disc from the perpendicular meridian.	Myopic NTG eyes showed greater torsion degree than non-myopic NTG eyes (the POAG eyes did not show this finding). NTG eyes showed a significant difference in the degree of maximum tilt and torsion and the direction of vertical tilt and torsion by the location of visual field defect.
Longitudinal
Han et al. (100)	97 Myopic eyes with NTG	53.8 ± 13.7	71.1 ± 29.7 months	Fundus photograph	Disc tilt: ratio of disc diameter = longest/shortest Disc torsion: deviation of the longest axis of the optic disc from the perpendicular meridian.	Myopic NTG eyes with disc tilt direction <45° had higher cumulative probability of progression than eyes with tilt direction ≥45°.
Baek et al. (106)	108 POAG eyes (single- hemifield defect at initial VF examination)	Progression sparing of opposite hemifield: 55.7 ± 10.7 Progression involvement of opposite hemifield: 61.0 ± 10.5	7.9 ± 3.0 years	Fundus photograph	Disc tilt: ratio of disc diameter = longest/shortest Disc torsion: deviation of the longest axis of the optic disc from the perpendicular meridian. The presence of vertical tilt: angle of vertical tilt was < -15° or > + 15°.	Absence of optic disc vertical tilt (HR = 1.430; P = 0.017) were risk factors for the involvement of the opposite hemifield. Younger age and presence of optic disc vertical tilt showed greater cumulative probability of sparing the opposite hemifield.
Sung et al. (107)	92 Myopic eyes with NTG	37.83 ± 10.89	55.78 ± 30.12 months	Fundus photograph	Disc tilt: ratio of disc diameter = longest/shortest. Disc torsion: deviation of the longest axis of the optic disc from the perpendicular meridian.	Optic disc rotation and VF defect correspondence (HR, 0.441; P = 0.016) were associated with VF progression in myopic NTG eyes.
Kim et al. (102)	56 Myopic eyes with NTG	Stable group: 46.75 ± 11.24 Progression group: 47.00 ± 10.83	72.63 ± 20.46 months	Fundus photograph	Tilt angle: angle between the disc margin plane and BMO plane. Temporal tilt: positive degree of horizontal tilt. Nasal tilt: negative degree of horizontal tilt. Disc torsion: deviation of the longest axis of the optic disc from the perpendicular meridian.	The vertical tilt angle (HR = 0.835, P = 0.026) and the DPE positioned temporal to the fovea (HR = 4.314, P = 0.001) were associated with VF progression.
Kwun et al. (98)	66 Myopic eyes with NTG	46.62	93.74 months	Fundus	Disc tilt: ratio of disc diameter = longest/shortest Disc torsion: deviation of the longest axis of the optic disc from the perpendicular meridian.	The greater optic disc tilt and torsion in myopic eyes with NTG were not associated with VF progression.
Na et al. (108)	102 Myopic eyes with POAG	57.17 ± 10.43	73.21 ± 12.81 months	Fundus photograph	Disc tilt: ratio of disc diameter = longest/shortest Disc torsion: deviation of the longest axis of the optic disc from the perpendicular meridian	Eyes with VF defect corresponded to the disc torsion direction has faster VF progression than eyes without disc torsion or with disc torsion direction not corresponded to VF defect.
Han et al. (109)	82 OAG eyes without myopia and 150 OAG eyes with myopia	Non-myopic OAG: 46.0 ± 11.4 Myopic OAG: 45.6 ± 12.0.	Non-myopic OAG: 10.0 ± 2.4 years Myopic OAG: 9.8 ± 2.7 years	Fundus photograph	Disc tilt: disc diameter ratio = longest/shortest Disc torsion: deviation of the longest axis of the optic disc from the perpendicular meridian. Inferiorly tilted disc: torsional angle >15°. Temporally tilted disc: torsional angle ≤15°.	The cumulative probability of progression was faster for myopic OAG with inferiorly tilted disc compared with temporally tilted disc and non-myopic OAG. Inferiorly tilted disc was predictive of progression (HR = 2.378; P < 0.001). In the analysis of myopic OAG with inferiorly tilted disc, the progression group had younger age and earlier-stage VF defect at baseline compared with the stationary group.
Park et al. (26)	100 Myopic eyes with POAG	50.1 ± 10.0	Progression to NTG: 71.83 ± 9.81 months Non-progression to NTG: 67.18 ± 6.13 months	Fundus photograph	Disc tilt: ratio of disc diameter = longest/shortest Disc torsion: deviation of the longest axis of the optic disc from the perpendicular meridian.	Greater disc torsion was one of the risk factors for NTG suspects to convert to NTG. In subgroup analysis, greater disc torsion was a significant risk factor only for myopic NTG suspects.

POAG, primary open angle glaucoma; VF, visual field; OAG, open angle glaucoma; PPA, peripapillary atrophy; NTG, normal tension glaucoma; OCT, optical coherence tomography; ONH, optic nerve head; HR, hazard ratio; BMO, Bruch’s membrane opening; DPE, deepest point of eyeball; OAG, open angle glaucoma.