Fractal analysis of fluoroangiographic patterns in anterior ischaemic optic neuropathy and optic neuritis: a pilot study

Traversi, Claudio; Bianciardi, Giorgio; Tasciotti, Annalisa; Berni, Elisa; Nuti, Elisabetta; Pietro, Luzi; Tosi, Gian Marco

doi:10.1111/j.1442-9071.2008.01766.x

Cited by 21 publications

(17 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…2008). We documented a mean D f of 1.444 in the optic disc field of the retina in this study, which is smaller than previously reported mean D f (1.708 by Daxter and 1.63 by Traversi) (Daxer 1993b; Traversi et al. 2008).…”

Section: Discussioncontrasting

confidence: 89%

“…Retinal vascular fractal measurement (D f ) is a potential early marker of changes in microvascular structure and could be an indicator of major ocular and systemic disease (Daxer 1993a; Liew et al. 2008; Traversi et al. 2008).…”

Section: Discussionmentioning

confidence: 99%

“…The discrepancies of D f measurement are likely related to the different protocols used for fractal measurement. We measured D f on monochrome photographs by the box‐counting method, whereas other studies used fluorescein fundus angiography (Daxer 1993b; Traversi et al. 2008) or calculated D f by a density–density correlation method (Daxer 1993b; Traversi et al.…”

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

Lens opacity and refractive influences on the measurement of retinal vascular fractal dimension

Liew

Rochtchina

et al. 2010

Acta Ophthalmologica

View full text Add to dashboard Cite

ABSTRACT.Purpose: To examine the influence of lens opacity and refraction on the measurement of retinal vascular fractal dimension (Df). Methods: Optic disc photographs (right eyes) of 3654 baseline Blue Mountains Eye Study participants (aged 49-97 ) were digitized. Retinal vascular Df was quantified using a computer-based program. Summated severity scores for nuclear, cortical and posterior subcapsular (PSC) cataract were assessed from lens photographs. Refraction data were converted to spherical equivalent refraction (SER), as sum spherical plus 0.5 cylinder power. Axial length was measured at 10-year follow-up examinations using an IOL master. Results: Mean Df of the retinal vasculature was 1.444 ± 0.023 for 2859 eligible participants. Increasing lens opacity scores were associated with significant reduction in Df (b = )0.0030, p < 0.0001). Both cortical and PSC cataract involving central lens area were associated with reduced Df, after controlling for confounding factors (p trend £ 0.0105). Increasing myopia severity was associated with reduced Df after adjusting for lens opacity scores and other confounders (p trend < 0.0001). The slope of Df decrease per SER reduction was 0.0040 in eyes with SER £ )4D, compared to )0.0016 in eyes with SER > )4D. For axial length quintiles, there were no significant differences in mean Df in all groups except a reduction in the fifth quintile (axial length ‡24.15 mm) (all p < 0.05). Conclusion: Ocular media opacity independently influenced retinal vascular Df measurement, but we found no evidence supporting any refractive axial magnification effect on this measure. Myopic refraction £)4D was associated with a reduction in Df, suggesting rarefaction of retinal vasculature associated with high myopia.

show abstract

Section: Discussioncontrasting

confidence: 89%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Lens opacity and refractive influences on the measurement of retinal vascular fractal dimension

Liew

Rochtchina

et al. 2010

Acta Ophthalmologica

View full text Add to dashboard Cite

show abstract

“…These results add also new information to previous data obtained by us, where another fractal index, geometrical complexity evaluated by local box-counting analysis, resulted able to distinguish between the pathologies [37].…”

Section: Discussionsupporting

confidence: 66%

Mass Dimension Evaluation of the Optic Nerve Head Microvascularity in Non-Glaucomatous Optic Neuropathies

Bianciardi¹

2016

Int J Oral Craniofac Sci

View full text Add to dashboard Cite

In several diseases, fractal analysis has been proven useful to give contribution in diagnosis and prognosis of the patient and to improve treatments. In the present work we have evaluated the mass dimension of the vascular pattern of optic nerve head in non-glaucomatous optic neuropathic patients and healthy controls. Static fluorescein angiogram was performed and the images of the early venous phase were saved. A manual outline of the trajectories of the two-dimensional vascular network was performed down to vessels of 20 micron diameter, processed to threshold the vessel network without background interference and converted into an outline of single pixels and then the fractal analysis was performed. Mass dimension evaluation of the optic nerve head microvascularity was able to differentiate health condition vs. non-glaucomatous neuropathies (p<0.01), as well optic neuritis vs. nonarteritic anterior ischemic optic neuropathy (p<0.01), with high sensitivity and specificity (p<0.0001; p<0.0001). Mass dimension index shows a significantly increased vascular complexity of the optic nerve head in cases compared with controls, also permitting to distinguish between patients affected by optic neuritis vs. nonarteritic anterior ischemic optic neuropathy. This new, fast, unexpensive, methodology may be used in helping the clinician to perform the differential diagnosis between the pathologies and to study the effect of therapies during the follow up of the patient.(NAION) is difficult to be performed on clinical grounds, both giving overlapping clinical profiles [15]. However, it is fundamental to establish an early differential diagnosis, having the ON patient a clear tendency to develop multiple sclerosis, a disease where therapies should be performed as early as possible [16]. In order to verify whether the fractal analysis of the optic nerve head microvascularity could help in the differential diagnosis between ON and NAION, we have evaluated the mass dimension of the optic nerve head vascular pattern, as revealed by fluorescein angiography. SubjectsPatients with unilateral NAION or unilateral idiopathic ON were recruited from the Department of Ophthalmology of the University of Siena. Each patient underwent a complete neuro-ophthalmic examination, including assessment of visual acuity, colour vision, papillary reaction, slit-lamp examination, applanation tonometry, Goldman visual field testing, visual evoked potentials, dilated fundoscopy and fluorescein angiogram.The criteria for patients' admittance with NAION to the study were: unilateral disc swelling with clinical features consistent with NAION [16], no recovery of visual function in the first month of follow up, exclusion of arteritic anterior ischemic optic neuropathy either on clinical grounds or following a negative temporal artery biopsy, negative magnetic resonance imaging of the brain and orbits, no other ocular pathology, no neurological diseases that might influence or explain the patient's visual symptoms. The patient admittance criteria wi...

show abstract

“…One consequence of increased lesion volumes (edema) would be that edema related compression leads to transient preservation of the vasculature. This conclusion garners support in cases of retinal edema with increased fractal dimensions 46,47 . Alternatively, increased peak fractal frequency in cases with increased lesion volume are consistent with potentially increased fragmentation of the vascular network, as might be observed after TBI, particularly with increased lesion volumes.…”

Section: Discussionsupporting

confidence: 52%

Traumatic brain injury results in acute rarefication of the vascular network

Obenaus

Orantes

et al. 2017

Sci Rep

View full text Add to dashboard Cite

The role of the cerebrovascular network and its acute response to TBI is poorly defined and emerging evidence suggests that cerebrovascular reactivity is altered. We explored how cortical vessels are physically altered following TBI using a newly developed technique, vessel painting. We tested our hypothesis that a focal moderate TBI results in global decrements to structural aspects of the vasculature. Rats (naïve, sham-operated, TBI) underwent a moderate controlled cortical impact. Animals underwent vessel painting perfusion to label the entire cortex at 1 day post TBI followed by whole brain axial and coronal images using a wide-field fluorescence microscope. Cortical vessel network characteristics were analyzed for classical angiographic features (junctions, lengths) wherein we observed significant global (both hemispheres) reductions in vessel junctions and vessel lengths of 33% and 22%, respectively. Biological complexity can be quantified using fractal geometric features where we observed that fractal measures were also reduced significantly by 33%, 16% and 13% for kurtosis, peak value frequency and skewness, respectively. Acutely after TBI there is a reduction in vascular network and vascular complexity that are exacerbated at the lesion site and provide structural evidence for the bilateral hemodynamic alterations that have been reported in patients after TBI.

show abstract

Fractal analysis of fluoroangiographic patterns in anterior ischaemic optic neuropathy and optic neuritis: a pilot study

Abstract: Our data suggest that eyes with ON and NAION seem to have increased vascular complexity in the optic nerve head, manifested as an increase in fractal dimension.

Cited by 21 publications

References 34 publications

Lens opacity and refractive influences on the measurement of retinal vascular fractal dimension

Lens opacity and refractive influences on the measurement of retinal vascular fractal dimension

Mass Dimension Evaluation of the Optic Nerve Head Microvascularity in Non-Glaucomatous Optic Neuropathies

Traumatic brain injury results in acute rarefication of the vascular network

Contact Info

Product

Resources

About