Peripapillary Capillary Network in Methanol Induced Optic Neuropathy


Purpose: To present the optical coherence tomography angiography (OCTA) findings of the radial peripapillary capillary (RPC) network in an individual with severe bilateral methanol-induced toxic optic neuropathy (MTON) in comparison to a normal subject and a patient with retinitis pigmentosa.

Case Report: A 35-year-old man with severe bilateral MTON was referred to the neuro-ophthalmology clinic at the Labbafinejad Medical Center. The Angio Vue OCT 3D set of 4.5 × 4.5 mm was used to measure the disc and peripapillary vessel density. Two subjects were examined with the same protocol as controls to determine the effect on the RPC vessel density in multiple scenarios. One of the controls was a healthy individual with the prerequisite matches of age and sex while the second one was a known retinitis pigmentosa (RP) patient. RPC density was measured as 37.7 in the patient with MTON, 46.9 in the RP patient, and 54.7 in the healthy control.

Conclusion: The reduction in the RPC vessel density in a patient with MTON compared to that of a healthy individual and also a patient with RP may be due to the loss of capillaries secondary to the loss of nerve fibers and ganglion cells. Moreover, MTON can be considered an optic neuropathy with direct mitochondrial damage to the endothelial cells of the capillaries.


Methanol-induced Toxic Optic Neuropathy, Optical Coherence Tomography Angiography, Radial Peripapillary Capillary Network

1. Massoumi G, Saberi K, Eizadi-Mood N, Shamsi M, Alavi M, Morteza A. Methanol poisoning in Iran, from 2000 to 2009. Drug Chem Toxicol 2012;35:330–333.

2. Pakravan M, Sanjari N. Erythropoietin treatment for methanol optic neuropathy. J Neuroophthalmol 2012;32:325–328.

3. Nurieva O, Diblik P, Kuthan P, Sklenka P, Meliska M, Bydzovsky J, et al. Progressive chronic retinal axonal loss following acute methanol-induced optic neuropathy: four-year prospective cohort study. Am J Ophthalmol 2018;191:100–115.

4. Akil H, Falavarjani KG, Sadda SR, Sadun AA. Optical coherence tomography angiography of the optic disc; an overview. J Ophthal Vis Res 2017;12:98.

5. Falavarjani KG, Tian JJ, Akil H, Garcia GA, Sadda SR, Sadun AA. Swept-source optical coherence tomography angiography of the optic disk in optic neuropathy. Retina 2016;36:S168–S77.

6. Pakravan M, Esfandiari H, Sanjari N, Ghahari E. Erythropoietin as an adjunctive treatment for methanolinduced toxic optic neuropathy. Am J Drug Alcohol Abuse 2016;42:633–639.

7. Sharma S, Ang M, Najjar RP, Sng C, Cheung CY, Rukmini AV, et al. Optical coherence tomography angiography in acute non-arteritic anterior ischaemic optic neuropathy. Br J Ophthalmol 2017;101:1045–1051.

8. Chen JJ, AbouChehade JE, Iezzi Jr R, Leavitt JA, Kardon RH. Optical coherence angiographic demonstration of retinal changes from chronic optic neuropathies. Neuroophthalmology 2017;41:76–83.

9. Mastropasqua R, Borrelli E, Agnifili L, Toto L, Di Antonio L, Senatore A, et al. Radial peripapillary capillary network in patients with retinitis pigmentosa: an optical coherence tomography angiography study. Front Neurol 2017;8:572.

10. Zhang T, Xiao W, Ye H, Chen R, Mao Y, Yang H. Peripapillary and macular vessel density in dysthyroid optic neuropathy: an optical coherence tomography angiography study. Invest Ophthalmol Vis Sci 2019;60:1863–1869.

11. Pellegrini F, Prosdocimo G, Papayannis A, Cirone D. Optical coherence tomography angiography findings in deficiency optic neuropathy. Neuroophthalmology 2019;43:401–406.

12. Takayama K, Ito Y, Kaneko H, Kataoka K, Ra E, Terasaki H. Optical coherence tomography angiography in Leber hereditary optic neuropathy. Acta Ophthalmol 2017;95:e344–e345.

13. Chiong M, Cartes-Saavedra B, Norambuena-Soto I, Mondaca-Ruff D, Morales PE, García-Miguel M, et al. Mitochondrial metabolism and the control of vascular smooth muscle cell proliferation. Front Cell Dev Biol 2014;2:72.

14. Jia Y, Wei E, Wang X, Zhang X, Morrison JC, Parikh M, et al. Optical coherence tomography angiography of optic disc perfusion in glaucoma. Ophthalmology 2014;121:1322– 1332.

15. Liesivuori J, Savolainen H. Methanol and formic acid toxicity: biochemical mechanisms. Pharmacol Toxicol 1991;69:157–163.

16. Pan BX, Ross-Cisneros FN, Carelli V, Rue KS, Salomao SR, Moraes-Filho MN, et al. Mathematically modeling the involvement of axons in Leber’s hereditary optic neuropathy. Invest Ophthalmol Vis Sci 2012;53:7608–7617.

17. Spaide RF, Klancnik JM, Cooney MJ. Retinal vascular layers imaged by fluorescein angiography and optical coherence tomography angiography. JAMA Ophthalmol 2015;133:45–50.