Consider cotton wool spots as potential triggers for (non-glaucomatous) nerve fibre bundle defects
April 13, 2025

Consider cotton wool spots as potential triggers for (non-glaucomatous) nerve fibre bundle defects

It may be tempting to make a glaucoma diagnosis in the presence of a nerve fibre bundle defect with or without visual field defect when located in the temporal-superior or temporal-inferior sector and when accompanied by elevated intraocular pressure in a diabetic patient. “Glaucoma-like” RNFL defects can, however, also be caused by other pathologies. For instance, there is a well-documented association of (non-glaucomatous) localized RNFL defects with preceding cotton wool spots in case series and case reports (1,2), and with their underlying systemic diseases (i.e. diabetes, arterial hypertension etc.) in cross-sectional and retrospective studies (3,4). Of note, these scenarios are complicated by the heavily studied, yet poorly understood and controversially discussed epidemiological link between diabetes and POAG.(5,6) Therefore, in such cases comprehensive clinical investigation and close follow-up are of special importance to prevent overtreatment on one hand and minimize risk of missing a glaucoma diagnosis on the other hand.


References

  1. Alencar LM, Medeiros FA, Weinreb R. Progressive localized retinal nerve fiber layer loss following a retinal cotton wool spot. Semin Ophthalmol. 2007;22(2):103–4.
  2. Koh JW, Park KH, Kim MS, Kim JM. Localized retinal nerve fiber layer defects associated with cotton wool spots. Jpn J Ophthalmol. 2010 Jul;54(4):296–9.
  3. Zhao L, Wang YX, Zhang W, Zhang JS, Chen CX, Xu L, et al. Localized retinal nerve fiber layer defects detected by optical coherence tomography: the Beijing eye study. PloS One. 2013;8(7):e68998.
  4. Baek J, Jung Y, Ohn K, Jung SY, Oh SE, Moon JI. Association between localized retinal nerve fiber layer defects in nonglaucomatous eyes and metabolic syndrome: a propensity score-matched analysis. Ann Transl Med. 2023 Jun 30;11(9):316.
  5. Kjærsgaard M, Grauslund J, Vestergaard AH, Subhi Y. Relationship between Diabetic Retinopathy and Primary Open-Angle Glaucoma: A Systematic Review and Meta-Analysis. Ophthalmic Res. 2022;65(4):377–86.
  6. Chauhan MZ, Elhusseiny AM, Kishor KS, Sanvicente CT, Ali AA, Sallam AB, et al. Association of Primary Open-Angle Glaucoma with Diabetic Retinopathy among Patients with Type 1 and Type 2 Diabetes: A Large Global Database Study. Ophthalmology. 2024 Jul;131(7):827–35.


Contributor: Martin Kallab MD, Linz, Austria

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