Decreased retinal nerve fibre layer thickness detected by optical coherence tomography in patients with ethambutol-induced optic neuropathy.

Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, 6565 Fannin NC-205, Houston, TX 77030, USA.
British Journal of Ophthalmology (Impact Factor: 2.73). 08/2007; 91(7):895-7. DOI: 10.1136/bjo.2006.113118
Source: PubMed

ABSTRACT It is difficult to assess the degree of optic nerve damage in patients with ethambutol-induced optic neuropathy, especially just after the onset of visual loss, when the optic disc typically looks normal.
To evaluate changes in retinal nerve fibre layer thickness (RNFLT) using optical coherence tomography (OCT) in patients with optic neuropathy within 3 months of cessation of ethambutol treatment.
A retrospective observational case series from a single neuro-ophthalmology practice.
8 patients with a history of ethambutol-induced optic neuropathy were examined within 3 months after stopping ethambutol treatment. All patients underwent a neuro-ophthalmologic examination, including visual acuity, colour vision, visual fields and funduscopy. OCT was performed on both eyes of each patient using the retinal nerve fibre layer analysis protocol.
The interval between cessation of ethambutol treatment and the initial visit ranged from 1 week to 3 months. All patients had visual deficits characteristic of ethambutol-induced optic neuropathy at their initial visit, and the follow-up examination was performed within 12 months. Compared with the initial RNFLT, there was a statistically significant decrease in the mean RNFLT of the temporal, superior and nasal quadrants (p = 0.009, 0.019 and 0.025, respectively), with the greatest decrease in the temporal quadrant (mean decrease 26.5 mum).
A decrease in RNFLT is observed in all quadrants in patients with ethambutol-induced optic neuropathy who have recently discontinued the medication. This decrease is most pronounced in the temporal quadrant of the optic disc.

  • [Show abstract] [Hide abstract]
    ABSTRACT: No drug is absolutely safe. Pharmacovigilance is the science related to detection, assessment, understanding and prevention of adverse effects or any other possible drug-related problems. The ocular medications and devices can cause localized and systemic adverse effects. Not all adverse effects are known when a drug or device is launched in market because of limitations of clinical trials. Many adverse effects are recognized due to the spontaneous reporting of the vigilant doctors who observe and report such events encountered in their practice. Despite a large ophthalmic patient population base, India does not have robust adverse drug reaction (ADR) database because of lack of reporting culture. Government of India recently launched the Pharmacovigilance Programme of India (PvPI) to monitor ADRs and create awareness among the healthcare professionals about the importance of ADRs. Suspecting and reporting a possible drug reaction is very important in developing a safe and rational ophthalmic practice.
    Indian Journal of Ophthalmology 04/2013; · 1.02 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Ethambutol (EMB) is one of the first-line antimycobacterial drugs used to treat tuberculosis and is also used to treat atypical mycobacterium infections. It is almost always used in combination with other antimycobacterial drugs. Ever since the drug’s introduction in the 1960s, there have been descriptions of optic neuropathy associated with EMB. Despite a clear association of EMB-induced optic neuropathy, many questions remain unanswered, namely, which tests are more accurate to monitor toxicity, how often should they be performed and once the optic neuropathy is present, how much of it is reversible?
    Expert Review of Ophthalmology 03/2014; 9(2).
  • Source
    Journal of the Korean Ophthalmological Society 01/2010; 51(8).


Available from