Structural and Functional Optic Nerve Changes in Patients on Amiodarone Therapy
Norhan Mohmed Kamal Eldien Youssef, Doaa Maamoun Mohamed Ashour, Emad Effat Shehata, Weam Mohamed Ahmed Ebeid, Amany Abd El-Fattah El-Shazly- General Medicine
Purpose
To investigate the structural and functional optic nerve changes in patients on amiodarone therapy.
Methods
A total of 30 eyes were examined were divided into two groups, study group of patients included (15 eyes) of cardiac patients on amiodarone therapy for more than four consecutive months, and control group included (15 eyes) of age- and sex-matched healthy participants. Both groups have underwent full ophthalmological examination, optical coherence tomography examination for optic nerve head scan, electrophysiological studies included (pattern visual evoked potential).
Results
Electrophysiological studies were the tool for the assessment of the functionality of the ocular structure in our study, the pattern visual evoked potential results have shown to be of no statistically significant difference between the N75 latency (ms) (P-value=0.972), P100 latency (ms) (P-value 0.547) and N75-P100 amplitude (µV) (P-value =0.18), in the numeric values between the control and cases groups. And for qualitative structural assessment we have performed optical coherence tomography scan imaging for the optic nerve head for all the participants in this study, and the results revealed no statistically significant differences in the obtained values regarding NFL thickness map. This agrees with the obtained electrophysiological tests results to be both within normal limits
Conclusion
The current study revealed normal electrophysiological as well as optical coherence tomography measurements in the included sample of patients on chronic amiodarone therapy. All the included patients had good, best corrected visual acuity (BCVA) and none complained of any visual symptoms. None had clinically suspected optic nerve affection and this was confirmed by the detailed imaging and electrophysiological assessment for both macula and optic nerve.