LETTER TO THE EDITOR
Anisocoria: Realities, Recognition, and Remedial Aspects
1Department of Emergency and Critical Care, Manian Medical Centre, Erode, Tamil Nadu, India
2Department of Emergency Medicine, Meenakshi Mission Hospital and Research Centre, Madurai, Tamil Nadu, India
3Department of Neuroscience, SIMS Chellum Hospital, Salem, Tamil Nadu, India
4Department of Emergency Medicine, Dr Moopen’s Wayanad Institute of Medical Sciences, Meppadi, Kerala, India
5Department of Internal Medicine, Trichy SRM Medical College Hospital and Research Centre, Irungalur, Tiruchirapalli, Tamil Nadu, India
Corresponding Author: Subramanian Senthilkumaran, Department of Emergency and Critical Care, Manian Medical Centre, Erode, Tamil Nadu, India, Phone: +91 9994634444, e-mail: email@example.com
How to cite this article Senthilkumaran S, Jena NN, Balamurugan N, Florence B, Thirumalaikolundusubramanian P. Anisocoria: Realities, Recognition, and Remedial Aspects. IJCCM 2019;23(11):543.
Source of support: Nil
Conflict of interest: None
The realities, recognition, and remedial aspects of anisocoria at the bedside were highlighted by Adhikari et al.,1 which is almost similar to an earlier report from India.2 Since this condition involves patient safety and clinical assessment, we would like to touch upon 3 Ps (physiological, pathological, and pharmacological) of anisocoria. First and foremost is to elicit a thorough clinical history and then to assess the case in detail which not only rules out injuries, infections, instillation, or ingestion of medicines and instigating mechanisms but also helps rule out various other life-threatening conditions.
Keywords: Nebulization, Nebulizer, Palsy.
The realities, recognition, and remedial aspects of anisocoria at the bedside were highlighted by Adhikari et al.,1 which is almost similar to an earlier report from India.2 Since this condition involves patient safety and clinical assessment, we would like to touch upon 3 Ps (physiological, pathological, and pharmacological) of anisocoria.
First and foremost is to elicit a thorough clinical history and then to assess the case in detail which not only rules out injuries, infections, instillation, or ingestion of medicines and instigating mechanisms but also helps rule out various other life-threatening conditions. Also, look for pupillary response to near focus, eyelid position, and eye movements, which brings out third nerve involvement and stresses on the need to review the cases in detail. One has to consider the pathological and pharmacological causes of anisocoria at the bedside before embarking any statement and/or giving assurances to the patients and/or care givers.
Pharmacologically, pilocarpine causes constriction of normal pupil; however, in a patient presenting with dilated pupil and a history of chronic topical sympathomimetic use, the pharmacologic testing with pilocarpine can complicate the diagnosis. This is because it has no direct antagonistic effect since it is not a sympatholytic drug. Moreover, in botulinum toxin poisoning, administration of 1% pilocarpine does constrict a toxic-dilated pupil because presynaptic inhibition of acetylcholine release by the neurotoxin. Prominent anisocoria in dark indicates underlying pathology in the small pupil due to disease-affecting sympathetic system.3 Though pilocarpine test helps differentiate anisocoria prominent in bright light, apraclonidine test4 is suggested for prominent anisocoria in dim illumination.
Thus to summarize, one has to examine the eye in detail including pupils especially if confronted with anisocoria, and to check for pupillary status in dim light and bright illumination5 so as to elicit and interpret the physiological response, recognize the pathological conditions, and intervene with appropriate pharmacological agents or other remedial measures. The old adage “simple solutions for complex problems” holds good with anisocoria.
1. Adhikari SD, Chakrabortty R, Kerai SI, Budoo MS. An elementary cause of aniscoria in intensive care unit. Indian J Crit Care Med 2019;23(7):346. DOI: 10.5005/jp-journals-10071-23213.
2. SenthilKumaran S, Balamurugan N, Suresh P, Thirumalaikolundusubramanian P. Transient anisocoria: a pesky palpitation. J Neurosci Rural Pract 2011;2(2):210–211. DOI: 10.4103/0976-3147.83606.
3. Senthilkumaran S, Balamurugan N, Menezes RG, Thirumalaikolundusubramanian P. Bedside test for anisocoria: not a small matter. Indian J Crit Care Med 2014;18(7):480–481. DOI: 10.4103/0972-5229.136084.
4. Koc F, Kavuncu S, Kansu T, Acaroglu G, Firat E. The sensitivity and specificity of 0.5% aproclonidine in the diagnosis of oculosympathetic paresis. Br J Ophthalmol 2005;89(11):1442–1444. DOI: 10.1136/bjo.2005.074492.
5. Senthilkumaran S, Karthikeyan N, Jena NN, Florence B, Thirumalaikolundusubramanian P. Anisocoria and diagnostic application of pilocarpine—an eye opener. Am J Emerg Med 2019;37(8):1586–1587. DOI: 10.1016/j.ajem.2019.05.029.
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