Adie's tonic pupil after COVID-19: a case report and literature review.

Objective: Various neurological complications have been reported after COVID-19. The study aimed to document an unusual case of Adie's tonic pupil following COVID-19. Methods: The study was a case report. Results: A 28-year-old female had suffered a flu-like disease about 2 months before and the SARSCoV-2 polymerase chain reaction test at that time was positive. Two weeks after infection she noticed an asymmetry between the pupils. The only pathological finding on examination was anisocoria with a larger left pupil in ambient light. Light reflexes were observed in the right eye, while in the left eye, they were absent. Also, there was no near response in the left pupil. A 0.1% pilocarpine test results validated Adie's pupil diagnosis. After one year of follow-up, the anisocoria decreased but did not completely recover. Discussion: COVID-19 may cause damage to neural structures due to autoimmune ways by activating immune pathways or because of vascular complications that may affect the vasa nervorum. Adie's tonic pupil is often idiopathic, but it may develop following viral infection. Conclusions: Ocular complications that involve pupil abnormalities may manifest following COVID-19. In the cases of Adie's tonic pupil, infectious diseases, including COVID-19, should be questioned. Abbreviations: RT PCR = reverse transcription polymerase chain reaction.

Anisocoria Following Uncomplicated Cataract Surgery.

INTRODUCTION: In this report, we describe a case of anisocoria following uncomplicated cataract surgery. Clinicians should consider postoperative mechanical and tonic pupils when evaluating patients with anisocoria. CASE PRESENTATION: A 69-year-old White female underwent uncomplicated cataract surgery of her left eye. No intraoperative pupil expansion devices were used, and no floppy iris or iris prolapse occurred during the surgery. Postoperatively, she was found to have anisocoria. Pharmacologic pupillary testing confirmed a tonic and mechanical left pupil. DISCUSSION: There have been no reported causes of anisocoria from a tonic pupil after cataract surgery. Based on reports of tonic pupils following other eye surgeries, our case likely occurred from a combination of parasympathetic dysfunction and mechanical trauma. CONCLUSIONS: To our knowledge, this is the first report of a tonic pupil following cataract surgery, thus expanding the literature of causes of anisocoria that may be underrecognized in the clinical setting.

A novel case of Horner syndrome as the presenting sign of craniosynostosis.

Craniosynostosis, the premature fusion of cranial sutures, can lead to distortion of skull shape and neurological dysfunction. We present a novel case of Horner syndrome as the presenting sign of craniosynostosis associated with elevated intracranial pressure. A 10-year-old boy presenting for strabismus follow-up was noted to have new-onset anisocoria, greater in the dark, and mild right upper eyelid ptosis. Apraclonidine testing was concerning for Horner syndrome. Neuroimaging demonstrated previously undiagnosed sagittal craniosynostosis with tortuous optic nerves and large cerebrospinal fluid spaces around both optic nerves. The patient was referred to neurosurgery and underwent a lumbar puncture with an opening pressure of 44 cm H2O. He underwent surgical cranial expansion. By six months postoperatively, his anisocoria had resolved.

Describing Anisocoria in Neurocritically Ill Patients.

BACKGROUND: Anisocoria (unequal pupil size) has been defined using cut points ranging from greater than 0.3 mm to greater than 2.0 mm for absolute difference in pupil size. This study explored different pupil diameter cut points for assessing anisocoria as measured by quantitative pupillometry before and after light stimulus. METHODS: An exploratory descriptive study of international registry data was performed. The first observations in patients with paired left and right quantitative pupillometry measurements were included. Measurements of pupil size before and after stimulus with a fixed light source were used to calculate anisocoria. RESULTS: The sample included 5769 patients (mean [SD] age, 57.5 [17.6] years; female sex, 2558 patients [51.5%]; White race, 3669 patients [75.5%]). Anisocoria defined as pupil size difference of greater than 0.5 mm was present in 1624 patients (28.2%) before light stimulus; 645 of these patients (39.7%) also had anisocoria after light stimulus (P < .001). Anisocoria defined as pupil size difference of greater than 2.0 mm was present in 79 patients (1.4%) before light stimulus; 42 of these patients (53.2%) also had anisocoria after light stimulus (P < .001). DISCUSSION: The finding of anisocoria significantly differed before and after light stimulus and according to the cut point used. At most cut points, fewer than half of the patients who had anisocoria before light stimulus also had anisocoria after light stimulus. CONCLUSION: The profound difference in the number of patients adjudicated as having anisocoria using different cut points reinforces the need to develop a universal definition for anisocoria.

Static anisocoria in cats and dogs with naturally occurring tick paralysis (Ixodes holocyclus).

OBJECTIVE: To characterise the novel occurrence and neuro-ophthalmological features of static anisocoria in cats and dogs with tick paralysis (TP) (Ixodes holocyclus) due to a single tick located remote from the head and neck. DESIGN: Observational case series with retrospective analysis. METHODS: Medical records were reviewed from 69 cats and 169 dogs treated for TP from a suburban veterinary hospital in Newcastle, New South Whales, between September 2005 and October 2021. RESULTS: Anisocoria was observed in 2/18 (11.1%) cats and 3/30 (10.0%) dogs with a single tick located remote from the head and neck. These proportions were not different when compared within species to 4 of 28 (14.3%) cats and 16 of 98 (16.3%) dogs with aniscocoria with a single tick located on the head and neck region (P = 1 and 0.56 respectively). Anisocoria arose from pupillary efferent dysfunction and included unilateral oculoparasympathetic dysfunction (internal ophthalmoplegia) in one dog, unilateral oculosympathetic dysfunction (Horner's syndrome) in one cat and one dog, and a combination of bilateral, but asymmetric, oculosympathetic and oculoparasympathetic dysfunction in one cat and one dog. CONCLUSION: It is proposed that anisocoria in cases of TP with a tick located remote from the head and neck is due to an intrinsic latent asymmetry in the safety factor for pupillary efferent function that is unmasked by a systemically distributed holocyclotoxin inhibiting neural transmission within this system, and this is the prevailing pathomechanism, rather than a direct local effect, underscoring anisocoria with a tick located on the head or neck.

Anisocoria without extraocular muscle impairment due to moderate traumatic brain injury with midbrain contusion: a case report.

BACKGROUND: New-onset anisocoria is an important clinical clue to life-threatening intracranial injury. Anisocoria alone without impairment of extraocular muscles is a rare presentation of moderate traumatic brain injury (TBI). CASE PRESENTATION: A 79-year-old woman was transported to hospital soon after falling off a bicycle. Glasgow Coma Scale score on arrival was 11 (E3V3M5). On examination at admission, she was found to be drowsy. Bruising was seen around the right eye and pupil diameters differed (right, 4.5 mm; left, 3.0 mm; both reactive to light). Computed tomography of the head revealed hemorrhagic contusion in the left temporal lobe and left pretectal area of the midbrain, right clavicular fracture, and pulmonary contusion with fractures of the 3rd and 4th ribs. Magnetic resonance imaging confirmed hemorrhagic contusion of the midbrain. The patient achieved full recovery of motor and mental functions with conservative treatment and was discharged on hospital day 17. CONCLUSION: We encountered a case of anisocoria without major extraocular muscle impairment due to moderate TBI with midbrain contusion.

A Rare Case Report of Eight Syndrome Secondary to Syringomyelia Associated with Type I Chiari Malformation.

Eight syndrome is defined as the combination of a unilateral conjugate gaze palsy and ipsilateral seventh cranial nerve palsy. It may occur as a result of demyelinating, vascular, infectious, or compressive lesions of the brainstem localized to the caudal pontine tegmentum. A 43-year-old woman was admitted to our clinic with complaints of headache, inability to look to the left, and weakness on the left side of her face. The complaints had begun abruptly about a month before her admission. Suboccipital decompression surgery for type I Chiari malformation had been performed 10 years earlier. Neuro-ophthalmological examination revealed left-sided horizontal gaze palsy and anisocoria. Cranial and cervical magnetic resonance images revealed cerebellar tonsillar herniation and syringomyelia, the latter of which was considered to be the cause of eight syndrome. No interventions were performed, and periodic follow-up was advised on neurosurgical consultation. Left gaze palsy and facial palsy recovered almost completely in three months, while the anisocoria persisted. Syringomyelia should be considered among the causes of horizontal gaze palsy plus ipsilateral seventh nerve palsy, termed as eight syndrome. Clinical suspicion and appropriate radiological examination can aid in the diagnosis.

Hemiplegia resulting from acute carbon monoxide poisoning.

Carbon monoxide (CO) poisoning can cause neurological complications such as movement disorders and cognitive impairment through hypoxic brain damage. Although peripheral neuropathy of the lower extremities is a known complication of CO poisoning, hemiplegia is very rare. In our case, a patient who developed left hemiplegia due to acute CO poisoning received early hyperbaric oxygen treatment (HBOT). The patient had left hemiplegia and anisocoria at the beginning of HBOT. Her Glasgow coma score was 8. A total of five sessions of HBOT at 243.2 kPa for 120 minutes were provided. At the end of the 5th session, the patient's hemiplegia and anisocoria were completely resolved. Her Glasgow coma score was 15. After nine months of follow-up, she continues to live independently with no sequelae, including delayed neurological sequelae. Clinicians should be aware that CO poisoning can (rarely) present with hemiplegia.

Approach to anisocoria in the emergency department.

Anisocoria describes asymmetric pupillary diameter, which can result from traumatic, pharmacologic, inflammatory, or ischemic effects on the eye. In many cases, anisocoria represents a normal physiologic variant. Morbidity associated with anisocoria is directly related to the inciting cause and can vary from benign to life-threatening. A thorough understanding by emergency physicians of normal ocular neuroanatomy, and of common causes of pathologic anisocoria, including medication-induced anisocoria, can facilitate appropriate resource utilization and timely subspecialty consultation, and can help prevent irreversible ocular injury and patient morbidity. We describe a patient who presented to the emergency department with acute onset of blurry vision with anisocoria.

Brimonidine eye drops reveal diminished sympathetic pupillary tone in comatose patients with brain injury.

BACKGROUND: There is an urgent need for easy-to-perform bedside measures to detect residual consciousness in clinically unresponsive patients with acute brain injury. Interestingly, the sympathetic control of pupil size is thought to be lost in states of unconsciousness. We therefore hypothesized that administration of brimonidine (an alpha-2-adrenergic agonist) eye drops into one eye should produce a pharmacologic Horner's syndrome if the clinically unresponsive patient is conscious, but not if the patient is unconscious. Here, in a first step to explore this hypothesis, we investigated the potential of brimonidine eye drops to distinguish preserved sympathetic pupillary function in awake volunteers from impairment of sympathetic tone in patients in a coma. METHODS: We enrolled comatose patients admitted for acute brain injury to one of the intensive care units (ICU) of a tertiary referral center, in whom EEG and/or neuroimaging for all practical purposes had ruled out residual consciousness. Exclusion criteria were deep sedation, medications with known drug interactions with brimonidine, and a history of eye disease. Age- and sex-matched healthy and awake volunteers served as controls. We measured pupils of both eyes, under scotopic conditions, at baseline and five times 5-120 min after administering brimonidine into the right eye, using automated pupillometry. Primary outcomes were miosis and anisocoria at the individual and group levels. RESULTS: We included 15 comatose ICU patients (seven women, mean age 59 ± 13.8 years) and 15 controls (seven women, mean age 55 ± 16.3 years). At 30 min, miosis and anisocoria were seen in all 15 controls (mean difference between the brimonidine-treated pupil and the control pupil: - 1.31 mm, 95% CI [- 1.51; - 1.11], p < 0.001), but in none (p < 0.001) of the 15 ICU patients (mean difference: 0.09 mm, 95% CI [- 0.12;0.30], p > 0.99). This effect was unchanged after 120 min and remained robust in sensitivity analyses correcting for baseline pupil size, age, and room illuminance. CONCLUSION: In this proof-of-principle study, brimonidine eye drops produced anisocoria in awake volunteers but not in comatose patients with brain injury. This suggests that automated pupillometry after administration of brimonidine can distinguish between the extremes of the spectrum of consciousness (i.e., fully conscious vs. deeply comatose). A larger study testing the "intermediate zone" of disorders of consciousness in the ICU seems warranted.

[Painful anisocoria in a five-year-old child: A rare diagnosis which must not be missed]. / Anisocorie douloureuse chez un enfant de cinq ans : un diagnostic rare à ne pas méconnaître.

Congenital ectropion uveae (CEU) is a rare anomaly of the embryonic development of the anterior segment of the eye. We report the case of a 5-year-old child with an undiagnosed CEU who was treated urgently for an acute angle closure attack. CASE DESCRIPTION: A 5-year-old child was referred urgently for evaluation of anisocoria with mydriasis of the right eye and severe headache. Brain imaging with contrast injection was initially performed in the pediatric emergency department and ruled out central nervous system pathology. The initial examination of the right eye revealed an intraocular pressure (IOP) of 37mmHg, corneal edema, congenital ectropion uveae, mydriasis with pupillary block, a closed angle on gonioscopy, and a clear lens. The examination of the left eye was unremarkable, with no visible CEU. The initial management consisted of medical treatment with topical glaucoma drops and miotics and acetazolamide at 10mg/kg/d. Re-evaluation under general anesthesia showed persistent mydriasis and no resolution of the pupillary block. Filtering surgery was performed in the absence of a complete response to medical treatment, allowing control of IOP without drops and complete regression of the corneal edema. DISCUSSION: CEU is a rare malformation, and pressure complications represent an insignificant proportion of pediatric glaucoma cases. The acute presentation of acute angle closure in this potentially blinding short-term setting, however, makes detection and management difficult in very young children in a great deal of pain. Only one similar case has been reported in the pediatric literature. CONCLUSION: Acute angle closure complicating CEU is exceptional and difficult to diagnose in a pediatric context. Parents of children with this predisposing condition should be informed of the need to consult urgently when clinical signs of elevated intraocular pressure appear.

Sudden anisocoria in a healing pediatric multitrauma patient.

ABSTRACT: This article describes a teenager who developed anisocoria with no obvious neurologic deficits or decline after a motor vehicle accident. The condition resolved over several hours before reappearing in the opposite eye 2 days later. Again no clinical neurologic deficits were noted and the condition resolved after several hours. The patient's asymptomatic anisocoria was finally determined to be secondary to aerosolized ipratropium treatments and an ill-fitting mask.

Mydriasis and anisocoria in a pediatric hyperhidrosis patient with interesting findings in the family cat.

Here, we report a case of unilateral ocular mydriasis in a pediatric patient with longstanding hyperhidrosis, as well as similar findings in her cat. The patient had been undergoing treatment of her hyperhidrosis with topical glycopyrrolate. This case highlights the potential side effect profile of topical antimuscarinics and the importance of counseling patients on proper precautions.

Anisocoria and mydriasis after scalp nerve block: a case report.

Strategies for the assessment of abnormal neurological findings during general anesthesia are limited. However, pupil abnormalities may represent serious neurological complications. We herein present a case of new-onset anisocoria and mydriasis that developed after scalp nerve block. The patient's signs were possibly related to increased intracranial pressure with resulting brain shift that ultimately affected the oculomotor nerves. A 45-year-old man was scheduled for left cerebellar tumor resection and ventricular drainage surgery; however, anisocoria and left pupillary mydriasis were observed after induction of general anesthesia and performance of scalp nerve block. After reducing the intracranial pressure, the right pupil showed constriction (1 mm) but the left pupil was dilated (5 mm). The pupils were of similar size postoperatively. Although pupillary dilation during general anesthesia has been previously described, this is the first case in which the mydriasis was considered to have been caused by brain shift due to increased intracranial pressure after scalp nerve block. Thus, we propose this phenomenon as a new possible cause of pupillary changes. Actively monitoring this presentation intraoperatively could enable early detection of and intervention for complications, therefore improving the prognosis.