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Choosing an intraocular lens for patients with large pupils.

Optical aberration from the positioning holes of a posterior chamber intraocular lens was encountered in three patients with wide spontaneous dilation of the pupil in scotopic conditions. One patient had a cataract extraction in his fellow eye with implantation of a posterior chamber lens without positioning holes in its optical portion and has not encountered any aberrations in that eye. We suggest that in such patients, careful preoperative measurement of the pupillary size in a dark room should be done and lenses without positioning holes on the optic should be used to prevent optical aberrations.

Darkness↗

Phasic pupil dilation response to noxious stimulation in normal volunteers: relationship to brain evoked potentials and pain report.

Pupillary response to noxious stimulation was investigated in men (n = 11) and women (n = 9). Subjects experienced repeated trials of noxious electrical fingertip stimulation at four intensities, ranging from faint to barely tolerable pain. Measures included pupil dilation response (PDR), pain report (PR), and brain evoked potentials (EPs). The PDR began at 0.33 s and peaked at 1.25 s after the stimulus. Multivariate mixed-effects analyses revealed that (a) the PDR increased significantly in peak amplitude as stimulus intensity increased, (b) EP peaks at 150 and 250 ms differed significantly in both amplitude and latency across stimulus intensity, and (c) PR increased significantly with increasing stimulus intensity. Men demonstrated a significantly greater EP peak amplitude and peak latency at 150 ms than did women. With sex and stimulus intensity effects partialled out, the EP peak latency at 150 ms significantly predicted PR, and EP peak amplitude at 150 ms significantly predicted the PDR peak amplitude.

Adolescent↗

Brain activation and pupil response during covert performance of the Stroop Color Word task.

Patterns of brain activation associated with covert performance of the Stroop Color-Word task were studied in young, healthy, adult volunteers using blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI). Comparisons of the incongruous Stroop condition were made with both color naming and word reading baselines. Areas of the left and right anterior cingulate, the right precuneus, and the left pars opercularis displayed larger BOLD signal responses during the incongruous Stroop condition than during baseline conditions. Activation of BOLD signals in these areas was highly repeatable. In a second experiment, pupil diameter was used to assess cognitive load in 7 individuals studied during overt and covert performance of both Stroop and color naming conditions. Cognitive load was similar in overt and covert response conditions. Results from the BOLD study indicate that brain regions participating in selective visual attention and in the selection of motor programs involved in speech were activated more by the Stroop task than by the baseline tasks. The neural substrate involved in the resolution of the perceptual and motor conflicts elicited by the Stroop Color-Word task does not appear to be a single brain region. Rather, a network of brain regions is implicated, with separate regions within this system supporting distinct functions.

Adult↗

The influence of drop size on pupil dilatation.

The clinical efficacy of reduced size dilating drops (micro drops), was assessed in 60 patients. For each patient, one eye received the standard 'minim' drop size (26 microliters) while the fellow eye received a micro drop of five microliters. In 20 patients tropicamide 1% was followed after two minutes by phenylephrine 10%, another 20 patients were given tropicamide 1% alone, and for the last 20 patients, 0.5% tropicamide was used. Satisfactory mydriasis was achieved for all pupils except those receiving micro drops of tropicamide 0.5% (25 micrograms tropicamide). Tropicamide 1% in micro drop formulation (50 micrograms tropicamide) gave almost identical mydriasis to that from standard drops (containing 250 micrograms tropicamide). Tropicamide 1% in combination with phenylephrine 10% was superior to tropicamide 1% alone, after standard or micro drop administration. The micro drops used in this study were effective, easy to administer, and caused less patient discomfort.

Drug Administration Schedule↗

The oval pupil.

The dynamics of pupillary dilation induced by Phenylephrine 10% and Cyclopentolate 1% have been examined by flash photography. A correlation between anterior chamber depth and the pupil shape on dilation with Phenylephrine Hydrochloride 10% is described. It is postulated that these pupillary dilation dynamics support a sympathetic abnormality as a trigger for acute primary angle closure glaucoma.

Adolescent↗

Changes in intraocular pressure and pupil size following intramuscular administration of hydromorphone hydrochloride and acepromazine in clinically normal dogs.

OBJECTIVE: To investigate the effects of intramuscularly administered hydromorphone hydrochloride and acepromazine on intraocular pressure (IOP) and pupil size (PS). ANIMALS STUDIED: Seventeen dogs free of clinically relevant ocular abnormalities. PROCEDURE: Measurements of IOP and PS were obtained and the dogs were injected intramuscularly with hydromorphone (0.04-0.08 mg/kg) and acepromazine (0.04 mg/kg). Measurements of IOP and PS were repeated 10 min and 25 min later. RESULTS: Though a decreasing trend in IOP values was demonstrated, no significant difference was noted in IOP from the initial examination to examination following intramuscular administration of hydromorphone and acepromazine. Significant miosis was present in 16 of 17 dogs at 10 min and 25 min following administration of hydromorphone and acepromazine. CONCLUSION: Hydromorphone (0.04-0.08 mg/kg) and acepromazine (0.04 mg/kg) cause significant miosis in dogs at 10 and 25 min following intramuscular administration.

Acepromazine↗

[Blocking mechanisms of the pupil and posterior surface of the iris].

After covered fistulizing operations for primary glaucoma without complications the anterior chamber is deeper than it was prior to surgery. This means that the contact between the posterior surface of the iris and the lens may be very important in the pathogenesis of all primiary glaucomas, especially in acute primary glaucoma: an acute iridolenticular block can develop. Severe blocking mechanisms of the posterior surface of the iris sometimes appear after fistulizing glaucoma operations and after cataract extractions (with and without implantation of a pseudophakos) if there is no postoperative dilatation of th pupil. Peripheral iridectomies alone cannot prevent the anterior chamber from becoming shallower or flattened, possibly with the development of malignant glaucoma.

Glaucoma↗

Cocaine abuse, generalized myasthenia, complete external ophthalmoplegia, and pseudotonic pupil.

We present the case of a 29-year-old woman with generalized myasthenia. Myasthenia with complete external ophthalmoplegia was unmasked by cocaine abuse. It was associated with changes of the pupillary motility, including light-near dissociation and positive 0.1% pilocarpine test. Treatment with acetylcholinesterase inhibitors improved the patient's condition rapidly, and led to complete normalization of extraocular movements and pupillary function. To our knowledge, this is the fourth case of cocaine-related myasthenia, and the first case of myasthenia with pseudotonic pupil.

Adult↗

The effect of intravenous medetomidine on pupil size and intraocular pressure in normotensive dogs.

Medetomidine, a highly specific alpha-2 adrenergic agonist, has been demonstrated to lower intraocular pressure (IOP) in rabbits and cats when applied topically. The purpose of this study was to assess the influence of intravenously injected medetomidine on the pupil size (PS) and the IOP of non glaucomatous dogs. IOP was measured by applanation tonometry and PS was measured using Jameson calipers at t=0 (or time of IV injection of medetomidine (Domitor; Orion) at the dose of 1500 microg/m2 body surface area) and again after 5 minutes (t=5). The IV administration of medetomidine caused miosis in all 14 dogs. The mean PS decreased from 9.0 to 4.0 mm (p<0.001). The IOP was lowered in 10 dogs and in 4 dogs there was a rise in IOP. The mean IOP (mmHg) decreased from 22 to 21 (p>0.2). The data presented above confirm that medetomidine at a dose of 1500 microg/m2 body surface area produces miosis in non glaucomatous dogs, without influencing the IOP.

Adrenergic alpha-Agonists↗

Effects on intraocular pressure and pupil size in glaucomatous beagles after topical pilocarpine instilled with standard (pH 5) and buffer-tip (pH 7) droptainers.

Single doses (50 microliters) of 1% and 2% pilocarpine, instilled by a buffer-tip droptainer resulting in an approximate pH 7.0 solution, and 1, 2, and 4% pilocarpine, instilled by the standard droptainer, resulting a pH 5.0 solution, were evaluated in the glaucomatous Beagle model. Pupil size and intraocular pressure measurements were performed at 0, 1/4, 1/2, 3/4, 1, 2, 4, 6, and 8 hours. Signs of topical irritation (blepharospasm, conjunctival hyperemia and chemosis, and any corneal changes) were also monitored. Both solutions produced similar onset and duration of miosis and ocular hypotension, but the pH 5.0 solutions produced a brief elevation in intraocular pressure during the first hour post-drug instillation. Moderate blepharospasm, conjunctival hyperemia, and chemosis occurred with only the pilocarpine solutions with pH 5.0.

Administration, Topical↗

Effect of different dose schedules of 0.15% unoprostone isopropyl on intraocular pressure and pupil size in the glaucomatous beagle.

The changes in intraocular pressure (IOP) and pupil size (PS) after instillations of 0.15% unoprostone isopropyl (Rescula, Novartis Ophthalmics, Duluth, GA) were investigated in the spontaneous glaucoma Beagle model. From the first-day baseline IOP of 27.3+/-3.2 mmHg placebo eye and 32.8+/-5.1 mmHg control eye, the mean+/-standard error of the mean (SEM) diurnal changes after 0.15% unoprostone, at 8 AM once-daily for the next 4 days, were 15.5+/-1.3 mmHg, 14.7+/-1.9 mmHg, 16.1+/-1.1 mmHg, and 17.0+/-1.5 mmHg, respectively, and were significantly different from the control eye. After 0.15% unoprostone was instilled at 8 PM, the mean+/-SEM baseline changes from the baseline IOP (insert drug eye 9 AM) in the drug eyes were 5.9+/-2.5 mmHg, 5.2+/-4.1 mmHg, 9.7+/-2.5 mmHg, and 3.6+/-3.6 mmHg, respectively. When 0.15% unoprostone was instilled twice-daily, the mean+/-SEM baseline IOP (insert drug eye 9 AM) changes were 13.6+/-0.7 mmHg, 13.9+/-1.4 mmHg, 11.3+/-1.0 mmHg, and 9.3+/-1.4 mmHg, respectively, and were significantly different from the control eyes. Miosis occurred within 2 hours and lasted several hours. Unoprostone isopropyl instilled once-daily (AM or PM), as well as twice-daily, produces significant decreases in IOP and PS in the glaucomatous Beagle.

Animals↗

Emergent decompressive craniectomy in patients with fixed dilated pupils due to cerebral venous and dural sinus thrombosis: report of three cases.

OBJECTIVE AND IMPORTANCE: Cerebral venous and dural sinus thrombosis is a rare cause of stroke. Although morbidity and mortality have greatly decreased in recent years as a result of early diagnosis and timely medical treatment, when coma occurs the prognosis remains poor. We evaluated whether emergent decompressive craniectomy has a role in the treatment of patients with brain herniation from dural sinus thrombosis and hemorrhagic infarct. CLINICAL PRESENTATION: Three patients developed large hemorrhagic infarct with coma and bilaterally fixed and dilated pupils resulting from aseptic dural sinus thrombosis. INTERVENTION: Two patients underwent emergent surgical decompression as soon as brain herniation developed, and these patients had complete functional recovery. One underwent delayed surgical decompression and remained severely disabled. CONCLUSION: Our results provide preliminary evidence that emergent decompressive craniectomy is effective in patients with brain herniation from dural sinus thrombosis, provided that the clinical onset is recent. We therefore recommend consideration of this aggressive surgical technique for such patients, who may survive with good outcomes.

Adult↗

Marcus Gunn pupil in a possible case of unilateral retinitis pigmentosa.

A possible case of unilateral retinitis pigmentosa (RP) is reviewed. The electrodiagnostic and clinical findings are discussed, with perspective given to alternative diagnoses. A review of the literature is included to show the controversy which clouds a positive diagnosis of unilateral RP. A co-existing Marcus Gunn pupil is defined and discussed in relation to unilateral RP-like processes.

Diagnosis, Differential↗

Pupil dependency of bifocal contact lenses.

The advantages and the problems associated with use of alternating vision and simultaneous vision bifocal contact lenses are analyzed. The changes in pupil diameter associated with changes in illumination and in the distance of the task make the selection of the best bifocal design complex.

Adult↗

Relative pupil-sparing oculomotor nerve palsy as the presenting sign of posterior fossa meningioma.

We report a case of relative pupil-sparing oculomotor paresis initially attributed to ischemia because weakness of other cranial nerves was minimal and dismissed as insignificant. Neuroimaging eventually revealed a posterior fossa meningioma. The neurologic symptoms and signs disappeared immediately after resection of the tumor. The third nerve palsy was attributed to deformation of the brainstem. This case reinforces the importance of neuroimaging even in patients who have apparently isolated oculomotor palsy with features not classic for an ischemic etiology.

Aged↗

Segmental facial anhidrosis and tonic pupils with preserved deep tendon reflexes: a novel autonomic neuropathy.

A 31-year-old woman had exertional right-sided hemifacial flushing and sweating. Examination demonstrated slightly dilated pupils with absent constriction to light and a tonic near response and redilatation, features consistent with Adie syndrome. Neurological examination was otherwise normal, including preservation of deep tendon reflexes. Magnetic resonance imaging of brain and spine were normal. The combination of unilateral loss of sudomotor and vasomotor activity without loss of ocular sympathetic innervation fulfills the diagnosis of Harlequin syndrome. The combination of Harlequin and Adie syndromes has been called Ross syndrome, but the preservation of deep tendon reflexes precludes a diagnosis of Ross syndrome in our patient. This previously undescribed variant adds further complexity to the spectrum of autonomic neuropathies.

Adie Syndrome↗