Skew deviation as a complication of cardiac catheterization

The Clinical and Imaging Profile of Skew Deviation: A Study of 157 Cases

BACKGROUND

Skew deviation, a vertical misalignment of the eyes caused by a lesion in the vestibulo-ocular pathway, is a common manifestation of brainstem dysfunction, yet comprehensive information about its clinical profile is lacking. The aim of this study was to document presenting symptoms, causes, ocular alignment features, accompanying neurologic signs, pertinent brain imaging abnormalities, and measures used to relieve diplopia.

METHODS

We searched the electronic medical records text from 2000 to 2018 for "skew" or "skew deviation" at a tertiary care academic center, including only patients diagnosed under supervision of faculty neuro-ophthalmologists. After excluding patients with features suggesting an imitator of skew deviation, we collected data useful in answering the selected clinical issues.

RESULTS

In a cohort of 157 patients, vertical misalignment ranged between 1 and 30 prism diopters (PD) (median 5 PD) and was comitant in 100 (64%) patients. Diplopia was reported by 87% and blurred vision by 11% of patients. Blurred vision was more common when vertical misalignment was less than 3 PD. At least one accompanying neurologic sign was present in 133 (85%) patients, most often nystagmus, followed by gaze paresis, ataxia, saccadic pursuit, and internuclear ophthalmoplegia. Stroke affecting the thalamus, brainstem, or cerebellum accounted for 82 (52%) of cases. Stroke was usually ischemic, mostly unprovoked, but also occurring after intracranial or extracranial surgical procedures. Brainstem tumor and operative injury caused most of the remaining cases. A subgroup of 17 (11%) patients had skew deviation as the only new clinical sign and had no pertinent brain imaging abnormalities. Resolution of skew deviation, documented in 58 (42%) of 137 patients who had at least one follow-up visit, usually occurred within 3 months, but sometimes not until after 12 months. Of 110 patients who still had diplopia on follow-up examinations, the diplopia was successfully relieved with prism spectacles in 68 (62%). The cause of the skew deviation, amount of vertical misalignment, and degree of incomitance did not predict the success in relieving diplopia. Accompanying neurologic signs, including ataxia, endured in 44% of patients and were often more debilitating than the diplopia of skew deviation.

CONCLUSIONS

The amplitude of misalignment in skew deviation varies widely but is generally 5 PD or less. When misalignment is 3 PD or less, patients report blurred vision rather than diplopia. Skew deviation is usually accompanied by other neurologic signs reflecting brainstem dysfunction. Yet there is a small subgroup in which vertical misalignment is an isolated sign, and there are no supporting brain imaging abnormalities. The main cause of skew deviation is ischemic stroke, which affects not only the brainstem but also the thalamus. Diplopia from skew deviation frequently persists, in which case prism spectacles may be successful in palliating it. Accompanying neurologic signs, especially ataxia, may outlast skew deviation and be more debilitating.

Differentiating Acute and Subacute Vertical Strabismus Using Different Head Positions During the Upright-Supine Test

Importance

Accurate clinical differentiation between skew deviation and fourth nerve palsy (4NP) is critical in the acute and subacute settings.

Objective

To determine the sensitivity and specificity of the upright-supine test to detect vertical misalignment changes using different head positions for the diagnosis of acute or subacute skew deviation vs 4NP.

Design, Setting, and Participants

This multicenter study enrolled consecutive patients from Coimbra University Hospital Centre, Coimbra, Portugal, and Michigan State University, Lansing, within 2 months of presenting with vertical diplopia and diagnosed as having skew deviation or acquired unilateral 4NP. The study used nonmasked screening and diagnostic test results from June 1, 2013, to December 31, 2016. Data were analyzed from January 1, 2017, to June 30, 2017.

Main Outcomes and Measures

A 50% or greater change in vertical misalignment between the upright and supine positions, with the head centered and tilted to either side. Measurements included the alternate prism and cover (APC) test, the double Maddox rod test, the APC test change index ([measurement upright - measurement supine] / [measurement upright + measurement supine]), and the APC test sensitivity and specificity.

Results

Of the 37 included patients, the mean (SD) age was 58 (14) years, and 26 (70%) were male. We enrolled 19 patients (51%) with skew deviation and 18 (49%) with 4NP. Eighteen patients with skew deviation (95%) showed additional ocular motor and/or neurological signs. When moving to the supine position, only 1 patient with skew deviation (5%) showed more than a 50% decrease of hypertropia with the head centered (APC test: sensitivity, 5%; specificity, 100%). Three patients with 4NP (17%) showed more than a 50% decrease of hypertropia with the head tilted toward the hypertropic eye, and 10 patients with 4NP (56%) showed more than a 50% increase of hypertropia with the head tilted toward the hypotropic eye. Change indexes were different between the skew deviation and 4NP groups for head tilt to the hypotropic eye (difference, -0.33 prism diopters; 95% CI, -0.43 to -0.20; P < .001). Cyclotorsion worsened in the supine position only in patients with skew deviation (hypertropic eye: difference, -7.6 prism diopters; 95% CI, -13.00 to -0.75; P = .01; hypotropic eye: difference, 8.2 prism diopters; 95% CI, 0 to 15.75; P = .03).

Conclusions and Relevance

The upright-supine test with the head centered is not a sensitive method to separate acute or subacute skew deviation from 4NP. Conversion of an incomitant vertical deviation in the upright position to a comitant vertical strabismus in the supine position in all head positions, as well as the absence of additional ocular motor and/or neurologic signs, may constitute a more useful clue.

Simultaneous multiple branch retinal artery occlusions after diagnostic cardiac catheterization

PURPOSE

We describe a 53-year-old man with a decrease in visual acuity in the left eye 2 weeks after diagnostic cardiac catheterization.

DESIGN

Interventional case report.

METHODS

A 53-year-old man with a decrease in visual acuity in the left eye 2 weeks after diagnostic cardiac catheterization underwent ophthalmoscopic, angiographic, and laboratory evaluations. Both funduscopy and fluorescein angiography confirmed the diagnosis of simultaneous multiple branch retinal artery occlusions in the left eye.

RESULTS

The left eye had a mildly positive (1+) relative afferent pupillary defect. Slit-lamp biomicroscopy was unremarkable except for 2+ nuclear cataract bilaterally. Intraocular pressure was 12 mmHg in the right eye and 11 mmHg in the left eye by applanation tonometry. Funduscopy revealed a normal right eye.

CONCLUSION

This case report of multiple branch retinal artery occlusions due to cholesterol embolus after diagnostic cardiac catheterization is extremely rare. Visual symptoms after cardiac catheterization should alert both ophthalmologists and cardiologists to this potential post-cardiac catheterization complication.

Skew Deviation Revisited

Skew deviation is a vertical misalignment of the eyes caused by damage to prenuclear vestibular input to ocular motor nuclei. The resultant vertical ocular deviation is relatively comitant in nature, and is usually seen in the context of brainstem or cerebellar injury from stroke, multiple sclerosis, or trauma. Skew deviation is usually accompanied by binocular torsion, torticollis, and a tilt in the subjective visual vertical. This constellation of findings has been termed the ocular tilt reaction. In the past two decades, a clinical localizing value for skew deviation has been assigned, and a cogent vestibular mechanism for comitant and incomitant variants of skew deviation has been proposed. Our understanding of skew deviation as a manifestation of central otolithic dysfunction in different planes of three-dimensional space is evolving. The similar spectrum of vertical ocular deviations arising in patients with congenital strabismus may further expand the nosology of skew deviation to include vergence abnormalities caused by the effects of early binocular visual imbalance on the developing visual system.