New-onset Diplopia May Be Early Warning Sign of GCA

Study suggests that diplopia in GCA patients is more frequently reported due to abducens nerve palsy than oculomotor or trochlear nerve palsies. These findings underscore the clinical value of new-onset binocular diplopia as an early warning sign of GCA, warranting prompt investigation and treatment to mitigate risk of further vision loss. Photo: Cecelia Koetting, OD, and Richard Mangan, OD. Click image to enlarge. Diplopia is an infrequent manifestation of giant cell arteritis (GCA) but may precede other visual disturbances such as transient or permanent vision loss. In a recent study, researchers estimated the literature-pooled prevalence of diplopia in GCA patients stratified by cranial nerve (CN) involvement. The findings suggest that diplopia is more frequently reported in abducens nerve palsy compared to oculomotor and trochlear nerve palsies. This data was reported in Eye.This systematic review and meta-analysis of 50 studies, encompassing 21,680 patients and 664 diplopia events, determined that the pooled prevalence of binocular diplopia in GCA patients is 7.15%. This estimate is consistent with previously assumed ranges of 1% to 19%, highlighting the clinical value of diplopia as an early warning sign of GCA and its related complications. “In several reported cases, diplopia preceded other more catastrophic ocular complications, such as permanent visual loss,” the authors wrote in their paper. “Accordingly, diagnosing GCA and initiating earlier treatment can mitigate potential risk of visual loss.”Several different mechanisms may lead to diplopia in GCA. The most common attribution is ischemia of cranial nerves III (oculomotor), IV (trochlear) and VI (abducens). The authors identified palsies of CN III, IV and VI in 0.96%, 0.30% and 1.41% of GCA patients with diplopia, respectively, potentially suggesting that the abducens nerve may be particularly vulnerable to ischemia in GCA. According to the authors, this is consistent with prior literature.“The abducens nerve has a long subarachnoid course, relies on small penetrating arteries and traverses confined anatomical spaces, such as Dorello’s canal, so vasculitis of adjacent vessels in GCA may lead to ischemic injury,” they explained in their paper. “However, most studies included in this review did not report the presence or absence of cranial nerve involvement, so this finding should be considered cautiously.”Another proposed mechanism is brainstem ischemia due to vertebrobasilar vasculitis, the authors noted. GCA can involve the vertebral and basilar arteries, leading to ischemia of the brainstem regions that harbor cranial nerve nuclei.In cases of GCA presenting with diplopia, acute management remains immediate initiation of high-dose glucocorticoids to lower the risk of permanent vision loss, regardless of which CN is involved. “Nerve identification may help inform prognosis, since different cranial nerves may recover at slightly varying rates (CN VI palsies in GCA typically resolve within three to four weeks after starting treatment, whereas CN III palsies may improve more rapidly within 10 to 21 days),” the authors explained in their paper. They noted that these differences may offer eye doctors, neurologists and rheumatologists “insights into discharge planning and patient education regarding prognosis and follow-up.”In conclusion, these findings underscore the clinical value of new-onset binocular diplopia as an early warning sign of GCA, warranting prompt investigation and treatment to mitigate risk of further vision loss.Click here for the journal source. Dhivagaran T, Butt FR, Nasri D, et al. Prevalence of diplopia among giant cell arteritis patients: a systematic review and meta-analysis. Eye. January 15, 2026. [Epub ahead of print]. This article was developed by the editorial staff in conjunction with experts in the field. In the process, AI may have been among the editorial tools used to meet the goals of human editors, who approved all content.