Title:Internuclear Ophthalmoplegia as an Isolated Symptom of Brainstem
Wake-up Stroke Responsive to Intravenous Thrombolysis: Evidence from
MRI
Volume: 19
Author(s): Gaetano Barbagallo*, Marcella Caggiula, Annalisa Rizzo, Vita Direnzo, Angela Lupo, Antonio Fasano, Cosimo Angelo Greco, Alfredo Pauciulo, Antonio Saponaro, Adriana Paladini and Leonardo Barbarini
Affiliation:
- Division of Neurology, Vito Fazzi Hospital, Lecce, Italy
Keywords:
Internuclear Ophthalmoplegia (INO), brainstem wake-up stroke, magnetic resonance imaging (MRI), diffusion weighted imaging/fluid attenuated inversion recovery (DWI/FLAIR) mismatch, intravenous thrombolysis (IVT).
Abstract:
Background: Internuclear ophthalmoplegia (INO) is a disorder of eye movements caused
by a lesion involving the medial longitudinal fasciculus (MLF) within the brainstem, and it is characterized
by adduction impairment combined with contralateral dissociated abduction nystagmus. The
frequency of acute ischemic stroke (AIS) presenting with INO as a predominant symptom is very low,
and many patients suffering from this brainstem AIS are precluded from intravenous thrombolysis
(IVT).
Objective: To provide for the first time a magnetic resonance imaging (MRI) evidence of response to
the IVT in brainstem wake-up stroke presenting with INO as an isolated symptom.
Methods: Here, we described a rare case of pons AIS presenting with INO as a unique symptom of
awakening. In order to differentiate an ischemic stroke from other stroke mimics, and to determine
whether the patient was within the therapeutic window for IVT (wake-up stroke), brain MRI including
DWI and FLAIR sequences was acquired.
Results: A left paramedian pontine DWI/FLAIR mismatch was detected and the patient was considered
eligible for IVT. After IVT, the patient made a full recovery with complete resolution of INO.
Follow-up MRI at 1 month demonstrates the absence of ischemic lesions.
Conclusion: Our case provides neuroradiological evidence of IVT efficacy in brainstem stroke, and it
should prompt clinicians to rapidly perform MRI in wake-up onset INO and to just as quickly administer
IVT, since INO is a functionally disabling deficit. Finally, this case demonstrates the value of MRI
in diagnostic, prognostic, and therapeutic workup of posterior circulation wake-up stroke.