Eating-induced blepharospasm after cataract surgery in a patient with a previous stroke

Dear Sir, A 36-year-old man with a medical history of bilateral thalamic stroke 6 years ago presented to our institute due to blepharospasms appearing soon after a cataract operation 3 months ago. The blepharospasms were always triggered during eating, and bright light increased the severity of the blepharospasms. Neurological examination revealed normal cranial nerves, except eating-induced blepharospasms [Video 1]. The patient could not initiate voluntary opening of the eyelids, which was compatible with apraxia of eyelid opening. He used his hands to overcome the blepharospams and he preferred to avoid bright lights. Cranial magnetic resonance imaging showed chronic bilateral paramedian thalamic ischemic lesions [Figure 1]. Of note, the blink reflexes were bilaterally normal showing the intact corneal reflex pathway passing through the lower brainstem. Botulinium toxin (30 IU) was administered bilaterally in the periocular region that provided moderate improvement in the clinic. {"href":"Single Video Player","role":"media-player-id","content-type":"play-in-place","position":"float","orientation":"portrait","label":"Video 1","caption":"","object-id":[{"pub-id-type":"doi","id":""},{"pub-id-type":"other","content-type":"media-stream-id","id":"1_oaw05nsr"},{"pub-id-type":"other","content-type":"media-source","id":"Kaltura"}]} Figure 1:: T2-weighted cranial magnetic resonance imaging showing chronic infarction in the bilateral ventromedial thalamus (arrows)In this report, we ilustrate an interesting subtype of blepharospasm, which may provide perspectives regarding the pathophysiology of blepharospasms. Tanaka et al.[1] described a large group of patients with blepharospasms as a post-surgical maladaptation syndrome of cataract surgery. In the largest study including 1,113 patients with blepharospams, 108 patients (9.7%) had developed blepharospasms in the clinic immediately following the surgical procedure, the most common procedure being cataract surgery (80%).[2] The authors explain the occurrence of blepharospasms following cataract surgery via a mechanism of increased vision triggering photophobia, which is frequently reported in patients with blepharospasms.[3] However, eating behavior triggered the blepharosams, and cranial magnetic resonance imaging showed vascular lesions in the bilateral thalamus, which were interesting points in our patient. In addition, the blink reflexes that evalaute the integrity of the trigeminal nerve, facial nerve, and lower brain stem were normal. Photophobia in blepharospasms is considered to be induced by impairments within several thalamic processing circuits.[2,4] Similarly, in the setting of a lesioned thalamus, we hypothesize that the increased visual input after a cataract operation may cause exaberation of the malfunction in sensory processing. Of note, the increased sensory inputs during the eating action may lead to an overload in these abnormal sensory circuits, resulting in the transient exaberation of the blepharospasms. However, future reports with larger patient groups with atypical features may susbtantially contribute to our understanding of the pathophysiology of this manifestation. Acknowledgements None Authors' contributions Concept – Halil Onder, Selcuk Comoglu; Design – Halil Onder; Supervision – Selcuk Comoglu; Materials – Halil Onder, Selcuk Comoglu; Data Collection and/or Processing – Halil Onder; Analysis and/or Interpretation – Halil Onder, Selcuk Comoglu; Literature Search – Halil Onder; Writing Manuscript – Halil Onder, Critical Review– Selcuk Comoglu. Ethical compliance statement This manuscript has been prepared in accordance with the standards of the ethics committee of Etlik City Hospital and Helsinki Declaration. The informed consent form has been obtained from the patient. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.