Abstract 1122‐000051: Isolated Diplacusis Due to Ipsilateral Temporal Lobe Infarction: A Case Report

Introduction : Double hearing or Diplacusis is a synchronous double perception of a sound and can have Binauralis or Monauralis pattern, with inner ear disorders being the main culprit [1] . Other forms of Auditory illusions have been reported as a co‐manifestation of stroke syndromes, but none as an isolated presentation [1][2] . This is a case of a 77‐year‐old male with acute onset isolated Diplacusis in a patient due to a right temporal lobe ischemic infarct. To our knowledge, this is the first case report of an isolated diplacusis due to cortical infarct. Methods : A case presentation with Pubmed search of review articles and case reports. Results : The patient had a past medical history of sensorineural deafness in his left ear. He described any sound heard as the same quality but occurring with an echo heard a fraction of a second later in his right ear. There was no decreased hearing quality or tinnitus reported in his right ear. His drug screen test was negative. His examination was only remarkable for a sensorineural hearing loss pattern on his left ear. His (NIHSS) was zero, and no other cranial nerve abnormalities were detected. His MRI was significant for a punctate restricted diffusion on the right temporal lobe, resembling an ischemic infarct (Figure). Conclusions : Isolated diplacusis can present as acute ischemic stroke in the temporal lobe. Further studies are needed to understand its pathophysiology.

Hypercoagulability as Measured by Thrombelastography May Be Associated with the Size of Acute Ischemic Infarct—A Pilot Study

Background: Thromboelastography (TEG®) measures coagulation function in venous blood. Previous studies have reported that this device providing an integrated data on dynamics of clot formation may be useful for predicting clinical outcome in ischemic stroke. We investigated whether a hypercoagulability detected by thrombelastography may be associated with larger size of acute ischemic infarct. Methods: We included 40 ischemic stroke subjects with large artery atherosclerosis or small-vessel disease to a cross-sectional pilot study. Thrombelastography parameters related to time of clot formation (R- reaction time, K-clot kinetics), clot growth and strengthening (angle-alpha and MA-maximum amplitude) and lysis (Ly30) were performed within first 24 h after the onset of stroke. A volume of ischemic infarct was assessed on the basis of diffusion-weighted imaging (DWI) sequence of magnetic resonance imaging. Results: In the entire group, we reported that subjects with a large ischemic focus (>2 cm3) had a higher diameter of a clot (measured as MA) than subjects with a small ischemic focus (p = 0.0168). In the large artery atherosclerosis subgroup, we showed a significant correlation between MA and size of acute infarct (R = 0.64, p = 0.0138), between angle (alpha) and size of acute infarct (R = 0.55, p = 0.0428) and stroke subjects with hypercoagulability (MA > 69 mm) had significantly higher probability of a larger size of acute ischemic focus compared to normalcoagulable subjects (5.45 cm3 vs. 1.35 cm3; p = 0.0298). In multivariate logistic regression hypercoagulability was a predictor of a large size of ischemic infarct (Odds ratio OR = 59.5; 95% confidence interval (CI) 1.08–3558.8; p = 0.0488). Conclusions: We emphasized that thrombelastography, based on the parameters related to clot strength, may have clinical utility to identify the risk of the extensive ischemic infarct.

Case Report: Thalamomesencephalic stroke in a patient with HIV

We present a 41-year-old HIV-positive female patient complaining of complete right palpebral ptosis, diplopia, and inability to balance herself. On examination, the right eye was able to move laterally and downwards. The motor exam showed left hemiparesis (4/5) on upper and lower limbs, bilateral Babinski sign with left hemiataxia without the sensory disorder. CT scan and magnetic resonance imaging angiography demonstrated an ischemic infarct on the right paramedian branch of the posterior cerebral artery territory. This patient did not present clinical manifestations of the thalamic lesion. To our knowledge, this is the first reported case of a young patient presenting a unilateral thalamomesencephalic ischemic stroke secondary to HIV vasculitis with bilateral Babinski signs and without thalamic signs in the medical literature.

Unfavorable Changes of Platelet Reactivity on Clopidogrel Therapy Assessed by Impedance Aggregometry Affect a Larger Volume of Acute Ischemic Lesions in Stroke

Background: High on-treatment platelet reactivity or its equivalent—resistance to the antiplatelet agent—significantly reduces the efficacy of the therapy, contributing to a negative impact on stroke course. Previous studies demonstrated that aspirin resistance is associated with a larger size of acute ischemic infarct. Due to the increasing use of clopidogrel in the secondary prevention of stroke, we aimed to assess the impact of clopidogrel resistance on the size and extent of ischemic lesions, both acute and chronic. Methods: This prospective, single-center and observational study involved 74 ischemic stroke subjects, treated with 75 mg of clopidogrel. We used impedance aggregometry to determine platelet reactivity 6–12 h after a dose of clopidogrel as a first assessment and 48 h later as the second measurement. A favorable dynamics of platelet reactivity over time was the decrease in the minimum value equal to the median in the entire study. The volume of acute ischemic infarct was estimated within 48 h after onset in diffusion-weighted imaging and fluid-attenuated inversion recovery sequences of magnetic resonance and the severity of chronic vascular lesions by Fazekas scale. Results: Subjects with mild severity of chronic vascular lesions (Fazekas 1) exhibited a significant decrease of platelet reactivity over time (p = 0.035). Dynamics of platelet reactivity over time differed between subjects with large, moderate, mild and insignificant size of acute ischemic lesion (Kruskall-Wallis H = 3.2576; p = 0.048). In multivariate regression models, we reported unfavorable dynamics of platelet reactivity alone and combined with a high initial value of platelet reactivity as independent predictors of higher risk of a significant ischemic infarct volume (OR 7.16 95%CI 1.69–30.31, p = 0.008 and 26.49 95%CI 1.88–372.4, p = 0.015, respectively). Conclusions: We emphasized that unfavorable dynamics of platelet reactivity over time during clopidogrel therapy in acute phase of stroke affect the volume of acute infarct and the severity of chronic vascular lesions.

Infant Stroke Associated With Left Atrial Thrombus and Supraventricular Tachycardia

We report a rare case of cardioembolic stroke in the setting of supraventricular tachycardia (SVT) in an infant. After a week of irritability, a 10-week-old male presented to the emergency department with SVT requiring treatment with adenosine. He developed right-sided hemiparesis and focal motor seizures. Imaging of the brain showed ischemic infarct in the left middle cerebral artery (MCA) territory. Echocardiogram showed a newly formed large left atrial intracardiac thrombus. A coagulopathy workup was negative. He was treated with beta-blocker and anticoagulation therapy. He had mild residual right hemiparesis. During childhood, he developed medically refractory focal epilepsy from the left hemisphere, requiring epilepsy surgery at age 10. A child presenting with sustained SVT can be at increased risk for intracardiac thrombi and stroke.