Jeong Yoon Choi

Reversible splenial abnormality in hypoglycemic encephalopathy

IntroductionLesions involving the splenium of the corpus callosum (SCC) have been rarely reported in cases of hypoglycemic brain injury.MethodsWe identified signal abnormalities in the SCC in three adult patients with hypoglycemic encephalopathy by using diffusion-weighted imaging (DWI) on a 1.5-T MR scanner. Repeat DWI was performed in all patients following a marked clinical improvement, and MR angiography and routine MRI were also performed. We examined each patient’s detailed medical history and blood laboratory tests in order to exclude other conditions causing similar SCC abnormalities.ResultsInitial DWI was performed during which each patient showed altered mental status that was attributed to profound hypoglycemia. We observed an identical pattern of DWI abnormality characterized by high signals in the SCC with apparent diffusion coefficient reductions that were reversed completely within several days following appropriate correction of hypoglycemia. T2-weighted or FLAIR images also showed no residual lesion in the SCC and MR angiography was normal in all patients.ConclusionThese case reports suggest that the SCC should be added to the list of selective vulnerability to hypoglycemia and that hypoglycemia, in turn, be included in the differential diagnosis of reversible SCC abnormalities.

Central paroxysmal positional nystagmus: Characteristics and possible mechanisms.

Objective: The diagnosis of central paroxysmal positional nystagmus (CPPN) is challenging, and the mechanisms require further elucidation. This study aimed to determine the characteristics and mechanisms of CPPN. Methods: Seventeen patients with CPPN were subjected to analyses of their clinical findings, MRI lesions, and oculographic data on spontaneous and positional nystagmus. Results: The direction of CPPN was mostly aligned with that of the head motion during the positioning, and 3 types of CPPN were identified: downbeat nystagmus on straight-head hanging, upbeat nystagmus on uprighting, and apogeotropic nystagmus during supine head roll test. The direction of CPPN was aligned with the vector sum of the rotational axes of the semicircular canals that were normally inhibited during the positioning. The intensity of evoked nystagmus was at its peak initially and then decreased exponentially over time. The time constants (TC) of the vertical CPPN ranged from 3 to 8 seconds, which corresponds to the TC of the vertical rotational vestibulo-ocular reflex. Sixteen patients (94.1%) showed more than one type of CPPN. Furthermore, persistent downbeat or apogeotropic positional nystagmus was associated in 11 patients (64.7%). Most patients with CPPN from a circumscribed brain lesion showed an involvement of the cerebellar nodulus or uvula. Conclusion: CPPN may be ascribed to enhanced responses of the vestibular afferents due to lesions involving the nodulus and uvula. CPPN could be differentiated from benign paroxysmal positional nystagmus by positional nystagmus induced in multiple planes, temporal patterns of nystagmus intensity, and associated neurologic findings suggestive of central pathologies.

Statin use in spontaneous intracerebral hemorrhage: a systematic review and meta-analysis.

Background Nonrandomized observational studies have been conducted to evaluate the effects of statins on clinical outcomes in patients with intracerebral hemorrhage. Several studies on the effects of statin administration in patients with intracerebral hemorrhage have been published recently, but the findings are inconsistent. Aim To evaluate the effects of statins administered prior to hospital admission and during hospitalization on mortality and functional outcomes in patients with intracerebral hemorrhage. Summary of review We searched for relevant literature using multiple comprehensive databases and performed a systematic review and meta-analysis. Sixteen studies met our selection criteria. Preintracerebral hemorrhage statin use was not associated with mortality (odds ratio: 0.90, 95% confidence interval: 0.63-1.28). However, patients who used statins prior to intracerebral hemorrhage had a decreased risk of mortality at three-months following symptom onset (odds ratio: 0.47, 95% confidence interval: 0.32-0.68) and an increased probability of good functional outcomes (odds ratio: 1.49, 95% confidence interval: 1.01-2.19), as compared with those who did not. In-hospital use of statins was associated with a low risk of mortality (odds ratio: 0.34, 95% confidence interval: 0.26-0.44) irrespective of preadmission statin use or postadmission timepoints. Additionally, we were unable to pool the data on statin withdrawal because of differences in study methodologies. Conclusions Although careful interpretation is necessary due to several study limitations, we have demonstrated that statin use in patients with intracerebral hemorrhage is likely associated with improved mortality and functional outcomes.

Brachial plexopathy following herpes zoster infection: Two cases with MRI findings

There are few reports of brachial plexopathy following the onset of a herpes zoster skin rash. Moreover, the MRI findings of zoster-induced brachial plexopathy have rarely been described. In the present study, we describe two cases of zoster brachial plexopathy and their MRI findings. MRI of the brachial plexus demonstrated T2 hyperintensity and contrast enhancement in the part of the brachial plexus that was compatible with both the clinical symptoms and the electrophysiological findings. Especially, MR imaging reflected the functional impairments more accurately than electrophysiological studies in the acute phase, during which MRI showed more extensive inflammatory involvement of the brachial plexus. MRI findings in the present cases suggest that, in addition to electrophysiological studies, MRI of the brachial plexus could provide valuable information for evaluating the location and extent of lesions and for understanding the pathophysiological mechanisms of zoster brachial plexopathy.

High free fatty acid level is associated with recurrent stroke in cardioembolic stroke patients

Objective: To determine whether the plasma level of free fatty acid (FFA) could be associated with recurrent stroke in cardioembolic (CE) stroke patients. Methods: We analyzed data from 669 acute ischemic stroke patients and examined the association between FFA concentration and recurrent stroke in CE stroke patients compared with non-CE stroke patients. Results: The baseline plasma FFA concentration (mEq/L) was approximately 1.5-fold higher in CE stroke patients (1.01 ± 0.63) than in non-CE stroke patients (0.72 ± 0.51). Multivariate logistic analysis showed that an increased level of FFA was significantly associated with CE stroke (hazard ratio [HR] 2.124, confidence interval [CI] 1.492–3.024). During the mean follow-up period of 25.4 months, a total of 56 (8.4%) patients experienced a stroke recurrence. The recurrence rate did not differ between patients with CE (10.5%) and non-CE (8.0%) stroke (p = 0.396). In CE stroke patients, an elevated baseline FFA concentration was independently associated with stroke recurrence (HR 2.711, CI 1.056–6.959). However, there was no association between FFA and stroke recurrence in non-CE stroke patients. Conclusion: In this retrospective registry-based observational study, CE stroke seemed to be associated with elevated plasma level of FFA. In addition, the present study suggested that an elevated FFA concentration could be a useful indicator for predicting recurrent stroke in CE stroke patients.

Symptomatic SUNCT Syndrome Associated With Ipsilateral Paranasal Sinusitis

Sinusitis has rarely been associated with short‐lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) syndrome. We describe a case of symptomatic SUNCT syndrome caused by sinusitis, which showed typical features of SUNCT syndrome. The patients symptoms completely resolved without recurrence after endoscopic sinus surgery followed by antibiotic treatment. We suggest that ipsilateral paranasal sinusitis accompanied by the spreading of inflammation through a dehiscence in the lamina papyracea could lead to the development of SUNCT syndrome.

Statins Improve Survival in Patients With Cardioembolic Stroke

Background and Purpose— The objective of this study was to investigate the potential benefits of statin therapy on mortality and stroke recurrence after cardioembolic stroke. Methods— In this retrospective observational study, we analyzed data from 535 patients with first-ever cardioembolic stroke. Patients were classified into nonstatin, low-potency statin, and high-potency statin groups. The primary outcomes were time to mortality and time to recurrent stroke. Results— The mean duration of follow-up was 22.2 months. The cumulative mortality rate was 7% at the end of the first year and 10% at the end of the third year. Statin therapy was independently associated with reduced mortality (hazard ratio, 0.237; 95% confidence interval, 0.080–0.703 for nonstatin versus low-potency statin; hazard ratio, 0.158; 95% confidence interval, 0.037–0.686 for nonstatin versus high-potency statin). Statin treatment did not affect the incidence of recurrent stroke in patients with cardioembolic stroke. Conclusions— Statin therapy could be associated with reduced mortality in patients with cardioembolic stroke.

Chronic kidney disease and intravenous thrombolysis in acute stroke: A systematic review and meta-analysis.

BACKGROUND The association between chronic kidney disease (CKD) and hemorrhagic complications or clinical outcomes in patients treated with intravenous (IV) thrombolytic agents is controversial. METHODS We searched multiple databases for studies on the association between CKD and symptomatic intracerebral hemorrhage (ICH) and/or clinical outcomes in acute stroke patients treated with IV tissue plasminogen activator (tPA). Observational studies that evaluated the association between CKD and outcomes after adjusting for other confounding factors were eligible. We assessed study quality and performed a meta-analysis. The main outcome was symptomatic ICH. The secondary outcomes were poor functional status at 3 months using the modified Rankin Scale, mortality at 3 months, and any ICH. RESULTS Seven studies were selected based on our eligibility criteria. Of 7168 patients treated with IV tPA, 2001 (27.9%) had CKD. Patients with CKD had a higher risk of symptomatic ICH and mortality [pooled odds ratio (OR) 1.56, 95% confidence interval (CI) 1.05-2.33 and pooled OR 1.70, 95% CI 1.03-2.81, respectively]. Patients with CKD were likely to have an increased risk of poor outcome at 3 months. There was no significant association between CKD and any ICH. CONCLUSIONS Chronic kidney disease may significantly affect symptomatic hemorrhagic complications and poor clinical outcomes following administration of IV tPA.

Abnormal Head Impulse Test in a Unilateral Cerebellar Lesion

Background The findings of head impulse tests (HIT) are usually normal in cerebellar lesions. Case Report A 46-year-old male presented with progressive dizziness and imbalance of 3 weeks duration. The patient exhibited catch-up saccades during bedside horizontal HIT to either side, which was more evident during the rightward HIT. However, results of bithermal caloric tests and rotatory chair test were normal. MRI revealed a lesion in the inferior cerebellum near the flocculus. Conclusions This case provides additional evidence that damage to the flocculus or its connections may impair the vestibulo-ocular reflex only during high-speed stimuli, especially when the stimuli are applied to the contralesional side. By observing accompanying cerebellar signs, the abnormal HIT findings caused by a cerebellar disorder can be distinguished from those produced by peripheral vestibular disorders.

Utility of the cutaneous silent period in the evaluation of carpal tunnel syndrome

OBJECTIVE This study investigates the utility of the cutaneous silent period (CuSP) in evaluating patients with carpal tunnel syndrome (CTS). METHODS The authors measured the CuSP from the abductor pollicis brevis muscle in 135 hands of patients with idiopathic CTS and 30 hands of age- and gender-matched controls. The patient group was further divided into subgroups according to the Canterbury scale. The differences in parameters between the patient subgroups and control group were analysed. A predetermined analysis looked at the possible correlation between the CuSP and symptom severity as measured by the Boston-Questionnaire. RESULTS The mean CuSP latencies in the patient group (72.4+/-16.1 ms) was significantly longer than the control group (64.6+/-13.4 ms; P=0.014), although there was no difference in the duration of the CuSP between groups. The duration and latency of the CuSP correlated to a higher severity on the Canterbury scale (r=0.273, P<0.001 and r=-0.164, P=0.036, respectively). However, the CuSP parameters did not correlate with the Boston-Questionnaire scores. CONCLUSIONS Although patients with CTS had significantly prolonged CuSP latency, the CuSP did not correlate with the clinical symptoms scale. SIGNIFICANCE The CuSP is a useful ancillary test to evaluate Adelta fibre function; however, it is not a reliable tool to quantify clinical severity.