Impact of stroke mechanism in acute basilar occlusion with reperfusion therapy

Objective

We aimed to evaluate the impact of underlying mechanism of basilar artery (BA) occlusion on the outcomes after endovascular therapy (EVT) for reperfusion and the outcome factors associated with each mechanism, and to identify radiologic parameters enabling to distinguish the underlying mechanism.

Methods

From a registry database, 194 consecutive patients with acute BA occlusion who underwent EVT were analyzed. Stroke mechanism, classified into in situ atherosclerotic thrombosis (ISAT) and embolism, clot sign location profiles in pre‐angiography magnetic resonance image (MRI), parameters of angiography and EVT, and reperfusion were assessed. Poor outcome was defined as a modified Rankin‐Scale score at 90 days of 3–6.

Results

The mean age was 68.8±11.8 years (range 21–92 years) and seventy‐eight (40.2%) were female patients. 102 (52.6%) patients were classified into an embolism mechanism and 92 (47.4%) into an ISAT mechanism. Overall, ISAT mechanism compared with embolism was significantly associated with poor outcomes (P = 0.002), along with the NIHSS scores, reperfusion status, and collateral status. In the embolism group, reperfusion (P = 0.001), NIHSS scores (P < 0.001), and onset‐to‐treatment time (P = 0.030) were significant outcome factors. However, in the ISAT group, baseline collateral status (P = 0.001) and NIHSS scores (P < 0.001) were significant outcome factors. A clot sign at the distal BA segment on pre‐angiography MRI was strongly associated with embolism mechanism (P < 0.001).

Interpretation

Stroke mechanism has a major influence on outcomes, and outcome predictors differ according to the underlying mechanism in acute BA occlusion with EVT. Clot sign profile on pre‐angiography MRI might be useful to determine the underlying mechanism.

Cystatin C, a potential marker for cerebral microvascular compliance, is associated with white-matter hyperintensities progression

Cerebral white matter hyperintensities (WMHs) are central MRI markers of the brain aging process, but the mechanisms for its progression remain unclear. In this study, we aimed to determine whether the baseline serum cystatin C level represented one mechanism underlying WMH progression, and whether it was associated with the long-term progression of cerebral WMH volume in MRI. 166 consecutive individuals who were ≥50 years of age and who underwent initial/follow-up MRI evaluations within an interval of 34–45 months were included. Serum cystatin C level, glomerular-filtration rate (GFR), and other laboratory parameters were measured at their initial evaluation and at the end of follow-up. Cerebrovascular risk factors, medications, and blood-pressure parameters were also reviewed. WMH progression rate was measured by subtracting WMH volume at baseline from that at the follow-up using volumetric analysis, divided by the MRI intervals. At baseline, WMH volume was 9.61±13.17 mL, mean GFR was 77.3±22.8 mL/min, and mean cystatin C level was 0.92±0.52 mg/L. After 37.9±3.4 months, the change in WMH volume was 3.64±6.85 mL, the progression rate of WMH volume was 1.18±2.28 mL/year, the mean ΔGFR was 2.4±7.9 mL/min, and the mean Δcystatin C was 0.03±0.34 mg/L. The progression rate of WMH volume was linearly associated with cystatin C level (B coefficient = 0.856; 95% confidence interval [CI] 0.174−1.538; P = 0.014), along with the baseline WMH volume (B = 0.039; 95% CI 0.019−0.059; P<0.001), after adjusting for the conventional vascular risk factors, laboratory parameters, medication profiles, and GFR. Especially, patients with a baseline level of cystatin C ≥1.00 mg/L exhibited a much higher progression rate of WMH as compared with those with a baseline level of cystatin C <1.00 mg/L (1.60±1.91 mL/year vs. 0.82±1.63 mL/year, P = 0.010). We concluded that serum cystatin C level is independently associated with the long-term progression rate of the cerebral WMH volume. Therefore, serum cystatin C level might predict the progression of cerebral WMH.

Central Nervous System Infection Associated with Orientia tsutsugamushi in South Korea

Orientia tsutsugamushi is a major cause of vector-borne infection in Asia. Prompt recognition and appropriate treatment are crucial because of its potentially fatal complications and lack of response to beta-lactam antibiotics. The present study retrospectively evaluated the clinical characteristics and laboratory findings of 16 patients with scrub typhus-related central nervous system (CNS) infections. Single titers ≥ 1:40 of total serum antibodies against O. tsutsugamushi detected by an indirect immunofluorescent assay were considered as positive results. The median age was 35.5 (range, 14-72) years, and 10 (62.5%) patients were female. The most common symptoms were headache (81.3%) and fever (81.3%). Eschar formation was found in three (18.8%) patients. Among patients with encephalitis, seizures and altered consciousness occurred in five (83.3%) and four (66.7%) patients, respectively. An abnormal liver function was noted in seven (43.8%) patients. The median antibody titer was 1:120 (range, 1:40-1:2,560). Typical cerebrospinal fluid profiles were lymphocytic pleocytosis, mild protein elevations, and normal glucose levels. All patients received an empirical treatment with doxycycline and most (93.8%) of them recovered without neurological sequelae. None of the patients reported side effects of the doxycycline treatment. An empirical treatment with doxycycline is needed in patients with CNS infections in scrub typhus endemic areas.

Efficacy of single or combined midodrine and pyridostigmine in orthostatic hypotension

OBJECTIVE

To evaluate the long-term (for up to 3 months) efficacy and safety of single or combined therapy with midodrine and pyridostigmine for neurogenic orthostatic hypotension (OH).

METHODS

This was a randomized, open-label clinical trial. In total, 87 patients with symptomatic neurogenic OH were enrolled and randomized to receive 1 of 3 treatments: midodrine only, pyridostigmine only, or midodrine + pyridostigmine. The patients were followed up at 1 and 3 months after treatment. The primary outcome measures were improvement in orthostatic blood pressure (BP) drop at 3 months. Secondary endpoints were improvement of the orthostatic BP drop at 1 month and amelioration of the questionnaire score evaluating OH-associated symptoms.

RESULTS

Orthostatic systolic and diastolic BP drops improved significantly at 3 months after treatment in all treatment groups. Orthostatic symptoms were significantly ameliorated during the 3-month treatment, and the symptom severity was as follows: midodrine only < midodrine + pyridostigmine < pyridostigmine only group. Mild to moderate adverse events were reported by 11.5% of the patients.

CONCLUSIONS

Single or combination treatment with midodrine and pyridostigmine was effective and safe in patients with OH for up to 3 months. Midodrine was better than pyridostigmine at improving OH-related symptoms.

CLINICALTRIALSGOV IDENTIFIER

NCT02308124.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that for patients with neurogenic OH, long-term treatment with midodrine alone, pyridostigmine alone, or both midodrine and pyridostigmine is safe and has similar effects in improving orthostatic BP drop up to 3 months.

Neurovascular Cell Sheet Transplantation in a Canine Model of Intracranial Hemorrhage

Cell-based therapy for intracerebral hemorrhage (ICH) has a great therapeutic potential. However, methods to effectively induce direct regeneration of the damaged neural tissue after cell transplantation have not been established, which, if done, would improve the efficacy of cell-based therapy. In this study, we aimed to develop a cell sheet with neurovasculogenic potential and evaluate its usefulness in a canine ICH model. We designed a composite cell sheet made of neural progenitors derived from human olfactory neuroepithelium and vascular progenitors from human adipose tissue-derived stromal cells. We also generated a physiologic canine ICH model by manually injecting and then infusing autologous blood under arterial pressure. We transplanted the sheet cells (cell sheet group) or saline (control group) at the cortex over the hematoma at subacute stages (2 weeks from ICH induction). At 4 weeks from the cell transplantation, cell survival, migration, and differentiation were evaluated. Hemispheric atrophy and neurobehavioral recovery were also compared between the groups. As a result, the cell sheet was rich in extracellular matrices and expressed neurotrophic factors as well as the markers for neuronal development. After transplantation, the cells successfully survived for 4 weeks, and a large portion of those migrated to the perihematomal site and differentiated into neurons and pericytes (20% and 30% of migrated stem cells, respectively). Transplantation of cell sheets alleviated hemorrhage-related hemispheric atrophy (p = 0.042) and showed tendency for improving functional recovery (p = 0.062). Therefore, we concluded that the cell sheet transplantation technique might induce direct regeneration of neural tissue and might improve outcomes of intracerebral hemorrhage.

The c-Abl inhibitor, nilotinib, as a potential therapeutic agent for chronic cerebellar ataxia

Nilotinib is a potent inhibitor of tyrosine kinase BCR-ABL that penetrates the blood-brain barrier. To evaluate the effect of nilotinib in chronic cerebellar ataxia, twelve patients with chronic cerebellar ataxia nonresponsive to other treatment options (modified Rankin scale [mRS] scores: >2) and received nilotinib therapy (daily doses: 150-300mg) for >4 (range 5-16) weeks were reviewed. At follow-up, improved mRS scores were found in 7/12 (58.3%) patients and favorable mRS scores (≤2) were found in 6/12 (50.0%) patients. No severe adverse event was observed. Atrophy in the cerebellar vermis appeared to be negatively associated with favorable outcomes.

Progression of Cerebral White Matter Hyperintensities and the Associated Sonographic Index

Purpose To evaluate the relationship between penetrating arterial pulsation and the progression of white matter hyperintensities (WMHs) by using the sonographic resistance index (RI) along the M1 segment of the middle cerebral artery (MCA). Materials and Methods The study design was approved by the institutional review board of Seoul National University Hospital. The study included 450 individuals who had undergone initial transcranial Doppler (TCD) sonography and magnetic resonance imaging, with follow-up imaging performed within 34-45 months, and who had no stenosis of 30% or more in the internal carotid artery or MCA or a history of stroke other than an old lacunar infarction. MRIR was defined as distal RI divided by proximal RI, where the distance between proximal MI and distal M1 was approximately 20 mm based on TCD evaluation. WMH progression was quantitatively evaluated by subtracting WMH volume at baseline from WMH volume at follow-up. Results At baseline, mean MRIR was 0.974 ± 0.045 (standard deviation), and mean WMH volume was 9.66 mL ± 14.54. After a mean of 38.3 months ± 3.4, the WMH volume change was 4.06 mL ± 7.35. WMH volume change was linearly associated with MRIR (r = 0.328, P < .001), along with the baseline WMH volume (r = 0.433, P < .001) and mean MCA pulsatility index (r = 0.275, P = .037). MRIR values greater than or equal to 1.000 were associated with a greater increase in WMH volume (P < .001). Conclusion MRIR might reflect the pulsation of penetrating arteries and is independently associated with WMH progression. ^© RSNA, 2017 Online supplemental material is available for this article.

Iliacus abscess with radiculopathy mimicking herniated nucleus pulposus: Additional diagnostic value of magnetic resonance imaging

An iliacus abscess is an extremely rare cause of low back pain. With an iliacus abscess, the classical signs seen with a psoas abscess are frequently absent. Therefore, a timely diagnosis at the initial visit is difficult and inadequate treatment usually results in high mortality. Here, we report the case of 19-year-old man who presented with acute low back pain with radiculopathy and was ultimately diagnosed with an iliacus muscle abscess.

The use of continuous negative pressure after open debridement for septic arthritis of the shoulder

AIMS

The treatment of septic arthritis of the shoulder is challenging. The infection frequently recurs and the clinical outcome can be very poor. We aimed to review the outcomes following the use of continuous negative pressure after open debridement with a large diameter drain in patients with septic arthritis of the shoulder.

PATIENTS AND METHODS

A total of 68 consecutive patients with septic arthritis of the shoulder underwent arthrotomy, irrigation and debridement. A small diameter suction drain was placed in the glenohumeral joint and a large diameter drain was placed in the subacromial space with continuous negative pressure of 15 cm H2O. All patients received a standardised protocol of antibiotics for a mean of 5.1 weeks (two to 11.1).

RESULTS

Negative pressure was maintained for a mean of 24 days (14 to 32). A total of 67 patients (98.5%) were cured without further treatment being required. At a mean follow-up of 14 months (three to 72), the mean forward flexion was 123° (80° to 140°) and the mean external rotation was 28°(10° to 40°) in those with a rotator cuff tear, and 125° (85° to 145°) and 35° (15° to 45°) in those without a rotator cuff tear.

CONCLUSION

Continuous negative pressure, following open arthrotomy, irrigation and debridement, was effective in treating septic arthritis of the shoulder. The rate of recurrence was significantly lower than with conventional treatment involving arthroscopic or open debridement reported in the literature. Functional outcomes, even in patients with rotator cuff tears, were excellent.

TAKE HOME MESSAGE

Continuous negative pressure is effective in treating septic arthritis of the shoulder. Cite this article: Bone Joint J 2016;98-B:660-5.

A Systematic Review on Sasang Constitutional Type-Associated Susceptibility to Disorders in Korea

BACKGROUND/OBJECTIVE

Sasang constitutional medicine is a component of traditional Korean medicine that classifies individuals into four Sasang constitutional types (SCTs) by their physical and psychological traits. Each SCT is known to show different susceptibilities to disorders. This systematic review investigated the effect of SCT as a risk factor for various disorders.

METHODS

A systematic literature survey was conducted by searching seven databases for all articles on the prevalence rates of disorders according to SCT and sex.

RESULTS

From 14,272 relevant articles, 15 studies (13 disorders) were ultimately identified to verify different prevalence rates by SCT. Of the 13 disorders, 6 (prehypertension, general obesity, abdominal obesity, metabolic syndrome, diabetes mellitus, and irritable bowel syndrome [IBS]) had a significantly different prevalence by SCT. Metabolic syndrome and its associated disorders showed the highest prevalence in Taeumin-type individuals, whereas IBS was most prevalent in Soeumin-type individuals. In general, these findings were consistent with the results obtained in an analysis of male and female participants.

CONCLUSIONS

This study revealed that susceptibility to disorders was affected by SCT to some extent. Further studies are needed to determine the concrete features of SCT-related susceptibility, which may be helpful in preventive medicine with Sasang constitutional practice.

Tocilizumab in Autoimmune Encephalitis Refractory to Rituximab: An Institutional Cohort Study

A considerable portion of autoimmune encephalitis (AE) does not respond to conventional immunotherapies and subsequently has poor outcomes. We aimed to determine the efficacy of tocilizumab, an anti-interleukin-6 antibody, in rituximab-refractory AE compared with other treatment options. From an institutional cohort of AE, 91 patients with inadequate clinical response to first-line immunotherapy and following rituximab were retrospectively reviewed. Patients were grouped according to their further immunotherapy strategies. Thirty (33.0 %) patients were included in the tocilizumab group, 31 (34.0 %) in the additional rituximab group, and 30 (33.0 %) in the observation group. Outcomes were defined as the favorable modified Rankin Scale scores (≤2) at 1 and 2 months from the initiation of each treatment strategy and at the last follow-up. Favorable clinical response (improvement of the modified Rankin Scale scores by ≥ 2 points or achievement of the mRS scores ≤ 2) at the last follow-up was also analyzed. The tocilizumab group showed more frequent favorable mRS scores at 2 months from treatment initiation and at the last follow-up compared with those at the relevant time points of the remaining groups. The majority (89.5 %) of the patients with clinical improvement at 1 month from tocilizumab treatment maintained a long-term favorable clinical response. No serious adverse effects of rituximab or tocilizumab were reported. Therefore, we suggest that tocilizumab might be a good treatment strategy for treating AE refractory to conventional immunotherapies and rituximab. The tocilizumab-mediated clinical improvement manifests as early at 1 month after treatment initiation.

Spinodally Decomposed PbSe-PbTe Nanoparticles for High-Performance Thermoelectrics: Enhanced Phonon Scattering and Unusual Transport Behavior

Dramatic enhancements in the figure of merit have been obtained in bulk thermoelectric materials by doping, band engineering, and nanostructuring. Especially, in p-type thermoelectrics, high figure of merits near 2.0 have been reported in a few papers through the reduction in lattice thermal conductivity and the advancement in power factors. However, there exists no report on the n-type systems showing high figure of merits because of their intrinsically low Seebeck coefficients. Here, we demonstrate that a nanostructured bulk n-type thermoelectric material that was assembled by sintering spinodally decomposed lead chalcogenide nanoparticles having a composition of PbSe0.5Te0.5 reaches a high figure of merit of 1.85. The spinodally decomposed nanoparticles permit our thermoelectric material to have extremely low lattice thermal conductivity and a high power factor as a result of nanostructuring, electronic optimization, insertion of an impurity phase and phase change in local areas. We propose that this interesting concept would be one of the promising approaches that overcome limitation arising from the fact that most parameters in the figure of merit are closely correlated.

A dose monitoring system for dental radiography

Purpose

The current study investigates the feasibility of a platform for a nationwide dose monitoring system for dental radiography. The essential elements for an unerring system are also assessed.

Materials and Methods

An intraoral radiographic machine with 14 X-ray generators and five sensors, 45 panoramic radiographic machines, and 23 cone-beam computed tomography (CBCT) models used in Korean dental clinics were surveyed to investigate the type of dose report. A main server for storing the dose data from each radiographic machine was prepared. The dose report transfer pathways from the radiographic machine to the main sever were constructed. An effective dose calculation method was created based on the machine specifications and the exposure parameters of three intraoral radiographic machines, five panoramic radiographic machines, and four CBCTs. A viewing system was developed for both dentists and patients to view the calculated effective dose. Each procedure and the main server were integrated into one system.

Results

The dose data from each type of radiographic machine was successfully transferred to the main server and converted into an effective dose. The effective dose stored in the main server is automatically connected to a viewing program for dentist and patient access.

Conclusion

A patient radiation dose monitoring system is feasible for dental clinics. Future research in cooperation with clinicians, industry, and radiologists is needed to ensure format convertibility for an efficient dose monitoring system to monitor unexpected radiation dose.

Fundus autofluorescence imaging patterns in central serous chorioretinopathy according to chronicity

PurposeTo investigate the time-period characteristics associated with morphologic changes in central serous chorioretinopathy (CSC) using fundus autofluorescence (FAF).Patients and methodsRetrospective, cross-sectional observational case series. Patients were classified into three groups: acute and chronic according to the onset of subjective symptoms of 6 weeks and sequelae patients who have history and symptoms but no serous retinal detachment (SRD). We compared FAF images to obtain characteristic findings according to the chronicity.ResultsA total of 52 eyes were included in this study. Acute CSC eyes were characterized by decreased FAF intensity at the leakage point in 13/22 eyes (56.5%) and staining patterns with various levels of fluorescence signal (hyperautofluorescent (10 eyes, 43.5%), hypoautofluorescent (1 eye, 4.3%), and minimal changes (12 eyes, 52.2%)) in the area of SRD. In chronic CSC eyes, hyperautofluorescent (14 eyes, 63.6%) or minimal changes (8 eyes, 36.4%) were observed in the area of SRD. Discrete dots with increased FAF intensity were observed in chronic CSC eyes (P<0.001). Eyes with sequelae of CSC had mixed FAF patterns over areas of retinal pigment epithelium (RPE) atrophy in seven eyes (100%, P<0.001)) and descending tracts which showed various FAF intensities according to the RPE and photoreceptor status (P<0.001).ConclusionFAF imaging patterns in CSC eyes differ according to the course of the disease, reflecting RPE and outer retinal changes. Detailed investigation using FAF could help to estimate the duration of CSC and determine the proper treatment modality.

Rituximab treatment for autoimmune limbic encephalitis in an institutional cohort

OBJECTIVE

To determine efficacy and safety of rituximab treatment as a second-line immunotherapy treatment for autoimmune limbic encephalitis (ALE) and to determine factors associated with functional improvement and favorable outcome following rituximab treatment.

METHODS

We recruited 80 patients with ALE who were treated with rituximab as a second-line immunotherapy from the Korea Autoimmune Synaptic and Paraneoplastic Encephalitis Registry and reviewed 81 patients without rituximab as a control. We grouped patients according to the detection or type of antibodies; in addition, we evaluated clinical, laboratory, first-line immunotherapy, and rituximab treatment profiles and defined main outcomes as improvements on the modified Rankin Scale (mRS) score and a favorable mRS score (0-2) at the last follow-up.

RESULTS

Functional improvement occurred more frequently in the rituximab group compared to the control group. In the rituximab group, 30 (37.5%) patients had synaptic autoantibodies, 15 (18.8%) in the paraneoplastic autoantibodies, and 35 (43.8%) were antibody-negative. The effect of rituximab was the same regardless of autoantibody status. Additional monthly rituximab therapy and partial response to first-line immunotherapies were associated with mRS score improvements, as well as favorable mRS scores. mRS scores of 4-6 as the worst neurologic status predicted an unfavorable mRS score. There were no reported serious infusion-related or infectious adverse effects of rituximab.

CONCLUSIONS

Rituximab is effective and safe as a second-line immunotherapy for ALE, regardless of autoantibody status. Additional monthly rituximab therapy might potentiate the efficacy of rituximab.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that rituximab improves mRS scores for patients with autoimmune limbic encephalitis who fail first-line therapy.