Deep Learning-Based Automatic Classification of Ischemic Stroke Subtype Using Diffusion-Weighted Images.

BACKGROUND AND PURPOSE: Accurate classification of ischemic stroke subtype is important for effective secondary prevention of stroke. We used diffusion-weighted image (DWI) and atrial fibrillation (AF) data to train a deep learning algorithm to classify stroke subtype. METHODS: Model development was done in 2,988 patients with ischemic stroke from three centers by using U-net for infarct segmentation and EfficientNetV2 for subtype classification. Experienced neurologists (n=5) determined subtypes for external test datasets, while establishing a consensus for clinical trial datasets. Automatically segmented infarcts were fed into the model (DWI-only algorithm). Subsequently, another model was trained, with AF included as a categorical variable (DWI+AF algorithm). These models were tested: (1) internally against the opinion of the labeling experts, (2) against fresh external DWI data, and (3) against clinical trial dataset. RESULTS: In the training-and-validation datasets, the mean (±standard deviation) age was 68.0±12.5 (61.1% male). In internal testing, compared with the experts, the DWI-only and the DWI+AF algorithms respectively achieved moderate (65.3%) and near-strong (79.1%) agreement. In external testing, both algorithms again showed good agreements (59.3%-60.7% and 73.7%-74.0%, respectively). In the clinical trial dataset, compared with the expert consensus, percentage agreements and Cohen's kappa were respectively 58.1% and 0.34 for the DWI-only vs. 72.9% and 0.57 for the DWI+AF algorithms. The corresponding values between experts were comparable (76.0% and 0.61) to the DWI+AF algorithm. CONCLUSION: Our model trained on a large dataset of DWI (both with or without AF information) was able to classify ischemic stroke subtypes comparable to a consensus of stroke experts.

Independent effect of Aß burden on cognitive impairment in patients with small subcortical infarction.

BACKGROUND: The effect of amyloid-ß (Aß) on cognitive impairment in patients with small subcortical infarction remains controversial, although a growing body of evidence shows a substantial overlap between Alzheimer's disease (AD) and subcortical ischemic vascular dementia, another form of cerebral small vessel disease (cSVD). Therefore, we investigated the relationships between Aß positivity and the development of post-stroke cognitive impairment (PSCI) in patients with small subcortical infarction. METHODS: We prospectively recruited 37 patients aged ≥ 50 years, with first-ever small subcortical infarction, who underwent amyloid positron emission tomography, 3 months after stroke at Korea University Guro Hospital. We also enrolled CU participants matched for age and sex with stroke patients for comparison of Aß positivity. Patients were followed up at 3 and 12 months after the stroke to assess cognitive decline. Logistic and linear mixed-effect regression analyses were performed to identify the effect of Aß positivity on PSCI development and long-term cognitive trajectories. RESULTS: At 3 months after stroke, 12/37 (32.4%) patients developed PSCI, and 11/37 (29.7%) patients had Aß deposition. Aß positivity (odds ratio [OR] = 72.2, p = 0.024) was predictive of PSCI development regardless of cSVD burden. Aß positivity (ß = 0.846, p = 0.014) was also associated with poor cognitive trajectory, assessed by the Clinical Dementia Rating-Sum of Box, for 1 year after stroke. CONCLUSIONS: Our findings highlight that Aß positivity is an important predictor for PSCI development and cognitive decline over 1 year. Furthermore, our results provide evidence that anti-AD medications may be a strategy for preventing cognitive decline in patients with small subcortical infarctions.

Functional connectivity and network analysis in adolescents with major depressive disorder showing suicidal behavior.

BACKGROUND: This study aimed to gather a homogeneous sample of adolescent patients to analyze the differences in functional connectivity and brain network parameters between suicidal and non-suicidal major depressive disorder (MDD) patients using a data-driven whole-brain approach. METHODS: Patients recruited at the psychiatry department of Korea University Guro Hospital from November 2014 to March 2020 were diagnosed with MDD, were 13-18 years old, had IQ scores >80, had no family history of psychotic or personality disorders, had no smoking or alcohol consumption history, and were drug-naïve to psychotropic medication. Depressive symptoms were assessed using the Hamilton Depression Rating Scale and the Children's Depression Inventory. Structural and functional MRI scans were conducted and analyzed using the CONN toolbox. RESULTS: Of 74 enrolled patients, 62 were analyzed. Regions of interest (ROIs) showing higher betweenness centrality in non-suicidal patients were the left superior temporal gyrus and left supramarginal gyrus. ROIs showing higher betweenness centrality in suicidal patients were the right hippocampus, left intracalcarine cortex, right inferior temporal gyrus, and the lateral visual network. Suicidal patients also showed different resting state functional connectivity profiles from non-suicidal patients. LIMITATIONS: Small sample size. CONCLUSION: Suicidal patients may overthink and overvalue future risks while having a more negatively biased autobiographical memory. Social cognition and the ability to overcome egocentricity bias seem to weaken. Such features can disrupt cognitive recovery and resilience, leading to more suicidal behaviors. Therefore, increased suicidality is not acquired, but is an innate trait.

Altered Functional Connectivity of the Nucleus Accumbens and Amygdala in Cyber Addiction: A Resting State Functional Magnetic Resonance Imaging Study.

Objective: Cyber addiction, which is more vulnerable in adolescents, is defined as the excessive use of computers and the Internet that causes serious psychological, social, and physical problems. In this study, we investigated the resting-state functional connectivity (rsFC) in adolescents with cyber addiction. Methods: We collected and analyzed resting-state functional neuroimaging data of 20 patients with cyber addiction, aged 13-18 years, and 27 healthy controls. Based on previous studies, the seed regions included the dorsolateral prefrontal cortex, medial orbitofrontal cortex, lateral orbitofrontal cortex, dorsal anterior cingulate cortex, insula, hippocampus, amygdala, nucleus accumbens, and the ventral tegmental area. Seed-to-voxel analyses were performed to investigate the differences between patients and healthy controls. A correlation analysis between rsFC and cyber addiction severity was also performed. Results: Patients with cyber addiction showed the following characteristics: increased positive rsFC between the left insular-right middle temporal gyrus; increased positive rsFC between the right hippocampus-right precentral gyrus; increased positive rsFC between the right amygdala-right precentral gyrus and right parietal operculum cortex; increased negative rsFC between the left nucleus accumbens-right cerebellum crus II and right cerebellum VI. Conclusion: Adolescents with cyber addiction show altered functional connectivity during the resting state. The findings of this study may help us better understand the neuropathology of cyber addiction in adolescents.

Cerebello-thalamofrontal dysconnectivity in paroxysmal kinesigenic dyskinesia: A resting-state fMRI study.

INTRODUCTION: The pathophysiology of paroxysmal kinesigenic dyskinesia (PKD) remains elusive to date; however, several lines of evidence from neuroimaging studies suggest involvement of the basal ganglia-thalamocortical network in PKD. We combined fractional amplitude of low-frequency fluctuation (fALFF) and seed-based functional connectivity (FC) analyses in order to comprehensively investigate intrinsic brain activity alterations and their relationships with disease severity in patients with idiopathic PKD. METHODS: Resting-state functional MRI data were obtained and processed in 34 PKD patients and 34 matched controls. fALFF and seed-based FC maps were computed and compared between patients and controls. Linear regression analysis was further performed between regional fALFF values or FC strengths and clinical parameters in patients. RESULTS: PKD patients had a significant increase in fALFF in bilateral thalamus and cerebellum compared with controls. FC analysis seeding at the thalamic clusters revealed significant FC increases in motor cortex and supplementary motor area in PKD patients relative to controls. Longer disease duration was associated with increasing FC strength between the thalamus and motor cortex. CONCLUSION: We have provided evidence for abnormal intrinsic activity in the cerebello-thalamic circuit and increased thalamofrontal FC in PKD patients, implicating interictal cerebello-thalamofrontal dysconnectivity in the pathophysiology of PKD. Given the increasing FC strength in proportion to disease duration, the thalamofrontal hyperconnectivity might reflect either a consequence of recurrent dyskinesias on the brain or an innate pathology causing dyskinesias in PKD.

Monitoring Radiation Doses during Diagnostic and Therapeutic Neurointerventional Procedures: Multicenter Study for Establishment of Reference Levels.

PURPOSE: To assess patient radiation doses during diagnostic and therapeutic neurointerventional procedures from multiple centers and propose dose reference level (RL). MATERIALS AND METHODS: Consecutive neurointerventional procedures, performed in 22 hospitals from December 2020 to June 2021, were retrospectively studied. We collected data from a sample of 429 diagnostic and 731 therapeutic procedures. Parameters including dose-area product (DAP), cumulative air kerma (CAK), fluoroscopic time (FT), and total number of image frames (NI) were obtained. RL were calculated as the 3rd quartiles of the distribution. RESULTS: Analysis of 1160 procedures from 22 hospitals confirmed the large variability in patient dose for similar procedures. RLs in terms of DAP, CAK, FT, and NI were 101.6 Gy·cm2, 711.3 mGy, 13.3 minutes, and 637 frames for cerebral angiography, 199.9 Gy·cm2, 3,458.7 mGy, 57.3 minutes, and 1,000 frames for aneurysm coiling, 225.1 Gy·cm2, 1,590 mGy, 44.7 minutes, and 800 frames for stroke thrombolysis, 412.3 Gy·cm2, 4,447.8 mGy, 99.3 minutes, and 1,621.3 frames for arteriovenous malformation (AVM) embolization, respectively. For all procedures, the results were comparable to most of those already published. Statistical analysis showed male and presence of procedural complications were significant factors in aneurysmal coiling. Male, number of passages, and procedural combined technique were significant factors in stroke thrombolysis. In AVM embolization, a significantly higher radiation dose was found in the definitive endovascular cure group. CONCLUSION: Various RLs introduced in this study promote the optimization of patient doses in diagnostic and therapeutic interventional neuroradiology procedures. Proposed 3rd quartile DAP (Gy·cm2) values were 101.6 for diagnostic cerebral angiography, 199.9 for aneurysm coiling, 225.1 for stroke thrombolysis, and 412.3 for AVM embolization. Continual evolution of practices and technologies requires regular updates of RLs.

Altered trigeminothalamic spontaneous low-frequency oscillations in migraine without aura: a resting-state fMRI study.

BACKGROUND: Recent resting-state fMRI studies demonstrated functional dysconnectivity within the central pain matrix in migraineurs. This study aimed to investigate the spatial distribution and amplitude of low-frequency oscillations (LFOs) using fractional amplitude of low-frequency fluctuation (fALFF) analysis in migraine patients without aura, and to examine relationships between regional LFOs and clinical variables. METHODS: Resting-state fMRI data were obtained and preprocessed in 44 migraine patients without aura and 31 matched controls. fALFF was computed according to the original method, z-transformed for standardization, and compared between migraineurs and controls. Correlation analysis between regional fALFF and clinical variables was performed in migraineurs as well. RESULTS: Compared with controls, migraineurs had significant fALFF increases in bilateral ventral posteromedial (VPM) thalamus and brainstem encompassing rostral ventromedial medulla (RVM) and trigeminocervical complex (TCC). Regional fALFF values of bilateral VPM thalamus and brainstem positively correlated with disease duration, but not with migraine attack frequency or Migraine Disability Assessment Scale score. CONCLUSIONS: We have provided evidence for abnormal LFOs in the brainstem including RVM/TCC and thalamic VPM nucleus in migraine without aura, implicating trigeminothalamic network oscillations in migraine pathophysiology. Our results suggest that enhanced LFO activity may underpin the interictal trigeminothalamic dysrhythmia that could contribute to the impairments of pain transmission and modulation in migraine. Given our finding of increasing fALFF in relation to increasing disease duration, the observed trigeminothalamic dysrhythmia may indicate either an inherent pathology leading to migraine headaches or a consequence of repeated attacks on the brain.

Prospective study on resting state functional connectivity in adolescents with major depressive disorder after antidepressant treatment.

Recent advances in functional magnetic resonance imaging (fMRI) have resulted in many studies on resting-state functional connectivity (rsFC) in depressed patients. Previous studies have shown alterations between multiple brain areas, such as the prefrontal cortex, anterior cingulate cortex, and basal ganglia, but there are very few prospective studies with a longitudinal design on adolescent depression patients. We therefore investigated the change in positive rsFC in a homogeneous drug-naïve adolescent group after 12 weeks of antidepressant treatment. Functional neuroimaging data were collected and analyzed from 32 patients and 27 healthy controls. Based on previous literature, the amygdala, anterior cingulate cortex (ACC), insula, hippocampus, and dorsolateral prefrontal cortex (DLPFC) were selected as seed regions. Seed-to-voxel analyses were performed between pre- and post-treatment states as well as between the patients and controls at baseline. The positive rsFC between the right DLPFC and the left putamen/right frontal operculum were shown to be higher in patients than in the controls. The positive rsFC between the left DLPFC and left putamen/left lingual gyrus was also higher in the patients than in the controls. The positive rsFC between the right dorsal ACC and the left precentral gyrus had reduced after the 12-week antidepressant treatment. Regions involved in the frontolimbic circuit showed changes in the positive rsFC in the depressed adolescents as compared to in the healthy controls. There were also significant changes in the positive rsFC after 12-weeks of antidepressant treatment. The involved regions were associated with emotional regulation, cognitive functioning, impulse control, and visual processing.

Prospective study on microstructure in medication-naïve adolescents with first-episode major depressive disorder.

BACKGROUND: Major depressive disorder (MDD) is one of the most prevalent mental disorders during adolescence, and early diagnosis and treatment are important. We aimed to characterize the microstructure of the brain in medication-naïve adolescents with first-episode MDD. METHODS: Patients with MDD (N = 31) and healthy controls (N = 27) participated in this study and severity of depressive symptoms, duration of untreated depressive episode, demographic data, and diffuse tensor imaging data were collected. A comparative analysis of patients and healthy controls was performed, and the effect of medication on the brain`s integrity was investigated through comparison before and after 3 months of treatment in the patient group. Tract-based spatial statistics was used for diffusion tensor image analysis. RESULTS: In the patient group, functional anisotropy (FA) values were significantly higher at the genu of the corpus callosum, body of the corpus callosum, and right anterior corona radiata than in healthy controls. After 3 months of treatment, FA values were significantly decreased in the left anterior limb of the internal capsule, left posterior limb of the internal capsule, and left superior longitudinal fasciculus. LIMITATIONS: The sample size is relatively small and 3-month treatment period was relatively short. CONCLUSION: FA values of patients with MDD were increased compared to healthy controls and decreased after treatment. These results suggested that pharmacological treatments in the early stages of MDD might restore the brain`s integrity.

Correlation of Aneurysmal Wall Enhancement of Unruptured Intracranial Aneurysms on High-Resolution Vessel-Wall Imaging With Clinical Indices and Surgical Findings.

BACKGROUND: Many physicians consider aneurysmal wall enhancement (AWE) on high resolution-vessel wall imaging (HR-VWI) as an imaging biomarker of unstable unruptured intracranial aneurysms (UIAs). OBJECTIVE: To evaluate the clinical value of different AWE signal intensities (SIs) by assessing the correlation between the AWE SIs and surgical findings and rupture risk assessment tools. METHODS: Twenty-six patients with 34 aneurysms who underwent surgical clipping were included. The corrected AWE SI was calculated by comparing T1-weighted images with post-gadolinium enhanced T1-weighted images. The correlation of AWE with the population, hypertension, age, size of aneurysm, earlier subarachnoid hemorrhage from another aneurysm, site of aneurysm (PHASES) and earlier subarachnoid hemorrhage, location of the aneurysm, age >60 years, population, size of the aneurysm, shape of the aneurysm (ELAPSS) scores was evaluated using correlation and linear regression analysis. To quantify the surgical findings, the average color value of the aneurysms expressed in the CIELCh system was measured. Δh, color difference from yellow, was used for statistical analysis. RESULTS: The mean age of the patients and aneurysm size were 64.08 yr and 6.95 mm, respectively. The mean AWE SI, PHASES and ELAPSS scores, and Δh were 22.30, 8.41, 20.32, and 41.36, respectively. The coefficients of correlation of AWE SI with the PHASES and ELAPSS scores and Δh were 0.526, 0.563, and -0.431. We found that the AWE SI affected the PHASES (ß = 0.430) and ELAPSS scores (ß = 0.514) and Δh (ß = -0.427) in simple linear regression analysis. CONCLUSION: The AWE on HR-VWI was correlated with the PHASES and ELAPSS scores and the color. The stronger the AWE, the higher were the PHASES and ELAPSS scores and the more abnormal was the color. The AWE might indicate the degree of inflammation.

Usefulness of 3D High-resolution Vessel Wall MRI in Diffuse Nonaneurysmal SAH Patients.

PURPOSE: In 15-20% of patients with nontraumatic diffuse subarachnoid hemorrhage (SAH), the initial conventional angiography does not reveal a causative vascular abnormality, such as intracranial aneurysm. In this study, we evaluated clinical utility of 3D high-resolution vessel wall magnetic resonance imaging (HR-VWI) in patients with diffuse nonaneurysmal SAH. METHODS: A total of 17 patients with diffuse nonaneurysmal SAH were included in this retrospective study. We characterized demographics and HR-VWI findings and reviewed the clinical management and outcomes. RESULTS: Of the patients 14 (14/17; 82.4%,) showed abnormal findings on HR-VWI, including 5 with intracranial dissections (29.4%), 3 with blood blister-like aneurysm (17.6%), 1 with ruptured fusiform aneurysm (5.9%), and 5 with focal nodular wall enhancement without unclassified pathology (29.4%). Of these patients were treated with endovascular management. Most patients (16/17) had a favorable modified Rankin scale scores of 0-2 on discharge. CONCLUSION: The 3D HR-VWI revealed various hidden pathologies, such as intracranial arterial dissection, blood blister-like aneurysm, and fusiform aneurysm in patients with diffuse nonaneurysmal SAH. In addition, 3D HR-VWI had an impact on the management of SAH. The 3D HR-VWI can be a complementary diagnostic method for patients with diffuse nonaneurysmal SAH in a research or clinical setting.

Is Stent-Assisted Coil Embolization for the Treatment of Ruptured Blood Blister-Like Aneurysms of the Supraclinoid Internal Carotid Artery Effective? : An Analysis of Single Institutional Experience with Pooled Data.

OBJECTIVE: Given the high risk of rebleeding and recurrence of blood blister-like aneurysms (BBAs), we treated ruptured BBAs of the internal carotid artery (ICA) with stent-assisted coil embolization (SAC). This study aimed to evaluate the efficacy and safety of SACs. METHODS: We retrospectively reviewed clinical and radiological data from eight patients with ruptured BBAs of the supraclinoid ICA. The modified Rankin Scale (mRS) was used to assess clinical outcomes, while radiological outcomes were evaluated on angiographs. For a pooled analysis, data from literature reporting the outcomes of ruptured BBAs treated with SAC were collected and analyzed in conjunction with our data. RESULTS: In our cohort, the mean Raymond classification score was 1.57±0.53 immediately after initial endovascular treatment. There were no perioperative complications or rebleeding events during the follow-up period. The mean mRS score at patient discharge was 1.00±0.81 and improved to 0.28±0.48 by the last follow-up day. The recurrence rate was 25% with an asymptomatic presentation and successful treatment with multiple stent insertion. Pooled analysis of 76 cases of SAC revealed a complete occlusion rate immediately after treatment of 54.8%, rebleeding rate 7.94%, and recurrence rate 24.2%. Good clinical outcomes with mRS score 0-2 were observed in 89.9% by the last clinical follow-up. Total mortality rate was 7.7%. CONCLUSION: This treatment appears to not only minimize the hemodynamic burden on the fragile dome specific to this type of aneurysm, but also provides an opportunity for safe and effective treatment in recurrent cases.

Efficacy and Safety of Timely Urgent Superficial Temporal Artery-to-Middle Cerebral Artery Bypass Surgery in Patients with Acute Ischemic Stroke: A Single-Institutional Prospective Study and a Pooled Analysis.

BACKGROUND: Clinical outcome in patients with acute ischemic stroke (AIS) caused by large vessel occlusion (LVO) is not satisfactory if reperfusion treatment fails or is not tried. AIMS: We aimed to assess the efficacy and safety of urgent superficial temporal-to-middle cerebral artery (STA-MCA) bypass surgery in selected patients. METHODS: Patients who were diagnosed with LVO-induced AIS in the anterior circulation but had a failed intra-arterial thrombectomy (IAT) or were not tried due to IAT contraindications were prospectively enrolled. Timely urgent STA-MCA bypass surgery was performed if they showed perfusion-diffusion mismatch or symptom-diffusion mismatch in the acute phase of disease. Clinical and radiological data of these patients were assessed to demonstrate the safety and efficacy of urgent bypass procedures. A pooled analysis of published data on urgent bypass surgery in acute stroke patients was conducted and analyzed. RESULTS: In 18 patients who underwent timely bypass, the National Institutes of Health Stroke Scale (NIHSS) score improved from 12.11 ± 4.84 to 9.89 ± 6.52, 1 week after surgery. Three-month and long-term (9.72 ± 5.00 months) favorable outcomes (modified Rankin Scale [mRS] scores 0-2) were achieved in 50 and 75% of the patients, respectively. The pooled analysis (117 patients from 10 articles, including ours) identified favorable mRS scores in 71.79% patients at 3 months. A significant NIHSS score improvement from 11.51 ± 4.89 to 7.59 ± 5.50 was observed after surgery with significance. Major complications occurred in 3 patients (2.6%, 3/117) without mortality. CONCLUSIONS: Urgent STA-MCA bypass surgery can be regarded as a safe optional treatment to prevent cerebral infarct expansion and to improve clinical and radiological outcomes in highly selected patients.

Evaluation of red blood cell profiles in dogs with heartworm disease.

Recent studies have found that anemia and anisocytosis are precipitating factors for certain heart diseases in dogs. This study evaluated the prevalence and correlation of anemia and red blood cell distribution width (RDW) in dogs with heartworm disease (HWD). The study population consisted of 20 healthy control dogs and 86 dogs with HWD: 28 dogs with no clinical signs or pulmonary hypertension (Group 1), 42 dogs with mild clinical signs but no pulmonary hypertension (Group 2), and 16 dogs with severe clinical signs and pulmonary hypertension (Group 3). Along with echocardiographic interrogation of pulmonary hypertension, red blood cell (RBC) profiles were evaluated, including RDW. The total number of red blood cells (tRBCs), hematocrit (HCT), and hemoglobin (HGB) concentration was significantly lower in Group 3 dogs compared to control dogs (P < 0.05), while the RDW was significantly higher in Group 3 dogs than in control dogs (P < 0.05). The RDW was closely correlated to other RBC profiles and the presence of pulmonary hypertension (P < 0.05). The severity of tricuspid regurgitant gradient (TRG) was closely correlated with Hb and tRBC (P < 0.05), but not with the RDW and reticulocyte count. This study finding indicated that anemia and anisocytosis are common complications in dogs with severe clinical signs and pulmonary hypertension caused by heartworm disease (HWD). It would therefore be beneficial for clinicians to routinely check red blood cell (RBC) profiles, including RDW, in order to monitor the progression of heartworm disease in dogs.

Des études récentes ont montré que l'anémie et l'anisocytose sont des facteurs précipitants pour certaines conditions cardiaques chez les chiens. La présente étude a évalué la prévalence et la corrélation de l'anémie et de la distribution de la largeur des globules rouges (RDW) chez des chiens avec la maladie des vers du coeur (HWD). La population à l'étude consistait en 20 chiens témoins en santé et de 86 chiens avec HWD : 28 chiens sans signe clinique ou hypertension pulmonaire (Groupe 1), 42 chiens avec signes cliniques légers mais sans hypertension pulmonaire (Groupe 2) et 16 chiens avec signes cliniques sévères et hypertension pulmonaire (Groupe 3). En plus de l'interrogation échocardiographique de l'hypertension pulmonaire, les profils des globules rouges (RBC) furent évalués, incluant la RWD. Le nombre total de globules rouges (tRBCs), l'hématocrite (HCT) et la concentration en hémoglobine (Hb) étaient significativement plus bas chez les chiens du groupe 3 comparativement aux chiens témoins (P < 0,05) alors que la RWD était significativement plus élevée chez les chiens du Groupe 3 que chez les chiens témoins (P < 0,05). La RWD était étroitement corrélée à d'autres profiles de RBC et à la présence d'hypertension pulmonaire (P < 0,05). La sévérité du gradient de régurgitation de la tricuspide (TRG) était étroitement corrélée avec Hb et tRBC (P < 0,05), mais pas avec RWD et le dénombrement de réticulocytes. Les trouvailles de cette étude indiquent que l'anémie et l'anisocytose sont des complications fréquentes chez les chiens avec des signes cliniques sévères et de l'hypertension pulmonaire causés par HWD. Il serait donc bénéfique pour les cliniciens de vérifier de routine les profiles de RBC, incluant RWD, afin de suivre la progression de la maladie des vers du coeur chez les chiens.(Traduit par Docteur Serge Messier).

Thyroid isthmus agenesis and its clinical significance in a large-scale multidetector CT-based study.

OBJECTIVE: The purpose of this study was to estimate the incidence and clinical significance of thyroid isthmus agenesis based on multi-detector CT imaging in a large-scale study. METHODS: Data from 1601 patients who underwent neck multi-detector CT at our institution from January 2015 to March 2016 were included in this retrospective study. The morphology of each patient's thyroid gland was evaluated. We classified thyroid isthmus agenesis into two subgroups according to the thickness of the medial margin: clear-cut type (>4 mm) or tapering-edge type (≤4 mm). Associated thyroid pathologies were also evaluated. RESULTS: Thyroid isthmus agenesis was present in 69 patients (41 males, 28 females), and its incidence was 4.77%. Eleven patients (0.76%) had the clear-cut type and 58 patients (4.01%) had the tapering-edge type. Papillary thyroid carcinoma was diagnosed in 4 patients (5.7% of isthmus agenesis patients). A total of 7 patients underwent thyroid function testing during the course of this study; 1 of these patients presented with borderline hyperthyroidism, and the remaining 6 were in a euthyroid state. The clear-cut type showed a statistically significant narrow gap and a high incidence of pyramidal lobes compared to the tapering-edge type. CONCLUSION: Thyroid isthmus agenesis is not a rare developmental anomaly of the thyroid gland on multi-detector CT. Based on the metastatic pathophysiology of differentiated thyroid cancer, more extended indications for lobectomy are expected in differentiated thyroid cancer patients with thyroid isthmus agenesis.

Rathke Cleft Cysts with Apoplexy-Like Symptoms: Clinicoradiologic Comparisons with Pituitary Adenomas with Apoplexy.

BACKGROUND: Rathke cleft cyst (RCC) can cause acute symptoms mimicking pituitary adenoma (PA) apoplexy. We evaluated the clinicoradiologic features for distinguishing RCC from PA apoplexy. METHODS: We retrospectively evaluated 22 patients with RCC and 24 patients with PA with apoplexy-like symptoms who underwent surgery via a transsphenoidal approach between November 1999 and December 2016. We compared the clinical data and magnetic resonance (MR) images between the 2 groups. RESULTS: The RCC group was younger and had smaller tumors compared with the PA group (P = 0.02 and 0.001, respectively). The incidences of visual deficits and cranial nerve palsy were lower in the RCCs than in the PAs (P ≤ 0.02 for all). MR images showed more frequent intracystic nodules in the RCCs (P < 0.001), whereas nodular enhancement and lateral deviation of the pituitary stalk were more commonly seen in the PAs (P ≤ 0.003 for both). However, the presence of endocrine dysfunction or decreased consciousness, and the recurrence ratio, were not significantly different between the groups (P ≥ 0.48 for all). In the multivariable logistic regression analysis, patients without nodular enhancement had a 15.84-fold greater risk of RCC than did those with nodular enhancement (P = 0.031). The probability of RCC decreased 0.59-fold with each 1-cm3 increase in tumor volume. CONCLUSIONS: RCC with apoplexy-like symptoms has different clinicoradiologic features compared with PA apoplexy. Patients with RCC present with milder ocular symptoms and smaller tumor volumes compared with those with PA apoplexy. The absence of nodular enhancement on MR images could suggest RCC.

Cortical and subcortical gray matter alterations in first-episode drug-naïve adolescents with major depressive disorder.

Major depressive disorder is a major mental disorder affecting adolescents. Cortical thickness provides a sensitive measure of age-associated changes. Previous studies using cortical thickness analysis reported inconsistent results on brain structural changes in adolescent major depressive disorder. The neuroanatomical substrates of major depressive disorder in adolescents are not fully understood. We aimed to compare the anatomical structures of the brain in first-onset drug-naïve adolescents with major depressive disorder to normal controls. Twenty-seven first-episode drug-naïve adolescents with major depressive disorder and an equal number of age-matched control subjects were scanned on a 3T MRI scanner. Comparisons between those two groups were performed using surface-based morphometry analysis for cortical thickness and volumetric analysis of subcortical gray matter. The correlations between morphometric indexes and clinical measures (Hamilton depression rating scale score or children's depression inventory score) were also calculated. We found that the cortical area is thinner in major depressive disorder patients than in controls, specifically in the left occipital area (precuneus and cuneus, cluster-level family-wise corrected P < 0.05). The hippocampus volume was also smaller in major depressive disorder patients than in the control group. No significant correlations were found between morphometric indexes (average cortical thickness extracted from the left precuneus cluster and hippocampal volume) and clinical measures. The left occipital cortical regions may have a role in the pathophysiology of adolescent major depressive disorder, and the involvement of the hippocampus is important for pathogenic changes even in the early stages of major depressive disorder.

Comparison of stent-assisted and no-stent coil embolization for safety and effectiveness in the treatment of ruptured intracranial aneurysms.

OBJECTIVE: The safety of the stent-assisted coil embolization (SAC) technique for acutely ruptured aneurysms has not been established yet. SAC is believed to be associated with a high risk of thromboembolic and hemorrhagic complications in acute subarachnoid hemorrhage (SAH). The aim of this study was to evaluate the safety and efficacy of the SAC technique in the setting of acutely ruptured aneurysm. METHODS: A total of 102 patients who received endovascular treatment for acute SAH between January 2011 and December 2017 were enrolled. The SAC technique was performed in 38 of these patients, whereas the no-stent coil embolization (NSC) technique was performed in 64. The safety and efficacy of the SAC technique in acute SAH was evaluated as compared with the NSC technique by retrospective analysis of radiological and clinical outcomes. RESULTS: There were no significant differences in clinical or angiographic outcomes between the SAC and NSC techniques in patients with acute SAH. The rate of ventriculostomy-related hemorrhagic complications was higher in the SAC group than that in the NSC group (63.6% vs 12.5%; OR 12.25, 95% CI 1.78-83.94, p = 0.01). However, all these complications were asymptomatic and so small that they were only able to be diagnosed with imaging. CONCLUSIONS: Ruptured wide-necked aneurysms could be effectively and safely treated with the SAC technique, which showed clinical and angiographic outcomes similar to those of the NSC technique. Hence, the SAC technique with dual-antiplatelet drugs may be a viable option even in acute SAH.