Kazuhisa Yoshifuji

Dotlike Hemosiderin Spots Are Associated With Past Hemorrhagic Strokes in Patients With Lacunar Infarcts

Background and Purpose. Dotlike hemosiderin spots ongradient‐echo T2*‐weighted magnetic resonance imaging of the brain have been histologically diagnosed as old microbleeds associated with small vessel disease (SVD). The authors hypothesize that the presence of many dotHSs may be correlated with the fragility of small vessels and the recurrence of SVD, including lacunar infarction and deep intracerebral hemorrhage (ICH). Methods. To investigate how dotHSs are related to past history of SVD, the number of subcortical or deep dotHSs was investigated in 146 patients with lacunar infarctions (95men, 51 women, age 38 to 90 [66.6 ± 9.4] years). They were divided into 2 subgroups according to history of deep ICHs or lacunar infarctions. The odds ratio (OR) for past history was estimated from logistic regression analyses with the number of subcortical or deep dotHSs as well as other factors. Results. Of 146 patients with lacunar infarctions, 11 had past symptomatic ICHs and 19 had past symptomatic lacunar infarctions. An elevated rate of history of ICH was found for lacunar infarction patients with many deep dotHSs (≥3; OR, 9.1; 95% confidence interval, 1.6–51, P= .015). However, history of lacunar infarction was not significantly associated with the number of subcortical or deep dotHSs. Conclusions. Our findings suggest that many deep dotHSs on T2*‐weighted magnetic resonance imaging may be correlated with deep ICH—lacunar infarction type of SVD recurrence but not lacunar infarction—lacunar infarction type.

Nascent deep microbleeds and stroke recurrences.

BACKGROUND Cerebral microbleeds (MBs) on gradient echo T2*-weighted magnetic resonance imaging (MRI) scans are associated with the severity of cerebral microangiopathies. This study investigated the contributions of nascent deep MBs to stroke recurrence. METHODS We prospectively analyzed nascent deep MBs in patients admitted to our hospital who were treated for index strokes between April 2004 and November 2009. The number of nascent deep MBs was counted on T2*-weighted MRI scans around 1 year after the index strokes, and compared to previous MRIs on admission. Stroke recurrence-free rate curves were generated using the Kaplan-Meier method using the log-rank test. The odds ratio for nascent deep MBs was derived using a multivariate logistic regression model that was based on recurrent strokes and other risk factors. RESULTS We evaluated the MRIs (interval between MRIs 14.6 ± 5.9 months) of 508 patients (207 women; 68.9 ± 11.5 years), with a follow-up period of 44.1 ± 15.4 months. Repeated T2*-weighted MRI scans revealed 256 nascent deep MBs in 116 of 508 patients. The incidence of deep intracerebral hemorrhage was significantly greater in patients with nascent deep MBs than those without (2.0% vs 0.4% per year, respectively; P < .0001). Multivariate analyses revealed that the rate of nascent deep MBs was significantly elevated in patients whose stroke recurrences took the form of deep intracerebral hemorrhages (odds ratio 5.41; P = .007), when adjusted for hypertension, preexisting MBs, and other risk factors. CONCLUSIONS Our findings suggested that nascent deep MBs might be associated with stroke recurrence, in particular with deep intracerebral hemorrhage.

Antithrombotic Drug Uses and Deep Intracerebral Hemorrhages in Stroke Patients With Deep Cerebral Microbleeds

BACKGROUND It has been suggested that antiplatelet or anticoagulant drugs elevate the rate of intracerebral hemorrhage (ICH) in patients with cerebral microbleeds (MBs). To investigate the mechanism by which antiplatelet drugs or warfarin may contribute to deep ICH occurrences in patients with deep MBs, we prospectively analyzed deep ICH occurrences in 807 consecutive patients (351 females and 456 males; mean age ± standard deviation 69.8 ± 12.0 years) who were admitted to our hospital with strokes. METHODS Occurrence-free rate curves were generated using the Kaplan-Meier method; deep ICH occurrence-free rates were compared using the log-rank test. The follow-up period was 0.5 to 71 months (mean ± standard deviation 31.6 ± 22.2 months). RESULTS In patients with deep MBs, the rates (1.0%/year; 6 ICHs in 180 patients) of deep ICH occurrence associated with antiplatelet drugs were not significantly greater than that without the drugs (1.0%/year; 6 ICHs in 167 patients; P = .977). The incidence of deep ICHs associated with warfarin use was not significantly greater than that without warfarin use. CONCLUSIONS Multivariate analysis revealed that the use of antiplatelet drugs or warfarin did not significantly influence the occurrence of deep ICH in patients with deep MBs. Antiplatelet drugs or warfarin did not significantly elevate the rate of deep ICHs in stroke patients with pre-existing deep MBs.

Interstitial spinal-cord oedema in syringomyelia associated with Chiari type 1 malformations

Object: The pathophysiology of syringomyelia in Chiari type 1 malformations has not been clarified. Oedema-like spinal-cord swelling was recently reported in several pathological conditions, including Chiari type 1 malformations as a pre-syrinx state. However, the role of the pre-syrinx state in the development of syringomyelia is unknown. The purpose of this study is to investigate the parenchymal changes of the spinal cord in syringomyelia associated with Chiari type 1 malformations. Methods: Pre- and postoperative MRI findings in 14 patients who underwent foramen magnum decompression in our institute were reviewed. The analysis was focused on differences in visualisation of the syrinx between T1- and T2-weighted images and abnormal parenchymal signal changes. There were 6 men and 8 women, aged from 6 to 79 years. No patients showed hydrocephalus. Results: Twelve patients had large and expansive syrinx, whereas 2 patients showed small syrinx confined to the centre of the spinal cord. T2-weighted images displayed significantly larger intramedullary abnormal signal areas. Nine patients showed parenchymal hyperintensity areas around the enlarged central canal or base of the posterior white columns adjacent to the syringomyelic cavity. Such parenchymal hyperintensity areas markedly diminished with reduction of the syrinx after surgery and were considered to be interstitial oedema. Conclusions: From this study, the interstitial oedema of the spinal cord commonly accompanies syringomyelia with Chiari type 1 malformations. Accumulation of the extracellular fluid due to disturbed absorption mechanisms may play an important role in the pathophysiology of syringomyelia associated with Chiari type 1 malformations.

Nascent Lobar Microbleeds and Stroke Recurrences

BACKGROUND Lobar microbleeds (MBs) are occasionally visible on gradient-echo T2*-weighted (T2*-w) magnetic resonance imagings (MRIs) in patients with deep intracerebral hemorrhages (ICHs). This study investigated the contribution of nascent lobar MBs to occurrences of deep ICHs. METHODS We prospectively analyzed nascent lobar MBs in patients admitted to our hospital who were treated with index strokes between April 2004 and November 2009. Numbers of nascent lobar MBs were counted on T2*-w MRI scans around 1 year after index strokes and compared with previous MRIs on admission. Deep ICH occurrence-free rate curves were generated by the Kaplan-Meier method using the log-rank test. The odds ratio (OR) for deep ICH occurrence was derived from a multivariate logistic regression model using nascent lobar MBs and risk factors. RESULTS We investigated MRIs (interscan interval: 14.6 ± 5.9 months) of 508 patients (207 women, 68.9 ± 11.5 years), with a follow-up period of 44.1 ± 15.4 months. Repeated T2*-w MRIs demonstrated 157 nascent lobar MBs in 62 of 508 patients. The occurrence rate of deep ICHs (1.9% per year) was significantly higher in patients with nascent lobar MBs than in those without (.5% per year, P = .012). Multivariate analyses revealed that the rate of nascent lobar MBs was significantly elevated in patients with deep ICH-type stroke recurrences (OR: 3.85, P = .020), adjusted by the presence of hypertension, diabetes mellitus, use of antithrombotic drugs, severity of white matter lesions, age, and gender. CONCLUSIONS Though a cohort study limited the power of analyses, our findings suggested that lobar MBs might be associated with deep ICH.

Radiological findings and clinical course of conus lipoma: implications for surgical treatment.

OBJECTIVEA significant variety in morphology of conus lipomas may underlie differences in clinical presentation of the patients and controversy in surgical management. We retrospectively studied 58 patients with conus lipomas at our institutions. The purpose of this study was to infer the clinical course from the radiological findings and to provide information for decision-making in planning for surgical treatment. METHODSThe patients underwent untethering surgery between 1984 and 2005. There were 35 transitional and 23 dorsal lipomas. The age at surgery ranged from 1 month to 50 years (median, 4 yr). Preoperative clinical history, radiological findings, and postoperative results were analyzed. RESULTSFifteen patients were asymptomatic, and 43 patients were symptomatic preoperatively. Twenty-one patients presented with motor deficits of the lower extremities. In seven patients, motor deficits appeared early, before 1 year of age. Massive lipomas compressing the cord or herniation of the spinal cord into the subcutaneous tissue were characteristic findings of such early deterioration. Motor deficits were present in 73% of patients with lipomas extending to the lumbar level, whereas 88% of patients with lipomas confined to the sacral level had only urinary deficits. During a mean postoperative follow-up period of 7.9 years, 4 (27%) of the 15 asymptomatic patients developed urinary and/or motor deficits, and 12 (28%) of the 43 symptomatic patients showed further neurological deterioration. CONCLUSIONThis study demonstrates that the location and morphology of conus lipomas influence the neurological presentation of the patients. Early prophylactic surgery is a reasonable treatment option if early deterioration is predicted by imaging studies.

Dot‐Like Hemosiderin Deposition on T2*‐Weighted MR Imaging Associated with Nonhypertensive Intracerebral Hemorrhage

Background and Purpose. Microangiopathy, a disorder often related to hypertension, is an important cause of deep intracerebral hematoma (ICH). The microangiopathy is associated with dot‐like low‐intensity spots (a dot‐like hemosiderin spot: dotHS) on gradient‐echo T2*‐weighted MR images that have been histologically diagnosed as old microbleeds. The locations of dotHS are consistent with deep ICH. Methods. To investigate how dotHS or other risk factors contribute to nonhypertensive deep ICH, the number and location of dotHSs, as well as other risk factors were examined in 213 deep ICH patients (106 males, 107 females, age: 37‐94 (65.8 ± 11.2) years) consecutively admitted to Hakodate Municipal Hospital. Patients were divided into two subgroups according to the presence or absence of hypertension. DotHSs were also divided into deep and subcortical dotHS and investigated independently. Odds ratios (ORs) were estimated from logistic regression analyses. Furthermore, nonhypertensive ICH patients were compared with nonhypertensive healthy volunteers matched for age and sex. Results. No risk factors were identified in the 31 nonhypertensive deep ICH patients that differed from those found in the 182 hypertensive deep ICH patients. Deep dotHS ≥ 1 (OR: 25.5; 95% CI: 4.76‐137; P= .0002), subcortical dotHS ≥ 1 (OR: 9.0; 95% CI: 1.79‐44.9; P= .046), diabetes mellitus (OR: 9.0; 95% CI: 1.53‐52.3; P= .015), and smoking (OR, 9.6; 95% CI; 1.8‐49.8, P= .007) significantly elevated the risk of nonhypertensive ICH, compared to the healthy volunteers. Conclusions. Our findings suggest that deep and subcortical dotHSs may be risk factors for the development of non‐hypertensive deep ICH.

Pathophysiological consideration of medullary streaks on FLAIR imaging in pediatric moyamoya disease

OBJECTIVE Medullary streaks detected on fluid-attenuated inversion recovery (FLAIR) imaging have been considered to be reflected ischemic regions in pediatric moyamoya disease. The purpose of this study was to evaluate these medullary streaks both clinically and radiologically and to discuss associated pathophysiological concerns. METHODS The authors retrospectively reviewed data from 14 consecutive pediatric patients with moyamoya disease treated between April 2009 and June 2016. Clinical and radiological features and postoperative imaging changes were analyzed. In 4 patients, hyperintense medullary streaks on FLAIR imaging (HMSF) at the level of the centrum semiovale were detected. RESULTS The HMSF were coincident with hyperintense medullary streaks on a T2-weighted image, though they were not completely coincident with the vasculature on either a T2*-weighted image or contrast-enhanced CT. Analysis revealed significantly higher values in terms of MR angiography scores, number of flow voids of the basal ganglia, and the presence of the medullary artery in the group with HMSF than in those without. In contrast, the presence of white matter damage was significantly less frequent in the HMSF group. All HMSF disappeared after surgery, and the mean apparent diffusion coefficient at the same level was significantly reduced postoperatively. CONCLUSIONS Although HMSF should be associated with collateral circulation in moyamoya disease, other factors may be involved, including stagnated cerebrospinal fluid or vasogenic edema that is relevant to the impaired state of the white matter. Findings in this study provide insight into the pathophysiological basis of the perivascular space in moyamoya disease.

Infant Motor Development Recovery after Surgery of Post TraumaticEpilepsy (PTE) - Meaningful Change of Fractional Anisotropy (FA) of MRIDiffusion Tensor Imaging (DTI) in a Case of Growing Skull Fracture

Epileptic seizure in pediatric patients affects neurodevelopment, and surgical treatment of intractable epilepsy improved comorbidities, but the mechanism is not fully uncovered yet. By measurement of MRI-DTI Fractional Anisotropy (FA) of posterior limb of internal capsule (PIC) of infants, we presented its change by seizure propagation and control in a case of an infant post traumatic epilepsy (PTE) caused by growing skull fracture. Her motor developmental delay and hemiparesis with non-convulsive status epilepticus (NCSE) started 2 months after injury, recovered after surgical repair and seizure control. FA of PIC was lower than normal (0.29 ipsilateral, 0.37 contralateral) had increased to normal range in one week after surgical treatment and seizure control (0.62, 0.66). Comparing with normal time course of FA of motor tract of infant, this dynamic change of FA indicated the effect of seizure control after surgical treatment. As measurement of other brain lesion also showed increased FA in both ipsilateral and contralateral deep white matter, indicated the effect of NCSE for wide network of brain, and influenced infant neuronal development. These result indicated one mechanism why NCSE affected motor developmental delay and surgical intervention for regional infant intractable epilepsy prevented further developmental delay. By handy method of measuring FA of motor tract, we had one possibility to predict motor tract injury in infancy. We also reviewed and discussed about the mechanism of FA increase and decrease in early infancy and how PTE caused FA change.

Subcortical heterotopia appearing as huge midline mass in the newborn brain.

IntroductionWe report the case of a 2-year-old boy who showed a huge midline mass in the brain at prenatal assessment.Case reportAfter birth, magnetic resonance imaging (MRI) revealed a conglomerate mass with an infolded microgyrus at the midline, which was suspected as a midline brain-in-brain malformation. MRI also showed incomplete cleavage of his frontal cortex and thalamus, consistent with lobar holoprosencephaly. The patient underwent an incisional biopsy of the mass on the second day of life. The mass consisted of normal central nervous tissue with gray and white matter, representing a heterotopic brain. The malformation was considered to be a subcortical heterotopia. With maturity, focal signal changes and decreased cerebral perfusion became clear on brain imaging, suggesting secondary glial degeneration. Coincident with these MRI abnormalities, the child developed psychomotor retardation and severe epilepsy focused on the side of the intracranial mass.