[A Case of the Internal Carotid Artery Occlusion Immediately After Intravenous Recombinant Tissue Plasminogen Activator Treatment for Contralateral Middle Cerebral Artery Occlusion].

Early recurrent ischemic stroke (ERIS), as well as symptomatic intracranial hemorrhage (SICH) and progressive stroke (PS), causes early neurological deterioration. Here we report a case of a patient with right internal carotid artery (ICA) occlusion immediately after intravenous recombinant tissue plasminogen activator (rt-PA) treatment for left middle cerebral artery (MCA) occlusion. A 79-year-old woman with drowsiness, aphasia and right hemiparesis was brought to our hospital. MRI showed acute infarction in the left internal capsule and occlusion of the left middle cerebral artery. rt-PA was administered intravenously to the patient 2 hours after the onset of the event. Her consciousness disturbance and aphasia improved, but the right hemiparesis did not. We performed emergent endovascular thrombectomy, but the right ICA (cervical portion) was occluded during the surgery. Finally, the endovascular thrombectomy achieved the recanalization of the left MCA and right ICA. When performing intravenous thrombolysis, we should beware the possibility of re-occlusion and prepare for interventional treatment.

Intracranial vessel wall lesions in patients with systematic lupus erythematosus.

BACKGROUND: Systemic lupus erythematosus (SLE) is related to vasculitis, which causes brain infarctions; however, the pathology of large cerebral vessels has not been fully established. PURPOSE: To demonstrate the prevalence of vessel wall lesions (VWLs) in SLE patients using 3D vessel wall imaging and to assess the relationship between VWLs and brain infarctions. STUDY TYPE: Retrospective. SUBJECTS: Sixty SLE patients and 50 healthy subjects (HS). FIELD STRENGTH/SEQUENCE: Each subject underwent 3T MRI, which included 3D FSE PDWI (CUBE). ASSESSMENT: For each of the 33 segments of the intracranial artery (internal carotid artery ∼ M3 segment of middle cerebral artery [MCA]), the VWLs were scored as either positive or negative, and the VWL score was calculated as the sum of the segments with VWLs. We also evaluated brain lesions on conventional MRI. STATISTICAL TESTS: We used logistic regression analyses to determine the clinical (serological test and cardiovascular risk factors) and imaging characteristics associated with infarctions in SLE patients. RESULTS: For the peripheral vessels such as MCA, VWLs were more common for SLE patients than for HS (43.3% versus 16.7% in M1 segment, 60.4% versus 16.7% in M2 segment, both P < 0.01). There were 21 infarctions in 13 patients (21.7%), and the median VWL score was larger in the patients with infarctions than in those without (13 versus 6, P < 0.01). Multivariate logistic regression analyses revealed a high VWL score ( ≥ 9) to be the only factor independently associated with the presence of infarctions (odds ratio: 10.1, 95% confidence interval: 1.01-101; P < 0.049). DATA CONCLUSION: We demonstrated a substantially high prevalence of VWLs among SLE patients, which were associated with brain infarctions. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:1237-1246.

Identification of Heschl's gyrus on phase difference enhanced imaging.

Background The white matter in the Heschl's gyrus (HG-WM) may appear differently to the other gyri on phase difference enhanced imaging (PADRE), which can enhance the myelin density. Purpose To evaluate the signal intensity (SI) of HG-WM using the PADRE technique and to compare the images with susceptibility-weighted imaging (SWI)-like images. Material and Methods The participants included 19 normal controls (38 HGs; mean age, 60.1 years; age range, 28-80 years). Coronal PADRE and SWI-like images were acquired using a 3T magnetic resonance (MR) system. The SI of the HG-WM was classified into three grades based on a comparison with the SI of the superior temporal gyrus: Grade 1, isointense; Grade 2, slightly hypointense, and Grade 3, markedly hypointense. Results In the assessment of the SI of the HG-WM, the HG-WM appeared hypointense in all 38 sites of the 19 participants; the hypointensity corresponded to Grade 2 in 13 (34%) images and Grade 3 in 25 (66%) images. On the other hand, the HG-WM was classified as Grade 1 (isointense) in all of the SWI-like images. Conclusion The HG-WM appears hypointense on PADRE, which probably reflects the higher myelin content. PADRE may be useful for identifying the HG through the assessment of the SI of the HG-WM.

Quantitative susceptibility mapping in patients with systemic lupus erythematosus: detection of abnormalities in normal-appearing basal ganglia.

OBJECTIVES: To evaluate whether quantitative susceptibility mapping (QSM) can be employed to detect abnormalities within normal-appearing basal ganglia on conventional MRI in patients with neuropsychiatric systemic lupus erythematosus (NPSLE). METHODS: For 33 SLE patients (13 NPSLE and 20 non-NPSLE patients) and 23 age/sex-matched controls, two radiologists independently measured the mean QSM and R2* values in various brain structures that appeared to be normal on conventional MR images. These values in each brain structure were compared among the two SLE groups and controls. RESULTS: Regarding the putamen, the NPSLE patients showed significantly higher QSM values than the non-NPSLE patients and controls (p < 0.05). For the lateral globus pallidus, both SLE groups showed significantly higher QSM values than the controls (p < 0.05). The R2* values were not significantly different between both SLE groups. The NPSLE patients showed a significant correlation between the mean QSM values in putamen and the disease duration (r = 0.63, p < 0.05). For the interobserver agreement, the QSM value was superior to the R2* value (0.690 vs. 0.446, Kendall W value). CONCLUSIONS: QSM can be used to identify increased susceptibility of the basal ganglia appearing to be normal on conventional MR images in NPSLE patients. KEY POINTS: • QSM values in the putamen are significantly higher in NPSLE than non-NPSLE. • NPSLE patients show correlation between QSM values in the putamen and disease duration. • QSM is more sensitive than R2* mapping for detecting subtle changes.

Zebra sign of precentral gyri in amyotrophic lateral sclerosis: A novel finding using phase difference enhanced (PADRE) imaging-initial results.

OBJECTIVE: We compared the precentral gyri (PG) on the PADRE of patients with amyotrophic lateral sclerosis (ALS) and healthy subjects (HSs) in order to determine whether it is possible to discriminate between ALS patients and HSs on an individual basis. METHODS: First, two radiologists reviewed the appearance of the normal PG and that of ALS patients on PADRE in a non-blinded manner, and deviations from the appearance of the normal PG were recorded. Next, based on the presence of PG abnormalities on PADRE, we performed an observer performance study using 16 ALS patients and 16 HSs. RESULTS: The radiologists were able to consensually define the PG as abnormal on PADRE when a low-signal-intensity layer was observed in the gray matter of the PG; a three- or four-layer organization (zebra sign) was characterized by the low-signal-intensity layer. The observer performance study demonstrated that the sensitivity, specificity, and accuracy of PG abnormalities on PADRE for discriminating ALS patients from HSs were 94 %, 94 %, and 94 %, respectively, for reviewers 1 and 2. CONCLUSIONS: It was possible to discriminate between ALS patients and HSs based on the presence of PG abnormalities on PADRE, which may reflect upper motor neuron impairment in ALS. KEY POINTS: • PADRE reveals low-signal-intensity layer in the PG of ALS • By PADRE findings on PG, we can discriminate ALS from HSs • PADRE may be a useful method for detecting UMN impairment in ALS.

Internal structures of the globus pallidus in patients with Parkinson's disease: evaluation with quantitative susceptibility mapping (QSM).

OBJECTIVES: The aim of this study was to assess the susceptibility change in medial and lateral globus pallidus (GPm and GPl) related to age separately, using quantitative susceptibility mapping (QSM) and to determine whether QSM can depict GPm in Parkinson's disease (PD) patients. METHODS: QSM was performed in 19 PD patients and in 41 normal control (NC) subjects. First, we quantitatively analysed age-related changes in QSM value in NC for GPl and GPm by a manual region of interest (ROI) technique. Then, in PD patients and age-matched NC subjects, we evaluated the depiction of GPm on QSM images qualitatively. RESULTS: In NC, the QSM value within GPl significantly increased gradually with age (r = 0.32, p = 0.04), whereas it did not change with age in GPm. The average QSM value was significantly larger for GPl than for GPm (205 vs 191, p < 0.05). In both PD patients and age-matched NC, the depiction of GPm on QSM images was good in most cases (87 %, 33 of 38 sides in PD patients) mainly because of the differences in susceptibility between GPm and GPl. CONCLUSIONS: The QSM value in GPl increases gradually with age, which allows for the identification of GPm in elderly PD subjects.

[Construction of System for Support of Multifacility IVR Dose Analysis and Research].

Although measurement and management of angiographic entrance skin dose (ESD) are deemed extremely important, accurate determination of maximum ESD and its location is generally difficult because of the dependence on therapeutic technique and position. Following our development of body-mounted gear bearing radiophotoluminescence glass dosimeter (RPLD) arrays for direct measurement of ESD in cranial and cardiovascular angiography and interventional radiology (IVR), our focus next turned to the limited number of facilities equipped to read RPLD outputs and the need for methods to effectively provide feedback to clinical facilities. As described here, we first constructed an RPLD reading facility capable of sending and receiving RPLDs by post, offering the potential to enable utilization of the developed gear at all hospitals in Japan that perform angiography and IVR. We next developed specialized web-based system to generate dose maps from RPLD dose data, thereby enabling any facility to perform trial system analysis, evaluation, and implementation; and investigated the results and related problems.

Usefulness of Olfactory Bulb Measurement in 3D-FIESTA in Differentiating Parkinson Disease from Atypical Parkinsonism.

BACKGROUND AND PURPOSE: Parkinson disease is a prevalent disease, with olfactory dysfunction recognized as an early nonmotor manifestation. It is sometimes difficult to differentiate Parkinson disease from atypical parkinsonism using conventional MR imaging and motor symptoms. It is also known that olfactory loss occurs to a lesser extent or is absent in atypical parkinsonism. To the best of our knowledge, no study has examined olfactory bulb changes to differentiate Parkinson disease from atypical parkinsonism, even in an early diagnosis, and its association with conventional MR imaging findings. Hence, we aimed to assess the utility of olfactory bulb measurements in differentiating Parkinson disease from atypical parkinsonism even in the early stage. MATERIALS AND METHODS: In this retrospective study, we enrolled 108 patients with Parkinson disease, 13 with corticobasal syndrome, 15 with multiple system atrophy, and 17 with progressive supranuclear palsy who developed parkinsonism. Thirty-nine age-matched healthy subjects served as controls. All subjects underwent conventional MR imaging and 3D FIESTA for olfactory bulb measurements using manual ROI quantification of the cross-sectional olfactory bulb area using the coronal plane. Bilateral olfactory bulb measurements were averaged. For group comparisons, we used the Welch t test, and we assessed diagnostic accuracy using receiver operating characteristic analysis. RESULTS: Patients with Parkinson disease had a mean olfactory bulb area of 4.2 (SD, 1.0 mm2), significantly smaller than in age-matched healthy subjects (6.6 [SD, 1.7 mm2], P < .001), and those with corticobasal syndrome (5.4 [SD, 1.2 mm2], P < .001), multiple system atrophy (6.5 [SD, 1.2 mm2], P < .001), and progressive supranuclear palsy (5.4 [SD, 1.2 mm2], P < .001). The receiver operating characteristic analysis for the olfactory bulb area measurements showed good diagnostic performance in differentiating Parkinson disease from atypical parkinsonism, with an area under the curve of 0.87, an optimal cutoff value of 5.1 mm2, and a false-positive rate of 18%. When we compared within 2 years of symptom onset, the olfactory bulb in Parkinson disease (4.2 [SD, 1.1 mm2]) remained significantly smaller than in atypical parkinsonism (versus corticobasal syndrome (6.1 [SD, 0.7 mm2]), P < .001; multiple system atrophy (6.3 [SD, 1.4 mm2]), P < .001; and progressive supranuclear palsy (5.2 [1.3 mm2], P = .003, respectively). CONCLUSIONS: 3D FIESTA-based olfactory bulb measurement holds promise for distinguishing Parkinson disease from atypical parkinsonism, especially in the early stage.

D-dimer level elevation can aid in detection of asymptomatic COVID-19 presenting with acute cerebral infarction.

Coronavirus disease 2019 (COVID-19) mainly manifests as a respiratory syndrome, besides causing other complications. Severe COVID-19 may also present with coagulopathy, leading to venous thrombosis and cerebral infarction. Generally, acute stroke is a secondary complication in patients displaying respiratory syndromes. Here, we present a case of acute stroke in an 84-year-old female patient who did not manifest any respiratory symptoms. The patient had no cough or fever before the stroke onset; nevertheless, COVID-19 PCR test was positive. The patient also had markedly elevated serum D-dimer levels. Our findings suggest that coagulopathy can occur even in a patient with asymptomatic COVID-19 infection, and to our knowledge, this is the first report of such a case. We concluded that elevated D-dimer levels can serve as an additional COVID-19 screening tool in stroke patients.

Correction to: The usefulness of full-iterative reconstruction algorithm for the visualization of cystic artery on CT angiography.

The authors wish to replace the Table 1.

The usefulness of full-iterative reconstruction algorithm for the visualization of cystic artery on CT angiography.

PURPOSE: To evaluate the potential of full-iterative reconstruction (IR) for improving image quality of the cystic artery on CT angiography and to assess observer performance. METHODS: Thirty patients who underwent both liver dynamic CT and conventional angiography were included in this retrospective study. All CT data were reconstructed through filtered back projection (FBP), adaptive iterative dose reduction 3D (AIDR3D), and forward-projected, model-based, iterative reconstruction solution (FIRST), respectively. In objective study, we analyzed mean ΔCT numbers (the difference between the HU peak of the vessel and the background) and full-width at tenth-maximum (FWTM) of three parts of the cystic artery by profile curve method comparing the three reconstructions. Subjectively, visualization was evaluated using a four-point scale performed by two blinded observers. ANOVA was used for statistical analysis. RESULTS: In all parts of the cystic artery, the mean ΔCT number of FIRST was shown to be significantly better than that of FBP and AIDR3D (p < 0.05). FWTM in FIRST was the smallest in all of the vessels. The mean visualization score was significantly better with FIRST than with other CT reconstructions (p < 0.05). CONCLUSIONS: The FIRST algorithm led to improved CTA visualization of the cystic artery.

Internal Structures of the Globus Pallidus in Patients with Parkinson's Disease: Evaluation with Phase Difference-enhanced Imaging.

PURPOSE: The medial medullary lamina (MML) separates the medial globus pallidus (GPm) from the lateral. The aim of this study was to assess the changes in appearance of MML related to age using the phase difference-enhanced (PADRE) imaging and to determine whether PADRE can depict the MML in the patients with Parkinson's disease (PD). MATERIALS AND METHODS: We enrolled 20 patients with PD and 50 normal control subjects (NC). First, for the visualization of the MML in the NC, we compared the PADRE, susceptibility-weighted imaging (SWI)-like images and T2 weighted imaging (WI) by using multiple comparison. The grading methods are as follows: grade 1; MML was not delineated, grade 2; less than half of MML was delineated, grade 3; more than half of MML was delineated and grade 4; whole MML was clearly delineated. We determined grade 3 and 4 as good depiction, delineating the GPm. Then, we evaluated patients with PD using the same method. RESULTS: In NC, the delineation of MML was good in 84% of cases on PADRE, but only 34% of cases showed a good depiction on SWI-like images (average grading score 3.31 vs 2.11, P < 0.05). No MML was delineated in all cases on T2 WI. Although younger subjects tended to show whole MML clearly, a part of MML tends to be obscured with age on PADRE. In patients with PD the depiction of MML on PADRE was also good in 90% of cases. CONCLUSION: The PADRE technique facilitates the depiction of the MML within globus pallidus (GP) on a broad range of age NC and patients with PD and it is superior to SWI-like images and T2 WI.

Juxtacortical Lesions in Multiple Sclerosis: Assessment of Gray Matter Involvement Using Phase Difference-enhanced Imaging (PADRE).

PURPOSE: In multiple sclerosis (MS), a juxtacortical lesion at the border between the gray matter (GM) and subcortical white matter (WM) may often involve the GM. A recently developed, phase-weighted magnetic resonance imaging (MRI) technique "phase difference enhanced imaging (PADRE)" can delineate the GM and WM clearly due to the difference in myelin concentration. We evaluated whether PADRE is useful for the detection of GM involvement in the juxtacortical MS lesions. METHODS: One neuroradiologist reviewed the conventional MRI in 13 MS patients and selected 48 juxtacortical lesions. At the first reading session with the conventional MRI alone (T2-weighted imaging, and two-dimensional and three-dimensional fluid-attenuated inversion recovery), two other neuroradiologists classified the lesions into three patterns according to their anatomical locations: (a) subcortical WM lesions involving the subcortical WM alone; (b) intracortical (IC) lesions involving the GM alone; (c) mixed GM/subcortical WM (mixed) lesions involving the both subcortical WM and GM. We defined the subcortical WM as a WM within a distance of 10 mm from inner edge of the GM. For the analyses, we excluded the white matter lesions further than 10 mm from inner edge of the GM. At the second reading session MRI and PADRE were available and the radiologists re-evaluated their prior classification. RESULTS: At the first reading session, 27 lesions were classified as (a), 1 as (b), and 20 as (c). Therefore, a total of 21 lesions (44%) were judged to involve the GM. At the second reading session, the classification of 15 (31%) lesions changed; all 15 lesions were judged to involve the GM on the PADRE. Interobserver agreement (kappa value) was 0.84 for the first- and 0.95 for the second reading session. CONCLUSION: PADRE is useful for detecting GM involvement of the juxtacortical MS lesions.

Improved Detection of Cortical Gray Matter Involvement in Multiple Sclerosis with Quantitative Susceptibility Mapping.

RATIONALE AND OBJECTIVES: Quantitative susceptibility mapping (QSM) is a novel technique which allows determining the bulk magnetic susceptibility distribution of tissue in vivo from gradient echo magnetic resonance (MR) phase images. Our purpose was to evaluate if there is additional diagnostic value of QSM images in detecting the cortical gray matter involvement in multiple sclerosis (MS) patients. MATERIALS AND METHODS: Our institutional review board approved this study. Conventional MR imaging, including T2-weighted imaging and two- or three-dimensional fluid-attenuated inversion recovery images, and QSM imaging examinations were performed in 27 patients (19 male and eight female) with MS. Two radiologists (radiologists 1 and 2) assessed the MS lesions in the following 3 anatomic regions: intracortical, mixed white matter-gray matter (WM-GM), and juxtacortical regions. The numbers of lesions per region category were compared between conventional MR images with and without QSM images. RESULTS: For radiologists 1 and 2, QSM images identified 6 (50.0%) and 7 (50.0%) additional lesions that were not seen in the conventional MR images, respectively. In a lesion-by-lesion analysis, the substantial fraction (20 [25.3%] of 79 at radiologist 1, 22 [29.7%] of 74 at radiologist 2) of juxtacortical white matter lesions on the conventional MR images were scored as mixed WM-GM lesions with QSM images. CONCLUSIONS: Our preliminary results suggest that the MR imaging with QSM may increase the sensitivity in cortical lesion detection in the MS brain and improved distinction between juxtacortical and mixed WM-GM lesions.

Systemic lupus erythematosus: prediction by MRI of the subsequent development of brain lesions.

RATIONALE AND OBJECTIVES: Many patients with systemic lupus erythematosus (SLE) manifest the recurrence of new brain lesions on follow-up magnetic resonance imaging (MRI) scans. We assessed whether the initial MRI findings help to predict the subsequent development of brain lesions in patients with SLE. MATERIALS AND METHODS: We enrolled 64 patients with SLE who had undergone initial and follow-up MRI studies. Two radiologists reviewed and categorized the initial MRI findings and divided the patients into those with no lesions on the initial and follow-up MRI scans (group A, n = 18), those with lesions on the initial scans only (group B, n = 32), and those with lesions on the first and new lesions on the follow-up MRI scans (group C, n = 14). We then looked for independent predictors of the subsequent development of brain lesions, such as antiphospholipid syndrome (APS) and findings on the initial MRI studies. RESULTS: The incidence of lacunar and localized cortical infarcts was significantly greater in group C than group B (50% vs. 0%, P < .001 and 50% vs. 9%, P < .05, respectively). Multivariate logistic regression analysis indicated that lacunar or localized cortical infarcts on the initial MRI scans were independent predictors of the subsequent development of brain lesions (odds ratio [OR]: 5.412, 95% confidence interval [CI]: 1.18-24.85, P = .03), whereas the presence of APS was not (OR: 0.621, 95% CI: 0.18-2.19). CONCLUSIONS: The presence of lacunar and/or localized cortical infarcts on initial MRI scans may predict the development of new brain lesions in patients with SLE.