Early Magnetic Resonance Imaging Research Articles

Prognostic value of early magnetic resonance imaging in the morbidity and mortality of traumatic spinal cord injury

ObjectiveTo assess in individuals with traumatic spinal cord injury (TSCI) the relationship between mortality and need for ICU and early magnetic resonance imaging (MRI), analyzing spinal parenchymal alterations, disruption of vertebral ligaments (DVL) and spinal cord compression (SCC). DesignRetrospective study. SettingThird-level hospital, Spinal Cord Injury Unit and ICU. PatientsIndividuals with acute TSCI between 2010 and 2019. InterventionAnalysis of MRI performed in the first 72 h. Variables of interestAdmission to ICU and mortality. Results269 cases collected. The pattern that demonstrated higher mortality was cord hemorrhage (16.7%) for 12.5% ​​of single-level edema and 6.5% of multilevel edema (p = 0.125). The same happened with ICU admissions: 69.0% in hemorrhage, 60.2% in multilevel edema and 46.3% in short edema (p = 0.018).Analyzing CCM, mortality was 13.4% with 59.2% of ICU admissions, for 2.2% and 42.2% of individuals without cord compression (p = 0.020 and p = 0.003). The figures of death and ICU admission among cord injuries with DVL were 15.0% and 67.3%, for 6.2% and 44.4% of the individuals without DLV (p < 0.001 and p = 0.013). ConclusionsThe presence of spinal cord hemorrhage, SCC and DVL was associated with a higher admission in ICU. A significant increase in mortality was observed in cases with SCC and DVL.

An exploratory study to identify neonatal arterial ischemic stroke: A single-center study

BackgroundNeonatal arterial ischemic stroke (NAIS) presents as seizures, including convulsions, subtle seizures, and apnea, and most patients experience neurological sequelae. Diagnosis is often delayed owing to low test sensitivity. The present study aimed to identify the early clinical diagnostic factors for NAIS in neonates with seizures. MethodsThe present study included 54 patients born at ≥36 weeks of gestation during the last 15 years who presented to the neonatal intensive care unit with neonatal seizures and underwent brain magnetic resonance imaging (MRI), 6 of whom were diagnosed with NAIS. Maternal background, clinical characteristics, and transcranial pulsed Doppler sonography results were retrospectively reviewed. ResultsOf the 24 patients who presented with convulsions or subtle seizures, 3 (13%) were diagnosed with NAIS and 3 of 30 patients (10%) presented with apnea. Maternal premature ventricular contraction complications were higher in the NAIS group than in the non-NAIS group (p = 0.01). NAIS group showed lower mean middle cerebral artery (MCA) resistance index (RI) was lower the non-NAIS group (p = 0.009), while the left–right RI difference (p = 0.019), mean MCA blood velocity (MnV; p = 0.04), and left–right MnV difference (p < 0.001) in cerebral blood flow velocities (CBFVs) were higher in the NAIS group. ConclusionsOur results revealed that maternal arrhythmia may be a diagnostic factor for NAIS in neonates with seizures. Early brain MRI is essential in neonates with seizures and findings of low MCA-RI, high MCA-MnV, or high left–right difference in CBFVs to distinguish between NAIS and non-NAIS.

Acute Magnetic Resonance Imaging Predictors of Chronic Motor Function and Tissue Sparing in Rat Cervical Spinal Cord Injury.

Predicting functional outcomes from spinal cord injury (SCI) at the acute setting is important for patient management. This work investigated the relationship of early magnetic resonance imaging (MRI) biomarkers in a rat model of cervical contusion SCI with long-term functional outcome and tissue sparing. Forty rats with contusion injury at C5 at either the spinal cord midline (bilateral) or over the lateral cord (unilateral) were examined using in vivo multi-modal quantitative MRI at 1 day post-injury. The extent of T2-weighted hyperintensity reflecting edema was greater in the bilateral model compared with the unilateral injury. Diffusion tensor imaging (DTI) exhibited microscopic damage in similar regions of the cord as reductions in fractional anisotropy (FA) and mean diffusivity (MD), but DTI parameter maps were also confounded by the presence of vasogenic edema that locally increased FA and MD. In comparison, filtered diffusion-weighted imaging (fDWI) more clearly delineated the location of acute axonal damage without effects of vasogenic edema. Pairwise correlation analysis revealed that 28-day motor functional outcomes were most strongly associated with the extent of edema (R = -0.69). Principal component analysis identified close associations of motor functional score with tissue sparing, the extent of edema, lesion area, and injury type (unilateral or bilateral). Among the diffusion MRI parameters, lesion areas measured with fDWI had the strongest association with functional outcome (R = -0.41). Voxelwise correlation analysis identified a locus of white matter damage associated with function in the dorsal white matter, although this was likely driven by variance across the two injury patterns (unilateral and bilateral injury). Nonetheless, correlation with motor function within the damaged region found in the voxelwise analysis outperformed morphological lesion area measurement as a predictor of chronic function. Collectively, this study characterized anatomical and diffusion MRI signatures of acute SCI at cervical spine and their association with chronic functional outcomes and histological results.

Early stage T1-weighted perfusion magnetic resonance imaging: a factor that predicts local control response in patients with meningioma who underwent gamma-knife radiosurgery

ABSTRACT Background Gamma-knife radiosurgery (GKRS) is an alternative treatment option for selected intracranial meningiomas. The study’s aim is to demonstrate the advantages of T1-weighted perfusion magnetic resonance imaging (T1-PMRI) by measuring the volume transfer coefficient (Ktrans) values in the prediction of local response for patients with meningioma who have undergone GKRS consecutively. Methods The data of patients diagnosed radiologically with WHO grade 1 intracranial meningiomas was collected prospectively. The patients who were treated consecutively with GKRS at our institution (September 2017–September 2018) were included. After GKRS, the patients were followed up at the defined periods with routine contrast-enhanced MRI and T1-PMRI by measuring the Ktrans. The comparison between the pre-treatment and third-month post-treatment (PO3M) Ktrans was done using the Wilcoxon signed-rank test. Results Thirty-one patients with 36 tumors have undergone GKRS. Twenty-two patients were female. The mean age was 55.3 years. The mean pre-GKRS volume was 7.67 ccs. The mean 50% radiation isodose was 12.2 Gy. The local tumor control rate was 100%. Fourteen tumors were regressed fully at the last MRI. PO3M Ktrans decreased when compared with the pre-GKRS values (p < 0.0001). However, the numerical decrease in tumor volumes on contrast-enhanced MRI was not statistically significant (p = 0.117). Conclusion Changes between Ktrans on PO3M and pre-GKRS T1-PMRI were more useful in determining the early response to GKRS in patients with meningioma than volumetric changes. Therefore, Ktrans should be taken as a reference to predict the early response to GKRS in follow-up imaging scans.

The prognostic significance of early blood neurofilament light chain concentration and magnetic resonance imaging variables in relapse-onset multiple sclerosis.

BackgroundImproved prognostication remains vital in multiple sclerosis to inform personalized treatment approaches. Blood neurofilament light (bNfL) is a promising prognostic biomarker, but to what extent it provides additional information, independent of established MRI metrics, is yet to be established.MethodsWe obtained all available bNfL data for 133 patients from a longitudinal observational cohort study. Patients were dichotomized into good or poor outcome groups based upon clinical and cognitive assessments performed 15 years after a clinically isolated syndrome. We performed longitudinal modeling of early NfL and MRI variables to examine differences between outcome groups.ResultsThe bNfL dataset was incomplete, with one to three (mean 1.5) samples available per participant. Within 3 months of onset, bNfL was similar between groups. The bNfL concentration subsequently decreased in those with a good outcome, and remained persistently elevated in those with a poor outcome. By year 5, NfL in the poor outcome group was approximately double that of those with a good outcome (14.58 [10.40–18.77] vs. 7.71 [6.39–9.04] pg/ml, respectively). Differences were reduced after adjustment for longitudinal changes in T2LV, but trends persisted for a greater rate of increase in NfL in those with a poor outcome, independent of T2LV.ConclusionsThis analysis requires replication in cohorts with more complete bNfL datasets, but suggests that persistently elevated blood NfL may be more common in patients with a poor long‐term outcome. Persistent elevation of blood NfL may provide additional prognostic information not wholly accounted for by standard monitoring techniques.

A prospective study of cancer detection rates following early repeat imaging and biopsy of PI-RADS 4 and 5 regions of interest exhibiting no clinically significant prostate cancer on prior biopsy.

We aimed to determine cancer detection rates following early repeat multiparametric magnetic resonance imaging (mpMRI) and biopsy of Prostate Imaging-Reporting and Data System (PI-RADS), v2.1 4 and 5 regions of interest (ROI) exhibiting no clinically significant prostate cancer (csPCa) on prior biopsy and to identify predictors for these missed csPCa. Between January 2019 and August 2020, 36 men with 38 PI-RADS 4 or 5 ROI with no evidence of csPCa (defined as Gleason grade group [GGG] >1) on prior MRI fusion target biopsy (MRFTB) + systematic biopsy (SB) were invited to participate in the present prospective study. All men underwent repeat mpMRI and persistent PI-RADS >2 ROI were advised to undergo repeat MRFTB + SB. Cancer detection rates of any and csPCa were determined. Relative risk was calculated to analyze association of baseline variables with the finding of csPCa on repeat biopsy. Of the 38 initial PI-RADS 4 and 5 ROI, on followup mpMRI, 14 were downgraded to PI-RADS 1/2 and, per protocol, did not undergo repeat biopsy and; eight (33%), 12 (50%), and four (17%) were PI-RADS 3, 4, and 5, respectively. Of these 24 persistently suspicious mpMRI ROI, 20 (83%) underwent repeat biopsy and six (30%), six (30%), and eight (40%) were benign, GGG 1, and GGG >1, respectively. Only prostate-specific antigen ≥10 ng/mL was a predictor for missed csPCa. Our prospective study supports a recommendation for early repeat mpMRI of all PI-RADS 4 or 5 ROI exhibiting no csPCa, with repeat MRFTB + SB of persistent PI-RADS >2 ROI.

The Utility of Early Brain MRI for Patients with Neurofibromatosis Type 1 and Optic Pathway Glioma: A Long-Term Follow-Up in a Tertiary Referral Hospital.

Screening studies have shown detection of optic pathway gliomas (OPGs) in 8 to 31% of children with neurofibromatosis type 1 (NF1). Many of those affected show prolonged indolent phases, but others develop vision disturbances even before diagnosis and treatment. We assessed the clinical presentation at diagnosis, location, natural progression, and risk factors for impaired vision of OPG. The clinical database of the NF1 multidisciplinary clinic of Schneider Children's Medical Center of Israel was reviewed for all patients diagnosed and followed with NF1 during 2007 to 2019. OPG was diagnosed by hyperintensity and thickening along the optic pathway on T2-weighted brain magnetic resonance imaging (MRI), with or without contrast enhancement. Of 257 children with NF1 who underwent MRI, 57 (22%) were diagnosed with OPG; 31 (54%) were females. Twenty-five (44%) had familial NF1. Fifteen (26%) who exhibited tumor progression and worsening in ophthalmic examinations required treatment. Post-chiasmatic glioma was a predictive factor for treatment (p < 0.05), whereas MRI done later and female gender were not significant. Four patients who eventually needed therapy had normal ophthalmic examinations at least 1 year prior to their first MRI. For 6 (40%) of the patients treated, vision continued to worsen. Our findings demonstrate that normal ophthalmic examinations do not always exclude OPG in children with NF1. Early brain MRI before age 36 months may detect OPG, lead to better follow-up and early treatment, and help improve vision outcome.

Adjustable and Magnetic Resonance Imaging Conditional Implantation of a Licox Brain Tissue Oxygenation Probe in Neurosurgery: Technical Note

Continuous bedside brain tissue oxygen monitoring is an essential part of managing comatose patients with acute brain injury. Maintenance of adequate brain oxygenation has been established as an important goal in neurocritical care to prevent patients from secondary ischemia. As patients with subarachnoid hemorrhage and traumatic brain injury often require early magnetic resonance imaging, conventionally implanted metal bolts are disadvantageous due to massive artifacts. We hereby report a novel technique of magnetic resonance imaging conditional bedside implantation of a brain tissue oxygenation probe. We performed bedside implantation of a Licox brain tissue oxygenation probe with a peripheral venous cannula that is placed through a plastic bolt placed on a burr hole. Bedside implantation of a Licox brain tissue oxygenation probe was successfully performed in a novel fashion. This article describes the feasibility of a novel technique of bedside implantation of a Licox brain tissue oxygenation probe, resulting in a length-adjustable insertion and rigid fixation without metal artifacts in early magnetic resonance imaging.

Remodeling of Epidural Fluid Hematoma after Uniportal Lumbar Endoscopic Unilateral Laminotomy with Bilateral Decompression: Comparative Clinical and Radiological Outcomes with a Minimum Follow-up of 2 Years.

Retrospective cohort study. To evaluate the clinical and radiological effects of epidural fluid hematoma in the medium term after lumbar endoscopic decompression. There is limited literature comparing the effect of postoperative epidural fluid hematoma after uniportal endoscopic decompression. Magnetic resonance imaging (MRI) and clinical evaluation were performed for patients with single-level uniportal endoscopic lumbar decompression with a minimum follow-up of 2 years. A total of 126 patients were recruited with a minimum follow-up of 26 months. The incidence of epidural fluid hematoma was 27%. Postoperative MRI revealed a significant improvement in the postoperative dura sac area at postoperative day 1 and at the upper endplate at 6 months in the hematoma cohort (39.69±15.72 and 26.89±16.58 mm2) as compared with the nonhematoma cohort (48.92±21.36 and 35.1±20.44 mm2), respectively (p <0.05); and at the lower endplate on postoperative 1 day in the hematoma cohort (51.18±24.69 mm2) compared to the nonhematoma cohort (63.91±27.92 mm2) (p <0.05). No significant difference was observed in the dura sac area at postoperative 1 year in both cohorts. The hematoma cohort had statistically significant higher postoperative 1-week Visual Analog Scale (VAS; 3.32±0.68) pain and Oswestry Disability Index (ODI; 32.65±5.56) scores than the nonhematoma cohort (2.99±0.50 and 30.02±4.84, respectively; p <0.05). No significant difference was found at the final follow-up VAS, ODI, and MRI dura sac area. Epidural fluid hematoma is a common early postoperative MRI finding in lumbar endoscopic unilateral laminotomy with bilateral decompression. Conservative management is the preferred treatment option for patients who do not have a neurological deficit. Symptoms last only a few days and are self-limiting. A common endpoint is a remodeled fluid hematoma and the subsequent expansion of the dura sac area.

A Prospective Study of Magnetic Resonance Imaging-guided Focal Salvage High-dose-Rate Brachytherapy for Radiorecurrent Prostate Cancer: Updated Results of 30 Patients

PurposeLimited prospective data on focal salvage high-dose-rate (HDR) prostate brachytherapy is available. We sought to explore the toxicities, health-related quality of life (HRQoL), and efficacy of focal salvage HDR brachytherapy in a prospective clinical trial. This report presents the updated results of previously published data. Methods and MaterialsPatients with locally recurrent prostate cancer after previous external beam radiation therapy and/or brachytherapy were enrolled. Patients received magnetic resonance imaging (MRI)-guided, ultrasound-based focal HDR brachytherapy delivered over 2 fractions of 13.5 Gy delivered 1 to 2 weeks apart. Androgen deprivation therapy (ADT) was not used. ResultsThirty patients were treated between 2012 and 2019. At a median follow-up time of 39 months, the 3-year biochemical failure-free rate was 61.8% (95% confidence interval, 44.0%-86.6%), and the 3-year ADT/salvage therapy-free rate was 86.0% (95% confidence interval, 74.1%-99.8%). Seventeen patients experienced subsequent biochemical failure, 9 received ADT and/or further local salvage, and no patients died of prostate cancer. Of the 28 patients who had posttreatment MRI, 26 had a local treatment response. No acute grade ≥3 genitourinary/gastrointestinal toxicity was observed. One temporary late grade 3 genitourinary toxicity event occurred, but no late grade ≥3 gastrointestinal toxicity was seen. No significant decline in urinary or bowel HRQoL was observed. ConclusionsFocal salvage HDR brachytherapy has a favorable side effect profile, no significant decline in HRQoL, and the 3-year biochemical control rates are in line with those of other salvage options. Early MRI response at the treated site is common, but does not preclude subsequent biochemical failure.

Brain Tissue Damage Induced by Multimodal Neuromonitoring In Situ during MRI after Severe Traumatic Brain Injury: Incidence and Clinical Relevance.

Both neuromonitoring and early magnetic resonance imaging (MRI) provide crucial information for treatment management and prognosis in patients with severe traumatic brain injury (sTBI). So far, neuromonitoring in situ impedes the routine implementation of MRI due to safety concerns. We aimed to evaluate the brain tissue damage induced by inserted neuromonitoring devices and its clinical relevance. Nineteen patients with sTBI and being exposed to at least one MRI with neuromonitoring in situ and one follow-up MRI after neuromonitoring removal were analyzed. All MRIs were reviewed for specific tissue damage. Three females and sixteen males (aged 20–74 years, mean 42.8 years) with an initial median GCS of 5 (range 3–8) were analyzed. No lesion was observed in six patients (31.6%), whereas another six patients (31.6%) demonstrated a detectable probe trajectory. Probe-related tissue damage was visible in seven patients (36.8%) with the size of the lesion prone to further enlarge with increasing cumulative duration of MRI examinations. Upon interdisciplinary evaluation, the lesions were not considered clinically relevant. Neuromonitoring probes in situ during MRI examinations may cause local brain tissue damage, yet without any clinical implications if placed correctly. Therefore, indications must be strictly based on joint decision from all involved disciplines.

Early detection of ischemic brain injuries by diffusion-weighted imaging after radiofrequency ablation for fetal reduction in monochorionic pregnancies.

This study aimedto investigate the additional advantages of magnetic resonance imaging (MRI), particularly diffusion-weighted imaging (DWI) over fetal ultrasound in the detection of acute ischemic cerebral injuries in complicated monochorionic (MC) pregnancies that underwent selective reduction by radiofrequency ablation (RFA). This prospective cohort study was conducted on 40 women with complicated MC pregnancies who were treated by RFA. Fetal brain imaging by DWI and conventional MRI was performed either in the early (within 10 days after RFA) or late phase (after 3-6 weeks) in the surviving fetuses to detect both acute and chronic ischemic injuries. The presence of anemia after RFA was also evaluated by Doppler ultrasound. Overall, 13 of the total 43 fetuses (30.23%) demonstrated MRI abnormalities with normal brain ultrasound results including germinal matrix hemorrhage (GMH), extensive cerebral ischemia, and mild ventriculomegaly. Although seven fetuses with GMH eventually survived, fetuses that demonstrated ischemic lesions and ventriculomegaly on MRI died in the uterus. The absence of abnormal cerebral lesions or anemia on ultrasound and Doppler exams does not necessarily rule out fetal brain ischemia. Performing early MRI, particularly DWI seems to be a reasonable option for detection of early intracranial ischemic changes and better management of complicated multiple pregnancies which were treated by RFA.

Ventricular Volume in Infants Born Very Preterm: Relationship with Brain Maturation and Neurodevelopment at Age 4.5 Years

To evaluate the relationship of quantitative ventricular volume with brain maturation and neurodevelopmental outcomes at age 4.5years in children born very preterm. T1-weighted imaging, diffusion tensor imaging, and magnetic resonance spectroscopy were performed shortly after birth (n=212) and at term-equivalent age (TEA) (n=194). Intraventricular hemorrhage (IVH) grade and white matter injury (WMI) volume were measured on early T1-weighted magnetic resonance imaging (MRI) scans. Total cerebral volume and ventricular volume were quantified using the Multiple Automatically Generated Templates-Brain pipeline. At age 4.5years, 178 children (84%) underwent cognitive and motor assessments. Multivariable linear regression was used to examine the relationships between ventricular volume and neurodevelopmental outcomes. Generalized estimating equations were used to account for repeated measures when analyzing neonatal MRI data. All models accounted for sex, postmenstrual age at scan, WMI volume, IVH grade, and total cerebral volume and were corrected for multiple comparisons. On early MRI, 97 infants had IVH (grade 1, n=22; grade 2, n=66; grade 3, n=9), and 68 had WMI (median, 44mm3; IQR, 21-296mm3). IQ at 4.5years was associated with MRI ventricular volume at the early (β=-0.64; P<.001) and TEA (β=-0.44, P<.001) time points. Motor outcomes were associated with ventricular volume at TEA (β=-0.84, P=.01). Greater ventricular volume independently predicted lower fractional anisotropy in corpus callosum (genu: β=-0.0008, P=.002; splenium: β=-0.003, P<.001) and optic radiations (β=-0.001, P=.004); ventricular volume did not predict the N-acetylaspartate/choline ratio. In children born very preterm, neonatal ventricular size was associated with 4.5-year neurodevelopmental outcomes. Our findings suggest that white matter maturation may be abnormal in the setting of enlarged ventricular size beyond that expected from concurrent brain injuries.

A Descriptive Review of the Impact of Patient Motion in Early Childhood Resting-State Functional Magnetic Resonance Imaging

Resting-state functional magnetic images (rs-fMRIs) can be used to map and delineate the brain activity occurring while the patient is in a task-free state. These resting-state activity networks can be informative when diagnosing various neurodevelopmental diseases, but only if the images are high quality. The quality of an rs-fMRI rapidly degrades when the patient moves during the scan. Herein, we describe how patient motion impacts an rs-fMRI on multiple levels. We begin with how the electromagnetic field and pulses of an MR scanner interact with a patient’s physiology, how movement affects the net signal acquired by the scanner, and how motion can be quantified from rs-fMRI. We then present methods for preventing motion through educational and behavioral interventions appropriate for different age groups, techniques for prospectively monitoring and correcting motion during the acquisition process, and pipelines for mitigating the effects of motion in existing scans.

An Updated Overview of MRI Injuries in Neonatal Encephalopathy: LyTONEPAL Cohort.

Background: Brain magnetic resonance imaging (MRI) is a key tool for the prognostication of encephalic newborns in the context of hypoxic−ischemic events. The purpose of this study was to finely characterize brain injuries in this context. Methods: We provided a complete, descriptive analysis of the brain MRIs of infants included in the French national, multicentric cohort LyTONEPAL. Results: Among 794 eligible infants, 520 (65.5%) with MRI before 12 days of life, grade II or III encephalopathy and gestational age ≥36 weeks were included. Half of the population had a brain injury (52.4%); MRIs were acquired before 6 days of life among 247 (47.5%) newborns. The basal ganglia (BGT), white matter (WM) and cortex were the three predominant sites of injuries, affecting 33.8% (n = 171), 33.5% (n = 166) and 25.6% (n = 128) of participants, respectively. The thalamus and the periventricular WM were the predominant sublocations. The BGT, posterior limb internal capsule, brainstem and cortical injuries appeared more frequently in the early MRI group than in the late MRI group. Conclusion: This study described an overview of brain injuries in hypoxic−ischemic neonatal encephalopathy. The basal ganglia with the thalamus and the WM with periventricular sublocation injuries were predominant. Comprehensive identification of brain injuries in the context of HIE may provide insight into the mechanism and time of occurrence.

Early imaging predictors of fetal cerebral ischemic injury in monochorionic twin pregnancy complicated by spontaneous single intrauterine death.

Monochorionic twin pregnancies are at increased risk of single intrauterine death (sIUD) and subsequent brain injury in the surviving twin owing to shared placentation. We assessed the association between middle cerebral artery peak systolic velocity (MCA-PSV) and cerebral injury on magnetic resonance imaging (MRI) and examined the association between cerebral findings on diffusion-weighted imaging (DWI) and those on T2-weighted imaging following spontaneous sIUD. This was a retrospective cohort study of monochorionic pregnancies complicated by spontaneous sIUD followed at a tertiary center between January 2008 and January 2020. Pregnancies with sIUD following laser treatment, those with selective feticide, double IUD occurring on the same day or sIUD before 14 weeks' gestation were excluded, as were cases in which MCA-PSV was not measured or DWI-MRI was not performed. The ability of MCA-PSV Doppler to predict subsequent cerebral injury on MRI was assessed, and DWI findings were analyzed and compared with those on susceptibility-weighted imaging (SWI) and T2-weighted MRI to determine its diagnostic accuracy. We assessed 64 monochorionic pregnancies complicated by spontaneous sIUD. Of these, 47 (73.4%) pregnancies underwent fetal brain MRI and met the inclusion criteria. Sixteen (34.0%) of these fetuses demonstrated cerebral injury on MRI. The median interval between the diagnosis of sIUD and MRI examination was 5 days. Fetuses with increased MCA-PSV > 1.5 multiples of the median (MoM) following sIUD were significantly more likely to demonstrate cerebral injury on MRI than were those with normal MCA-PSV (68.8% vs 38.7%; P = 0.05). The sensitivity and specificity of MCA-PSV > 1.5 MoM for predicting cerebral injury on MRI were 68.8% (95% CI, 41.3-88.9%) and 61.3% (95% CI, 42.2-78.2%), respectively. Patterns of early cerebral injury on T2-weighted and SWI-MRI included acute or subacute tissue swelling (n = 6), parenchymal atrophy (n = 7), loss of cortical ribbon (n = 1) and hemorrhage (n = 8). Early MRI within approximately 2 weeks after the diagnosis of sIUD demonstrated abnormal DWI along with coexisting SWI and T2-weighted sequelae in 56.3% (9/16) of cases. When DWI was normal and a second MRI examination was performed later (n = 7), there were no ischemic changes evident on T2-weighted imaging. Increased MCA-PSV is associated with, but predicts poorly, cerebral injury after sIUD. Early MRI with DWI within approximately 2 weeks after the diagnosis of sIUD is valuable in identifying any cerebral injury. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

CMR Imaging 6 Months After Myocarditis Associated with the BNT162b2 mRNA COVID-19 Vaccine.

Temporal association between BNT162b2 mRNA COVID-19 vaccine and myocarditis (PCVM) has been reported. We herein present early and 6-month clinical follow-up and cardiac magnetic resonance imaging (CMR) of patients with PVCM. A retrospective collection of data from 15 patients with PCVM and abnormal CMR was performed. Clinical manifestation, laboratory data, hospitalizations, treatment protocols, and imaging studies were collected early (up to 2 months) and later. In nine patients, an additional CMR evaluation was performed 6 months after diagnosis. PCVM was diagnosed in 15 patients, mean age 17 ± 1 (median 17.2, range 14.9–19 years) years, predominantly in males. Mean time from vaccination to onset of symptoms was 4.4 ± 6.7 (median 3, range 0–28) days. All patients had CMR post diagnosis at 4 ± 3 (median 3, range 1–9) weeks, 4/5 patients had hyper enhancement on the T2 sequences representing edemaQuery, and 12 pathological Late glandolinium enhancement. A repeat scan performed after 5–6 months was positive for scar formation in 7/9 patients. PCVM is a rare complication, affecting predominantly males and appearing usually within the first week after administration of the second dose of the vaccine. It usually is a mild disease, with clinical resolution with anti-inflammatory treatment. Late CMR follow up demonstrated resolution of the edema in all patients, while some had evidence of residual myocardial scarring.

The importance of surgeon judgment in obtaining early magnetic resonance imaging to prevent delays in care for acute subacromial injury: a retrospective comparative cohort study

Background: The purpose of this study was to evaluate the role of initial assessment of acute subacromial injury by an orthopaedic surgeon to identify surgical lesions that would benefit from early imaging. Methods: Patients with subacromial injury were identified. Patients who had MRI ordered at the initial visit for suspicion of a surgical lesion comprised the study group. The remaining patients were treated conservatively. Results: A total of 367 patients were identified; 298 (81%) underwent conservative treatment, 84 of whom had later MRI, and 69 (19%) had an MRI ordered initially. In the early MRI group, 31 (44.9%) underwent surgery an average of 85 days from presentation compared to 38 (12.8%) in the conservative group who underwent surgery 140 days from presentation (P=0.019). MRI scan review revealed that 41/69 (59.4%) patients in the early MRI group had full-thickness rotator cuff tear compared with 33/84 (39.3%) in the conservative group with MRI (P=0.020). Partial-thickness tears were noted in 8/69 (11.6%) in the early MRI group. In the conservative group that subsequently had MRI, 17/84 (20.2%) had a partial-thickness tear. Conclusions: Nearly 60% of patients undergoing initial MRI based on orthopaedic surgeon judgment had a full-thickness rotator cuff tear, significantly more than patients treated conservatively upon initial evaluation. Patients who first undergo conservative treatment for suspected acute subacromial injury experience a significant delay both in MRI and surgical intervention. Surgeon judgment is an important factor in the decision to obtain MRI in acute subacromial injury to prevent delays in care. Level of Evidence: Level III.

Early Thalamocortical Reperfusion Leads to Neurologic Recovery in a Rodent Cardiac Arrest Model.

Cerebral blood flow (CBF) plays an important role in neurological recovery after cardiac arrest (CA) resuscitation. However, the variations of CBF recovery in distinct brain regions and its correlation with neurologic recovery after return of spontaneous circulation (ROSC) have not been characterized. This study aimed to investigate the characteristics of regional cerebral reperfusion following resuscitation in predicting neurological recovery. Twelve adult male Wistar rats were studied, ten resuscitated from 7-min asphyxial CA and two uninjured rats, which were designated as healthy controls (HCs). Dynamic changes in CBF in the cerebral cortex, hippocampus, thalamus, brainstem, and cerebellum were assessed by pseudocontinuous arterial spin labeling magnetic resonance imaging, starting at 60min after ROSC to 156min (or time to spontaneous arousal). Neurologic outcomes were evaluated by the neurologic deficit scale at 24h post-ROSC in a blinded manner. Correlations between regional CBF (rCBF) and neurological recovery were undertaken. All post-CA animals were found to be nonresponsive during the 60-156min post ROSC, with reductions in rCBF by 24-42% compared with HC. Analyses of rCBF during the post-ROSC time window from 60 to 156min showed the rCBF recovery of hippocampus and thalamus were positively associated with better neurological outcomes (rs = 0.82, p = 0.004 and rs = 0.73, p < 0.001, respectively). During 96min before arousal, thalamic and cortical rCBF exhibited positive correlations with neurological recovery (rs = 0.80, p < 0.001 and rs = 0.65, p < 0.001, respectively); for predicting a favorable neurological outcome, the thalamic rCBF threshold was above 50.84ml/100g/min (34% of HC) (area under the curve of 0.96), whereas the cortical rCBF threshold was above 60.43ml/100g/min (38% of HC) (area under the curve of 0.88). Early magnetic resonance imaging analyses showed early rCBF recovery in thalamus, hippocampus, and cortex post ROSC was positively correlated with neurological outcomes at 24h. Our findings suggest new translational insights into the regional reperfusion and the time window that may be critical in neurological recovery and warrant further validation.

Ipsilesional volume loss of basal ganglia and thalamus is associated with poor hand function after ischemic perinatal stroke

BackgroundPerinatal stroke (PS) is the leading cause of hemiparetic cerebral palsy (CP). Involvement of the corticospinal tract on neonatal magnetic resonance imaging (MRI) is predictive of motor outcome in patients with hemiparetic CP. However, early MRI is not available in patients with delayed presentation of PS and prediction of hemiparesis severity remains a challenge.AimsTo evaluate the volumes of the basal ganglia, amygdala, thalamus, and hippocampus following perinatal ischemic stroke in relation to hand motor function in children with a history of PS and to compare the volumes of subcortical structures in children with PS and in healthy controls.MethodsTerm born PS children with arterial ischemic stroke (AIS) (n = 16) and with periventricular venous infarction (PVI) (n = 18) were recruited from the Estonian Pediatric Stroke Database. MRI was accuired during childhood (4-18 years) and the volumes of the basal ganglia, thalamus, amygdala and hippocampus were calculated. The results of stroke patients were compared to the results of 42 age- and sex-matched healthy controls. Affected hand function was evaluated by Assisting Hand Assessment (AHA) and classified by the Manual Ability Classification System (MACS).ResultsCompared to the control group, children with AIS had smaller volumes of the ipsi- and contralesional thalami, ipsilesional globus pallidus, nucleus accumbens and hippocampus (p < 0.005). Affected hand function in children with AIS was correlated with smaller ipsilesional thalamus, putamen, globus pallidus, hippocampus, amygdala and contralesional amygdala (r > 0.5; p < 0.05) and larger volume of the contralesional putamen and hippocampus (r < − 0.5; p < 0.05).In children with PVI, size of the ipsilesional caudate nucleus, globus pallidus, thalamus (p ≤ 0.001) and hippocampus (p < 0.03) was smaller compared to controls. Smaller volume of the ipsi- and contralesional thalami and ipsilesional caudate nucleus was correlated with affected hand function (r > 0.55; p < 0.05) in children with PVI.ConclusionsSmaller volume of ipsilesional thalamus was associated with poor affected hand function regardless of the perinatal stroke subtype. The pattern of correlation between hand function and volume differences in the other subcortical structures varied between children with PVI and AIS. Evaluation of subcortical structures is important in predicting motor outcome following perinatal stroke.