High Signal Intensity Lesions Research Articles

Lateral medullary infarction in a patient with Moyamoya disease associated with RNF213 variants: a case report

Background: Moyamoya disease (MMD) is a rare cerebrovascular disease radiologically characterized by progressive bilateral occlusion of the distal portion of the internal carotid artery and compensating collaterals. Herein, we report a case of medullary infarction in a patient with MMD.Case Report: We present the case of a 54-year-old male with hypertension, hyperlipidemia, and unstable angina with sudden onset dysarthria and ataxia. Diffusion-weighted and T2-weighted images of magnetic resonance imaging showed a high-signal intensity lesion on the right lateral medulla, suggestive of acute infarction. Transfemoral cerebral angiography also demonstrated bilateral middle cerebral artery (MCA) occlusion. Testing of the ring finger protein 213 (RNF213) gene revealed a homozygous p.R4810K variant that was possibly associated with posterior circulation involvement.Conclusion: When the MCA is occluded in MMD, there is a possibility that medullary infarction may occur due to the mechanism of increased hemodynamic stress on the anastomotic posterior vessels.

Osmotic demyelination syndrome with transient diabetes insipidus in postpartum female: a case report.

The authors present a case of 29-year-old female who presented with chief complaint of altered sensorium and quadriparesis. Two days prior to onset of symptoms, she underwent caesarean section, was kept on nil per oral and free fluid restriction, after which she had confusion, altered sensorium, and weakness in all four limbs. Sodium level was 170mEq/l. Urine osmolality and plasma osmolality was 150 and 410mOsm/kg of water, respectively. MRI showed high signal intensity lesion in pons suggestive of demyelination. She was diagnosed ODS with transient DI and quadriparesis, in postpartum period due to further rise in sodium after free fluid restriction and nil per oral. She was treated with desmopressin, 5% dextrose and 0.9% normal saline, her quadriparesis recovered and desmopressin was tapered and stopped over 45 days and discharged at stable state. ODS can rarely be associated with hypernatremia in postpartum female presenting as quadriparesis and altered sensorium. Clinicians should be familiar of ODS with hypernatremia with transient DI in postpartum period, which is reversible and can be managed by desmopressin and fluid replacement.

Clinical and Radiological Characteristics of Cervical Spondylotic Myelopathy in Young Adults: A Retrospective Case Series of Patients under Age 30.

Background and Objectives: Cervical spondylotic myelopathy (CSM) is a degenerative disease and occurs more frequently with age. In fact, the development of non-herniated CSM under age 30 is uncommon. Therefore, a retrospective case series was designed to clarify clinical and radiological characteristics of young adult patients with CSM under age 30. Materials and Methods: A total of seven patients, all men, with non-herniated, degenerative CSM under age 30 were retrieved from the medical records of 2598 hospitalized CSM patients (0.27%). Patient demographics and backgrounds were assessed. The sagittal alignment, congenital canal stenosis, dynamic canal stenosis, and vertebral slips in the cervical spine were radiographically evaluated. The presence of degenerative discs, intramedullary high-signal intensity lesions, and sagittal spinal cord compression on T2-weighted magnetic resonance images (MRIs) and axial spinal cord deformity on T1-weighted MRIs was identified. Results: All patients (100.0%) had relatively high daily sports activities and/or jobs requiring frequent neck extension. Cervical spine radiographs revealed the sagittal alignment as the "reverse-sigmoid" type in 57.1% of patients and "straight" type in 28.6%. All patients (100.0%) presented congenital cervical stenosis with the canal diameter ≤12 mm and/or Torg-Pavlov ratio <0.80. Furthermore, all patients (100.0%) developed dynamic stenosis with the canal diameter ≤12 mm and/or posterior vertebral slip ≥2 mm at the neurologically responsible segment in full-extension position. In MRI examination, all discs at the neurologically responsible level (100.0%) were degenerative. Intramedullary abnormal intensity lesions were detected in 85.7% of patients, which were all at the neurologically responsible disc level. Conclusions: Patients with non-herniated, degenerative CSM under age 30 are rare but more common in men with mild sagittal "reverse-sigmoid" or "straight" deformity and congenital canal stenosis. Relatively high daily activities, accumulating neck stress, can cause an early development of intervertebral disc degeneration and dynamic canal stenosis, leading to CSM in young adults.

Uncommon cause of trigeminal neuritis and central nervous system involvement by herpes labialis: a case report

BackgroundTrigeminal neuropathy is characterized by numbness in the region innervated by the trigeminal nerves, with or without neuropathic weakness in the muscles of mastication. Trigeminal neuritis is a form of trigeminal neuropathy in which the lesion is caused by an inflammation. Herein, we report a patient with trigeminal neuritis due to central nervous system (CNS) involvement of herpes labialis (HL) infection, which was successfully treated with anti-viral and anti-inflammatory agents.Case presentationA young healthy female presented with numbness in the left hemiface for two weeks. She had a preceding typical HL infection on left facial lip one week before the sensory symptom onset. Brain magnetic resonance imaging revealed high signal intensities and asymmetrical thickening with enhancement along the cisternal segment of the left trigeminal nerve. Additionally, brain MR angiography showed multifocal stenoses in the M1 segment of the middle cerebral artery and the cavernous portion of the internal carotid artery. Cerebrospinal fluid (CSF) examination showed mild pleocytosis with normal protein level, glucose ratio, but CSF polymerase chain reaction assay for specific anti-viral antibodies including herpes simplex virus was negative, and CSF culture also did not identify a specific pathogen. The results of serologic testing including tumor markers and autoimmune markers were all unremarkable. A tentative diagnosis of trigeminal neuritis as a complication of HL involving the CNS was made considering the clinical, neuroradiological, and laboratory findings of the patient. Therefore, the patient was treated with intravenous methylprednisolone and acyclovir for 10 days. After the treatments, her sensory disturbance was markedly improved. Brain MRI at the 3-month follow-up also demonstrated improvement of previously identified high signal intensity lesions and multifocal intracerebral artery stenoses.ConclusionHL is usually a self-limiting, benign disease without complications, but rarely presents as trigeminal neuritis due to CNS involvement. Therefore, meticulous evaluation may be necessary if trigeminal neuritis or CNS involving symptoms occur after HL.

Cytotoxic lesions of the corpus callosum after COVID-19 vaccination

A 23-year-old previously healthy man (Patient 1) and a 33-year-old woman with a past history of depression (Patient 2) developed neurological symptoms approximately 1 week after receipt of the first COVID-19 mRNA vaccination and deteriorated over the next week. Patient 1 reported nausea, headache, a high fever, and retrograde amnesia. Patient 2 reported visual disturbance, headache, dysarthria, a left forearm tremor, dysesthesia of the mouth and distal limbs, and visual agnosia. PCR test results for SARS-CoV-2 were negative. Complete blood cell count, biochemistry, and antibody test and cerebrospinal fluid test findings were unremarkable. Diffusion-weighted and fluid-attenuated inversion recovery MRI of the brain showed a high signal intensity lesion at the midline of the splenium of the corpus callosum compatible with cytotoxic lesions of the corpus callosum (CLOCCs). High-dose intravenous methylprednisolone improved their symptoms and imaging findings. CLOCCs should be considered in patients with neurological manifestation after COVID-19 vaccination.

Whole-body magnetic resonance imaging findings and patterns of chronic nonbacterial osteomyelitis in a series of Greek pediatric patients.

Background:Chronic nonbacterial osteomyelitis (CNO) is a pediatric autoinflammatory disorder presenting with sterile inflammatory bone lesions. Whole-body MRI (WBMRI) has most recently emerged for disease assessment, but data are limited.Purpose:The purpose is to evaluate the imaging findings and patterns of CNO on WBMRI in a series of Greek pediatric patients.Material and Methods:Whole-body magnetic resonance imaging studies of all children with documented CNO, performed in a single tertiary center, were retrospectively reviewed. WBMRI included coronal T1 and short-tau inversion recovery (STIR), whole spine sagittal STIR, and ankle/foot sagittal STIR images. High signal intensity lesions on STIR images corresponding to bone marrow edema were recorded. The SPSS v.20 statistical package was used for descriptive statistics.Results:Twenty children were included (mean age: 12, range: 6–16 years) with 1–31 lesions (mean: 11.8) on WBMRI. Two children had unifocal disease localized at the clavicle, three paucifocal (1–4 lesions), and 15 multifocal bone involvement. All but two children presented with ankle pain and exhibited lesions at the bones of the ankle joint (90%) followed by the knee (50%) and pelvis (10%). The tibia was the most frequently affected bone (70%) followed by calcaneus (60%), fibula (50%), femur (45%), talus, and metatarsals (45%). No lesions in the cervical, thoracic, lumbar spine, and mandible were documented. Only small sacral lesions were seen in 25% of patients with the extensive peripheral disease. Bilateral metaphyseal and epiphyseal involvement with transphyseal extension were common, but the periosteal reaction and well-defined lesion margins were rare.Conclusion:Frequent involvement of the foot and ankle and paucity of substantial spinal involvement were seen in Greek pediatric patients with CNO.

Atypical Multiple Sclerosis Presenting as Bilateral Optic Neuritis

Purpose: We report a case of multiple sclerosis with bilateral optic neuritis that was atypical in terms of both the clinical signs and symptoms.Case summary: A 34-year-old female visited the department of neurology with a complaint of sudden-onset, left lower extremity weakness and numbness that had developed 3 weeks prior, and bilateral blurred vision that had commenced 2 weeks prior. The patient was diagnosed with multiple sclerosis and prescribed high-dose intravenous methylprednisolone for 3 days, but the blurred vision did not improve. The patient was referred to the ophthalmology department. The initial best-corrected visual acuity was 0.04 in both eyes, and the relative afferent pupillary defect test was positive for the left eye. The Ishihara color test scores were 1/17 for both eyes. No optic disc swelling was evident on fundus examination. Brain and spine magnetic resonance imaging (T2-weighted) performed during the initial visit revealed lesions of high signal intensity in the frontal, subcortical white matter; the optic chiasm; the left retrobulbar optic segment; the medulla; and the spinal C2-5 processes. Aquaproin-4 immunogloblin G antibody (AQP4-IgG Ab) was not detected in serum. One month after prescription of the oral steroid, the vision improved to 1.0 in the right and 0.8 in the left eye. The patient was lost to follow-up after prescription of interferon-beta for 4 years, without recurrence.Conclusions: Binocular optic neuritis accompanied by severe visual loss is a rare form of multiple sclerosis. A thorough diagnosis (with a focus on exclusion) is required, as is appropriate treatment.

Squamous Cell Carcinoma Overlying Cervical Myoma

A 62-year-old woman, gravida 4, para 3, presented to the hospital with vaginal discharge and intermittent spotting for 6 months. She was identified with an asymptomatic vaginal mass 10 years ago but missed cervical cancer screening and further evaluation. Her gynecologic examination showed a 6-cm bulky vaginal mass arising from the cervix with a 4.5 × 3.5 cm ulcerative lesion. The mass was movable with clear edges, and the vagina and parametrium were not involved on palpation. Magnetic resonance imaging demonstrated a normal uterus and a myoma protruding into the vagina with a slightly high signal intensity lesion on its surface (Fig.

Plasma Interleukin-33 level in relapsing-remitting multiple sclerosis. Is it negatively correlated with central nervous system lesions in patients with mild disability?

BackgroundCytokines and chemokines are undoubtedly involved in the pathogenesis of multiple sclerosis (MS). There are many reports that suggest a significant role for Interleukin-33 (IL-33) in the course of MS development, but it is not clear whether negative or positive. We therefore investigated plasma IL-33 levels in patients with relapsing-remitting MS (RRMS). MethodsThe study consisted of RRMS patients (n = 73) and healthy subjects (n = 54). Blood samples were taken from all and plasma IL-33 levels were then determined using an enzyme-linked immunosorbent assay method. Patients also underwent laboratory and imaging tests and their disability status was assessed. ResultsPlasma IL-33 levels were marginally significantly higher in patients with RRMS (p = 0.07). Higher IL-33 levels are significantly associated with higher age (p = 0.01). There was also a statistically significant negative correlation between plasma IL-33 levels and the number of high signal intensity lesions in T2-weighted MRI (p = 0.03). After dividing the number of lesions into groups < 9 and ≥ 9 T2-weighted lesions, the Student's t-test for unrelated variables showed a negative correlation, but not statistically significant (p = 0.22), while the Spearman's correlation showed a marginally significant correlation (p = 0.06) between IL-33 level and number of T2-weighted lesions. IL-33 was also shown to have a significant ability to differentiate RRMS patients from healthy subjects with a sensitivity of 99% and specificity of 70% (p = 0.00). ConclusionsPatients with RRMS have elevated plasma IL-33 levels. In RRMS patients with mild disability, high plasma levels of IL-33 may have neuroprotective effects potentially by stimulating remyelination and/or suppressing autoimmune inflammation and damage. Further studies on this matter on a larger number of patients are needed.

Efficacy and Safety of Direct Oral Anticoagulant for Treatment of Atrial Fibrillation in Cerebral Amyloid Angiopathy

A 75-year-old man with a history of atrial fibrillation (AF) and anticoagulant therapy presented with a headache. Cerebral amyloid angiopathy (CAA) was diagnosed after MRI of the brain revealed cortical superficial siderosis, lobar intracerebral hemorrhage, and lobar microbleeds. Anticoagulant therapy was carefully discontinued. Several years later, he was admitted with sudden onset left upper-extremity weakness. In addition to CAA bleeding lesions, a diffusion-weighted brain MRI showed multiple infarct lesions of high signal intensity. The administration of edoxaban 7.5 mg/day (later increased up to 30 mg/day) prevented ischemic stroke recurrence without exacerbation of cerebral bleeding. This could indicate that CAA patients with AF who had previous adverse effects from warfarin can safely use newer direct oral anticoagulants, such as edoxaban, to prevent ischemic stroke without danger of cerebral hemorrhage. The superiority of edoxaban as compared with warfarin might be due to its antioxidant effect because vascular oxidative stress plays a causal role in CAA-induced cerebrovascular dysfunction, CAA-induced cerebral hemorrhage, and CAA formation itself. We explained the beneficial effect of edoxaban for CAA by the mechanism of oxidative stress in the paper.

Prognostication of anaplastic astrocytoma patients: application of contrast leakage information of dynamic susceptibility contrast-enhanced MRI and dynamic contrast-enhanced MRI.

To examine the applicability of contrast leakage information from dynamic susceptibility contrast-enhanced (DSC) MRI and dynamic contrast-enhanced (DCE) MRI to determine which one is the most valuable surrogate imaging biomarker for predicting disease progression in anaplastic astrocytoma (AA) patients. This study was approved by the institutional review board (IRB), which waived informed consent. A total of seventy-three AA patients who had undergone preoperative DCE and DSC MRI and received standard treatment, including partial resection or biopsy followed by radiation therapy, were included in this retrospective study. Based on Response Assessment in Neuro-Oncology (RANO), patients were sorted into progression (n = 21) and non-progression (n = 52) groups. Tumor boundaries were defined as high-signal intensity (SI) lesions on fluid-attenuated inversion recovery (FLAIR) imaging, where we analyzed mean pharmacokinetic parameters (Ktrans, Vp, and Ve) from DCE MRI and contrast leakage information (mean extraction fraction (EF)) from DSC MRI. Mean Ve and mean EF were significantly higher in patients with progression-free survival (PFS) < 18 months than in those with PFS ≥ 18 months. For distinguishing the group with PFS < 18 months, AUC values were calculated using the mean Ve value (AUC = 0.716). The Kaplan-Meier survival analysis revealed that mean Ve value was significantly correlated with PFS. In Cox proportional-hazards regression, only the mean Ve value was found to be significantly associated with PFS. We found that the mean Ve value based on high-SI tumor lesions on FLAIR imaging was capable of predicting outcomes of AA patients as a potential surrogate imaging biomarker. • Mean Ve(2.152 ± 1.857 vs. 1.173 ± 1.408) was significantly higher in anaplastic astrocytoma patients with PFS < 18 months that in those with PFS ≥ 18 months (p = 0.02). • Cox proportional-hazards regression showed that only mean Ve(p = 0.034) was significantly associated with PFS, regardless of IDH mutation status, in anaplastic astrocytoma patients.

Prognostic Value of Dynamic Contrast-Enhanced MRI-Derived Pharmacokinetic Variables in Glioblastoma Patients: Analysis of Contrast-Enhancing Lesions and Non-Enhancing T2 High-Signal Intensity Lesions.

ObjectiveTo evaluate pharmacokinetic variables from contrast-enhancing lesions (CELs) and non-enhancing T2 high signal intensity lesions (NE-T2HSILs) on dynamic contrast-enhanced (DCE) magnetic resonance (MR) imaging for predicting progression-free survival (PFS) in glioblastoma (GBM) patients.Materials and MethodsSixty-four GBM patients who had undergone preoperative DCE MR imaging and received standard treatment were retrospectively included. We analyzed the pharmacokinetic variables of the volume transfer constant (Ktrans) and volume fraction of extravascular extracellular space within the CEL and NE-T2HSIL of the entire tumor. Univariate and multivariate Cox regression analyses were performed using preoperative clinical characteristics, pharmacokinetic variables of DCE MR imaging, and postoperative molecular biomarkers to predict PFS.ResultsThe increased mean Ktrans of the CEL, increased 95th percentile Ktrans of the CELs, and absence of methylated O6-methylguanine-DNA methyltransferase promoter were relevant adverse variables for PFS in the univariate analysis (p = 0.041, p = 0.032, and p = 0.083, respectively). The Kaplan-Meier survival curves demonstrated that PFS was significantly shorter in patients with a mean Ktrans of the CEL > 0.068 and 95th percentile Ktrans of the CEL>0.223 (log-rank p = 0.038 and p = 0.041, respectively). However, only mean Ktrans of the CEL was significantly associated with PFS (p = 0.024; hazard ratio, 553.08; 95% confidence interval, 2.27–134756.74) in the multivariate Cox proportional hazard analysis. None of the pharmacokinetic variables from NE-T2HSILs were significantly related to PFS.ConclusionAmong the pharmacokinetic variables extracted from CELs and NE-T2HSILs on preoperative DCE MR imaging, the mean Ktrans of CELs exhibits potential as a useful imaging predictor of PFS in GBM patients.

Focal hyperemia in Wernicke's encephalopathy: a preliminary arterial spin labeling MRI study.

Although a perturbed cerebral blood flow (CBF) has been reported in patients with Wernicke's encephalopathy (WE), its clinical meaning is still elusive. A retrospective analysis of 10 patients (male, 6; mean age, 57.7 years) with WE between October 2012 and May 2018 was performed. Brain imaging was performed using fluid-attenuated inversion recovery (FLAIR), diffusion-weighted imaging (DWI), arterial spin labeling (ASL) perfusion-weighted imaging (PWI), and contrasted enhanced T1-weighted imaging. All patients had symmetric high signal intensity lesions in the vulnerable areas on FLAIR or DWI with focal hyperintensity on ASL-PWI (100% sensitivity). CBFlesion was variable (from 70 mL/100 g/min to 190.0 mL/100 g/min). CBFlesion/CBFwhite matter was elevated, ranging from 2.5 to 5.5. Focal hyperintensity on ASL in the vulnerable areas can be a diagnostic clue for WE.

Optimizing 3D FLAIR to detect MS lesions: pushing past factory settings for precise results.

To assess the diagnostic value of three 3D FLAIR sequences with differing repetition-times (TR) at 3-Tesla when detecting multiple sclerosis (MS) lesions. In this prospective study, approved by the institutional review board, 27 patients with confirmed MS were prospectively included. One radiologist performed manual segmentations of all high-signal intensity lesions using three 3D FLAIR data sets with different TR of 4800ms ("FLAIR4800"), 8000ms ("FLAIR8000") and 10,000ms ("FLAIR10,000") and two radiologists double-checked it. The main judgment criterion was the overall number of lesions; secondary objectives were the assessment of lesion location, as well as measuring contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR). A non-parametric Wilcoxon's test was used to compare the differing FLAIR. The FLAIR8000 and FLAIR10,000 detected significantly more overall lesions per patient as compared with the FLAIR4800 [116.1 (± 61.7) (p = 0.02) and 115.8 (± 56.3) (p = 0.03) versus 99.2 (± 66.9), respectively]. The FLAIR8000 and FLAIR10,000 detected four and eight times more cortical or juxta-cortical lesions per patient as compared with FLAIR4800 [1.6 (± 2.2) (p = 0.001) and 4.1 (± 5.9) (p = 6×10-5) versus 0.4 (± 1.1), respectively]. CNR was significantly correlated to the TR value. It was significantly higher with FLAIR10,000 than it was with FLAIR8000 and FLAIR4800 [16.3 (± 3.5) versus 15 (± 2.4) (p = 0.01) and 12 (± 2.2) (p = 2×10-6), respectively] CONCLUSION: An optimized 3D FLAIR with a long TR significantly improved both overall lesion detection and CNR in MS patients as compared to a 3D FLAIR with factory settings.

Transverse Myelitis Caused by Varicella Zoster Virus

Introduction The varicella zoster virus (VZV) infection causes chickenpox and herpes zoster. Primary infection occurs more frequently in the pediatric age as chickenpox. Virus can be latent in cranial nerve or dorsal root ganglia and reactivate several decades later as the form of herpes zoster generally in immunosuppressed patients. Varicella zoster virus is associated with severe neurological complications, including post herpetic neuralgia, aseptic meningitis, polyneuropathy, cranial nerve palsy, meningoencephalitis, vasculopathy, encephalitis, and transverse myelitis. The transverse myelitis caused by VZV is reported rarely. Case Report A 77-year-old immunocompetent patient presented with muscle weakness and sensation loss due to the demyelinating lesion caused by VZV on C5 dermatome. Proprioception and vibratory sensation loss were also marked. Cervical spinal magnetic resonance imaging showed expansive intramedullary high-signal intensity lesion on C5 with focal swelling on T2-weighted images and gadalinium enhancement on T1-weighted images. cerebrospinal fluid viral antibody test was positive for immunoglobulin G of VZV but negative for VZV DNA. The patient was treated with oral valacyclovir (1 g) 3 times daily for 7 days and with methylprednisolone (1.0 g) every day for 5 days. After treatment, his muscle strength increased but sensorial loss and neuropathic pain did not recover. Conclusions About 40% of transverse myelitis cases are caused by viral infections, some of them are herpes viruses and poliovirus. Varicella zoster infection is a common disease but not a common cause of transverse myelitis particularly in immuncompetent patients. The clinicians must be aware of this rare complication of VZV.

Reader response: Teaching Video NeuroImages: Pulsatile proptosis and wall-eyed bilateral internuclear ophthalmoplegia.

We read with interest the Papageorgiou et al.1 Teaching Video NeuroImage on pulsatile proptosis and wall-eyed bilateral internuclear ophthalmoplegia. While this is a well-written case report with a good quality video, we offer an alternative interpretation of the MRI findings. At the pontine level, the medial longitudinal fasciculus (MLF) is situated beneath the floor of the fourth ventricle on either side of the midline,2 and lesions involving bilateral MLFs can cause wall-eyed bilateral internuclear ophthalmoplegia (WEBINO).3 However, the lesion that the authors indicated with the arrow on the T2-weighted MRI (figure, white arrow)1 is located more anteriorly compared to the area of the MLF on MRIs in previous reports3 and on anatomic templates.2 In addition, the lesion indicated appears chronic given the strong high signal intensity, similar to that of the CSF, even though the interval from the symptom onset to MRI was not provided. Instead, we propose that the symmetric high signal intensity lesions just beneath the facial colliculi were responsible for WEBINO in this patient (figure, black arrow added).

Editors' note: Teaching Video NeuroImages: Pulsatile proptosis and wall-eyed bilateral internuclear ophthalmoplegia

Commenting on “Teaching Video NeuroImages: Pulsatile proptosis and wall-eyed bilateral internuclear ophthalmoplegia,” Lee et al. offer an alternative interpretation of the MRI findings. They explain that the lesion suggested by the authors is chronic in nature and too anterior in the pons. They propose that the more likely explanation for the patient's wall-eyed bilateral internuclear ophthalmoplegia is the symmetric high-signal intensity lesions just beneath the facial colliculi. Authors Papageorgiou et al. reviewed the diffusion-weighted MRI of their patient and found that it showed a focal area of restricted diffusion at the midline of the pontine tegmentum beneath the floor of the fourth ventricle, which involves the medial longitudinal fasciculus bilaterally as correctly suggested by Lee et al. A correction appears on page 900. Commenting on “Teaching Video NeuroImages: Pulsatile proptosis and wall-eyed bilateral internuclear ophthalmoplegia,” Lee et al. offer an alternative interpretation of the MRI findings. They explain that the lesion suggested by the authors is chronic in nature and too anterior in the pons.

Clinical Outcomes and Prognostic Factors in Patients With Myelopathy Caused by Thoracic Ossification of the Ligamentum Flavum

ObjectiveThe objective of this study was to investigate the surgical outcomes and prognostic factors for thoracic ossification of the ligamentum flavum (OLF) after decompressive laminectomy, focusing on the quantitative signal intensity ratio (SIR) of preoperative magnetic resonance imaging (MRI) and its prognostic significance. MethodsWe retrospectively reviewed 24 patients who previously underwent total laminectomy to remove OLF from 2010 to 2015. MRI and computed tomography were performed to detect OLF. The SIR between the regions of interest of high signal intensity lesions and the normal cord at the T1–2 disc levels was calculated. We divided patients into 2 groups based on the extent of the modified Japanese Orthopaedic Association (JOA) recovery rate (RR): good (RR ≥ 50%) and poor (RR < 50%). ResultsThe mean preoperative and postoperative modified JOA scores for thoracic myelopathy were 6.67 ± 1.73 and 8.63 ± 1.81, respectively (p < 0.001). The preoperative JOA score (7.5 vs. 5.83, p = 0.028), postoperative JOA score (9.83 vs. 7.42, p = 0.000), and SIR (1.16 vs. 1.41, p = 0.009) were significantly different between the good and poor RR groups. A higher preoperative JOA score and lower SIR were associated with a good RR according to the JOA criteria. ConclusionThe clinical outcomes for thoracic OLF after decompressive laminectomy were favorable. A higher RR was correlated with a lower SIR and higher preoperative modified JOA score. Therefore, a relatively low SIR on MRI and a relatively high preoperative JOA score could be positive prognostic indicators for the JOA RR in patients with thoracic OLF.

Threshold of the extent of resection for WHO Grade III gliomas: retrospective volumetric analysis of 122 cases using intraoperative MRI.

OBJECTIVE WHO Grade III gliomas are relatively rare and treated with multiple modalities such as surgery, chemotherapy, and radiotherapy. The impact of the extent of resection (EOR) on improving survival in patients with this tumor type is unclear. Moreover, because of the heterogeneous radiological appearance of Grade III gliomas, the MRI sequence that best correlates with tumor volume is unknown. In the present retrospective study, the authors evaluated the prognostic significance of EOR. METHODS Clinical and radiological data from 122 patients with newly diagnosed WHO Grade III gliomas who had undergone intraoperative MRI-guided resection at a single institution between March 2000 and December 2011 were analyzed retrospectively. Patients were divided into 2 groups by histological subtype: 81 patients had anaplastic astrocytoma (AA) or anaplastic oligoastrocytoma (AOA), and 41 patients had anaplastic oligodendroglioma (AO). EOR was calculated using pre- and postoperative T2-weighted and contrast-enhanced T1-weighted MR images. Univariate and multivariate analyses were performed to evaluate the prognostic significance of EOR on overall survival (OS). RESULTS The 5-, 8-, and 10-year OS rates for all patients were 74.28%, 70.59%, and 65.88%, respectively. The 5- and 8-year OS rates for patients with AA and AOA were 72.2% and 67.2%, respectively, and the 10-year OS rate was 62.0%. On the other hand, the 5- and 8-year OS rates for patients with AO were 79.0% and 79.0%; the 10-year OS rate is not yet available. The median pre- and postoperative T2-weighted high-signal intensity volumes were 56.1 cm3 (range 1.3-268 cm3) and 5.9 cm3 (range 0-180 cm3), respectively. The median EOR of T2-weighted high-signal intensity lesions (T2-EOR) and contrast-enhanced T1-weighted lesions were 88.8% (range 0.3%-100%) and 100% (range 34.0%-100%), respectively. A significant survival advantage was associated with resection of 53% or more of the preoperative T2-weighted high-signal intensity volume in patients with AA and AOA, but not in patients with AO. Univariate analysis showed that preoperative Karnofsky Performance Scale score (p = 0.0019), isocitrate dehydrogenase 1 ( IDH1) mutation (p = 0.0008), and T2-EOR (p = 0.0208) were significant prognostic factors for survival in patients with AA and AOA. Multivariate analysis demonstrated that T2-EOR (HR 3.28; 95% CI 1.22-8.81; p = 0.0192) and IDH1 mutation (HR 3.90; 95% CI 1.53-10.75; p = 0.0044) were predictive of survival in patients with AA and AOA. CONCLUSIONS T2-EOR was one of the most important prognostic factors for patients with AA and AOA. A significant survival advantage was associated with resection of 53% or more of the preoperative T2-weighted high-signal intensity volume in patients with AA and AOA.

Localized reversible high signal intensities on diffusion-weighted MRI in hypoglycemia: A study of 70 cases

Introduction:It is well-known that localized reversible high signal intensities in the splenium of the corpus callosum or the basal ganglia appear on diffusion-weighted MRI in the presence of hypoglycemia. The aim of this study was to clarify the incidence and significance of such high signal intensity lesions.Results:We analyzed 70 cases of hypoglycemia with consciousness disturbance referred to our outpatient office. Localized reversible high signal intensities on diffusion-weighted MRI were noted in 6 cases (8.6%). They were at the splenium of the corpus callosum in four cases (5.7%), and right frontal cortex and bilateral frontal white matter in one each. Convulsions were noted in five cases, and right hemiparesis was noted in three. None of the three cases of hemiparesis showed localized reversible high signal intensities on diffusion-weighted MRI. These lesions are reversible if the patients undergo treatment without delay.Conclusion:The significance of these lesions is still unclear. However, when a high signal intensity lesion that is not reasonable for the symptom is detected on diffusion-weighted MRI, an immediate check of the blood sugar level is mandatory.