The Brain Tumor Segmentation (BraTS-METS) Challenge 2023: Brain Metastasis Segmentation on Pre-treatment MRI.

Clinical monitoring of metastatic disease to the brain can be a laborious and timeconsuming process, especially in cases involving multiple metastases when the assessment is performed manually. The Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) guideline, which utilizes the unidimensional longest diameter, is commonly used in clinical and research settings to evaluate response to therapy in patients with brain metastases. However, accurate volumetric assessment of the lesion and surrounding peri-lesional edema holds significant importance in clinical decision-making and can greatly enhance outcome prediction. The unique challenge in performing segmentations of brain metastases lies in their common occurrence as small lesions. Detection and segmentation of lesions that are smaller than 10 mm in size has not demonstrated high accuracy in prior publications. The brain metastases challenge sets itself apart from previously conducted MICCAI challenges on glioma segmentation due to the significant variability in lesion size. Unlike gliomas, which tend to be larger on presentation scans, brain metastases exhibit a wide range of sizes and tend to include small lesions. We hope that the BraTS-METS dataset and challenge will advance the field of automated brain metastasis detection and segmentation.

Transient in-stent stenosis at mid-term angiographic follow-up in patients treated with SILK flow diverter stents: incidence, clinical significance and long-term follow-up.

BACKGROUND: Little is known about in-stent stenosis (ISS) in patients with aneurysms treated with flow diverter (FD) stents. The reported incidence in the literature varies significantly. OBJECTIVE: The aim of this study was to assess the incidence, severity, distribution, clinical significance, and possible predictors for ISS. METHODS: Between July 2012 and June 2016 we retrospectively reviewed all patients treated with SILK FDs in our center. Only cases with short-term (4±2 months) and long-term (>1 year) follow-ups with digital subtraction angiograms were included. ISS was graded as mild (<25%), moderate (25-50%) or severe (>50%). The following predictors for ISS were assessed: gender, age, the presence of subarachnoid hemorrhage, aneurysm size, location, occlusion status, and post-stenting angioplasty. RESULTS: Thirty-six patients met the inclusion criteria. At mid-term follow-up, ISS was observed in 16/36 patients (44%). Eleven patients (69%) had mild ISS, three (19%) moderate, and two (12%) severe ISS. ISS was diffuse in 11 patients (69%) and focal in five patients (31%). All patients were asymptomatic. Thirteen patients were maintained on dual antiplatelet therapy and three on aspirin alone. At long-term follow-up, complete ISS resolution was seen in 11 patients, improvement in three and worsening in two patients. No de novo ISS occurrence was observed. On univariate analysis there was no significant predictor for ISS. CONCLUSIONS: Transient ISS after FD deployment is a common asymptomatic finding on mid-term angiographic follow-up. Complete resolution or improvement at long-term follow-up is seen in most patients who are maintained on dual antiplatelet therapy.

Endovascular glue embolization of a radiation-induced lenticulostriate artery pseudoaneurysm in a pediatric patient with optic pathway glioma: Case report and review of literature.

Radiation-associated vascular changes most commonly present in the form of stenosis, thrombosis and occlusion. However, development of intracranial aneurysms secondary to radiation is far less common and often manifests with rupture. These aneurysms are difficult to treat and associated with high morbidity and mortality when ruptured compared with saccular aneurysms unrelated to radiation treatment. Both surgical and endovascular options are available for treatment of these aneurysms. We present a young patient with a radiation-induced intracranial pseudoaneurysm arising from the lenticulostriate branch of the left middle cerebral artery (MCA); this developed 1 year 4 months after 59.4 Gy of focused radiation to the suprasellar pilomyxoid astrocytoma. The patient successfully underwent endovascular glue embolization of the aneurysm and occlusion of the lenticulostriate artery after unsuccessful trapping of the aneurysm and occlusion of the parent artery using coils. She developed transient hemiparesis of the right side following the procedure, which was managed conservatively. We performed a complete review of the literature dealing with the radiation-induced intracranial aneurysms, their presentation, treatment and outcome.

Extracranial Venous abnormalities: A true pathological finding in patients with multiple sclerosis or an anatomical variant?

OBJECTIVE: To evaluate the extracranial venous anatomy with contrast-enhanced MR venogram (CE-MRV) in patients without multiple sclerosis (MS), and assess the prevalence of various venous anomalies such as asymmetry and stenosis in this population. MATERIALS AND METHODS: We prospectively recruited 100 patients without MS, aged 18-60 years, referred for contrast-enhanced MRI. They underwent additional CE-MRV from skull base to mediastinum on a 3T scanner. Exclusion criteria included prior neck radiation, neck surgery, neck/mediastinal masses or significant cardiac or pulmonary disease. Two neuroradiologists independently evaluated the studies to document asymmetry and stenosis in the jugular veins and prominence of collateral veins. RESULTS: Asymmetry of internal jugular veins (IJVs) was found in 75 % of subjects. Both observers found stenosis in the IJVs with fair agreement. Most stenoses were located in the upper IJV segments. Asymmetrical vertebral veins and prominence of extracranial collateral veins, in particular the external jugular veins, was not uncommon. CONCLUSION: It is common to have stenoses and asymmetry of the IJVs as well as prominence of the collateral veins of the neck in patients without MS. These findings are in contrast to prior reports suggesting collateral venous drainage is rare except in MS patients. KEY POINTS: • The venous anatomy of the neck in patients without MS demonstrates multiple variants • Asymmetry and stenoses of the internal jugular veins are common • Collateral neck veins are not uncommon in patients without MS • These findings do not support the theory of chronic cerebrospinal venous insufficiency • MR venography is a useful imaging modality for assessing venous anatomy.

Canadian Registry of LVIS Jr for Treatment of Intracranial Aneurysms (CaRLA).

INTRODUCTION: Stents reduce the rate of angiographic recurrence of intracranial aneurysms. The newest stent for intracranial use is the Low-profile Visible Intraluminal Support device (LVIS Jr). OBJECTIVE: To assess the efficacy of the new stent in a multicenter retrospective registry. MATERIALS AND METHOD: Centers across Canada using LVIS Jr were contacted and asked to participate in a retrospective registry of consecutive patients treated with LVIS Jr for intracranial aneurysms between January 2013 and July 2015. RESULTS: A total of 102 patients, with saccular aneurysms in 100 patients (72 women; age range 21-78 years; mean 56.0 years; median 57.5 years) were treated with a LVIS Jr stent. The mean maximum diameter of the dome and neck of the aneurysm and dome to neck ratios were 8.3 mm±7.7 mm, 4.4 mm±1.9 mm, and 1.86±1.22, respectively. Angiographic complications arose in 23 patients, clinical complications in 9 patients, and only 3% of permanent neurological deficits occurred. Death occurred in 1 patient, unrelated to the stent. The ruptured status of the aneurysms (OR=3.29; p=0.046) and use of LVIS Jr for bailout (OR=2.54; p=0.053) showed a trend towards significant association with higher angiographic complications. At the last available follow-up, 68 class I, 20 class II, and 12 class III results were seen. CONCLUSIONS: The LVIS Jr stent is a safe and effective device for stent-assisted coiling, with 3% permanent neurological complications. Stent-assisted coiling continues to be technically challenging in cases of ruptured aneurysms and bailout situations.

The use of adaptive statistical iterative reconstruction (ASiR) technique in evaluation of patients with cervical spine trauma: impact on radiation dose reduction and image quality.

OBJECTIVE: The aim of this study was to evaluate the impact of adaptive statistical iterative reconstruction (ASiR) technique on the image quality and radiation dose reduction. The comparison was made with the traditional filtered back projection (FBP) technique. METHODS: We retrospectively reviewed 78 patients, who underwent cervical spine CT for blunt cervical trauma between 1 June 2010 and 30 November 2010. 48 patients were imaged using traditional FBP technique and the remaining 30 patients were imaged using the ASiR technique. The patient demographics, radiation dose, objective image signal and noise were recorded; while subjective noise, sharpness, diagnostic acceptability and artefacts were graded by two radiologists blinded to the techniques. RESULTS: We found that the ASiR technique was able to reduce the volume CT dose index, dose-length product and effective dose by 36%, 36.5% and 36.5%, respectively, compared with the FBP technique. There was no significant difference in the image noise (p = 0.39), signal (p = 0.82) and signal-to-noise ratio (p = 0.56) between the groups. The subjective image quality was minimally better in the ASiR group but not statistically significant. There was excellent interobserver agreement on the subjective image quality and diagnostic acceptability for both groups. CONCLUSION: The use of ASiR technique allowed approximately 36% radiation dose reduction in the evaluation of cervical spine without degrading the image quality. ADVANCES IN KNOWLEDGE: The present study highlights that the ASiR technique is extremely helpful in reducing the patient radiation exposure while maintaining the image quality. It is highly recommended to utilize this novel technique in CT imaging of different body regions.

Role of neuroimaging in multidisciplinary approach towards Non-Alzheimer's dementia.

Dementia is defined as chronic deterioration of intellectual function and cognitive skills significant enough to interfere with the ability to perform daily activities. Recent advances in the treatment of dementia have renewed interest in the use of various neuroimaging techniques that can assist in the diagnosis and differentiation of various subtypes. Neuroimaging and computational techniques have helped the radiological community to monitor disease progression of various neurodegenerative conditions presenting with dementia, such as Alzheimer disease, frontotemporal lobe dementia (FTLD), progressive supranuclear palsy (PSP) and multisystem atrophy-cerebellar variant (MSA-C), and their response to newer therapies. Prompt identification of treatable or reversible forms of dementia, such as tumours, subdural haemorrhage and intracranial dAVF, is crucial for the effective management of these conditions. It is also prudent to recognize the imaging spectrum of metabolic, infective and autoimmune diseases with rapidly progressing dementia, such as methanol toxicity, central pontine myelinolysis (CPM), delayed post hypoxic leukoencephalopathy (DPHL), HIV, Creutzfeldt-Jakob Disease (CJD), Sjogren's syndrome, multiple sclerosis (MS), radiation necrosis and Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS), which are difficult to treat and often require palliative care. This pictorial review emphasizes various non-Alzheimer's dementia entities and discusses their imaging highlights. Teaching Points • Non Alzheimer's dementia constitutes a broad spectrum of conditions. • Neuroimaging plays an important role in differentiating treatable from irreversible dementia. • Neuroimaging is often non-specific in early stages of neurodegenerative conditions with dementia. • Neuroimaging plays an important role in the multimodal approach towards management of dementia.

An unusual case of isolated hypoglossal nerve palsy secondary to osteophytic projection from the atlanto-occipital joint.

We describe an unusual and rare case of isolated left hypoglossal nerve palsy secondary to compression from a prominent degenerative osteophyte from the left atlanto-occipital joint. The hypoglossal nerve is a purely motor cranial nerve innervating the tongue musculature. Palsy of the hypoglossal nerve is frequently associated with other cranial nerve palsies and can be related to vascular, neoplastic, infectious or traumatic conditions. Isolated hypoglossal nerve palsy is quite rare and very few cases have been reported in the literature to date.

The efficacy of transforaminal epidural steroid injections in lumbosacral radiculopathy.

BACKGROUND: Transformational epidural steroid (TFES) is commonly used to treat lumbosacral radicular pain. However, very few studies have systematically evaluated the quality of analgesia following such procedures with respect to time. OBJECTIVE: To evaluate long-term efficacy of TFES in patients with lumbosacral radiculopathy. MATERIALS AND METHODS: A prospective study including 30 patients having lumbosacral radiculopathy secondary to prolapsed disc. Outcome variables were the amount of improvement just after the procedure and thereafter at 24 hrs, 1 month, 6 month and 1 year post-procedure, respectively, using visual analog scale (VAS) and numeric rating scale (NRS). Patients also filled Roland-Morris questionnaire pre-procedure, 6 month and 1 year follow-up. All patients received Ibuprofen for 3 days following the procedure, to alleviate post- procedural pain. An option of rescue surgery was reserved in case of unbearable pain (>7 VAS), appearance of sudden motor deficit or if patient opts for surgery. Same injection was repeated if at any point of time pain had >5 in VAS. RESULTS: As per NRS, almost all patients had complete pain relief (mean 98%) immediate postprocedure. At 24 hrs, the score was 79%, at 1 month 60%, at 6 months 58.5% and at 1 year 59%. Preprocedure VAS was 9.2 and thereafter 0.6, 1.8, 3.9, 3.8 and 4.2 at similar time points. Roland-Morris score was 18/24, 10/24, 9/24, at pre-procedure, at 6 months and at 1 year, respectively. No complication was noted in any patient except post procedural local pain. CONCLUSION: Quality of pain relief produced by TFES was significant. Long-term quality of pain relief was better in patients with pain duration less than 6 months. Even though, the study was designed to inject the drug once, many of the patients required second injection. A further study with multiple injections at prefixed time interval might probably result in a better overall outcome.

Can diffusion tensor metrics help in preoperative grading of diffusely infiltrating astrocytomas? A retrospective study of 36 cases.

INTRODUCTION: Diffusion weighted imaging and diffusion tensor imaging (DTI) give information about the amount and directionality of water diffusion occurring in a given tissue. Here we study the role of diffusion tensor metrics including fractional anisotropy (FA) and spherical anisotropy (CS) in preoperative grading of diffusely infiltrating astrocytomas. METHODS: We performed DTI in 38 patients with pathologically proven diffusely infiltrating astrocytomas, who were classified into two groups, i.e., 15 patients with high-grade astrocytoma (HGAs, WHO grade III and IV) and 23 patients with low-grade astrocytoma (LGAs, WHO grade II). We measured maximum FA and minimum CS values in all cases from tumor. Histopathological diagnosis was established in all cases. RESULTS: The mean maximum FA values were higher in HGA (0.583 ± 0.104) than LGA (0.295 ± 0.058), while mean minimum CS values were lower in HGA (0.42 ± 0.121) than LGA (0.722 ± 0.061). The difference in the diffusion tensor indices between HGA and LGA was found to be statistically significant with P value of <0.001. Keeping cutoff FA value of 0.4, all HGAs showed higher maximum FA values, and all LGAs showed lower maximum FA values. Also, all HGAs showed minimum CS values less than a cutoff value of 0.6, and all LGAs showed minimum CS values higher than 0.6. CONCLUSION: Diffusion tensor metrics such as maximum FA and minimum CS can help to differentiate HGA from LGA.

Combined transarterial and percutaneous coiling of a spontaneous vertebrovertebral fistula associated with neurofibromatosis Type 1. Case report.

The authors report a rare case of spontaneous left vertebrovertebral fistula associated with neurofibromatosis Type 1 in a young woman. The patient had undergone previous failed surgical attempts to close the fistula and presented to the authors with recurrence of the fistula and neurological deterioration. Successful obliteration of the fistula with combined transarterial and percutaneous coiling with Guglielmi detachable coils resulted in disappearance of the fistula and significant neurological improvement.

Diffusion tensor mode in imaging of intracranial epidermoid cysts: one step ahead of fractional anisotropy.

INTRODUCTION: The signal characteristics of an epidermoid on T2-weighted imaging have been attributed to the presence of increased water content within the tumor. In this study, we explore the utility of diffusion tensor imaging (DTI) and diffusion tensor metrics (DTM) in knowing the microstructural anatomy of epidermoid cysts. MATERIALS AND METHODS: DTI was performed in ten patients with epidermoid cysts. Directionally averaged mean diffusivity (D(av)), exponential diffusion, and DTM-like fractional anisotropy (FA), diffusion tensor mode (mode), linear (CL), planar (CP), and spherical (CS) anisotropy were measured from the tumor as well as from the normal-looking white matter. RESULTS: Epidermoid cysts showed high FA. However, D(av) and exponential diffusion values did not show any restriction of diffusion. Diffusion tensor mode values were near -1, and CP values were high within the tumor. This suggested preferential diffusion of water molecules along a two-dimensional geometry (plane) in epidermoid cysts, which could be attributed to the parallel-layered arrangement of keratin filaments and flakes within these tumors. CONCLUSION: Thus, advanced imaging modalities like DTI with DTM can provide information regarding the microstructural anatomy of the epidermoid cysts.