AJNR. American journal of neuroradiology最新文献

Background and purpose: Spontaneous intracranial hypotension (SIH) due to CSF venous fistula (CVF) is increasingly recognized as a secondary cause of headaches, with symptoms often overlapping with primary headache syndromes such as migraine. While brain MRI studies have focused on features indicative of SIH, findings that support an alternate headache etiology, such as the bifrontal white matter hyperintensities (WMH) often seen in migraines, have not been explored in this context. This study assesses 1) the quantity and distribution of WMH and 2) the presenting clinical features in patients with and without CVF found on dynamic decubitus CT myelography (dCTM).

Materials and methods: 72 consecutive patients underwent clinical workup for SIH due to suspected CVF, including pre-procedural brain and spine MRI followed by dCTM. Brain imaging features were analyzed, including Bern score, quantitative WMH burden, and WMH distribution. Demographics and clinical symptoms present at the time of presentation were recorded. Imaging features were compared between groups with and without CVF using parametric or nonparametric comparisons according to variable normality. Multivariate logistic regression explored the relationships between imaging features, clinical symptoms, and the presence of CVF.

Results: The cohort included 40 patients with (CVF+) and 32 patients without (CVF-), with no significant age or sex differences. CVF+ patients had significantly higher Bern scores and significantly fewer WMH. There were significant differences in the frequencies of WMH patterns between groups, with a migrainous pattern observed most frequently in CVF-patients. Logistic regression combining Bern score, WMH burden, and WMH pattern demonstrated a better fit for predicting CVF than using Bern score or WMH features alone. Fourteen clinical symptoms showed the greatest differences between CVF+ and CVF-groups. Logistic regression demonstrated a positive association between CVF detection and a pressure/throbbing headache quality, and negative associations for neck pain, facial pain, phonophobia, and anhedonia/depression.

Conclusions: These findings suggest a negative association between CVF detection, increased burden of WMH, and a migrainous WMH pattern. Symptom analysis describes distinct clinical phenotypes, challenging orthostatic headache as a defining characteristic. These results support a comprehensive assessment of imaging and clinical presentations in the workup of suspected SIH.

Abbreviations: SIH = spontaneous intracranial hypotension; CVF = CSF venous fistula; WMH = white matter hyperintensities; dCTM = dynamic CT myelography; dDSM = dynamic digital subtraction myelography; PPV = positive predictive value; NPV = negative predictive value Received month day, year; accepted after revision month day, year.

Background and purpose: Recent advances in deep learning have shown promising results in medical image analysis and segmentation. However, most brain MRI segmentation models are limited by the size of their datasets and/or the number of structures they can identify. This study evaluates the performance of six advanced deep learning models in segmenting 122 brain structures from T1-weighted MRI scans, aiming to identify the most effective model for clinical and research applications.

Materials and methods: 1,510 T1-weighted MRIs were used to compare six deep-learning models for the segmentation of 122 distinct gray matter structures: nnU-Net, SegResNet, SwinUNETR, UNETR, U-Mamba_BOT and U-Mamba_ Enc. Each model was rigorously tested for accuracy using the Dice Similarity Coefficient (DSC) and the 95th percentile Hausdorff Distance (HD95). Additionally, the volume of each structure was calculated and compared between normal control (NC) and Alzheimer's Disease (AD) patients.

Results: U-Mamba_Bot achieved the highest performance with a median DSC of 0.9112 [IQR:0.8957, 0.9250]. nnU-Net achieved a median DSC of 0.9027 [IQR: 0.8847, 0.9205] and had the highest HD95 of 1.392[IQR: 1.174, 2.029]. The value of each HD95 (<3mm) indicates its superior capability in capturing detailed brain structures accurately. Following segmentation, volume calculations were performed, and the resultant volumes of normal controls and AD patients were compared. The volume changes observed in thirteen brain substructures were all consistent with those reported in existing literature, reinforcing the reliability of the segmentation outputs.

Conclusions: This study underscores the efficacy of U-Mamba_Bot as a robust tool for detailed brain structure segmentation in T1-weighted MRI scans. The congruence of our volumetric analysis with the literature further validates the potential of advanced deep-learning models to enhance the understanding of neurodegenerative diseases such as AD. Future research should consider larger datasets to validate these findings further and explore the applicability of these models in other neurological conditions.

Abbreviations: AD = Alzheimer's Disease; ADNI = Alzheimer's Disease Neuroimaging Initiative; DSC = Dice Similarity Coefficient; HD95 = the 95th Percentile Hausdorff Distance; IQR = Interquartile Range; NC = Normal Control; SSMs = State-space Sequence Models.

The Canadian Cervical Spine Rule, a clinical decision-making tool for patients post-trauma is often interpreted as recommending cervical spine computed tomography in patients ≥ 65 years old, who sustain a dangerous mechanism of injury, and/or have extremity paresthesias. We retrospectively reviewed 6 years' of emergency department cervical spine computed tomography reports to determine fracture rates in patients ≥ 65, symptomatic or not, who did and did not have a dangerous mechanism. Of those ≥ 65 years old, 240/13925 (1.72%) patients had cervical spine fractures. The fracture rate in asymptomatic patients ≥ 65 was 0.27%. The fracture rate in asymptomatic patients ≥ 65, who did not have a dangerous mechanism of injury was 0.15%. The rate of unstable fractures requiring surgery was 0.007%. The findings suggest that the algorithm to scan asymptomatic patients ≥ 65, and/or those ≥ 65 without a dangerous injury mechanism, should be revisited for appropriateness and overall value.ABBREVIATIONS: CCR = The Canadian Cervical Spine Rule; CSCT = cervical spine computed tomography; ED = emergency department; EMR = electronic medical record; MVC = motor vehicle collision.

Background and purpose: Low back pain commonly causes disability, often managed with conservative image-guided interventions before surgery. Research has documented racial disparities with these and other non-pharmacologic treatments. We posited that individual chart reviews may provide insight into the disparity of care types through documented patient/provider discussions and their effect on treatment plans.

Materials and methods: This retrospective analysis involved adults newly diagnosed with low back pain within a large Utah healthcare system. The primary outcome was the association of provider and patient variables with the frequency of image-guided interventions received within one year of low back pain diagnosis between White/non-Hispanic and underrepresented minority cohorts. Secondary outcomes were receipt of additional treatment types (physical therapy and lumbar surgery), time to any treatment, time to image-guided intervention, and discussion/receipt of therapy between cohorts within one year of diagnosis.

Results: Among 812 subjects (41% underrepresented minority and 59% White/non-Hispanic), more White/non-Hispanic patients had at least one image-guided intervention within 12 months compared to underrepresented minority patients (7.2% vs. 12.5%, p = .001), despite underrepresented minorities having higher presenting pain scores (64.5% vs. 49.3%; pain intensity > 5, p = .001). Underrepresented minority patients more often saw generalists (71.7% vs. 52.6%, p < .001) and advanced practice clinician providers (33.6% vs. 25.6%, p < .02) compared to the White/non-Hispanic cohort. Both cohorts were referred to a specialist at the same rate (17.7% vs. 19.8%, p = .20); however, referral completion was noted less often (60.4% vs. 77.7%, p = .02) and took longer to complete in underrepresented minority patients (54 vs. 27.5; mean day, p = .003).

Conclusions: Underrepresented minority patients had more severe low back pain on presentation but received image-guided interventions less often than White/non-Hispanic patients. Our in-depth chart analysis supports the lack of referral completion and evaluation from a spine specialist provider as the main deterrent to the receipt of image-guided interventions in this cohort. While there may be systematic provider barriers, such as absence of a decision-making discussion, data do not support provider bias as a contributing factor to differences in receipt of image-guided interventions.

Abbreviations: IGI = image-guided intervention; LBP = low back pain; URM = underrepresented minority; WNH = White/non-Hispanic; ICC = intraclass correlation coefficient.

Background and purpose: Efficacy of tumor embolization for posterior fossa meningioma is controversial due to the lack of adequate embolization for dangerous feeders. Of these, a meningohypophyseal trunk (MHT) has high therapeutic value despite the high risks associated with embolization.

Materials and methods: To analyze the utility of preoperative MHT embolization for posterior fossa meningiomas using n-BCA with dual balloon protection, a single center retrospective record review was performed on eight consecutive patients who underwent preoperative tumor embolization via the MHT for posterior fossa meningiomas between 2020 and 2024.

Results: All patients successfully embolized the MHT using n-BCA. Complete obliteration was achieved in five cases, which is related to the tentorial artery alone as the feeding vessel. None of the patients had cerebral infarction associated with distal embolization. One patient experienced worsening of preoperatively observed abducens nerve palsy due to cranial nerve ischemia. Gross total resection was achieved in seven of eight cases. The mean estimated blood loss during surgical resection was 186 mL (range, 39-392 mL). The mean operative time was 431 min (range, 317-767 min).

Conclusions: The MHT embolization of posterior fossa meningiomas by using n-BCA is technically feasible with a high success rate and an acceptable complication rate.

Abbreviations: MHT=meningohypophyseal trunk; ILT=inferolateral trunk; CPA=Cerebellopontine angle; BGC=balloon guide catheter; PVA=polyvinyl alcohol; GTR=Gross Total Resection; CN=Cranial nerve.

Background and purpose: CSF-venous fistulas are a common cause of spontaneous intracranial hypotension. The diagnosis and precise localization of these fistulas hinges on specialized myelographic techniques, which mainly include decubitus digital subtraction myelography and decubitus CT myelography (using either energy integrating or photon counting detector CT). A previous case series showed that cone beam CT myelography, performed as an adjunctive tool with digital subtraction myelography, increased the detection of CSF-venous fistulas. Here, we sought to determine the additive yield of cone beam CT myelography for CSF-venous fistula detection in a consecutive series of patients with spontaneous intracranial hypotension who underwent concurrent decubitus digital subtraction myelography and cone beam CT myelography.

Materials and methods: We retrospectively searched our institutional database for all consecutive patients who underwent decubitus digital subtraction myelography with adjunctive cone beam CT myelography between 8/5/2021 and 8/5/2024. We excluded any patients harboring extradural CSF on spine imaging, not meeting International Classification of Headache Disorders (3^rd edition) criteria for spontaneous intracranial hypotension, or not having undergone technically successful cone beam CT myelography in combination with digital subtraction myelography. All myelographic images were independently reviewed by two neuroradiologists. We calculated the diagnostic yield of both myelographic tests for localizing a CSF-venous fistula.

Results: We identified 100 patients who underwent decubitus digital subtraction myelography with adjunctive cone beam CT. We excluded 15 patients based on above criteria. 59/85 patients had a single definitive CSF-venous fistula. Among positive cases, the fistula was visible on digital subtraction myelography in 38/59 patients and visible on cone beam CT myelography in 59/59 patients. In 26/85 patients, no definitive fistula was identified on either modality.

Conclusions: Cone beam CT myelography increased the diagnostic yield for CSF-venous fistula detection and may be a useful addition to digital subtraction myelography.

Abbreviations: CB-CTM = cone beam CT myelography; CVF = CSF-venous fistula; DSM = digital subtraction myelography; EID-CTM = energy integrating detector CT myelography; PCD CTM = photon counting detector CT myelography; SIH = spontaneous intracranial hypotension.

Background and purpose:Cerebellar heterotopia (CH) is a neuroradiological abnormality poorly reported and investigated in the literature. It can be observed as an isolated finding, but it has been mainly reported in the context of cerebellar dysgenesis and in syndromic conditions. The aim of this study is to provide a comprehensive neuroradiological, clinical, and genetic characterization of a cohort of pediatric patients with cerebellar heterotopia.Materials and methods:Patients with a diagnosis of CH were systematically selected from the neuroimaging databases of the four Italian Centers participating in this retrospective study. For each patient, information regarding demographic, clinical, genetic and neuroradiological data were collected.Results:Thirty-two pediatric patients were recruited and subdivided into two groups: patients with isolated CH and/or cerebellar malformations (n= 18) and patients with CH associated with cerebral malformations (n=14). Isolated CH consistently showed a peripheral subcortical localization in the inferior portion of cerebellar hemispheres, with either unilateral or bilateral distribution. Ten patients belonging to the second group had a diagnosis of CHARGE syndrome, and their nodules of CH were mainly but not exclusively bilateral, symmetric, located in the peripheral subcortical zone and in the inferior portion of the cerebellar hemispheres; the remaining 4 patients of the second group, showed either bilateral or unilateral CH, located in both peripheral cortex and deep white matter and in the superior and inferior portions of cerebellum. Patients with isolated CH showed high prevalence of language development delay; neurodevelopmental disorders were the most represented clinical diagnoses. Recurring features were behavioral problems and motor difficulties. A conclusive genetic diagnosis was found in 18/32 patients.Conclusions:We found distinctive neuroradiological patterns of CH. Genetic results raise the possibility of a correlation between cerebellar morphological and functional developmental disruption, underscoring the importance of CH detection and reporting to orient the diagnostic path.Abbreviations CH Cerebellar heterotopia; MRI Magnetic resonance imaging; CC Corpus callosum; ASD autism spectrum disorder; IVH inferior vermian hypoplasia.

Background and purpose: Menière's disease (MD) is a condition of unknown etiology, involving genetic predisposition, autoimmune processes, viral infections, cellular apoptosis, and oxidative stress. This study aimed to investigate potential differences in the VII^th and VIII^th cranial nerves in MD patients using Hydrops-MRI (FLAIR) for morphometric evaluations.

Materials and methods: Using a 3T MRI scanner, constructive-interference-in-steady-state (CISS) and 3D-FLAIR-inversionrecovery (FLAIR) sequences were acquired. We evaluated the morphometrics of the VII^th and VIII^th cranial nerves from the cerebellopontine angle to the internal auditory canal fundus, comparing the non-affected and affected sides. Furthermore, we examined the findings in relation to symptom duration and evaluated feasibility of FLAIR-imaging in morphometry of cranial nerves.

Results: A total of 53 MD patients with unilateral symptoms were included. After statistical analysis, no significant differences were found regarding morphometric changes in the affected side compared to the non-affected side of the VII^th and VIII^th cranial nerves. There was also no significant difference between morphometric evaluations of patients with different symptom durations. The morphometric evaluation using Hydrops-MRI-Sequences (FLAIR) showed no significant difference compared to established morphometric highly T2-weighted imaging (CISS).

Conclusions: Our data found no differences in nerve morphometry between clinically non-affected and affected sides in unilateral MD patients, nor any correlation with symptom duration. This contrasts with previous findings of correlations between clinical features and endolymphatic hydrops. A disease process starting before clinical symptom onset could be a possible explanation. Morphometric evaluation of brain nerves using Hydrops-MRI-Sequences is practical and provides similar results to T2-weighted imaging, improving patient comfort and reducing MRI scan time.

Abbreviations: CN = cochlear nerve; CPA = cerebellopontine angle; CSA = cross-sectional area; FN = facial nerve; IAC = internal auditory canal; IVN = inferior vestibular nerve; LD = long diameter; MD = Menière's disease; SD = short diameter; SVN = superior vestibular nerve.

Background and purpose: Duplication of the pituitary gland is a rare developmental anomaly. Multiple associated craniofacial malformations have previously been reported with the largest series to date consisting of five patients. In this multi-institutional series of ten patients, we present a detailed review of the imaging features and discuss a possible overarching pathogenesis that would explain most of the detected malformations.

Materials and methods: Inclusion criteria for this retrospective imaging review were the presence of a pituitary stalk and gland duplication and the characteristic appearance of the hypothalamic ventral midline. In addition to the clinical presentation, we recorded the imaging findings of ten patients (9 female) through onsite and online reviews. Genetic analysis was available for six patients.

Results: The duplicated pituitary stalk and gland showed normal imaging appearances in all patients. Mammillary bodies were clearly identified lateral to the characteristic prominence of the hypothalamic ventral midline. Strands of tissue extending to the anterior dura ("limited ventral myeloschisis") were noted at the medulla oblongata in 10, and at the cervical spinal cord in 7 patients. The medulla oblongata showed a "butterfly" appearance on axial images in 9 patients. Ten patients had cervical segmentation anomalies ("zipper"-like), 9 anterior-posterior brainstem patterning defects (small pons, elongated medulla), and corpus callosum measurements were abnormal in all patients. Three patients each presented with diencephalic-mesencephalic junction abnormalities and 4 with an anterior mesencephalic "cap". An oropharyngeal teratoma was present in four patients. Genetics was normal in three of the six patients studied; the remainder were found to have mutations in EFNB1 and a gene variant of GIT1, two copies of 7. And 8. exon of SMN1 gene, and 2.126 megabase duplication at bands q11.1 and q11.2 of one chromosome 15, respectively.

Conclusions: Duplication of the pituitary gland presents as well-defined craniofacial and cervical spine malformation phenotype. Axial mesoderm duplication generating an excess of Sonic Hedgehog may be the primary embryological driver leading to this condition.

Abbreviations: CFNS＝ Craniofrontonasal Syndrome; DPG＝ Duplication of the Pituitary Gland; SHH＝ Sonic Hedgehog.