The Neuroradiology Journal

Head and neck squamous-cell carcinoma (HNSCC) related to human papillomavirus (HPV) infection represents a distinct biological and prognostic subtype compared to the HPV-negative form. Prior studies suggest a correlation between the apparent diffusion coefficient (ADC) values on diffusion-weighted imaging (DWI) of primary tumor lesion and HPV status in HNSCC. In this meta-analysis, we compared the average ADC of primary lesion between HPV-positive and HPV-negative HNSCC.

A comprehensive literature search of PubMed and Embase was performed. Studies comparing the average ADC on echo-planar DWI of primary tumor lesions between HPV-positive and HPV-negative HNSCC were included. The standardized mean difference was calculated using fixed- and random-effects models. Tau-squared estimates of total heterogeneity and Higgins inconsistency index (I² test) were determined.

A total of five studies, pooling data of 264 patients, were included for meta-analysis. Among these five studies, three had included oral cavity, hypopharyngeal, and/or laryngeal HNSCC in addition to oropharyngeal subsite. Primary lesions were comprised of 185 HPV-negative and 79 HPV-positive HNSCC. The meta-analysis showed lower average ADC values in HPV-positive HNSCC compared to the HPV-negative form, with a standardized mean difference of 0.961 (95% confidence interval 0.644–1.279; p < 0.0001). Since there was no significant heterogeneity in analysis (p = 0.3852), both random- and fixed-effects models resulted in the same estimates of overall effect.

HPV-positive HNSCC primary lesions have a lower average ADC compared to the HPV-negative form, highlighting the potential application of quantitative diffusion magnetic resonance imaging as a noninvasive imaging biomarker for prediction of HPV status.

The aim of this study was to determine whether apparent diffusion coefficient (ADC) bi-component curve-fitting histogram analysis and volume percentage change (VPC) prior to bevacizumab treatment can stratify progression-free survival (PFS) and overall survival (OS) in patients with glioblastoma multiforme (GBM) on first recurrence.

We retrospectively evaluated 17 patients with recurrent GBM who received bevacizumab and fotemustine (n = 13) or only bevacizumab (n = 4) on first recurrence at our institution between December 2009 and July 2015. Both T2/FLAIR abnormalities and enhancing tumor on T1 images were mapped to the ADC images. ADC-L and ADC-M values were obtained trough bi-Gaussian curve fitting histogram analysis. Furthermore, the study population was dichotomized into two subgroups: patients displaying a reduction in enhancing tumor volume of either >55% or <55% between the mean value calculated at baseline and first follow-up. Subsequently, a second dichotomization was performed according to a reduction in the T2 / FLAIR volume >41% or <41% at first check after treatment. OS and PFS were assessed using volume parameters in a Cox regression model adjusted for significant clinical parameters.

In univariate analysis, contrast-enhanced (CE)-ADC-L was significantly predictive of PFS (p = 0.01) and OS (p = 0.03). When we dichotomized our sample using the 55% cut-off for enhancing tumor volume, CE-VPC was able to predict PFS (p = 0.01) but not OS (p = 0.08). In multivariate analysis, only the CE-ADC-L was predictive of PFS (p = 0.01), albeit not predictive of OS (p = 0.14). CE-ADC-M, T2/FLAIR-ADC-L, T2/FLAIR-ADC, and T2/FLAIR VPC were not significantly predictive of PFS and OS (p > 0.05) in both univariate and multivariate analysis.

CE-ADC and CE-VPC can stratify PFS for patients with recurrent glioblastoma prior to bevacizumab treatment.

Magnetic resonance imaging (MRI) with a gadolinium injection is currently used in the follow-up of children in remission of cerebral tumors (CTs). Intracerebral gadolinium deposition has been recently reported with unknown risks. The aim of this study was to evaluate the sensitivity of unenhanced brain MRI (U-MRI) in detection of tumor recurrence.

A set of 58 U-MRIs of children in remission was retrospectively evaluated by three seniors (a neuroradiologist, a pediatric and a general radiologist) and one junior to look for any recurrence. Clinical, tumoral and imaging data were collected. The final diagnosis was anatomopathological when available, or the clinicoradiological evolution. Sensitivity, specificity, predictive values and interobserver agreement were calculated. A Fisher test and Fleiss kappa coefficient were performed.

For the seniors, the U-MRI had a sensitivity of 81% (95% confidence interval (CI): 0.56–0.90), and a negative predictive value (NPV) of 82% (95% CI: 0.63–0.94). The U-MRI sensitivity, regardless of the observer, was not significantly different from the contrast-enhanced MRI sensitivity (86%) according to a Fisher test (p > 0.05). No significant difference in sensitivity within the subgroups was found. The interobserver agreement of seniors was good (κ = 0.68).

U-MRI brain was suboptimal for 80% of patients. Three-dimensional millimetric, fluid-attenuated inversion recovery, and diffusion would constitute helpful sequences in follow-up. Further specific studies depending on each tumor type are still required to determine whether a potential abstention of gadolinium intravenous injection should be discussed for children.

Radiology descriptions of intracranial metastases following radiotherapy are often imprecise. This study sought to improve such reports by creating and disseminating a structured template that encourages discrete categorization of intracranial lesions.

Following initiation of the structured template, a retrospective review assessed patients with intracranial metastases that underwent radiotherapy, comparing ‘pre-template’ with ‘post-template’ reports. A total of 139 patients were included; 94 patients (67.6%) were imaged pre-template, 45 (32.4%) post-template. Reports were assessed for discrete versus non-specific descriptions of lesions: ‘(presumed) new metastases’, ‘treated metastases’, and ‘indeterminate lesions’. Non-specific language was subdivided based on the type of lesion(s) described: e.g. ‘stable enhancing foci’ was deemed a non-specific description of ‘treated metastases’.

Non-specific descriptions of lesions were used in 25/94 reports (26.6%) pre-template, and eight reports (17.8%) post-template. No significant difference was found in the frequency of inappropriate/ambiguous descriptions of intracranial lesions following template initiation (P = 0.52). However, only 27/45 (60.0%) of the reports in the post-template time period used the structured report; the other reports were written as free prose. Of the reports that did use the structured template, the authors used significantly less ambiguous language structured template (P = 0.02).

When utilized, a structured report template resulted in decreased non-specific descriptions and improved discrete characterization of intracranial metastases in patients treated with radiation. However, the frequency of non-specific language usage before and after template initiation was unchanged, probably due to poor compliance with template utilization.

This study compares computed tomography angiography-based collateral scoring systems in regard to their inter-rater reliability and potential to predict functional outcome after endovascular thrombectomy, and relates them to parenchymal perfusion as measured by computed tomography perfusion.

Eighty-four patients undergoing endovascular thrombectomy in anterior circulation ischaemic stroke were enrolled. Modified Tan Score, Miteff Score, Maas Score and Opercular Index Score ratio were assessed in pre-interventional computed tomography angiographies independently by two readers. Collateral scores were tested for inter-rater reliability by weighted-kappa, for correlations with three-months modified Rankin Scale, and their potential to differentiate between patients with favourable (modified Rankin Scale ≤2) and poor outcome (modified Rankin Scale ≥3). Correlations with relative cerebral blood volume and relative cerebral blood flow were tested in patients with available computed tomography perfusion.

Very good inter-rater reliability was found for Modified Tan, Miteff and Opercular Index Score ratio, and substantial reliability for Maas. There were no significant correlations between collateral scores and three-months modified Rankin Scale, but significant group differences between patients with favourable and poor outcome for Maas, Miteff and Opercular Index Score ratio. Miteff and Maas were significant predictors of favourable outcome in binary logistic regression analysis. Miteff best differentiated between both outcome groups in receiver-operating characteristics, and Maas reached highest sensitivity for favourable outcome prediction of 96%. All collateral scores significantly correlated with mean relative cerebral blood volume and relative cerebral blood flow.

Computed tomography angiography scores are valuable in estimating functional outcome after mechanical thrombectomy and reliable across readers. The more complex scores, Maas and Miteff, show the best performances in predicting favourable outcome.

Endovascular treatment for acute ischaemic stroke with large artery occlusion has become the standard of care. However, the question if a subgroup of patients, with a low cerebral blood volume Alberta Stroke Program Early CT score (CBV-ASPECTS) ≤ 7 should be excluded from endovascular treatment remains open. Therefore; we investigated the difference of outcome between patients who were treated by endovascular treatment vs patients who did not receive endovascular treatment.

We retrospectively analysed our stroke database for all patients who presented within six hours of onset with unfavourable imaging findings and who received endovascular treatment or best medical treatment alone. Unfavourable imaging was defined as a CBV-ASPECTS ≤ 7, which was an exclusion criterion for endovascular treatment at our institution before 2015.

From 60 patients with an initial CBV-ASPECTS ≤ 7, 40 received best medical treatment and 20 were treated with endovascular treatment. Arterial hypertension and atrial fibrillation was more present in patients without endovascular treatment, the other baseline characteristics and percentage of patients treated with intravenous recombinant tissue plasminogen activator were not significantly different in both groups. At discharge, 40% of the interventional treated patients had a favourable outcome (eight of 20 (40%) vs six of 40 (15%; p = 0.031). The median values of the National Institute of Health Stroke Score and modified Rankin Scale at discharge were significantly lower in the treated cohort (6.5 (2.5–10.5) vs 16 (9.5–22.5); p = 0.006; 3 (0–5.5) vs 5 (4.5–5.5); p = 0.003).

Patients with a CBV-ASPECTS ≤ 7 are likely to benefit from therapy and therefore may not be excluded from endovascular treatment. Further randomised trials are warranted to validate the data.

Carotid artery stenting (CAS) is a valuable alternative to carotid endarterectomy, especially in high-risk patients. However, the reported incidences of perioperative stroke and death remain higher than for carotid endarterectomy, even when using embolic protection devices (EPDs) during CAS. Our purpose was to evaluate 30-day major adverse events after CAS when selecting the most appropriate EPD.

We reviewed the clinical outcomes of 61 patients with 64 lesions who underwent CAS with EPDs. Patients who underwent CAS associated with thrombectomy and who had a preoperative modified Rankin scale score >3 were excluded from the analysis. The EPD was selected based on symptoms, carotid wall magnetic resonance imaging and lesion length, and we analyzed combined 30-day complication rates (transient ischemic attack, minor stroke, major stroke or death).

Forty-nine patients were men and 12 were women. The median age was 72 years (range: 59–89 years) and 44 lesions were asymptomatic. A filter-type EPD was selected in 23 procedures, distal-balloon protection in 14 procedures and proximal-occlusive protection in 27 procedures. Two patients (3.1%) experienced a transient ischemic attack and one patient (1.6%) had a minor stroke within 30 days of the procedure. No patients experienced procedure-related morbidities (modified Rankin score >2) or death.

The perioperative stoke rate was low when we selected a proximal-occlusive-type EPD in high-risk patients with vulnerable carotid artery disease. Our algorithm for EPD selection was an effective tool in the perioperative management of carotid artery stenosis.

Multiphase computed tomography angiography (MP-CTA) is an innovative imaging tool that can give those managing acute ischemic stroke temporal information on degree and extent of pial collateral arterial filling in the affected brain. We sought to estimate the incidence of false-positive or -negative evaluation of the carotid bifurcation or intracranial thrombus on single-phase CTA (SP-CTA) compared with MP-CTA.

A single-center, retrospective consecutive review was conducted of imaging and clinical records of 150 patients in two months who presented with neurological symptoms with a National Institutes of Health Stroke Scale score ≥ 2 and who received an MP-CTA as part of their investigative work-up. The cohort consisted of 52.3% male and 47.7% female patients. Median individual age was 68 years (interquartile range 60–79). Extracranial and intracranial vessel images of the initial early arterial phase were evaluated and compared with late arterial and early venous phase images.

In the cohort of 150 patients, in three patients (2%) SP-CTA would have led to an incorrect diagnosis and management without MP-CTA–acquired source imaging. The three scenarios represented differentiating a carotid string sign from internal carotid artery occlusion, determining the appearance and extent of thrombus in carotid T-occlusion, and differentiating slow flow and contrast mixing-related artifacts from intraluminal thrombus.

In addition to improving assessment of collateral circulation in acute stroke patients, MP-CTA is also useful in assessing specific flow-related scenarios for which SP-CTA may give spurious results.