Evaluation of the Modified Barium Swallow Study Conducted With and Without Radiologist Supervision: A Pre- and Post-Observational Study.

PURPOSE: Assess quality metrics of modified barium swallow studies (MBSS) with and without a radiologist present during the procedure. METHODS: Retrospective review of MBSS performed on adult inpatients at a tertiary care hospital 6-months pre- and post-institutional change from having to not having a radiologist present during the examination. FACTORS ASSESSED INCLUDED: fluoroscopy time; study duration; number of cine loops; number of images; efficiency of collimation (using a 5-point scoring system); time to final report; radiologist-speech language pathologist report disagreement; and recalls for inadequate studies. Statistical analysis was via Welch's t-test and a test of proportions for continuous and count data under the normal approximation. RESULTS: 106 and 119 MBSS were analyzed from the radiologist present and radiologist absent periods, respectively. No statistically significant differences were found for: average fluoroscopy time (116.1 s vs. 126.9 s; P = 0.161); study duration (400.4 s vs. 417.3 s; P = 0.453); number of cine loops (9.3 vs. 10.2; P = 0.075); number of images (620.5 vs. 581.1; P = 0.350); or report disagreement. There was improved performance without the radiologist present for collimation (1.92 vs. 1.43; P = 0.003) and fewer non-diagnostic images (6.5 vs. 4.5; P = 0.001). Time to final report was longer with the radiologist absent due to more reports with significant delays. There were no repeated studies because of inadequate technique in either group. CONCLUSION: MBSS performed by technologists without radiologist supervision is not inferior to those performed with radiologist supervision on multiple performance measures. This supports technologist operated MBSS without radiologist supervision, while acknowledging a need to further address radiologist report time delay.

The Effect of Tumor Neovasculature on Functional Magnetic Resonance Imaging Blood Oxygen Level-Dependent Activation.

BACKGROUND: We report the case of a 40-year-old patient with a large, World Health Organization grade III oligodendroglioma in the left parietal lobe. CASE DESCRIPTION: Presurgical planning included functional magnetic resonance imaging (fMRI) localization of language, motor, and somatosensory processing. fMRI results for motor and somatosensory tasks revealed activation in perilesional regions near the surgical resection as well as deactivation in the tumor for the sensory task, suggesting decreased autoregulation in the region owing to the glioma. fMRI results showed left-hemisphere dominance for language and activation in perilesional regions for all 3 speech tasks (i.e., word reading, picture naming, and semantic questions). In addition, the results demonstrated that the high vascularity of the lesion altered the blood oxygen level-dependent function, resulting in false-positive and false-negative activation in the semantic questions and leg/foot rubbing task, respectively. Intraoperative direct cortical stimulation was conducted in the regions corresponding to fMRI activation while the patient performed motor, sensory, and language tasks and showed no loss of function. Follow-up fMRI revealed that there was no longer activation in the tumor or in perilesional regions, presumably owing to the resection of the vascularized tumor. CONCLUSIONS: This case highlights the importance of presurgical fMRI to inform the neurosurgical approach and emphasizes the need for careful interpretation of fMRI data, especially in cases of malignant glioma, which can decrease autoregulation in surrounding regions, affecting fMRI blood oxygen level-dependent signal.

Reorganized neural activation in motor cortex following subdural fluid collection: an fMRI and DTI study.

We report a patient with a cavernous malformation involving the right lentiform nucleus. Pre-surgical planning included fMRI localization of language, motor, and sensory processing, and DTI of white matter tracts. fMRI results revealed no activation near the planned resection zone. However, post-surgery the patient developed a subdural fluid collection, which applied pressure to the primary motor cortex (M1). Follow-up scans revealed that motor activation had shifted due to pressure, and then shifted to a new location after the fluid collection subsided. This case report suggests that long-term neural reorganization can occur in response to short term compression in the cortex.

Prevalence of Extracranial Venous Narrowing on Magnetic Resonance Venography Is Similar in People With Multiple Sclerosis, Their Siblings, and Unrelated Healthy Controls: A Blinded, Case-Control Study.

PURPOSE: The study sought to assess and compare the prevalence of narrowing of the major extracranial veins in subjects with multiple sclerosis and controls, and to assess the sensitivity and specificity of magnetic resonance venography (MRV) for describing extracranial venous narrowing as it applies to the chronic cerebrospinal venous insufficiency theory, using catheter venography (CV) as the gold standard. METHODS: The jugular and azygos veins were assessed with time-of-flight MRV in this assessor-blinded, case-control study of subjects with multiple sclerosis, their unaffected siblings, and unrelated controls. The veins were evaluated by diameter and area, and compared with CV. Collateral vessels were also analyzed for maximal diameter, as a potential indicator of compensatory flow. RESULTS: A high prevalence of extracranial venous narrowing was demonstrated in all study groups, collectively up to 84% by diameter criteria and 90% by area, with no significant difference between the groups when assessed independently (P = .34 and .63, respectively). There was high interobserver variability in the reporting of vessel narrowing (kappa = 0.32), and poor vessel per vessel correlation between narrowing on MRV and CV (kappa = 0.064). Collateral neck veins demonstrated no convincing difference in maximum size or correlation with jugular narrowing. CONCLUSION: There is a high prevalence of narrowing of the major extracranial veins on MRV in all 3 study groups, with no significant difference between them. These findings do not support the chronic cerebrospinal venous insufficiency theory. Although MRV has shown a high sensitivity for identifying venous narrowing, time-of-flight imaging demonstrates poor interobserver agreement and poor specificity when compared with the gold standard CV.

Presurgical language mapping in epilepsy: Using fMRI of reading to identify functional reorganization in a patient with long-standing temporal lobe epilepsy.

We report a 55-year-old, right-handed patient with intractable left temporal lobe epilepsy, who previously had a partial left temporal lobectomy. The patient could talk during seizures, suggesting that he might have language dominance in the right hemisphere. Presurgical fMRI localization of language processing including reading of exception and regular words, pseudohomophones, and dual meaning words confirmed the clinical hypothesis of right language dominance, with only small amounts of activation near the planned surgical resection and, thus, minimal eloquent cortex to avoid during surgery. Postoperatively, the patient was rendered seizure-free without speech deficits.

Pre-Surgical Integration of fMRI and DTI of the Sensorimotor System in Transcortical Resection of a High-Grade Insular Astrocytoma.

Herein we report on a patient with a WHO Grade III astrocytoma in the right insular region in close proximity to the internal capsule who underwent a right frontotemporal craniotomy. Total gross resection of insular gliomas remains surgically challenging based on the possibility of damage to the corticospinal tracts. However, maximizing the extent of resection has been shown to decrease future adverse outcomes. Thus, the goal of such surgeries should focus on maximizing extent of resection while minimizing possible adverse outcomes. In this case, pre-surgical planning included integration of functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI), to localize motor and sensory pathways. Novel fMRI tasks were individually developed for the patient to maximize both somatosensory and motor activation simultaneously in areas in close proximity to the tumor. Information obtained was used to optimize resection trajectory and extent, facilitating gross total resection of the astrocytoma. Across all three motor-sensory tasks administered, fMRI revealed an area of interest just superior and lateral to the astrocytoma. Further, DTI analyses showed displacement of the corona radiata around the superior dorsal surface of the astrocytoma, extending in the direction of the activation found using fMRI. Taking into account these results, a transcortical superior temporal gyrus surgical approach was chosen in order to avoid the area of interest identified by fMRI and DTI. Total gross resection was achieved and minor post-surgical motor and sensory deficits were temporary. This case highlights the utility of comprehensive pre-surgical planning, including fMRI and DTI, to maximize surgical outcomes on a case-by-case basis.

Attentional Network Differences Between Migraineurs and Non-migraine Controls: fMRI Evidence.

Migraine is a headache disorder characterized by sensitivity to light and sound. Recent research has revealed abnormal visual-spatial attention in migraineurs in between headache attacks. Here, we ask whether these attentional abnormalities can be attributed to specific regions of the known attentional network to help characterize the abnormalities in migraine. Specifically, the ventral frontoparietal network of attention is involved with assessing the behavioural relevance of unattended stimuli. Given the decreased suppression of unattended stimuli reported in migraineurs, we hypothesized that migraineurs would have abnormal processing in the ventral portion of the frontoparietal network of attention. To address this, we used functional magnetic resonance imaging to assess the attentional control networks during visual spatial-orienting tasks in migraineurs (N = 16) as compared to non-migraine controls (N = 16). We employed two visual orienting paradigms with target discrimination tasks: (1) voluntary orienting to central arrow cues, and (2) reflexive orienting to peripheral flash cues. While both groups showed activation in the key areas of attentional processing networks, migraineurs showed less activation than non-migraine controls in a key area of the ventral frontoparietal network of attention, the right temporal parietal junction (rTPJ), during both voluntary and reflexive visual spatial orienting. Given the role of rTPJ is to assess the visual environment for behaviorally relevant sensory stimuli outside the focus of attention and signal other attentional areas to reorient attention to behaviorally salient stimuli, our findings fit with previous research showing that migraineurs lack suppression of unattended events and have heightened orienting to sudden onset stimuli in peripheral locations.

Inclusion of attentional networks in the pre-surgical neuroimaging assessment of a large deep hemispheric cavernous malformation: an FMRI case report.

BACKGROUND AND IMPORTANCE: Functional magnetic resonance imaging (fMRI) is a noninvasive and reliable tool for mapping eloquent cortex in patients prior to brain surgery. Ensuring intact perceptual and cognitive processing is a key goal for neurosurgeons, and recent research has indicated the value of including attentional network processing in pre-surgical fMRI in order to help preserve such abilities, including reading, after surgery. CLINICAL PRESENTATION: We report a 42-year-old patient with a large cavernous malformation, near the left basal ganglia. The lesion measured 3.8 × 1.7 × 1.8 cm. In consultation with the patient and the multidisciplinary cerebrovascular team, the decision was made to offer the patient surgical resection. The surgical resection involved planned access via the left superior parietal lobule using stereotactic location. The patient declined an awake craniotomy; therefore, direct electrocortical stimulation (ECS) could not be used for intraoperative language localization in this case. Pre-surgical planning included fMRI localization of language, motor, sensory, and attentional processing. The key finding was that both reading and attention-processing tasks revealed consistent activation of the left superior parietal lobule, part of the attentional control network, and the site of the planned surgical access. Given this information, surgical access was adjusted to avoid interference with the attentional control network. The lesion was removed via the left inferior parietal lobule. The patient had no new neurologic deficits postoperatively but did develop mild neuropathic pain in the left hand. CONCLUSION: This case report supports recent research that indicates the value of including fMRI maps of attentional tasks along with traditional language-processing tasks in preoperative planning in patients undergoing neurosurgery procedures.

Risk of hippocampal metastases in small cell lung cancer patients at presentation and after cranial irradiation: a safety profile study for hippocampal sparing during prophylactic or therapeutic cranial irradiation.

PURPOSE: Neurocognitive impairment (NI) in patients with small cell lung cancer (SCLC) after whole brain radiation treatment (WBRT) is a significant cause of morbidity. Hippocampal avoidance (HA) during WBRT may mitigate or prevent NI in such patients. However, this has not been tested in SCLC patients. The estimated risk of metastases in the HA region (HM) in patients with SCLC at diagnosis or after WBRT is unknown. Our study aimed to determine the risk of HM in patients with SCLC and to assess correlated clinical factors. METHODS AND MATERIALS: Patients with SCLC who experienced brain metastases (BM) at presentation (de novo) or after WBRT treated at the Saskatoon Cancer Centre between 2005 and 2012 were studied. Relevant neuroimaging was independently reviewed by a neuroradiologist. HM was defined as metastases within 5 mm of the hippocampus. Logistic regression analysis was performed to assess correlation between various clinical variables and HM. RESULTS: Seventy eligible patients were identified. Of 59 patients presenting with de novo BM, 3 patients (5%, 95% confidence interval [CI]: 0%-10.7%) had HM. Collectively there were 359 (range, 1-33) de novo BM with 3 (0.8%, 95% CI: 0%-1.7%) HM deposits. Twenty patients experienced progression of metastatic disease in the brain after WBRT. Of the 20 patients, only 1 patient (5%, 95% CI: 0%-14.5%) experienced HM. On logistic regression, no factors significantly correlated with HM. CONCLUSION: The overall incidence of HM before or after WBRT in SCLC patients is low, providing preliminary support for the safety of HA during planned clinical trials of HA-WBRT for SCLC.