Author: jross

Jeffrey Ross • Mayo Clinic, Phoenix

Dr. Jeffrey S. Ross is a Professor of Radiology at the Mayo Clinic College of Medicine, and practices neuroradiology at the Mayo Clinic in Phoenix, Arizona. His publications include over 100 peer-reviewed articles, nearly 60 non-refereed articles, 33 book chapters, and 10 books. He was an AJNR Senior Editor from 2006-2015, is a member of the editorial board for 3 other journals, and a manuscript reviewer for 10 journals. He became Editor-in-Chief of the AJNR in July 2015. He received the Gold Medal Award from the ASSR in 2013.

Journal Scan – This Month in Other Journals, November 2017

Linzey JR, Wilson TJ, Sullivan SE, Thompson BG, Pandey AS. Frontal Sinus Breach During Routine Frontal Craniotomy Significantly Increases Risk of Surgical Site Infection: 10-Year Retrospective Analysis. Neurosurgery. 2017;0(0):1-8. doi:10.1093/neuros/nyx046.

Frontotemporal craniotomies are at particular risk for breaching the frontal sinus, especially when the patient has a large frontal sinus or the surgeon is attempting to expose anterior communicating (ACOM) artery aneurysms. Frontal sinus breach (FSB) has the potential to cause postoperative complications due to the introduction of microflora from the frontal sinus into the sterile environment of the intracranial compartment. 

In this retrospective study, the authors are attempting to determine if FSB is a risk factor for developing cranial surgical site infections in patients undergoing craniotomies for clip ligation of anterior circulation aneurysms. They hypothesized that the surgical site infection (SSI) rate for craniotomies with an FSB would be significantly higher than for craniotomies without an FSB, given the contamination of the intracranial compartment during FSB. This study included 862 patients undergoing 910 craniotomies. Primary outcome of interest was occurrence of a cranial surgical site infection. Of the 910 craniotomies, 141 (15.5%) involved FSB. Of those involving FSB, 22 (15.6%) developed a cranial surgical site infection, compared to only 56 of the 769 without FSB (7.3%). Cranial surgical site infection requiring reoperation was much more likely in patients with FSB compared to those without a breach (7.8% vs 1.6%). Patients with FSBs had 2 times the odds of developing a cranial surgical site infection as those without FSB. The authors overall infection rate of 8.6% for craniotomies is comparable with other published data.  In addition, the length of surgical procedure was associated with increased risk of infection, which supports previously published data.  As expected, longer procedures were also more common in patients with FSB compared to those …

Localizing the L5 Vertebra Using Nerve Morphology on MRI: An Accurate and Reliable Technique

Fellows’ Journal Club

The authors sought to determine whether the L5 vertebra could be accurately localized by using nerve morphology on MR imaging. A sample of 108 cases with full spine MR imaging were numbered from the C2 vertebral body to the sacrum. The reference standard of numbering by full spine imaging was compared with the nerve morphology numbering method with 5 blinded raters. The percentage of perfect agreement with the reference standard was 98.1%, which was preserved in transitional and numeric variation states. The iliolumbar ligament localization method showed 83.3% perfect agreement with the reference standard.

Improved Detection of Anterior Circulation Occlusions: The “Delayed Vessel Sign” on Multiphase CT Angiography

Fellows’ Journal Club

The authors evaluated 23 distal anterior circulation occlusions during a 2-year period. Ten M1-segment occlusions and 10 cases without a vessel occlusion were also included. There was significant improvement in the sensitivity of detection of distal anterior circulation vessel occlusions, overall confidence, and time taken to interpret with multiphase CTA compared with single-phase CTA. The delayed vessel sign is a reliable indicator of anterior circulation vessel occlusion, particularly in cases involving distal branches.

Multicenter Experience with FRED Jr Flow Re-Direction Endoluminal Device for Intracranial Aneurysms in Small Arteries

Editor’s Choice

The authors assessed the clinical safety and efficacy of the Flow Re-Direction Endoluminal Device Jr (FRED Jr) dedicated to small-vessel diameters between 2.0 and 3.0 mm in 42 patients with 47 aneurysms. The primary efficacy end point of complete or near complete occlusion was reached at 1 month in 27/41 (66%), at 6 months in 21/27 (78%), and at 12 months in 11/11 (100%) aneurysms.

Multinodular and Vacuolating Neuronal Tumor of the Cerebrum: A New “Leave Me Alone” Lesion with a Characteristic Imaging Pattern

Fellows’ Journal Club

The most recent 2016 WHO classification includes MVNT as a unique cytoarchitectural pattern of gangliocytoma, though it remains unclear whether MVNT is a true neoplastic process or a dysplastic hamartomatous/malformative lesion. The authors report 33 cases of presumed multinodular and vacuolating neuronal tumor of the cerebrum that exhibit a remarkably similar pattern of imaging findings consisting of a subcortical cluster of nodular lesions. They conclude that these are benign, nonaggressive lesions that do not require biopsy in asymptomatic patients and behave more like a malformative process than a true neoplasm.

Concordance of Time-of-Flight MRA and Digital Subtraction Angiography in Adult Primary Central Nervous System Vasculitis

Editor’s Choice

The authors compared the diagnostic concordance of vessel imaging using 3D-TOF-MRA and DSA in 85 patients with primary central nervous system vasculitis. Among the 25 patients with abnormal DSA findings, 24 demonstrated abnormal 3D-TOF-MRA findings, whereas all 6 remaining patients with normal DSA findings had normal 3D-TOF-MRA findings. They conclude that 3D-TOF-MRA shows a high concordance with DSA in diagnostic performance when analyzing vasculature in patients with primary central nervous system vasculitis and that with negative 3T 3D-TOF-MRA findings, the added diagnostic value of DSA is limited.

3D Pseudocontinuous Arterial Spin-Labeling MR Imaging in the Preoperative Evaluation of Gliomas

Editor’s Choice

Fifty-eight patients with pathologically confirmed gliomas underwent preoperative 3D pseudocontinuous arterial spin-labeling and ROC curves were generated for parameters to distinguish high-grade from low-grade gliomas. Both maximum CBF and maximum relative CBF were significantly higher in high-grade than in low-grade gliomas. After adjustment for age, a higher maximum CBF and higher maximum relative CBF were associated with worse progression-free survival.

Journal Scan – This Month in Other Journals, October 2017

Horn A, Reich M, Vorwerk J, et al. Connectivity Predicts deep brain stimulation outcome in Parkinson disease. Ann Neurol. 2017;82(1):67-78. doi:10.1002/ana.24974.

The benefit of deep brain stimulation (DBS) for Parkinson disease (PD) may depend on connectivity between the stimulation site and other brain regions, but which regions and whether connectivity can predict outcome in patients remain unknown. The authors attempted to identify the structural and functional connectivity profile of effective DBS to the subthalamic nucleus (STN) and test its ability to predict outcome.

The authors utilized a training dataset of 51 PD patients with subthalamic nucleus DBS which was combined with publicly available human connectome data (diffusion tractography and resting state functional connectivity) to identify connections reliably associated with clinical improvement (motor score of the Unified Parkinson Disease Rating Scale [UPDRS]). This connectivity profile was then used to predict outcome in an independent cohort of 44 patients. Resting state functional connectivity data was obtained on 1,000 healthy subjects using a 3T Siemens (Erlangen, Germany) MRI, part of the Brain Genomics Superstruct Project ( MRI data from 90 patients were obtained from the Parkinson’s Progression Markers Initiative (PPMI) database.  Scanning parameters can be found on the project website (www.ppmi-info.orgz). In the training dataset, connectivity between the DBS electrode and a distributed network of brain regions correlated with clinical response including structural connectivity to supplementary motor area and functional anticorrelation to primary motor cortex. This same connectivity profile predicted response in an independent patient cohort.

The authors cite four main conclusions: 1) a specific pattern of structural and functional connectivity with subthalamic nucleus DBS electrodes correlates with clinical outcome across patients in PD. 2) structural and functional connectivity are independent predictors of DBS response. 3) connectivity profiles derived from one patient cohort can predict clinical outcome in …

Hippocampal and Deep Gray Matter Nuclei Atrophy Is Relevant for Explaining Cognitive Impairment in MS: A Multicenter Study

Editor’s Choice

Brain dual-echo, 3D T1-weighted, and double inversion recovery scans were acquired at 3T from 62 patients with relapsing-remitting MS and 65 controls. Focal WM and cortical lesions were identified, and volumetric measures from WM, cortical GM, the hippocampus, and deep GM nuclei were obtained. Compared with those with who were cognitively preserved, patients with MS with cognitive impairment had higher T2 and T1 lesion volumes and a trend toward a higher number of cortical lesions. Significant brain, cortical GM, hippocampal, deep GM nuclei, and WM atrophy was found in patients with MS with cognitive impairment versus those who were cognitively preserved. The authors conclude that hippocampal and deep GM nuclei atrophy are key factors associated with cognitive impairment in MS.

Analysis of 30 Spinal Angiograms Falsely Reported as Normal in 18 Patients with Subsequently Documented Spinal Vascular Malformations

Fellows’ Journal Club

Eighteen patients with 19 lesions underwent a total of 30 negative spinal angiograms. The lesions included 9 epidural arteriovenous fistulas, 8 dural arteriovenous fistulas, and 2 perimedullary arteriovenous fistulas. Seventeen patients underwent endovascular (11) or surgical (6) treatment, with a delay ranging between 1 week and 32 months; the Aminoff-Logue score improved in 76.5%. Causes of the inadequate results included: 1) lesion angiographically documented but not identified (55.6%); 2) region of interest not documented (29.6%); or 3) level investigated but injection technically inadequate (14.8%). All the angiograms falsely reported as normal were caused by correctible, operator-dependent factors.