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1 November 2021, 5:31 pm
jross

1. Avila MJ, Hurlbert RJ. Central cord syndrome redefined. Neurosurg Clin N Am 2021;32:353–63. Available from: https://doi.org/10.1016/j.nec.2021.03.007

The pathophysiology of CCS typically occurs in the setting of preexisting stenosis and involves a low-impact/low-velocity hyperextension injury to the neck. This causes buckling of the ligamentum flavum at the lordotic apex of the cervical spine (C4-C6) resulting in spinal cord compression against osteophytes and disks protruding into the anterior canal, displacing the spinal cord parenchyma into the less stenotic lateral recesses. The epicenter of compression is in the sagittal midline but spreads laterally proportional to the force involved and degree of preexisting stenosis. Spinal cord gray matter is affected first because of stretch and shear to the transversely oriented sensory afferents crossing the midline and the arteriole blood supply; their side-to-side horizontal trajectory makes them more susceptible to damage from lateral displacement than the longitudinally oriented white matter tracts. Gray matter injury results in sensory disturbance to the hands. With higher injury forces shear and contusion extend laterally to involve white matter tracts in a medial to- lateral preference. Motor weakness of the hands is precipitated from indiscriminate lateral corticospinal pathway involvement. With greater injury force there is additional lateral, anterior, and posterior white matter involvement affecting arm, leg, bowel, and bladder function.

Of all the controversies surrounding CCS, the management of incomplete SCI in this setting is one of the most widely debated. In his original narrative, Schneider and coworkers described the surgical management of CCS to be “contraindicated because spontaneous improvement or complete recovery may occur. Furthermore, operation has actually been known to harm these patients rather than improve them.” In the 65 years ensuing since this warning, the philosophy of a more conservative approach toward surgical intervention for CCS continues to be championed and despaired.

Even more widely debated …

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5 October 2021, 5:22 pm
jross

1. Graff-Radford J, Lesnick T, Rabinstein AA, et al. Cerebral microbleeds: relationship to antithrombotic medications. Stroke 2021;52:2347–55. Available from: https://www.ahajournals.org/doi/10.1161/STROKEAHA.120.031515

Cerebral microbleeds (CMBs) are a risk factor for intracerebral hemorrhage (ICH) and are associated with increased risk of dementia and mortality. The prevalence of CMBs increases significantly with age, approaching forty percent by the age of 80 years. Established risk factors for CMBs include age, male sex, and hypertension. Antithrombotic medications have also been associated with increased risk of developing CMBs, but few population-based studies have evaluated this association. The authors sought to determine in a population-based study whether antithrombotic medications correlate with CMBs and, if present, whether the association was direct or mediated by another variable.

The study consisted of 1253 participants from the population-based Mayo Clinic Study of Aging who underwent T2* gradient-recalled echo magnetic resonance imaging. They tested the relationship between antithrombotic medications and CMB presence and location, using multivariable logistic-regression models.

Two hundred ninety-five participants (26.3%) had CMBs. Among 678 participants taking only antiplatelet medications, 185 (27.3%) had CMBs. Among 95 participants taking only an anticoagulant, 43 (45.3%) had CMBs. Among 44 participants taking an anticoagulant and antiplatelet therapy, 21 (48.8%) had CMBs. Anticoagulants correlated with the presence and frequency of CMBs, whereas antiplatelet agents were not. Structural equation models showed that predictors for presence/ absence of CMBs included older age at magnetic resonance imaging, male sex, and anticoagulant use.

They conclude that anticoagulant use correlated with presence of CMBs in the general population.

4 tables, 2 figures, no imaging

2. Preziosa P, Rocca MA, Filippi M. Central vein sign and iron rim in multiple sclerosis: ready for clinical use? Curr Opin Neurol 2021;34:505–13. Available from: https://journals.lww.com/10.1097/WCO.0000000000000946

The pathological hallmark of MS is the formation of demyelinating white matter lesions around venules. Cerebral veins and their …

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2 September 2021, 4:00 pm
jross

1. Alomari S, Lubelski D, Sacino AN, et al. Does myelopathy increase the morbidity and mortality of elective single-level anterior cervical discectomy and fusion? An updated propensity-matched analysis of 3938 patients from the American College of Surgeons National Surgical Quality Improvement Program database. Neurosurgery 2021;89:109–15

This present study used the American College of Surgeon National Surgical Quality Improvement Program (ACS-NSQIP) database to examine the effect of myelopathy on early morbidity and mortality after elective single-level ACDF. They employed a propensity score matching analysis to minimize the effects of any preoperative characteristic differences between the 2 cohorts. The authors hypothesized that patients undergoing ACDF for myelopathy versus radiculopathy would be significantly associated with worse postoperative outcomes.

Twenty percent of the cohort was myelopathic. These patients were significantly older, had more comorbidities, more likely to be functionally dependent, and to undergo emergency surgery when compared to the nonmyelopathic cohort. When 1969 myelopathic patients were 1:1 propensity matched with non-myelopathic patients, there was no difference between the myelopathic and nonmyelopathic patients in incidence of postoperative intensive care unit admission or death. Patients in the myelopathic group were significantly more likely to have a nonhome discharge and less likely to be discharged on the first postoperative day. Myelopathic patients had a higher rate of return to operating room within the same admission (2.2%) as well as a higher unplanned readmission rate (4.2%). The total operation time (143 min) and average length of hospital stay (52 h) were significantly higher in the myelopathic group when compared to the nonmyelopathic group (117 min) and (33 h), respectively.

Patients with myelopathy who undergo elective single-level ACDF have higher risks of several perioperative events including longer operative time, longer hospital stay, higher return to operating room, and unplanned readmission rates, when compared to nonmyelopathic patients.

The authors used …

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2 August 2021, 3:05 pm
jross

1. Ng WT, Tsang RKY, Beitler JJ, et al. Contemporary management of the neck in nasopharyngeal carcinoma. Head Neck 2021;43:1949–63. Available from: https://onlinelibrary.wiley.com/doi/10.1002/hed.26685

For patients who present with suspicious cervical lymphadenopathy, especially in the endemic regions where NPC is prevalent, initial examination may be endoscopic examination and biopsy of the NP, rather than fine-needle aspiration of the neck mass. Subsequent work up includes appropriate biopsy of the primary tumor and/or the node, physical examination with particular attention to cranial nerve function, plasma Epstein–Barr virus (EBV) DNA, CT scanning, MR, and FDG-PET. Radiotherapy with or without chemotherapy remains the primary modality of treatment, while surgery is reserved for persistent nodal disease or relapse.

With improvement in radiological diagnostic accuracy and better characterization of the natural history of NPC nodal spread, continual refinements have been suggested in the AJCC/UICC TNM staging system. Among the various nodal features, recent data suggest that nodal volume, ECE, nodal necrosis, and parotid node involvement carry adverse prognostic significance. Selective nodal irradiation according to individual nodal risk has been increasingly adopted, and early data based on this approach appear promising. Furthermore, gradient dose prescription using a lower dose elective nodal irradiation (ENI) to subclinical regions may serve a potentially useful strategy for dose de-escalation with the objective of reducing toxicity and improving quality of life. Amidst excellent nodal control with IMRT, salvage neck surgery remains the standard of care for patients who develop nodal failure, and continued research is required to define the extent of neck dissection and the role of adjuvant therapy after salvage neck surgery.

4 tables, 1 figure

2. Sabiq F, Huang K, Patel A, et al. Novel imaging classification system of nodal disease in human papillomavirus‐mediated oropharyngeal squamous cell carcinoma prognostic of patient outcomes. Head Neck 2021;43:1854–63. Available from: https://onlinelibrary.wiley.com/doi/10.1002/hed.26657

Matted nodes in …

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25 July 2021, 12:32 am
bookreviews

Malhotra A, Gandhi D, eds. Mukherji SK, consulting ed. Neuroimaging Clinics of North America: Evidence-Based Vascular Neuroimaging. Theclinics.com; 2021;31(2):139–264; $397.00

cover of Malhotra and Gandhi

The May 2021 issue of the Neuroimaging Clinics of North America concerns neurovascular imaging and is entitled Evidence-Based Vascular Neuroimaging. Edited by Drs. Malhotra and Gandhi, this issue contains 10 chapters with contributions from 25 authors.

What makes this publication valuable is that it addresses issues and topics that neuroradiologists face multiple times each day, such as detecting and dealing with unruptured intracranial aneurysms, imaging of vasospasm, extracranial vascular disease (with emphasis on plaque imaging), subarachnoid hemorrhage without a known cause, ischemic stroke with common parameters on MRI and CT, spontaneous intracerebral hemorrhage, AVMs, vessel wall imaging in intracranial vascular disease, and the use of CT algorithms in acute ischemic stroke.

While the chapter on unruptured intracranial aneurysms (UIAs) reviews some important points such as those related to eventual rupture/growth or key factors in describing aneurysms, the lack of any images to illustrate the authors’ points is a disappointment. There are innumerable features the authors describe but apparently decided not to show; such illustrations would have resulted in a greater impact of this material. On the other hand, the authors summarize the literature (evidence-based data) on UIAs. It is clear by the volume of studies in the literature and criteria used that many unanswered questions on management and aneurysm evaluation remain.

Documenting vasospasm and diagnosing delayed cerebral ischemia (DCI) are briefly discussed and important points re: Doppler US, DSA, CTA, and pCT are made. Better depiction of vasospasm should have been made, using larger formatted DSA imaging combined with properly placed labels.

The segment on extracranial vascular disease discusses and illustrates the important observations regarding arterial narrowing and plaque formation. The authors of this chapter do not illustrate important …

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