Preoperative MRI characteristics predict chronic subdural haematoma postoperative recurrence: a meta-analysis.

PURPOSE: Prior studies have reported that preoperative T1 magnetic resonance imaging (MRI) signal iso- or hypointensity may indicate higher risk of postoperative chronic subdural haematoma recurrence (cSDH). The authors undertook a meta-analysis to determine whether preoperative MRI characteristics may predict recurrence and/or reoperation after initial surgical evacuation of cSDH. MATERIALS AND METHODS: Embase, PubMed and Cochrane Library were queried to find articles published after 1990 that included data on preoperative brain MRIs obtained prior to burr hole or craniotomy haematoma evacuation of unilateral or bilateral cSDH and data on postoperative recurrence and/or repeat evacuation. The authors specifically investigated the T1 signal characteristics of the haematoma as they related to postoperative recurrence. RESULTS: Five articles were identified that included preoperative MRI T1 signal characteristics and postoperative recurrence data. One study reported cSDH recurrence requiring reoperation as the primary outcome, whereas four studies reported SDH recurrence alone as the primary outcome. A total of 1081 patients with a total of 1290 cSDHs underwent surgical evacuation. In the combined analysis, there were 62 recurrences in 300 cases (20.7%) in the MRI T1 hypo- and/or iso-intensity groups and 59 recurrences in 885 cases (6.7%) in the MRI T1 other groups (combined odds ratio = 4.385 (95% CI 2.93-6.57)). There was low heterogeneity among studies (i2 = 0%). CONCLUSION: This meta-analysis suggests that preoperative MRI T1 hypo- or isointensity cSDH signal may predict increased postoperative SDH recurrence risk.

Carotid intraplaque hemorrhage on vessel wall MRI does not correlate with TCD emboli monitoring in patients with recently symptomatic carotid atherosclerosis.

Background Carotid intraplaque hemorrhage (IPH) seen on vessel wall MRI is associated with an increased risk of stroke or transient ischemic attack, as are microembolic signals (MES) detected by transcranial Doppler (TCD). We sought to examine the association between IPH and MES in acute stroke patients with symptomatic carotid atherosclerosis. Methods Through a retrospective chart review, we included patients from 2011 to 2013 with acute ischemic stroke due to carotid atherosclerosis of varying stenosis who had both 3D volumetric MRI of the neck and TCD emboli monitoring. Results Twenty-four patients met the inclusion criteria. Mean time from stroke to MRI was 1.4 ± 1.9 days and to TCD was 2.6 ± 2.4 days. MES was seen in 10 patients (42%) and IPH was present in seven patients (29%), but we did not find a relationship between MES and IPH ( p = 0.64). Conclusion In patients with recent acute ischemic stroke attributed to carotid atherosclerosis, we did not detect an association between the presence of IPH and MES. While this small study may be underpowered, an alternate explanation is that MES and IPH reflect vulnerable carotid atherosclerosis through different mechanisms. This untested concept warrants prospective study in a larger cohort.

Delayed LGI1 seropositivity in voltage-gated potassium channel (VGKC)-complex antibody limbic encephalitis.

We utilise a clinical case to highlight why exclusion of voltage-gated potassium channel (VGKC)-complex autoantibody testing in serological evaluation of patients may delay or miss the diagnosis. A 68-year-old man presented with increasing involuntary movements consistent with faciobrachial dystonic seizures (FBDS). Initial evaluation demonstrated VGKC antibody seropositivity with leucine-rich glioma-inactivated 1 (LGI1) and contactin-associated protein-like 2 (CASPR2) seronegativity. Aggressive immunotherapy with methylprednisolone and plasmapheresis was started early in the course of his presentation. Following treatment with immunotherapy, the patient demonstrated clinical improvement. Repeat serum evaluation 4 months posthospitalisation remained seropositive for VGKC-complex antibodies, with development of LGI1 autoantibody seropositivity. VGKC-complex and LGI1 antibodies remained positive 12 months posthospitalisation. Our findings suggest that clinical symptoms can predate the detection of the antibody. We conclude that when suspicion for autoimmune encephalitis is high in the setting of VGKC autoantibody positivity, regardless of LGI1 or CASPR2 seropositivity, early immunotherapy and repeat testing should be considered.

Increased Incidence of Hypovitaminosis D Among Patients Requiring Treatment for Cerebral Aneurysms.

OBJECTIVE: Aneurysmal subarachnoid hemorrhage management is hampered by our incomplete understanding of what variables promote aneurysm formation, growth, and rupture. Because hypovitaminosis D has been identified as a risk factor for other vascular diseases, we examined its association with cerebral aneurysms requiring treatment. METHODS: We retrospectively reviewed charts of patients with cerebral aneurysms with recorded 25-hydroxy vitamin D levels undergoing treatment at our institution from May 2010 to May 2015. We compared these patients with a group of patients without aneurysms. We used multivariable Poisson regression and backward elimination to identify factors associated with cerebral aneurysms, with a threshold P < 0.20. A propensity-matching algorithm was used, incorporating all factors with P < 0.10 in our regression model. RESULTS: Patients in the aneurysm group were older than those in the control group (P = 0.001) and more likely to be female (P = 0.004), to be tobacco users (P < 0.001), and to have a diagnosis of hypertension (P = 0.001), but ethnicity, body mass index, and diabetes rates did not differ. Vitamin D levels in the aneurysm group were lower than in the control group (23.3 ± 12.3 vs. 28.7 ± 14.1 ng/mL, P = 0.001), and the patients were more likely to be vitamin D deficient (P = 0.028). Multivariable Poisson regression demonstrated that vitamin D level, tobacco use, age, and sex were significantly associated with aneurysms requiring treatment (P < 0.05). The propensity-matching algorithm confirmed a significant difference in vitamin D levels between the aneurysm and control groups (P = 0.01). CONCLUSIONS: Patients with cerebral aneurysms requiring treatment have a significantly higher incidence of hypovitaminosis D compared with patients in a control group.

Vertebral Artery Dissection and Cord Infarction - an Uncommon Cause of Brown-Séquard and Horner Syndromes.

This case report illustrates the neuroanatomy and neurovascular anatomy of the cervical spinal cord by exploring the pathophysiology of cervical cord infarction secondary to vertebral artery injury. The spinal cord is made up of several important tracts, including the dorsal column medial lemniscus system, corticospinal tracts, and the anterolateral system. Injury to one or more of these pathways can result in localizing neurological symptoms. Also contributing to the complexity of spinal vascular pathophysiology is the considerable variation to the cervical cord vascular anatomy. Understanding spinal cord function and neuroanatomy can aid in prompt diagnosis and management of ischemic cord lesions. In combination with a thorough clinical exam, advanced imaging techniques, such as diffusion tensor imaging, can not only localize the injury but also potentially help predict functional outcome.

Three-dimensional dynamic contrast enhanced imaging of the carotid artery with direct arterial input function measurement.

PURPOSE: Kinetic analysis using dynamic contrast enhanced MRI to assess neovascularization of carotid plaque requires images with high spatial and temporal resolution. This work demonstrates a new three-dimensional (3D) dynamic contrast enhanced imaging sequence, which directly measures the arterial input function with high temporal resolution yet maintains the high spatial resolution required to identify areas of increased adventitial neovascularity. THEORY AND METHODS: The sequence consists of multiple rapid acquisitions of a saturation prepared dynamic 3D gradient recalled echo (GRE) sequence temporally interleaved with multiple acquisitions of a 2D slice. The saturation recovery time was adjusted to maintain signal linearity with the very different contrast agent concentrations in the 2D slice and 3D volume. The K(trans) maps were obtained from the 3D dynamic contrast measurements while the 2D slice was used to obtain the arterial input function. Calibration and dynamic studies are presented. RESULTS: For contrast agent concentrations up to 5 mM, a saturation recovery time for the 2D slice of 20 ms resulted in less than a 10% deviation from the desired linear response of signal intensity with contrast agent concentration. The corresponding saturation recovery time of 83 ms for the 3D volume maintained less than a 10% deviation from the linear response up to contrast agent concentrations of 2 mM while a contrast agent concentration of 5 mM had almost a 30% deviation. There was a significant improvement in signal attenuation (9 ± 3% versus 23 ± 5% at 40 cm/s) when flow compensation was added to the slice select gradients. For patient studies, volume transfer and plasma fraction maps were calculated with data from the proposed sequence. CONCLUSION: This work demonstrated a novel sequence for 3D dynamic contrast enhanced imaging with a simultaneously acquired 2D slice that directly measures the arterial input function with high temporal resolution. Acquisition parameters can be adjusted to accommodate the full range of contrast agent concentration values to be encountered and the kinetic parameters obtained were consistent with expected values.