Universal screening for blunt cerebrovascular injury.

BACKGROUND: Blunt cerebrovascular injury (BCVI) can result in thromboembolic stroke. Many trauma centers selectively screen patients with cervical computed tomographic angiography (CTA) based on clinical criteria. In 2016, our institution adopted universal screening for BCVI for all blunt trauma patients. The aim of this study was to accurately determine the incidence of BCVI and to evaluate the diagnostic performance of the Denver criteria (DC), expanded Denver criteria (eDC), and Memphis criteria (MC) in selecting patients for screening. METHODS: Retrospective cohort study of adult (≥16 years) blunt trauma patients who presented to the Level I trauma center at University of Alabama at Birmingham. We reviewed all CTA reports and selected CTA images to obtain the true incidence rate of BCVI. We then evaluated the diagnostic performance of the DC, eDC, and MC. RESULTS: A total of 6,800 patients who had suffered blunt trauma were evaluated, of whom 6,287 (92.5%) had a neck CTA. Of these, 480 (7.6%) patients had CTA evidence of BCVI. The eDC identified the most BCVI cases (sensitivity 74.7%) but had the lowest positive predictive value (14.6%). The DC and MC had slightly greater positive predictive values (19.6% and 20.6%, respectively) and had the highest diagnostic ability in terms of likelihood ratio (2.8 and 2.9) but had low sensitivity (57.5% and 47.3%). Consequently, if relying on the traditional screening criteria, the DC, eDC, and MC would have respectively resulted in 42.5%, 25.3%, and 52.7% of patients with BCVI identified by universal screening not receiving a neck CTA to screen for BCVI. CONCLUSION: Blunt cerebrovascular injury is even more common than previously thought. The diagnostic performance of selective clinical screening criteria is poor. Consideration should be given to the implementation of universal screening for BCVI using neck CTA in all blunt trauma patients. LEVEL OF EVIDENCE: Diagnostic, level III.

Best practice guidelines for blunt cerebrovascular injury (BCVI).

Blunt cerebrovascular injury (BCVI) is a non-penetrating injury to the carotid and/or vertebral artery that may cause stroke in trauma patients. Historically BCVI has been considered rare but more recent publications indicate an overall incidence of 1-2% in the in-hospital trauma population and as high as 9% in patients with severe head injury. The indications for screening, treatment and follow-up of these patients have been controversial for years with few clear recommendations. In an attempt to provide a clinically oriented guideline for the handling of BCVI patients a working committee was created. The current guideline is the end result of this committees work. It is based on a systematic literature search and critical review of all available publications in addition to a standardized consensus process. We recommend using the expanded Denver screening criteria and CT angiography (CTA) for the detection of BCVI. Early antithrombotic treatment should be commenced as soon as considered safe and continued for at least 3 months. A CTA at 7 days to confirm or discard the diagnosis as well as a final imaging control at 3 months should be performed.

[Mechanical thrombectomy: Acute complications and delayed sequelae]. / Mechanische Thrombektomie : Akutkomplikationen und Spätfolgen.

BACKGROUND: Due to the positive evidence for mechanical thrombectomy (mTE), it will be increasingly used in future. Profound knowledge of potential complications, prevention and management of complications is necessary to safely implement mTE into clinical practice. AIM: Description of specific complications of mTE and their clinical relevance, measures for prevention and management. Summary of the current knowledge on long-term side effects of mTE. MATERIAL AND METHODS: Analysis of current trial results and selected case series to address specific topics. Summary of own practical clinical experience. RESULTS: Vascular injury (1-5%) and emboli (5-9%) are the most relevant intraprocedural complications but the clinical outcome is variable. Measures for prevention and management are described in detail. Vasospasms frequently occur (20-26%) but rarely need specific treatment and do not affect the clinical course. In the case of restrictive indications the frequency of symptomatic hemorrhage is similar to that for medicinal treatment (up to 8%). Contrast medium enhancement in the area of the infarction on post-treatment imaging should not be mistaken for hemorrhages. Focal subarachnoid contrast medium enhancement or hemorrhage occurs in up to 24% of cases and is predominantly benign. In follow-up imaging stenoses or occlusions can be detected in 4-10% of the treated vessels, most of which are asymptomatic. They are considered to be caused by microtrauma to the vascular wall. CONCLUSION: Clinically relevant complications of mTE are rare. Preventive measures and effective management of complications may even increase safety. Stenoses occasionally occur as a long-term side effect but are asymptomatic in the majority of cases.

TGFß-activated Kinase 1 (TAK1) Inhibition by 5Z-7-Oxozeaenol Attenuates Early Brain Injury after Experimental Subarachnoid Hemorrhage.

Accumulating evidence suggests that activation of mitogen-activated protein kinases (MAPKs) and nuclear factor NF-κB exacerbates early brain injury (EBI) following subarachnoid hemorrhage (SAH) by provoking proapoptotic and proinflammatory cellular signaling. Here we evaluate the role of TGFß-activated kinase 1 (TAK1), a critical regulator of the NF-κB and MAPK pathways, in early brain injury following SAH. Although the expression level of TAK1 did not present significant alternation in the basal temporal lobe after SAH, the expression of phosphorylated TAK1 (Thr-187, p-TAK1) showed a substantial increase 24 h post-SAH. Intracerebroventricular injection of a selective TAK1 inhibitor (10 min post-SAH), 5Z-7-oxozeaenol (OZ), significantly reduced the levels of TAK1 and p-TAK1 at 24 h post-SAH. Involvement of MAPKs and NF-κB signaling pathways was revealed that OZ inhibited SAH-induced phosphorylation of p38 and JNK, the nuclear translocation of NF-κB p65, and degradation of IκBα. Furthermore, OZ administration diminished the SAH-induced apoptosis and EBI. As a result, neurological deficits caused by SAH were reversed. Our findings suggest that TAK1 inhibition confers marked neuroprotection against EBI following SAH. Therefore, TAK1 might be a promising new molecular target for the treatment of SAH.

Protective effect of docosahexaenoic acid against brain injury in ischemic rats.

Evidence suggests that inactivation of cell-damaging mechanisms and/or activation of cell-survival mechanisms may provide effective preventive or therapeutic interventions to reduce cerebral ischemia/reperfusion (I/R) injuries. Docosahexaenoic acid (DHA) is an essential polyunsaturated fatty acid in the central nervous system that has been shown to possess neuroprotective effects. We examined whether different preadministrative protocols of DHA have effects on brain injury after focal cerebral I/R and investigated the potential neuroactive mechanisms involved. Sprague-Dawley rats were intraperitoneally pretreated with DHA once 1 h or 3 days being subjected to focal cerebral I/R or daily for 6 weeks before being subjected to focal cerebral I/R. Reduction of brain infarction was found in all three DHA-pretreated groups. The beneficial effect of DHA on the treatment groups was accompanied by decreases in blood-brain barrier disruption, brain edema, malondialdehyde (MDA) production, inflammatory cell infiltration, interleukin-6 (IL-6) expression and caspase-3 activity. Elevation of antioxidative capacity, as evidenced by decreased MDA level and increased superoxide dismutase activity and glutathione level, was detected only in the chronic daily-administration group. The two single-administration groups showed increased phosphorylation of extracellular-signal-regulated kinase (ERK). Elevation of Bcl-2 expression was detected in the chronic daily-administration and 3-day-administration groups. In vitro study demonstrated that DHA attenuated IL-6 production from stimulated glial cells involving nuclear factor kappaB inactivation. Therefore, the data suggest that the neuroprotective mechanisms of DHA pretreatment are, in part, mediated by attenuating damaging mechanisms through reduction of cytotoxic factor production and by strengthening survival mechanisms through ERK-mediated and/or Bcl-2-mediated prosurvival cascade.

Intraoperative angiography to prevent vertebral artery injury during reduction of a dislocated hangman fracture. Case report.

The authors report on a 38-year-old woman with a dislocated hangman fracture associated with unilateral vertebral artery (VA) occlusion. The patient presented with a mild central cord syndrome, as well as anterior subluxation of the C-2 vertebral body upon C-3, bilateral neural arch fractures, and a unilateral locked facet joint. Digital subtraction angiography revealed occlusion of the right VA, with the posterior cerebral circulation entirely dependent on the left VA. Intraoperative angiography demonstrated that complete reduction of the dislocation would have caused severe stenosis of the left VA; partial reduction and anterior fixation were performed instead, with excellent neurological outcome. In this case, intraoperative angiography was particularly useful for preventing brain-related ischemic complications during reduction.

Endoscopic reverse third ventriculostomy via the cisterna magna: anatomical study and proposal of a novel procedure.

Basilar artery injury has been known as a potential lethal complication of endoscopic third ventriculostomy. In order to avoid this complication, endoscopic reverse third ventriculostomy via a trans-cisterna-magna route was studied. A cadaveric study was performed for navigation of a flexible endoscope through the cisterna magna. Three fresh, unfixed cadavers were used for this endoscopic navigation. In the prone position, a small vertical paramedian skin incision is made at the mid-portion of the posterior neck. An 11-mm threaded plastic tube is inserted towards the posterior arch of the atlas. After a partial hemilaminectomy of the atlas, a flexible endoscope is introduced into the cisterna magna and is navigated cephalad along the vertebrobasilar artery to the inferior aspect of the floor of the third ventricle. Through the working channel of a fiberscope, third ventriculostomy is performed in a reverse direction. Additional detailed anatomy was studied in fixed cadaveric head specimens with a rigid rod-lens endoscope for anatomic orientation. A novel technique of a trans-cisterna-magna reverse third ventriculostomy was studied in cadaveric specimens. This technique may avoid basilar artery injury which occurs occasionally during conventional third ventriculostomy.

Intermittent isometric exposure prevents brain retraction injury under venous circulatory impairment.

It is recognized that surgical obliteration of the cerebral veins by additional brain compression using retractors is dangerous. However, there is a lack of satisfactory management of this problem. We investigated whether intermittent brain compression can reduce brain injury from cerebral venous circulation disturbances (CVCDs). In Wistar rats (n = 25), a solitary cortical vein was occluded photochemically. The brain surface was compressed by a spring balance and constant compression at 30 mmHg was carried out for 60 min. Intermittent procedure compression protocols included four 15 min compressions at 5 min intervals, intermittent isometric exposure (IM), and intermittent isotonic exposure (IT). Local cerebral blood flow (ICBF) in the compressed area was measured together by laser-Doppler (LD) with the degree of brain compression. After 24 h, the brains were examined histologically. The animals were divided into the following five groups (each n = 5): 1, a sham operated control; 2, cortical vein occlusion (VO); 3, VO + continuous brain compression (CC); 4, VO + IM; and 5, VO + IT. The ICBF decreased significantly during the compression; however, recovery after the series of compressions was observed only in the VO + IM group, not in the VO + CC and the VO + IT groups (p < 0.05). The depth of the brain surface increased stepwise in the VO + IT group compared with the VO + IM group (p < 0.01). The resulting tissue damage was significantly larger in the VO + CC and VO + IT groups than in the vein occlusion group (p < 0.05), but not in the VO + IM group. The results of the present study suggest that intermittent isometric exposure under CVCDs could decrease brain retraction injury during neurosurgical operations and be more beneficial than continuous compression, providing that the compression pressure declines as the process advances.