No abstract

No abstract

Background: Pathophysiological mechanisms underlying the syringomyelia associated with Chiari I malformation (CM-1) are still not completely understood, and reliable predictors of the outcome of posterior fossa decompression (PFD) are lacking accordingly. The reported prospective case-series study aimed to prove the existence of a pulsatile, biphasic systolic–diastolic cerebrospinal fluid (CSF) dynamics inside the syrinx associated with CM-1 and to assess its predictive value of patients' outcome after PFD. Insights into the syringogenesis are also reported. Methods: Fourteen patients with symptomatic CM-1 syringomyelia underwent to a preoperative neuroimaging study protocol involving conventional T1/T2 and cardiac-gated cine phase-contrast magnetic resonance imaging sequences. Peak systolic and diastolic velocities were acquired at four regions of interest (ROIs): syrinx, ventral, and dorsal cervical subarachnoid space and foramen magnum region. Data were reported as mean ± standard deviation. After PFD, the patients underwent a scheduled follow-up lasting 3 years. One-way analysis of variance with Bonferroni Post hoc test of multiple comparisons was performed P was <0.001. Results: All symptoms but atrophy and spasticity improved. PFD caused a significant velocity changing of each ROI. Syrinx and premedullary cistern velocities were found to be decreased within the 1 st month after PFD (<0.001). A caudad and cephalad CSF jet flow was found inside the syrinx during systole and diastole, respectively. Conclusion: Syrinx and premedullary cistern velocities are related to an early improvement of symptoms in patients with CM-1 syringomyelia who underwent PFD. The existence of a biphasic pulsatile systolic–diastolic CSF pattern inside the syrinx validates the “transmedullary” theory about the syringogenesis.

Objective: Although stroke guidelines recommend antiplatelets be started 24 hoursafter tissue plasminogen activator (tPA), select mechanical thrombectomy (MT)patients with luminal irregularities or underlying intracranial atherosclerotic diseasemay benefit from earlier antiplatelet administration.Methods: We explore the safety of early (< 24 hours) post-tPA antiplatelet use byretrospectively reviewing patients who underwent MT and stent placement for acuteischemic stroke from June 2015 to April 2018 at our institution.Results: Six patients met inclusion criteria. Median presenting and pre-operativeNational Institutes of Health Stroke Scale scores were 14 (Interquartile Range [IQR]5.5-17.3) and 16 (IQR 13.7-18.7), respectively. Five patients received standard intravenous(IV) tPA and one patient received intra-arterial tPA. Median time from symptomonset to IV tPA was 120 min (IQR 78-204 min). Median time between tPA and antiplateletadministration was 4.9 hours (IQR 3.0-6.7 hours). Clots were successfullyremoved from the internal carotid artery (ICA) or middle cerebral artery (MCA) in 5patients, the anterior cerebral artery (ACA) in one patient, and the vertebrobasilarjunction in one patient. All patients underwent MT before stenting and achievedthrombolysis in cerebral infarction 2B recanalization. Stents were placed in the ICA(n=4), common carotid artery (n=1), and basilar artery (n=1). The median time fromstroke onset to endovascular access was 185 min (IQR 136-417 min). No patientsexperienced symptomatic post-procedure intracranial hemorrhage (ICH). Medianmodified Rankin Scale score on discharge was 3.5.Conclusions: Antiplatelets within 24 hours of tPA did not result in symptomatic ICHin this series. The safety and efficacy of early antiplatelet administration after tPA inselect patients following mechanical thrombectomy warrants further study.

Objective: While intraoperative neuromonitoring (IONM) has been increasingly used in spine surgery to have a real-time evaluation of the neurological injury, we aim here to assess its utility during anterior lumbar interbody fusion (ALIF) and its association with postoperative neurological deficit.Summary of Background Data: ALIF is a beneficial surgical approach for patients with degenerative disease of the lower lumbar spine who would benefit from increased lordosis and restoration of neuroforaminal height. One risk of ALIF is iatrogenic nerve root injury. IONM may be useful in preventing this injury. Materials and Methods:We performed a retrospective cohort study of 111 consecutive patients who underwent ALIF at a tertiary care academic center by 6 spine surgeons. We aimed to describe the association between IONM, postoperative weakness, and factors that predispose our center to using IONM. Results:The 111 patients had a median age of 62 years [interquartile range (IQR): 53-69 y]. Neuromonitoring was used in 67 patients (60.3%) and not used in 44 patients. Seven neuromonitoring patients had IONM changes during the surgery. Three of these patients' surgeries featured intraoperative adjustments to reduce iatrogenic neural injury. The IONM cohort underwent significantly more complex procedures [5 levels (IQR: 3-7) vs. 2 levels (IQR: 2-5), P = 0.001]. There was no difference in rates of new or worsened postoperative weakness (IONM: 20.6%, non-IONM: 20.5%). Conclusions:We demonstrate evidence of the potential benefits of IONM for patients undergoing ALIF. Intraoperative changes in neuromonitoring signals resulted in surgical adjustments that likely prevented neurological deficits postoperatively. IONM was protective so that more complex surgeries did not have a higher rate of postoperative weakness.