Implantable Intracranial Pressure Sensor with Continuous Bluetooth Transmission via Mobile Application.

Hydrocephalus is a clinical disorder caused by excessive cerebrospinal fluid (CSF) buildup in the ventricles of the brain, often requiring permanent CSF diversion via an implanted shunt system. Such shunts are prone to failure over time; an ambulatory intracranial pressure (ICP) monitoring device may assist in the detection of shunt failure without an invasive diagnostic workup. Additionally, high resolution, noninvasive intracranial pressure monitoring will help in the study of diseases such as normal pressure hydrocephalus (NPH) and idiopathic intracranial hypertension (IIH). We propose an implantable, continuous, rechargeable ICP monitoring device that communicates via Bluetooth with mobile applications. The design requirements were met at the lower ICP ranges; the obtained error fell within the idealized ±2 mmHg margin when obtaining pressure values at or below 20 mmHg. The error was slightly above the specified range at higher ICPs (±10% from 20-100 mmHg). The system successfully simulates occlusions and disconnections of the proximal and distal catheters, valve failure, and simulation of A and B ICP waves. The mobile application accurately detects the ICP fluctuations that occur in these physiologic states. The presented macro-scale prototype is an ex-vivo model of an implantable, rechargeable ICP monitoring system that has the potential to measure clinically relevant ICPs and wirelessly provide accessible and continuous data to aid in the workup of shunt failure.

Interhemispheric Approach.

The interhemispheric approach is the natural route to reach the parafalcine and paraventricular structures through the interhemispheric fissure. In this chapter, we report the main anterior and posterior corridors of the interhemispheric approach.

Prevention of Neurological Deficit With Intraoperative Neuromonitoring During Anterior Lumbar Interbody Fusion.

STUDY DESIGN: This was a retrospective cohort 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.

Three-Dimensional Volumetric Assessment of Resected Gliomas Assisted by Horos Imaging Software: Video Case Series of Postoperative Tumor Analyses.

Horos (LGPL 3.0; GNU Lesser General Public License, Version 3) is a free, open-source medical image viewer with a user-friendly interface and three-dimensional (3D) volumetric rendering capabilities. We present the use of Horos software as a postoperative tool for residual tumor volume analysis in children with high-grade gliomas (HGG). This is a case series of two pediatric patients with histologically confirmed high-grade gliomas who underwent tumor resection as definitive treatment from June 2011 to June 2019. Volumetric data and extent of resection were obtained via region of interest-based 3D analysis using Horos image-processing software. Horos software provides increased accuracy and confidence in determining the postoperative volume and is useful in assessing the impact of residual volume on outcomes in patients with high-grade gliomas. Horos software is a highly effective means of volumetric analysis for the postoperative analysis of residual volume after maximal safe resection of high-grade gliomas in pediatric patients.

Pulsatile cerebrospinal fluid dynamics in Chiari I malformation syringomyelia: Predictive value in posterior fossa decompression and insights into the syringogenesis.

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 1st 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.

Anterolateral approach for subaxial vertebral artery decompression in the treatment of rotational occlusion syndrome: results of a personal series and technical note.

OBJECTIVES: To report the results of a retrospective series and a technical note about the anterolateral approach for the treatment of the rotational occlusion syndrome (ROS) involving the subaxial V2 segment of the vertebral artery (VA). METHODS: We retrospectively reviewed the data of a cohort of patients that underwent an anterolateral approach to decompress the VA as they suffered from ROS secondary to a subaxial compression. A dynamic study with ultrasonography, CT, MRI, and catheter-based angiography were obtained in all cases. Severe symptomatology and cerebellar-brainstem strokes were indications for surgery. The anterolateral approach involved a pre-sternocleidomastoid precarotid exposure. The retro-longus colli and pre-scalenic corridors were used to access the C5-C6 and C3-C4 segment, respectively, and to perform the decompression. RESULTS: Twelve patients were treated. Recurrent drop attacks were present in all cases. Osteophytes at C5 and C6 were the most common causes of subaxial VA compression. Anterior decompression stand-alone was performed in all but 1 patient. A recurrent laryngeal nerve palsy and a numbness of the C5 nerve root were the only complications observed, both transient. A satisfactory untethering of the VA with a complete recovery was achieved in all patients, apart from those with severe infratentorial strokes. DISCUSSION READ: Anterolateral approach allows for an effective and safe treatment of the ROS involving the subaxial portion of the VA. Retro-longus colli and pre-scalenic corridors, developed through a precarotid exposure, have an anatomical rationale in decreasing the risks of complications. Decompression stand-alone is adequate in almost the totality of cases.

Antiplatelet therapy within 24 hours of tPA: lessons learned from patients requiring combined thrombectomy and stenting for acute ischemic stroke.

OBJECTIVE: Although stroke guidelines recommend antiplatelets be started 24 hours after tissue plasminogen activator (tPA), select mechanical thrombectomy (MT) patients with luminal irregularities or underlying intracranial atherosclerotic disease may benefit from earlier antiplatelet administration. METHODS: We explore the safety of early (<24 hours) post-tPA antiplatelet use by retrospectively reviewing patients who underwent MT and stent placement for acute ischemic stroke from June 2015 to April 2018 at our institution. RESULTS: Six patients met inclusion criteria. Median presenting and pre-operative National 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 symptom onset to IV tPA was 120 min (IQR 78-204 min). Median time between tPA and antiplatelet administration was 4.9 hours (IQR 3.0-6.7 hours). Clots were successfully removed from the internal carotid artery (ICA) or middle cerebral artery (MCA) in 5 patients, the anterior cerebral artery (ACA) in one patient, and the vertebrobasilar junction in one patient. All patients underwent MT before stenting and achieved thrombolysis 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 from stroke onset to endovascular access was 185 min (IQR 136-417 min). No patients experienced symptomatic post-procedure intracranial hemorrhage (ICH). Median modified Rankin Scale score on discharge was 3.5. CONCLUSIONS: Antiplatelets within 24 hours of tPA did not result in symptomatic ICH in this series. The safety and efficacy of early antiplatelet administration after tPA in select patients following mechanical thrombectomy warrants further study.

Simulator Training for Endovascular Neurosurgery.

Simulation-based training has become common practice across medical specialties, especially for learning complex skills performed in high-risk environments. In the field of endovascular neurosurgery, the demand for consequence- and risk-free learning environments led to the development of simulation devices valuable for medical trainees. The goal of this protocol is to provide instructive guidelines for the use of an endovascular neurosurgery simulator in an academic setting. The simulator provides trainees with the opportunity to receive realistic feedback on their knowledge of anatomy, as well as haptic feedback indicative of their success in handling the catheter-based systems without negative consequences. The utility of this specific protocol in relation to other neuroendovascular training modalities is also discussed.

Early Decompressive Craniectomy as Management for Severe Traumatic Brain Injury in the Pediatric Population: A Comprehensive Literature Review.

BACKGROUND: Severe traumatic brain injuries (TBIs) are a principal cause of neurologic dysfunction and death in the pediatric population. After medical management, the second-tier treatment is decompressive craniectomy in cases of intractable intracranial pressure (ICP) elevation. This literature review offers evidence of early (within 24 hours) and ultraearly (6-12 hours) decompressive craniectomy as an effective form of management for severe TBI in the pediatric population. METHODS: We conducted a literature review of articles published from 1996 to 2019 to elucidate neurologic outcomes after early decompressive craniectomy in pediatric patients who suffered a severe TBI. Time to decompressive craniectomy and neurologic outcomes were recorded and reported descriptively. Qualitative data describe clinically important correlations between pre- and postoperative ICP levels and improved postoperative neurologic outcomes. RESULTS: Seventy-eight patients were included in this study. The median age of patients at diagnosis was 10 years of age (range, 1 months to 19 years). Median admission Glasgow Coma Scale score was 5 (range, 3-8). Time to decompressive craniectomy ranged from 1 to 24 hours. Median peak preoperative ICP was 40 (range, 3-90; n = 49). Median postoperative ICP was 20 (range, 0-80; n = 33). Median Glasgow Outcome Scale (GOS) score at discharge was 2 (range, 1-5; n = 11). Median GOS score at 3- and 6-month follow-up was 3 (range, 1-5; n = 11). Median GOS score at 7- to 23-month follow-up was 4 (range, 1-5; n = 29). Median GOS score at 24- to 83-month follow-up was 4 (range, 1-5; n = 31). Median modified Rankin Scale score at discharge was 3 (range, 2-4; n = 6). Median modified Rankin Scale score at 6- to 48-month follow-up was 2 (range, 0-3; n = 6). Median Rancho Los Amigos Scale (RLAS) score at discharge was 6 (range, 4-8; n = 5). Median RLAS score at 6-month follow-up was 10 (range, 8-10; n = 5). CONCLUSIONS: Early (within 24 hours), with consideration of ultraearly (within 6-12 hours), decompressive craniectomy for severe TBI should be offered to pediatric patients in settings with refractory ICP elevation. Reduction of ICP allows for prompt disruption of pathophysiologic cascades and improved neurologic outcomes.

Onyx Embolization of a Distal Middle Cerebral Artery Pseudoaneurysm in a Five-Week-Old: A Case Report and Review of Current Treatment Options.

Intracranial pseudoaneurysms secondary to traumatic birth are a rare finding in infants. Definitive diagnosis of such findings is challenging, and no standard management is delineated for management of pseudoaneurysms in the pediatric population. Commonly attempted treatments include endovascular embolization or surgical clipping. A 5-week-old female presented with a two day history of right hand focal seizures. The patient was found to have a dysplastic superficial intra-axial aneurysm arising from the distal left middle cerebral artery (MCA) branch in the setting of a left posterior frontal lobe hemorrhage noted on brain magnetic resonance imaging/magnetic resonance angiography (MRI/MRA). The patient underwent diagnostic cerebral angiogram demonstrating a left distal MCA pseudoaneurysm, which was treated with Onyx embolization. Post-embolization period was complicated by recurrent left central localized seizures and a left hemispheric temporoparietal hemorrhagic infarction. The patient was managed on levetiracetam, phenytoin, phenobarbital with stable seizure control. Herein, we highlight the youngest case to date of a 5-week-old infant with a left distal MCA pseudoaneurysm treated with Onyx embolization. Pseudoaneurysmal incidence, diagnosis and accepted management is discussed.