Machine learning for outcome prediction of neurosurgical aneurysm treatment: Current methods and future directions.

INTRODUCTION: Machine learning algorithms have received increased attention in neurosurgical literature for improved accuracy over traditional predictive methods. In this review, the authors sought to assess current applications of machine learning for outcome prediction of neurosurgical treatment of intracranial aneurysms and identify areas for future research. METHODS: A PRISMA-compliant systematic review of the PubMed, MEDLINE, and EMBASE databases was conducted for all studies utilizing machine learning for outcome prediction of intracranial aneurysm treatment. Patient characteristics, machine learning methods, outcomes of interest, and accuracy metrics were recorded from included studies. RESULTS: 16 studies were ultimately included in qualitative synthesis. Studies primarily analyzed angiographic outcomes, functional outcomes, or complication prediction using clinical, radiological, or composite variables. The majority of included studies utilized supervised learning algorithms for analysis of dichotomized outcomes. CONCLUSIONS: Commonly included variables were demographics, presentation variables (including ruptured or unruptured status), and treatment used. Areas for future research include increased generalizability across institutions and for smaller datasets, as well as development of front-end tools for clinical applicability of published algorithms.

Digital Subtraction Angiography May Reduce the Rate of Radiographic Hemorrhage in Stereoelectroencephalography.

OBJECTIVE: To study the effect of preoperative digital subtractive angiography (DSA) for planning stereoelectroencephalography (sEEG) electrode trajectories on the rate of postoperative radiographic hemorrhage. METHODS: A retrospective, single-center observational study was conducted examining every sEEG implantation consisting of 72 implantations of 1028 total electrodes with each patient having received a preoperative planning DSA. Postimplant imaging was analyzed for the presence of hemorrhage. Postoperative computed tomography were then merged and coregistered with preoperative DSA to determine if a collision or near-miss (within 1 mm) occurred between the perihemorrhage electrodes and a vessel. Statistical analysis was then conducted. RESULTS: Six patients (8.3%) had hemorrhage seen on computed tomography with a bleeding rate of 0.6% per electrode. Five patients were asymptomatic (6.94%) and one symptomatic (1.39%). One patient suffered permanent neurologic deficits, and there have been zero deaths. In the hemorrhage group, there were 3 subdural, 2 subarachnoid, and 2 intraparenchymal. All subdural and subarachnoid hemorrhages had electrodes that were found to collide or near-miss a vessel when compared with preoperative DSA. Half of the intraparenchymal hemorrhages had no obvious vessel in proximity to the electrodes. Our data show that preoperative DSA is a viable screening test and portends a 94.7% sensitivity and 53.6% specificity for predicting post operative radiographic hemorrhage. CONCLUSIONS: Analysis of our sEEG series reveals a substantially lower rate of postimplant hemorrhage when compared with the recent cohort studies. Our data indicate that preoperative DSA may be efficacious in reducing the incidence of sEEG postimplant hemorrhages.

Internal Neurolysis for the Treatment of Trigeminal Neuralgia: A Systematic Review.

INTRODUCTION: Trigeminal neuralgia (TN) remains a challenging disease with debilitating symptoms and variable efficacy in terms of treatment options. Microvascular decompression (MVD) with internal neurolysis (IN) is an alternative treatment that might benefit patients but has limited understanding. We performed a systematic review of IN for the treatment of TN. METHODS: Studies from 2000 to 2021 that had assessed IN for TN were aggregated and independently reviewed. RESULTS: A total of 520 patients in 12 studies were identified, with 384 who had undergone IN (mean age, 53.8 years; range, 46-61.4 years; mean follow-up, 36.5 months). Preoperative symptoms had been present for ∼55.0 months before treatment, and pain was predominantly in V2 and V3 (26.8%), followed by other distributions. Of the patients, 83.7% (range, 72%-93.8%) had had an excellent to good outcome (Barrow Neurological Institute pain scale score [BNI-PS], I-II). The pain outcomes at 1 year were excellent for 58%-78.4%, good or better for 77%-93.75%, and fair or better for 80%-93.75% of the patients. On average, facial numbness after IN was experienced by 96% of the patients. However, at follow-up, facial numbness remained in only 1.75%-10%. Most of the remaining numbness was not significantly distressing to the patients. Subgroup comparisons of IN versus recurrent MVD, IN versus radiofrequency ablation, the effects of IN in the absence of vascular compression, and IN with and without MVD were also evaluated. CONCLUSIONS: IN represents a promising surgical intervention for TN in the absence of vascular compression and for potential cases of recurrence. Complications were limited in general but require further study.

The Life and Death of Lord Nelson: The Leader, the Patient, the Legend.

Admiral Lord Horatio Nelson is perhaps the most renowned naval commander, who allowed Britain to have dominion over the sea for 100 years after his victory at the Battle of Trafalgar. He was able to do so despite suffering from a multitude of communicable diseases and traumatic injuries, including the functional loss of his right eye, amputation of his right arm, scalp laceration, head injury, and finally a spinal injury. These injuries had permanent consequences but did not stop him from leading the charge and allowing the British to defeat the French and Spanish fleets in the decisive Battle of Trafalgar.

Neurosurgical Evaluation for Patients with Chronic Lower Back Pain.

PURPOSE OF REVIEW: Chronic low back pain (CLBP) is a major cause of disability in the USA, and it affects approximately 1 in 4 Americans. CLBP patients are commonly referred to or seek out neurosurgical evaluations and opinions for treatment and management. RECENT FINDINGS: Literature shows that only a minority of patients with CLBP may benefit from a surgical procedure. These patients that present to clinic often have been ailing for a considerable amount of time and are eager for effective treatment to alleviate pain. However, determining if a patient with CLBP is a surgical candidate is predicated upon having no success of pain relief with non-operative management. Patients with CLBP require thorough and adequate imaging, clinical exam, and diagnostic evaluation. When adequate non-operative management was provided, and proven fruitless, the patient may be considered an operative candidate. In this manuscript, a framework is presented for workup and evaluation of patients with CLBP.

Internal Neurolysis with and without Microvascular Decompression for Trigeminal Neuralgia: Case Series.

OBJECTIVE: Microvascular decompression (MVD) has remained the first-line surgical treatment of trigeminal neuralgia when an offending vessel can be identified that is causing neurovascular compression. However, patients without neurovascular compression can either develop trigeminal neuralgia or recurrence after MVD. In addition, patients with venous and less severe arterial compression have been shown to have reduced efficacy after MVD. Internal neurolysis is a surgical technique used to separate the fascicles of the trigeminal nerve and might be a good option for patients with trigeminal neuralgia but without vascular compression. METHODS: A retrospective, institutional review board-approved medical record review was performed of adult patients with trigeminal neuralgia who had undergone internal neurolysis. The search resulted in 32 patients who had been treated from 2016 to 2019. The Barrow Neurological Institute (BNI) pain intensity scale and hypesthesia scale (HS) were used to determine the outcomes. RESULTS: The average follow-up was 20 months (range, 3-40 months). The postoperative outcomes showed a BNI pain intensity scale score of I for 50%, with excellent control in 56%, successful control in 78%, adequate control in 94%, and poor control in 6%. Significantly more patients without previous treatment had had successful pain control (95% vs. 54%). Six patients (19%) experienced pain recurrence and were significantly more likely to experience pain recurrence compared with patients without a previous procedure (39% vs. 5%). The overall BNI-HS score postoperatively was I for 28%, II for 69%, and III for 3%. CONCLUSIONS: Internal neurolysis with and without MVD has shown efficacy in treating trigeminal neuralgia in carefully selected patients.

Atypical presentation of spinal intramedullary astrocytoma in a patient presenting with isolated signs of intracranial hypertension.

INTRODUCTION: Intramedullary spinal tumors are rare entities that typically present with signs of spinal cord dysfunction including myelopathy, weakness, hypoesthesia, or bladder dysfunction. However, they can present in more insidious ways without signs of spinal cord dysfunction, as we will discuss in this case. Our patient presented with isolated signs of intracranial hypertension including headache and progressive vision loss. Although idiopathic intracranial hypertension (IIH) is significantly more common than spinal cord tumors, a full evaluation to rule out other diagnoses should always occur, as this is an exclusionary diagnosis. CASE PRESENTATION: We describe an interesting case of an obese, middle-aged female who presented with signs and symptoms of elevated intracranial pressure (ICP) including progressive headache, visual changes, and papilledema. This led to a presumptive diagnosis of idiopathic intracranial hypertension (IIH). However, a careful review of her cerebrospinal fluid (CSF) analysis revealed a significantly elevated protein level. This prompted a more thorough workup, including a spinal MRI, that revealed an intramedullary astrocytoma. On her presenting physical exam, she had no upper or lower motor signs, no weakness, and no pathological reflexes. DISCUSSION: In the evaluation of a patient with isolated signs of increased ICP concerning for IIH, it is important to conduct a thorough workup as this remains a diagnosis of exclusion. Many intracranial and intraspinal pathologies can manifest with similar vague neurological symptoms and masquerade as a more benign disease as shown in our patient who, unfortunately, died from a spinal astrocytoma.

Robot-Assisted Instrumented Fusion of a T8-9 Extension Distraction Fracture and Epidural Hematoma Evacuation: 2-Dimensional Operative Video.

The utilization of robotics has been gaining increased popularity in spine surgery. It can be used to assist in pedicle screw insertion when anatomy is complex in deformity surgery, but is also helpful in degenerative spine as it can minimize tissue dissection and fluoroscopy use.1-6 We present an operative video that demonstrates the use of a robotic system (Globus Excelsius GPS, Audubon, Pennsylvania) for thoracic instrumentation in an unstable fracture. The patient we present is a 64-yr-old male who sustained a T8-9 distraction extension fracture after falling down a flight of stairs. His computed tomography (CT) scan showed ossification of the anterior longitudinal ligament making ankylosing spondylitis the likely underlying condition.7,8 His magnetic resonance imaging showed an epidural hematoma extending from T7 to T11. Due to the unstable nature of this fracture and the presence of the hematoma, informed consent was obtained and the patient underwent thoracic pedicle screw fixation from T7 to T11 and laminectomy for hematoma evacuation. A preoperative CT was done for screw trajectory planning. Paraspinal muscle dissection was limited to the hematoma level to allow for laminectomy and evacuation. After registration of the patient to the robotic system using C-arm fluoroscopy, pilot burr holes are drilled using a rigid robotic arm and with optical tracking in real time. This reduces the degrees of freedom and allows for higher precision of screw placement. To the authors' knowledge, this video is the first one to show the utilization of robotics for thoracic instrumentation in an acute fracture.

Waves of Pain Relief: A Systematic Review of Clinical Trials in Spinal Cord Stimulation Waveforms for the Treatment of Chronic Neuropathic Low Back and Leg Pain.

In the United States, chronic low back pain affects up to 37% of adults and is a multibillion dollar health care expenditure. Spinal cord simulation (SCS) has been established as an effective treatment alternative for chronic neuropathic low back and leg pain, especially for patients with failed back surgery syndrome or chronic regional pain syndrome. The field of SCS has rapidly advanced such that analgesia can now be achieved through numerous different waveforms, each claiming to offer improved outcomes. These waveforms include traditional paresthesia-based SCS (<100 Hz), paresthesia-free high-frequency SCS (5-10 kHz), burst SCS, and subperception SCS (1-5 kHz). Level 1 evidence critically evaluating the efficacy of these different waveforms is lacking. We conducted a systematic review of the literature in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify all randomized controlled trials of SCS in the treatment of chronic neuropathic low back and leg pain, failed back surgery syndrome, or chronic regional pain syndrome. Of 38 eligible studies reviewed, 13 randomized controlled trials were finally included in our systematic review. We reviewed evidence from randomized controlled trials in the field of SCS that have established paresthesia-based SCS, paresthesia-free high-frequency SCS, burst SCS, and subperception SCS as viable treatment options for chronic neuropathic low back and leg pain. We critically evaluated evidence that claims to support the use of one waveform over another and reviewed the literature on patient preference for different waveforms.

Head injury in heroes of the Civil War and its lasting influence.

The Civil War era was an age-defining period in the history of the United States of America, the effects of which are still seen in the nation today. In this era, the issue of head injury pervaded society. From the president of the United States, Abraham Lincoln, to the officers and soldiers of the Union and Confederate armies, and to the population at large, head injury and its ramifications gripped the nation. This article focuses on 3 individuals: Major General John Sedgwick, First Lieutenant Alonzo Cushing, and Harriet Tubman, as examples of the impact that head injury had during this era. These 3 individuals were chosen for this article because of their lasting legacies, contributions to society, and interesting connections to one another.

The War of Independence: a surgical algorithm for the treatment of head injury in the continental army.

The American Revolution was a gruesome war that resulted in the independence of the United States of America from the British crown and countless casualties to both belligerents. However, from these desperate times, the treatment of traumatic head injury was elucidated, as were the origins of American neurosurgery in the 18th century. During the war, the surgical manual used by military field surgeons was titled Plain Concise Practical Remarks on the Treatment of Wounds and Fractures, by Dr. John Jones. This manual explains the different types of cranial injuries understood at that time as well as the relevant surgical treatment. This article seeks to review the surgical treatment of head injury in the Revolutionary War as outlined by Dr. Jones's manual.

SLAM: Stereotactic Radiosurgery of Large Arteriovenous Malformations: Meta-analysis of Hemorrhage in High-Grade Pollock-Flickinger Arteriovenous Malformations.

BACKGROUND: The prognosis of arteriovenous malformations (AVMs) after treatment has been predicted largely by 2 grading scales: the Spetzler-Martin and Pollock-Flickinger. Although there are studies that examine the rate of hemorrhage with the Spetzler-Martin scale, there have not been studies examining hemorrhage in which the Pollock-Flickinger score was used. The annual hemorrhage rate after radiosurgery of Pollock-Flickinger AVM scores >2 is analyzed. METHODS: Literature search for radiosurgery of large AVMs from January 1, 2000 to June 1, 2014 was conducted. Articles were examined for individual patient data and aggregate patient data that reported hemorrhage rates and mortality. Patients were only included if they had an AVM score ≥2. RESULTS: Annual AVM hemorrhage rate after radiosurgery for all patients (n = 673) was 3.22% (99.3 hemorrhages, 3080.5 follow-up years, 95% confidence interval [95% CI] 2.64%-3.89%). Mortality rate from hemorrhage was 40.08% (95% CI 31.21%-49.90%). A total of 203 patients presented with hemorrhage and 395 did not. In patients with first-time hemorrhage, the annual hemorrhage rate was 3.53% (95% CI 2.66%-4.77%). The annual hemorrhage rate of those with hemorrhagic presentation was 6.10% (95% CI 4.65%-8.07%). The odds ratio comparing re-hemorrhage rate versus first-time hemorrhage is 1.768 (95% CI 1.1571-2.7014, P = 0.0084). Complete obliteration of all AVMs was equal to 33.27% (95% CI, 29.25%-37.54%). CONCLUSIONS: The annual hemorrhage rate in AVMs with scores >2 treated with radiosurgery was comparable with baseline rupture rates reported for untreated AVMs. With further stratification by hemorrhagic versus nonhemorrhagic presentation, the subsequent annual hemorrhage rates are similar to their respective natural histories. Considering the mortality rate from hemorrhage at 40.08% (95% CI, 35.54%-44.62%), the consequences of radiosurgical treatment of large AVMs is significantly worse than the reported 10%-30% fatality rate from hemorrhage of an untreated AVM. Additionally, the overall mortality rate was 6.24% however the percentage of mortalities from hemorrhage was 97.62%.

The War of Independence: a surgical algorithm for the treatment of head injury in the continental army.

The American Revolution was a gruesome warthat resulted in the independence of the United States of America from the British crown and countless casualties to both belligerents. However, from these desperate times, the treatment of traumatic head injury was elucidated, as were the origins of American neurosurgery in the 18th century. During the war, the surgical manual used by military field surgeons was titled Plain Concise Practical Remarks on the Treatment of Wounds and Fractures, by Dr. John Jones. This manual explains the different types of cranial injuries understood at that time as well as the relevant surgical treatment. This article seeks to review the surgical treatment of head injury in the Revolutionary War as outlined by Dr. Jones's manual.

Joseph Warren: a discussion of his life and analysis of his death.

As his fellow soldiers ran past him, Joseph Warren stood bravely on Bunker Hill. It was June 17, 1775, and British troops were fighting the colonists in one of the early battles of the American Revolution. The British had already attempted two major assaults that day, and the third would end with Warren's death. He was a medical doctor, public figure, and general who spent his life and last living moments fighting for freedom for the American colonists. After the battle, there was much confusion about what had happened to Joseph Warren. Some thought he had survived the battle; other accounts differed on how exactly he had died. The details of the events on Bunker Hill remained a mystery until the following year, when Paul Revere helped identify Warren's body by the false teeth that had been implanted years earlier. Warren's remains showed that his head had been struck by a bullet. Analysis of the skull helped to sift through the differing tales of Warren's death and thus unveil the truth about what occurred that day. The smaller bullet wound in the left maxilla suggests that he was not shot while retreating with the rest of the soldiers. The larger exit wound in the right occiput illustrates that the bullet's trajectory crossed the midline of the brain and most likely injured the brainstem. Therefore, contrary to rumors that circulated at the time, Joseph Warren most likely was killed instantly at the Battle of Bunker Hill while heroically facing his enemy.

Famous head injuries of the first aerial war: deaths of the "Knights of the Air".

World War I advanced the development of aviation from the concept of flight to the use of aircraft on the battlefield. Fighter planes advanced technologically as the war progressed. Fighter pilot aces Francesco Baracca and Manfred von Richthofen (the Red Baron) were two of the most famous pilots of this time period. These courageous fighter aces skillfully maneuvered their SPAD and Albatros planes, respectively, while battling enemies and scoring aerial victories that contributed to the course of the war. The media thrilled the public with their depictions of the heroic feats of fighter pilots such as Baracca and the Red Baron. Despite their aerial prowess, both pilots would eventually be shot down in combat. Although the accounts of their deaths are debated, it is undeniable that both were victims of traumatic head injury.

Pierre Curie: the anonymous neurosurgical contributor.

Pierre Curie, best known as a Nobel Laureate in Physics for his co-contributions to the field of radioactivity alongside research partner and wife Marie Curie, died suddenly in 1906 from a street accident in Paris. Tragically, his skull was crushed under the wheel of a horse-drawn carriage. This article attempts to honor the life and achievements of Pierre Curie, whose trailblazing work in radioactivity and piezoelectricity set into motion a wide range of technological developments that have culminated in the advent of numerous techniques used in neurological surgery today. These innovations include brachytherapy, Gamma Knife radiosurgery, focused ultrasound, and haptic feedback in robotic surgery.