-BACKGROUND: Neurocritical management of aneu-rysmal subarachnoid hemorrhage focuses on delayed ce-rebral ischemia (DCI) after aneurysm repair.-METHODS: This study conceptualizes the pathophysiology of cerebral ischemia and its management using a brain oxy-gen -directed protocol (intracranial pressure [ICP] control, eubaric hyperoxia, hemodynamic therapy, arterial vasodila-tion, and neuroprotection) in patients with subarachnoid hemorrhage, undergoing aneurysm clipping (n = 40).-RESULTS: The brain oxygen -directed protocol reduced LbO2 (PbtO2 [partial pressure of brain tissue oxygen] <20 mm Hg) from 67% to 15% during acute brain attack (<24 hours of ictus), by increasing PbtO2 from 11.31 +/- 9.34 to 27.85 +/- 6.76 (P< 0.0001) and then to 29.09 +/- 17.88 within 72 hours. Day-after-bleed, FiO2 change, ICP, hemoglobin, and oxygen saturation were pre-dictors for PbtO2 during early brain injury. Transcranial Doppler -ltrasonography velocities (>20 cm/second) increased at day 2. During DCI caused by territorial sonographic vasospasm (TSV), middle cerebral artery mean velocity (Vm) increased from 45.00 +/- 15.12 to 80.37 +/- 38.33/second by day 4 with concomitant PbtO2 reduction from 29.09 +/- 17.88 to 22.66 +/- 8.19.Peak TSV (days 7-12) coincided with decline in PbtO2. Nicardipine mitigated LbO2 during peak TSV, in contrast to n imodipine, with survival benefit (P < 0.01). Intravenous and cisternal nicardipine combination had survival benefit (Cramer F = 0.43 and 0.327; G2 = 28.32; P< 0.001). This study identifies 4 zones of LbO2 during survival benefit (Cramer F = 0.43 and 0.3) TSV, uncompensated; global cerebral ischemia, compen-sated, and normal PbtO2. Admission Glasgow Coma Scale score (not increased ICP) was predictive of low PbtO2 (b= 0.812, R2 = 0.661, F1,30 = 58.41; P< 0.0001) during early brain injury. Coma was the only credible predictor for mortality (odds ratio, 7.33/>4.8*; c2 = 7.556; confidence interval, 1.70-31.54; P < 0.01) followed by basilar aneurysm, poor grade, high ICP and LbO2 during TSV. Global cerebral ischemia occurs immediately after the ictus, persisting in 30% of patients despite the high therapeutic intensity level, superimposed by DCI during TSV. -CONCLUSIONS: We propose implications for clinical practice and patient management to minimize cerebral ischemia.

Abstract: Arteriovenous fistulae present in any of a number of characteristic locations in the brain, such as the ethmoidal region, the petrosal sinus, and the transverse sinus and torcula. The fistula is an abnormal connection between an artery and vein. While there are multiple accepted classification systems, the risk they represent to the patient depends primarily on the degree of reflux of the venous drainage back to the cortex of the brain. While the inflow and outflow may be very complex, isolation of the fistulous point where this abnormal connection occurs is the key to successful treatment. This may be achieved through either endovascular or open surgical techniques deoending on the anatomy.

Early recognition and differentiation of acute ischemic stroke from intracranial hemorrhage and stroke mimics and the identification of large vessel occlusion (LVO) are critical to the appropriate management of stroke patients. In this review, we discuss the current evidence and practices surrounding safe and efficient triage in the emergency room. As the indications of stroke intervention are evolving to further improve stroke care, focus has begun to revolve around recognition of LVO and provision of endovascular thrombectomy with or without the administration of tissue plasminogen activator. Systems of stroke care are being organized to achieve this goal without delay. Clinical history is important in determining time of onset or last known well time, but, alone or along with an examination, it cannot reliably predict an LVO or exclude intracranial hemorrhage and stroke mimics. The choice of imaging is influenced mainly by the duration of symptoms. On the basis of recent trials, patients presenting after the 6-h therapeutic window can be considered for endovascular thrombectomy if the computed tomographic or magnetic resonance perfusion imaging shows favorable findings. The Society of NeuroInterventional Surgery has established time metrics for each step of triage and initial management. Hospitals are required to develop multidisciplinary stroke teams and emergency protocols to meet these goals. There also needs to be coordination of the emergency medical services with the emergency facility of an appropriate stroke center (a primary stroke center, comprehensive stroke care center, or a thrombectomy-capable stroke center).

Here, the authors examined the factors involved in the volumetric progression of traumatic brain contusions. The variables significant in this progression are identified, and the expansion rate of a brain bleed can now effectively be predicted given the presenting characteristics of the patient.

OBJECTIVE Idiopathic intracranial hypertension (IIH) is a commonly occurring disease, particularly among young women of child-bearing age. The underlying pathophysiology for this disease has remained largely unclear; however, the recent literature suggests that focal outflow obstruction of the transverse sinus may be the cause. The purpose of this study was to report one group's early experience with transverse venous sinus stenting in the treatment of IIH and assess its effectiveness. METHODS The authors performed a retrospective chart review to identify patients who had undergone stenting of an outflow-obstructed transverse venous sinus for the treatment of IIH at Gates Vascular Institute between January 2015 and November 2017. Patient demographic data of interest included age, sex, BMI, and history of smoking, hypertension, obstructive sleep apnea, hormonal contraceptive use, and acetazolamide therapy. Each patient's presenting signs and symptoms and whether those symptoms improved with treatment were reviewed. The average opening lumbar puncture (LP) pressure preprocedure, average pressure gradient across the obstructed segment prior to stenting, treatment failure rate (need for shunt placement), and mean follow-up period were calculated. RESULTS Of the 18 patients who had undergone transverse venous stenting for IIH, 16 (88.9%) were women. The mean age of all the patients was 38.3 years (median 38 years). Mean BMI was 34.2 kg/m(2) (median 33.9 kg/m(2)). Presenting symptoms were headache (16 patients [88.9%]), visual disturbances (13 patients [72.2%]), papilledema (8 patients [44.4%]), tinnitus (3 patients [16.7%]), and auditory bruit (3 patients [16.7%]). The mean opening LP pressure preprocedure was 35.6 cm H2O (median 32 cm H2O). The mean pressure gradient measured proximally and distally to the area of focal obstruction within the transverse sinus was 16.5 cm H2O (median 15 cm H2O). Postprocedurally, 14 patients (77.8%) continued to have headaches; 6 (33.3%) continued to have visual disturbances. No patients continued to have auditory bruit (0%) or papilledema (0%). One patient (5.6%) had new-onset tinnitus postprocedure. Overall improvement of symptoms was noted in 16 patients (88.9%) postprocedure, with 1 patient (5.6%) requiring shunt placement and 2 other patients (11.1%) requiring postprocedural LP to monitor intracranial pressure to determine candidacy for further surgical interventions to treat residual symptoms. The mean duration of follow-up was 194.2 days. CONCLUSIONS Transverse sinus stenting is a rapidly developing technique that has shown good effectiveness and safety in the literature. Authors of the present study found that stenting a flow-obstructed transverse sinus in patients with IIH was a safe and effective way to treat the condition.

OBJECTIVE Early radiographic findings in patients with traumatic brain injury (TBI) have been studied in hopes of better predicting injury severity and outcome. However, prior attempts have generally not considered the various types of intracranial hemorrhage in isolation and have typically not excluded patients with potentially confounding extracranial injuries. Therefore, the authors examined the associations of various radiographic findings with short-term outcome to assess the potential utility of these findings in future prognostic models. METHODS The authors retrospectively identified 1716 patients who had experienced TBI without major extracranial injuries, and categorized them into the following TBI subtypes: subdural hematoma (SDH), traumatic subarachnoid hemorrhage, intraparenchymal hemorrhage (which included intraventricular hemorrhage), and epidural hematoma. They specifically considered isolated forms of hemorrhage, in which only 1 subtype was present. RESULTS In general, the presence of an isolated SDH was more likely to result in worse outcomes than the presence of other isolated forms of traumatic intracranial hemorrhage. Discharge to home was less likely and perihospital mortality rates were generally higher in patients with SDH. These findings were not simply related to age and were not fully captured by the admission Glasgow Coma Scale (GCS) score. The presence of SDH had a much higher sensitivity for poor outcome than the presence of other TBI subtypes, and was more sensitive for these poor outcomes than having a low GCS score (3-8). CONCLUSIONS In these ways, SDH was the most important finding associated with poor outcome, and the authors show that consideration of SDH, specifically, can augment age and GCS score in classification and prognostic models for TBI.

Background: Animals held in captivity tend to live longer than do their wild counterparts, and as such, are prone to developing age-related degenerative injuries.Here, we present a case of an adult female polar bear with symptomatic lumbar stenosis.There is a paucity of literature on large mammalian spine surgery, and anatomical differences between humans and other vertebrates must be taken into consideration.Case Description: A 24-year-old female polar bear residing at the zoo was found to have decreased motor function in her hind legs.Diagnostic myelography performed at the L7/S1 level demonstrated lumbar stenosis at L5/6 for which a laminectomy was performed.Postoperatively, she returned to premorbid functional level, with no apparent associated adverse sequelae.Conclusions: To our knowledge, this is the first reported case of spine surgery in a polar bear and demonstrates that neurosurgical diagnostic and operative techniques developed for humans can also be applied to large mammals with successful results.

BACKGROUND AND IMPORTANCE:Cerebrospinal fluid shunt placement is used to treat the various causes of hydrocephalus by redirecting the cerebrospinal fluid to the body, most commonly from the ventricle to the peritoneum. Distal catheter displacement from the peritoneal cavity can occur as a complication, necessitating reoperation. CLINICAL PRESENTATION:We report 2 such cases in obese patients involving retropulsion of the distal tubing. To address this complication, we implanted a T-connector to the distal catheter construct. CONCLUSION:This study supports the use of a T-connector catheter construct to decrease and prevent the possibility of distal peritoneal catheter retropulsion in cases of elevated intra-abdominal pressure, both prophylactically and in revisions.

We present an unusual case of a 59year old male patient who presented with acute, bilateral lower extremity weakness and was found to have non-traumatic spinal subarachnoid hemorrhage. Diagnostic workup including MRI and angiography revealed an aneurysm of the artery of Ademkiewicz. This was managed conservatively and the patient has had marked clinical improvement. We present the details of this unusual case as well as a literature review related to aneurysms of the artery of Ademkiewicz.

Introduction Superficial temporal artery pseudoaneurysms (STAP) are uncommon vascular lesions typically coinciding with blunt head trauma. Although hundreds of cases have been described (5,10), few have been reported in sports medicine journals. Diagnosis of STAP can be made clinically, presenting as painless masses at the site of injury. STAP can be confused with cysts, abscesses, hematomas, lipomas, and other dermal lesions (2) but can be primarily identified using duplex ultrasound (US) or computed tomography angiography (CTA). Point-of-care musculoskeletal US, a modality becoming more widely available in sports medicine clinics, provides safe and accurate diagnosis of STAP and can facilitate referral, treatment, and ultimately return to play for athletes (10). Timely diagnosis is critical as pseudoaneurysm rupture is the main cause of morbidity. We present the case of a 16-year-old high school lacrosse player who developed STAP after being struck by a lacrosse ball. Case Report A 16-year old teenage boy presented to our sports medicine clinic with a painless left frontotemporal subcutaneous mass. Four weeks prior, he was struck in his helmeted head by a lacrosse ball from a close-range shot. He developed an area of swelling and discoloration over the left forehead 10 to 15 min after impact. He did not experience any headache, dizziness, or light/noise sensitivity postinjury. Initially, his lesion was managed as a scalp hematoma, and conservative treatment consisting of ice and compression was recommended. His athletic trainer referred him after his lesion failed to resolve clinically. Examination showed a 1-cm × 1-cm mobile, firm, rubbery mass in the subcutaneous tissue overlying the left forehead (Fig. 1A). The mass was nontender and pulsatile, with no appreciable underlying bony step-off. No bruising or hyperpigmentation was seen. The patient was neurologically stable.Figure 1: (A) Exam reveals a 1-cm × 1-cm mobile, firm, rubbery mass in the subcutaneous tissue overlying the left forehead. (B) A long-axis 15-6 MHz US image of a hypoechogenic structure in the subgaleal soft tissue. (C) Long-axis 15-6 MHz color Doppler imaging demonstrates bidirectional flow through a hypoechogenic structure in the subgaleal soft tissue.Doppler US identified a hypoechogenic, pulsatile structure in the subgaleal soft tissue, whereas color Doppler displayed appreciable venous and arterial flow through the structure (Fig. 1B,C). CTA was recommended to allow assessment of both soft tissue and bony pathology given the traumatic nature of the injury. CTA confirmed a pseudoaneurysm of the frontal branch of the left superficial temporal artery (STA). Surgical exploration was performed. The course of the proximal STA branch feeding the aneurysm was identified using US. Proximal control of the STA was obtained in the subgaleal plane, and the pseudoaneurysm was identified as located in the galeal layer (Fig. 2A). Proximal and distal feeders were ligated and microsurgical resection of the aneurysm was accomplished (Fig. 2B). Histology confirmed a pseudoaneurysm with mural hemorrhages and proliferating inflammatory granulation tissue with hemosiderin deposits and a luminal thrombus. At 1-month follow-up, the athlete was cleared to return to collision sports.Figure 2: (A) Pseudoaneurysm of the frontal branch of the left STA was identified in the galeal layer. (B) Resection of the entire aneurysm sack.Discussion STAP remains the most common type of craniofacial traumatic aneurysms (8). Thomas Bartholin first documented a STAP lesion secondary to blunt trauma in 1644 (5). Subsequently, nearly 400 STAP cases have been reported (10). Since 1994, STAP has been reported with increasing frequency in sports (9). Most incidental causes involve a high-speed projectile that imparts a blow to the athlete's temporal fossa. To our knowledge, this is the first case report of STAP in a lacrosse player and one of few sport-related cases involving a helmeted athlete. STA is the most distal branch of the external carotid artery. It is vulnerable to trauma because of its superficial nature along the temple and proximity to the underlying bony structures. Trauma to this vessel can cause it to partially sever or contuse, leading to a pseudoaneurysm or arteriovenous fistula. Common symptoms of STAP include a solitary, painless mass, pulsations, headache, and often ear discomfort that occurs 2 to 6 wk after injury. Less frequent symptoms include visual disturbances, dizziness, pain, or hemorrhage (9). The diagnosis of STAP is initially made with a complete history and physical examination along with confirmatory imaging including color Doppler US, CTA, magnetic resonance angiography, or digital subtraction angiography (6). The most accurate, noninvasive modality to aid in diagnosis is duplex US (9), a dynamic point-of-care study that can be performed in an office setting. CTA evaluates the patency and position of the main trunk and distal branches of the STA, including the transverse facial, frontal, and parietal branches. Limitations of CTA include cost, radiation exposure, and the relative invasive nature of CTA compared to US. Treatment of STAP is considered when there is 1) a risk of spontaneous rupture, particularly in patients with continued risk of blunt trauma in this exposed area, 2) pain and tenderness, or 3) cosmetic deformity (9). Our patient displayed all these criteria. In most STAP, surgical resection is preferred, given that symptoms are mainly associated with the mass effect and local irritation caused by the aneurysm, and sacrifice of the temporal artery is associated with low morbidity. The procedure of choice is proximal and distal vessel ligation with aneurysm excision, performed utilizing local anesthesia and conscious sedation (3). Potential risks of surgery include infection, hemorrhage, injury to local anatomical structures, aneurysm recurrence, and atrophy/necrosis of the overlying scalp. Alternative treatments include simple methods such as prolonged local pressure (2) or angiography with embolization (7,10). After the lesion heals, patient education regarding the importance of utilizing protective headgear is paramount. After counseling, the athlete may return to full-contact activities without limitations. Regarding notable sport-related STAP, Campbell et al. (1) presented the first-documented athletic injuries in two separate unhelmeted ice hockey players struck by a puck in the side of the head resulting in a STAP or "puck aneurysm." Golden et al. (4) described two athletes who developed pseudoaneurysm after being struck in the frontal region of the scalp by a squash ball. Lastly, Romero et al. (9) documented a minor league baseball player who was struck in the head with a baseball as he was sliding into second base. Other sport-related cases include head-to-head collision in rugby, paintball- and softball-inflicted trauma, and contact with an opposing player's elbow in basketball (9). None of the case reports involving baseball, softball, or ice hockey documented athletes wearing a helmet upon sustaining their injury, illustrating the importance of proper helmet use/fit and the potential importance of chinstrap use for baseball and softball to reduce risk of helmet loss and consequent head injury. The authors declare no conflicts of interest and do not have any financial disclosures.

BACKGROUND:Management of penetrating cranial trauma remains a high acuity and imaging intense neurosurgical disorder. Imaging of vital structures, including angiography, is typically conducted to understand the proximity of vital structures in comparison to a foreign body and prepare for intraoperative complications such as hemorrhage. Preservation of function following initial injury in cases where minimal neurological deficit exists is essential.CASE DESCRIPTION:Here, we present a case using intraoperative computed tomography to assist in early detection and resolution of hemorrhage in the surgical management of an intact patient with self-inflicted penetrating cranial trauma.CONCLUSIONS:This method may aid in early detection of hemorrhage and prevention of consequential neurological deterioration or emergent need for secondary surgery.

INTRODUCTION: Annually in the United States, an estimated 1.7 million people experience traumatic brain injury (TBI), resulting in 1.4 million emergency department visits, 270 000 hospitalizations, and 53 000 deaths. The most common mass lesions associated with TBI are hematomas and contusions. Currently, there is no proven treatment protocol for contusion management. This retrospective study seeks to provide a more comprehensive assessment of the hemorrhagic progressions of contusions (HPC) by analyzing the rate at which contusions blossom depending on a variety of factors. METHODS: This retrospective study examined 492 patients with cerebral contusions from 2005 to 2013, who presented to a level 1 trauma center and had follow-up computed tomography (CT) <72 hours later. Change in contusion volume over time, expansion rate (ER), was recorded for all patients. RESULTS: Of the 492 patients, 73.6% experienced HPC with an average ER of 0.73 cm3 per hour. Patients were compared based on blood alcohol level (BAL) (n = 152; 30.4%), platelet transfusion (n = 47; 9.4%), and anticoagulation therapy (n = 36; 7.2%). Separate 1-way analysis of covariance revealed significant differences in mean ER for patients with elevated BAL (P = .032), transfused platelets (P < .001), and anticoagulation (P = .007). A multiple regression analysis revealed that age (P = .03), systolic blood pressure (P = .005), international normalized ratio (b = 1.003, t = 2.76, P = .007), new injury severity score (b = 0.02, t = 2.10, P = .03), BAL (b = 0.003, t = 2.10, P = .03), and initial size of contusion (b = −0.049, t = −2.65, P = .009) significantly predicted 35.9% of the variance in ER (P < .001). Sex and Glasgow Coma Scale were nonsignificant predictors of expansion. CONCLUSION: There are various factors that contribute to the rate at which cerebral contusions blossom over an acute time course. Understanding the relationship of intrinsic and modifiable aspects of the presenting patient can help predict the rate of expansion and highlight potential therapeutic interventions to improve TBI-associated mortality.

OBJECT Programmable shunts have a valuable role in the treatment of patients with hydrocephalus, but because a magnet is used to change valve settings, interactions with external magnets may reprogram these shunts. Previous studies have demonstrated the ability of magnetic toys and iPads to erroneously reprogram shunts. Headphones are even more ubiquitous, and they contain an electromagnet for sound projection that sits on the head very close to the shunt valve. This study is the first to look at the magnetic field emissions of headphones and their effect on reprogrammable shunt valves to ascertain whether headphones are safe for patients with these shunts to wear. METHODS In this in vitro study of the magnetic properties of headphones and their interactions with 3 different programmable shunts, the authors evaluated Apple earbuds, Beats by Dr. Dre, and Bose QuietComfort Acoustic Noise Cancelling headphones. Each headphone was tested for electromagnetic field emissions using a direct current gaussmeter. The following valves were evaluated: Codman Hakim programmable valve, Medtronic Strata II valve, and Aesculap proGAV. Each valve was tested at distances of 0 to 50 mm (in 5-mm increments) from each headphone. The exposure time at each distance was 1 minute, and 3 trials were performed to confirm results at each valve setting and distance. RESULTS All 3 headphones generated magnetic fields greater than the respective shunt manufacturer's recommended strength of exposure, but these fields did not persist beyond 5 mm. By 2 cm, the fields levels were below 20 G, well below the Medtronic recommendation of 90 G and the Codman recommendation of 80 G. Because the mechanism for the proGAV is different, there is no recommended gauss level. There was no change in gauss-level emissions by the headphones with changes in frequency and amplitude. Both the Strata and Codman-Hakim valves were reprogrammed by direct contact (distance 0 mm) with the Bose headphones. When a rotation component was added, all 3 headphones reprogrammed the Strata and Codman-Hakim valves at 0 mm. At all distances above 0 mm, the headphones did not affect the shunts. The proGAV valve was not affected by headphones at any distance. CONCLUSIONS Although all the headphones studied generated significant gauss fields at distances less than 5 mm, the programmable valve settings only changed at a distance of 0 mm (i.e., with direct contact). Given the subcutaneous location of the valve, the authors conclude that is highly unlikely that commercially available or customary headphones can contribute to the reprogramming of shunts.

Pseudotumor cerebri is characterized by headaches, visual field changes, papilledema and an elevated cerebrospinal fluid opening pressure without evidence of an intracranial mass. In the setting of failed medical therapy, surgical options such as ventriculoperitoneal shunts and optic nerve sheath fenestrations are considered. Recently, venous sinus stenting has emerged as a new treatment option for patients with pseudotumor cerebri. We review the role of cerebral venous sinus stenting in the management of patients with medically refractory pseudotumor cerebri. Although long- term studies are needed in this field, the current reports indicate a favorable outcome for preventing vision loss and symptom control.

Predictive modeling of emergent behavior, inherent to complex physiological systems, requires the analysis of large complex clinical data streams currently being generated in the intensive care unit. Brain tissue oxygen protocols have yielded outcome benefits in traumatic brain injury (TBI), but the critical physiological thresholds for low brain oxygen have not been established for a dynamical patho-physiological system. High frequency, multi-modal clinical data sets from 29 patients with severe TBI who underwent multi-modality neuro-clinical care monitoring and treatment with a brain oxygen protocol were analyzed. The inter-relationship between acute physiological parameters was determined using symbolic regression (SR) as the computational framework. The mean patient age was 44.4±15 with a mean admission GCS of 6.6±3.9. Sixty-three percent sustained motor vehicle accidents and the most common pathology was intra-cerebral hemorrhage (50%). Hospital discharge mortality was 21%, poor outcome occurred in 24% of patients, and good outcome occurred in 56% of patients. Criticality for low brain oxygen was intracranial pressure (ICP) ≥22.8 mm Hg, for mortality at ICP≥37.1 mm Hg. The upper therapeutic threshold for cerebral perfusion pressure (CPP) was 75 mm Hg. Eubaric hyperoxia significantly impacted partial pressure of oxygen in brain tissue (PbtO2) at all ICP levels. Optimal brain temperature (Tbr) was 34-35°C, with an adverse effect when Tbr≥38°C. Survivors clustered at [Formula: see text] Hg vs. non-survivors [Formula: see text] 18 mm Hg. There were two mortality clusters for ICP: High ICP/low PbtO2 and low ICP/low PbtO2. Survivors maintained PbtO2 at all ranges of mean arterial pressure in contrast to non-survivors. The final SR equation for cerebral oxygenation is: [Formula: see text]. The SR-model of acute TBI advances new physiological thresholds or boundary conditions for acute TBI management: PbtO2≥25 mmHg; ICP≤22 mmHg; CPP≈60-75 mmHg; and Tbr≈34-37°C. SR is congruous with the emerging field of complexity science in the modeling of dynamical physiological systems, especially during pathophysiological states. The SR model of TBI is generalizable to known physical laws. This increase in entropy reduces uncertainty and improves predictive capacity. SR is an appropriate computational framework to enable future smart monitoring devices.

Although the pathologic processes that affect the spine remain largely unchanged, our techniques to correct them continue to evolve with the development of novel medical and surgical interventions. Although the primary purpose of new technologies is to improve patients' quality of life, the economic impact of such therapies must be considered.To review the available peer-reviewed literature on spine surgery that addresses the cost-effectiveness of various treatments and technologies.A narrative literature review.Articles published between January 1, 2000 and December 31, 2012 were selected from two Pubmed searches using keywords cost-effectiveness AND spine (216 articles) and cost analysis AND spine (358 articles). Relevant articles on cost analyses and cost-effectiveness were selected by the authors and reviewed.Cervical and lumbar surgeries (anterior cervical discectomy and fusion, standard open lumbar discectomy, and standard posterior lumbar laminectomy) are reasonably cost effective at 2 years after the procedure (<100,000 US dollars per quality-adjusted life years gained) and become more cost effective with time because of sustained clinical improvements with relatively low additional incurred costs. The usage of transfusion avoidance technology is not cost effective because of the low risk of complications associated with allogenic transfusions. Although intraoperative neuromonitoring and imaging modalities are both cost saving and cost-effective, their cost-effectiveness is largely dependent on the baseline rate of neurologic complications and implant misplacement, respectively. More rigorous studies are needed to evaluate the cost-effectiveness of recombinant bone morphogenetic protein.An ideal new technology should be able to achieve maximal improvement in patient health at a cost that society is willing to pay. The cost-effectiveness of technologies and treatments in spine care is dependent on their durability and the rate and severity of the baseline clinical problem that the treatment was designed to address.

Despite the varied sources of hydrocephalus, all shunt-treated conditions involve redirection of CSF to the body, commonly the peritoneum. Migration of the distal catheter tip out of the peritoneal space can occur, leading to the need for reoperation. Although uncommon, the authors have recently had 3 such cases in obese patients involving distal tubing retropulsion in otherwise uncomplicated surgeries. In addressing this issue, the authors performed anchoring of the distal catheter tubing through a small abdominal mesh, which is commonly used for hernia repair to increase catheter tube friction without compromising CSF flow. The results suggest this method may mitigate the chance of peritoneal catheter displacement in patients with higher than normal intraabdominal pressure.