Arnold Max Meirowsky: champion of the American mobile neurosurgical unit during the Korean War.

Dr. Arnold Max Meirowsky (1910-1984) was enormously influential to military neurosurgery during the Korean War, introducing to the American military the concept of the mobile neurosurgical unit. After implementation of the neurosurgical detachment, meningocerebral infections saw a decrease from 41% to less than 1%, with similar improvements in mortality and complication rates. Additionally, Meirowsky developed many techniques and improvements in neurosurgery, specifically in the field of neurosurgical trauma, which he dedicated himself to even after reentering civilian practice. Furthermore, his mentorship of Korean surgeons and the influence of his mobile neurosurgical unit were major influences cited to be pivotal to the founding of neurosurgery as a specialty in South Korea. As he is underrecognized for these accomplishments in the neurosurgical literature, the authors seek to review his wartime and career contributions. They also specifically present details of his standardization of the mobile neurosurgical unit and showcase several of his other advancements in the treatment of neurosurgical trauma.

Radiographic risk factors for intracranial hemorrhage in patients with left ventricular assist devices.

OBJECTIVE: Intracranial hemorrhage (ICH) in patients with left ventricular assist devices (LVAD) is a devastating complication. Demographic risk factors for ICH in LVAD patients are defined, however anatomic predispositions to ICH are unknown. We sought to interrogate intracranial radiographic risk factors for ICH in LVAD patients. METHODS: We reviewed 440 patients who received an LVAD from 2008-2021. We selected patients with CT scans of the head either before or after LVAD placement, but typically within 5 years. 288 patients (21 ICH, 267 Control) with imaging were included. A detailed chart review was performed on demographics, radiographic features, and management. RESULTS: The incidence of ICH in our total cohort was 8.6% (38/440). The presence of pump thrombosis (p=0.001), driveline infection (p=0.034), other hemorrhage (p=0.001), or previous placement of a cardio-defibrillator (p=.003) was associated with increased risk for ICH. An analysis of imaging revealed that the presence of a mass (p=0.006), vascular pathology (p=0.001), and microangiopathy (p=0.04) was significantly associated with ICH in LVAD patients. These radiographic features were validated with a multivariate logistic regression which confirmed presence of a mass (aOR 332.1, 95% CI: 14.7-7485.1, p<0.001), vascular pathology (aOR 69.7, 95% CI: 1.8-2658.8, p=0.022), and microangiopathy (aOR 6.5, 95% CI: 1.1-37.6, p=0.035) were independently associated with ICH. CONCLUSION: Radiographic evidence of microangiopathy, intracranial mass, and vascular pathology are independent risk factors for ICH which are readily identified by imaging. We advocate that CT imaging be used to further stratify patients at highest risk of ICH during treatment with an LVAD.

Morphometric analysis of lumbar pedicles in patients with spinal dysraphism.

BACKGROUND: In patients with open neural tube defects, the incidence of scoliosis and requirement for spinal fusions are increased. Historically, there has been no standardized measurement of vertebral morphometry in these patients. However, anecdotally, patients with open neural tube defects have a more medially oriented lumbar pedicle trajectory than the average population. METHODS: A single-institution retrospective review of patients with open neural tube defects was conducted. The demographic parameters and functional and anatomical levels of the defects were noted. CT and MRI scans of the lumbar spine were analyzed; the pedicles from L 1 to S 1 were measured for width (W), length (L) and midline angle (α). The measurements were compared bilaterally, at each level, and with data from previously published reports. RESULTS: 16 scans of pediatric patients (mean = 3.0 ・} 4.3; age range = 7 days to 14.4 years; 7 males, 9 females) with a diagnosis of either myelomeningocele or lipomyelomeningocele were assessed. Most defects occurred in the lumbar region, with L 2 and L 5 accounting for 37.5% each. All angles demonstrated a quadratic increase from L 1 to S 1 (means: L 1 = 28.3 ・} 5.24° ; L 2 = 29.1 ・} 6.2°; L 3 = 33.2 ・} 6.0°; L 4 = 36.8 ・} 5.6°; L 5 = 43.8 ・} 5.9°; S 1 = 52.0 ・} 3.6°) and were more medially angulated than those reported previously; no significant difference existed between right and left measurements (W = 0.65 ≤ p ≤ 0.94; L = 0.91 ≤ p ≤ 1; α = 0.24 ≤p ≤0.86). CONCLUSIONS: Patients with open neural tube defects had more medially angled pedicle trajectories in the lumbar spine when compared to previously reported values.

Lateral retroperitoneal transpsoas approach to the lumbar spine for the treatment of spondylodiscitis.

Spondylodiscitis is an infection of the intervertebral disc and adjacent vertebrae. With the advent of minimally invasive spinal surgery, less invasive approaches have been considered for the treatment of discitis. To date, however, there have been no reported cases of a minimally invasive lateral retroperitoneal transpsoas approach for the treatment of spondylodiscitis. The authors report a case of medically refractory discitis in a patient with multiple comorbidities who underwent a successful limited debridement via a lateral transpsoas corridor. This case describes a minimally invasive approach used to treat a patient with lumbar discitis/osteomyelitis who was otherwise a suboptimal surgical candidate.

Inadequate Spinal Anesthesia in Lumbar Spine Surgery Is Related to Volume of the Thecal Sac.

BACKGROUND: Spinal anesthesia (SA) is used in lumbar surgery, but initial adequate analgesia fails in some patients. In these cases, spinal redosing or conversion to general endotracheal anesthesia is required, both of which are detrimental to the patient experience and surgical workflow. METHODS: We reviewed cases of lumbar surgery performed under SA from 2017-2021. We identified 12 cases of inadequate first dose and then selected 36 random patients as controls. We used a measurement tool to approximate the volume of the dural sac for each patient using T2-weighted sagittal magnetic resonance imaging sequences. RESULTS: Patients who had an inadequate first dose of anesthesia had a significantly larger dural sac volume, 22.8 ± 7.9 cm3 in the inadequate dose group and 17.4 ± 4.7 cm3 in controls (P = 0.043). The inadequate dose group was significantly younger, 54.2 ± 8.8 years in failed first dose and 66.4 ± 11.9 years in controls (P = 0.001). The groups did not differ by surgical procedure (P = 0.238), level (P = 0.353), American Society of Anesthesia score (P = 0.546), or comorbidities. CONCLUSIONS: We found that age, larger height, and dural sac volume are risk factors for an inadequate first dose of SA. The availability of spinal magnetic resonance imaging in patients undergoing spine surgery allows the preoperative measurement of their thecal sac size. In the future, these data may be used to personalize spinal anesthesia dosing on the basis of individual anatomic variables and potentially reduce the incidence of failed spinal anesthesia in spine surgery.

Spinal Anesthesia Reduces Perioperative Polypharmacy and Opioid Burden in Patients Over 65 Who Undergo Transforaminal Lumbar Interbody Fusion.

BACKGROUND: Polypharmacy and opioid administration are thought to increase the risk of postoperative cognitive dysfunction and delirium in elderly patients. Spinal anesthesia (SA) holds potential to reduce perioperative polypharmacy in spine surgery. As more geriatric patients undergo spine surgery, understanding how SA can reduce polypharmacy and opioid administration is warranted. We aim to compare the perioperative polypharmacy and dose of administered opioids in patients ≥65 years who undergo transforaminal lumbar interbody fusion (TLIF) under SA versus general anesthesia (GA). METHODS: A retrospective analysis of 200 patients receiving a single-surgeon TLIF procedure at a single academic center (2014-2021) was performed. Patients underwent the procedure with SA (n = 120) or GA (n = 80). Demographic, procedural, and medication data were extracted from the medical record. Opioid consumption was quantified as morphine milligram equivalents (MME). Statistical analyses included χ2 or Student's t-test. RESULTS: Patients receiving SA were administered 7.45 medications on average versus 12.7 for GA patients (P < 0.001). Average perioperative opioid consumption was 5.17 MME and 20.2 MME in SA and GA patients, respectively (P < 0.001). The number of patients receiving antiemetics and opioids remained comparable postoperatively, with a mean of 32.2 MME in the GA group versus 27.5 MME in the SA group (P = 0.14). Antiemetics were administered less often as a prophylactic in the SA group (32%) versus 86% in the GA group (P < 0.001). CONCLUSIONS: SA reduces perioperative polypharmacy in patients ≥65 years undergoing TLIF procedures. Further research is necessary to determine if this reduction correlates to a decrease the incidence of postoperative cognitive dysfunction and delirium.

Erector Spinae Plane Block Placement Utilizing Fluoroscopic Guidance Improves Efficiency in Lumbar Surgery.

OBJECTIVE: The erector spinae plane block (ESPB) is a novel regional analgesic technique which improves postoperative outcomes in lumbar surgery patients including length of hospitalization, days to ambulation, and postoperative opioid use. Traditionally, the block is administered by anesthesiologists trained in the ultrasound guidance technique. The use of fluoroscopic guidance may improve the efficiency and accessibility of the ESPB for spine surgeons. We aim to measure the time to administer an ESPB using fluoroscopic guidance and localize the anesthetic using intraoperative three-dimensional (3D) imaging. METHODS: Two neurosurgeons administered an ESPB to patients undergoing lumbar surgery. Time from insertion of the spinal needle to localize the erector spinae plane using C-arm guidance to time of complete injection and removal of the needle from the skin was recorded. One patient underwent O-arm imaging following injection of an Isovue-Exparel solution at the L3 level to visualize spread of the anesthetic. RESULTS: A total of 21 patients were enrolled in this study. The average duration to perform an ESPB under fluoroscopic guidance was 1.2 minutes. The Isovue-Exparel solution was injected at the L3 level and was well distributed along the ESP on intraoperative O-arm imaging. The anesthetic dissected the erector spinae muscle from the transverse process at L2, L3, and L4. CONCLUSIONS: Fluoroscopic guidance allows efficient and appropriate delivery of the anesthetic to the erector spinae plane. Performing an ESPB with fluoroscopic guidance improves efficiency and accessibility of the analgesic technique for spine surgeons, reducing dependence on anesthesiology personnel trained in administering the block.

The Relationship of Spinal Anesthesia Dosing Based on Thecal Sac Area to Anesthetic Failure in Lumbar Surgery.

BACKGROUND AND OBJECTIVES: Greater thecal sac volumes are associated with an increased risk of spinal anesthesia (SA) failure. The thecal sac cross-sectional area accurately predicts thecal sac volume. The thecal sac area may be used to adjust the dose and prevent anesthetic failure. We aim to assess the rate of SA failure in a prospective cohort of lumbar surgery patients who receive an individualized dose of bupivacaine based on preoperative measurement of their thecal sac area. METHODS: A total of 80 patients prospectively received lumbar spine surgery under SA at a single academic center (2022-2023). Before surgery, the cross-sectional area of the thecal sac was measured at the planned level of SA injection using T2-weighted MRI. Patients with an area <175 mm2, equal to or between 175 and 225 mm2, and >225 mm2 received an SA injection of 15, 20, or 25 mg of 0.5% isobaric bupivacaine, respectively. Instances of anesthetic failure and adverse outcomes were noted. Incidence of SA failure was compared with a retrospectively obtained control cohort of 250 patients (2019-2022) who received the standard 15 mg of bupivacaine. RESULTS: No patients in the individualized dose cohort experienced failure of SA compared with 14 patients (5.6%) who experienced failure in the control cohort (P = .0259). The average thecal sac area was 187.49 mm2, and a total 28 patients received 15 mg of bupivacaine, 42 patients received 20 mg of bupivacaine, and 10 patients received 25 mg of bupivacaine. None of the patients experienced any adverse outcomes associated with SA. Patients in the individualized dose cohort and control cohort were comparable and had a similar distribution of lumbar procedures and comorbidities. CONCLUSION: Adjusting the dose of SA according to thecal sac area significantly reduces the rate of SA failure in patients undergoing lumbar spine surgery.

A retrospective comparison of CT and MRI in detecting pediatric cervical spine injury.

PURPOSE: Although clinical criteria have been applied in the assessment of pediatric cervical spine trauma, no consensus has been established when imaging is required. With the increasing prevalence of computed tomography (CT) use in pediatric trauma and the concern for radiation in children, we sought to evaluate magnetic resonance imaging (MRI) and CT in detecting pediatric cervical spine injuries. METHODS: We retrospectively queried a pediatric trauma database and identified pediatric patients who underwent both CT and MRI studies of the cervical spine and derived the statistical measures of each imaging modality to detect osseous and ligamentous/soft tissue injury. RESULTS: Eighty-four patients were identified with a mean age of 9.0 ± 5.8 years (56% male). Sixteen patients were identified with injury, 12 with soft tissue abnormalities on MRI (nine edema and six ligamentous), and 6 with osseous abnormalities on CTs (six osseous fractures and one discogenic injury). Of the six patients who presented with CT-identified osseous injuries, MRI detected all six fractures as well as an additional compression fracture. CONCLUSION: Using CT as the standard for osseous injury, MRI had a sensitivity of 100%, specificity of 97%, negative predictive value (NPV) of 75%, and positive predictive value (PPV) of 100%. Using MRI as the standard for soft tissue injury, CT had a sensitivity of 23%, specificity of 100%, NPV of 88%, and PPV of 100%. Further studies are required to investigate the use of MRI to detect osseous injuries.

Nerve root anomalies: implications for transforaminal lumbar interbody fusion surgery and a review of the Neidre and Macnab classification system.

Lumbar nerve root anomalies are uncommon phenomena that must be recognized to avoid neural injury during surgery. The authors describe 2 cases of nerve root anomalies encountered during mini-open transforaminal lumbar interbody fusion (TLIF) surgery. One anomaly was a confluent variant not previously classified; the authors suggest that this variant be reflected in an amendment to the Neidre and Macnab classification system. They also propose strategies for identifying these anomalies and avoiding injury to anomalous nerve roots during TLIF surgery. Case 1 involved a 68-year-old woman with a 2-year history of neurogenic claudication. An MR image demonstrated L4-5 stenosis and spondylolisthesis and an L-4 nerve root that appeared unusually low in the neural foramen. During a mini-open TLIF procedure, a nerve root anomaly was seen. Six months after surgery this patient was free of neurogenic claudication. Case 2 involved a 60-year-old woman with a 1-year history of left L-4 radicular pain. Both MR and CT images demonstrated severe left L-4 foraminal stenosis and focal scoliosis. Before surgery, a nerve root anomaly was not detected, but during a unilateral mini-open TLIF procedure, a confluent nerve root was identified. Two years after surgery, this patient was free of radicular pain.

Surgeons' perspectives on optimal patient positioning during simultaneous cranial procedures and exploratory laparotomy.

OBJECTIVES: Patients presenting with traumatic intracranial and intraabdominal injuries often require emergent care. Triage of injuries is based on severity of the individual injuries, but treatment occasionally must proceed simultaneously. Determining an optimal patient position at the time of surgery often produces unnecessary delays and this delay may negatively affect patient outcome. This study aimed to determine an operative patient position that simultaneously optimizes access to neurosurgical and general surgical teams without compromising sterility or severely affecting surgeon and anesthesia comfort. METHODS: Photographs of traditional exploratory laparotomy patient positioning (position A), traditional supine craniotomy patient positioning (position B), and a hybrid patient position (position C) were presented to 29 general surgeons and 12 neurosurgeons at a single institution. Surgeons were asked to rate the positions on acceptability and to rank the three positions according to preference when simultaneous exploratory laparotomy and craniotomy were necessary. RESULTS: Position C was rated as an acceptable option by 82.8% of general surgeons and 100% of neurosurgeons. In addition, 51.9% of general surgeons and 81.8% of neurosurgeons preferred position C to their respective specialty's traditional patient positioning in situations that required simultaneous exploratory laparotomy and craniotomy. CONCLUSIONS: We present a novel hybrid operative patient position for use during simultaneous exploratory laparotomy and craniotomy. In doing so, we emphasize the importance of constructive dialogue among trauma surgeons and neurosurgeons in optimizing the care of acutely ill trauma patients with multisystem injuries.

Intraoperative Triggered Electromyography for Pedicle Screw Placement Under Spinal Anesthesia: A Preliminary Report.

BACKGROUND: Triggered electromyography (tEMG) is an intraoperative neuromonitoring technique used to assess pedicle screw placement during instrumented fusion procedures. Although spinal anesthesia is a safe alternative to general anesthesia in patients undergoing lumbar fusion, its use may potentially block conduction of triggered action potentials or may require higher threshold currents to elicit myotomal responses when using tEMG. Given the broad utilization of tEMG for confirmation of pedicle screw placement, adoption of spinal anesthesia may be hindered by limited studies of its use alongside tEMG. OBJECTIVE: To investigate whether spinal anesthesia affects the efficacy of tEMG, we compare the baseline spinal nerve thresholds during lumbar fusion procedures under general vs spinal anesthesia. METHODS: Twenty-three consecutive patients (12 general and 11 spinal) undergoing single-level transforaminal lumbar interbody fusion were included in the study. Baseline nerve threshold was determined through direct stimulation of the spinal nerve using tEMG. RESULTS: Baseline spinal nerve threshold did not differ between the general and spinal anesthesia cohorts (3.25 ± 1.14 vs 3.64 ± 2.16 mA, respectively; P = .949). General and spinal anesthesia cohorts did not differ by age, body mass index, American Society of Anesthesiologists score status, or surgical indication. CONCLUSION: We report that tEMG for pedicle screw placement can be safely and effectively used in procedures under spinal anesthesia. The baseline nerve threshold required to illicit a myotomal response did not differ between patients under general or spinal anesthesia. This preliminary finding suggests that spinal anesthetic blockade does not contraindicate the use of tEMG for neuromonitoring during pedicle screw placement.

Periprocedural Polypharmacy in Lumbar Fusions Performed Under Spinal Anesthesia Compared With General Anesthesia.

BACKGROUND: Spinal anesthesia (SA) is a safe and effective alternative to general endotracheal anesthesia (GEA) for lumbar surgery. Foremost among the reasons to avoid GEA is the desire to minimize postoperative cognitive dysfunction (POCD). Although POCD is a complex and multifactorial entity, the risk of its development has been associated with anesthetic modality and perioperative polypharmacy, among others. OBJECTIVE: To determine whether SA reduced polypharmacy compared with GEA in patients undergoing transforaminal lumbar interbody fusion (TLIF). METHODS: Demographic and procedural data of 424 consecutive TLIF patients were extracted retrospectively. Patients undergoing single-level TLIF through GEA (n = 186) or SA (n = 238) were enrolled into our database. Perioperative medications, excluding antibiotic prophylaxis and local anesthetics, were classified into various categories. RESULTS: Patients in the SA cohort received a mean of 4.5 medications vs a mean of 10.5 medications in the GEA cohort ( P < .0001). This reduction in perioperative medications remained significant after a multivariate analysis to control for confounders ( P < .001 for all variables). The use of vasopressors was significantly reduced in the SA cohort ( P < .001), which coincided with a significant reduction in hypotensive episodes ( P < .001). Patients undergoing TLIF through GEA had 3.6 times greater odds of experiencing a hypotensive episode intraoperatively (odds ratio = 3.62, 95% CI [2.38-5.49]). CONCLUSION: Spinal anesthesia is associated with a significant decrease in perioperative medications and may confer superior intraoperative hemodynamic stability, which lowers pressor requirements. The decrease of perioperative medications may be an important contribution in reducing the incidence of POCD in patients undergoing TLIFs, although this requires further study.

Spinal anesthesia in elective lumbar spinal surgery.

Spinal anesthesia (SA) is gaining recognition as a safe and efficacious regional alternative to general anesthesia for elective lumbar surgery. However, unfamiliarity with management issues related to its use has limited the adoption of awake spine surgery, despite its benefits. Few centers in the United States routinely offer SA for elective lumbar surgery, and a comprehensive workflow to standardize SA for lumbar surgery is lacking. In this article, we examine recent literature on the use of SA in lumbar surgery, review the experience of our institution with SA in lumbar surgery, and provide a cohesive outline to streamline the implementation of SA from the perspective of the anesthesiologist. We review the critical features of SA in contemporary lumbar surgery, including selection of patients, methods of SA, intraoperative sedation, and management of several important technical considerations. We aimed to flatten the learning curve to improve the availability and accessibility of the technique for eligible patients.

Clinical Outcomes of Liposomal Bupivacaine Erector Spinae Block in Minimally Invasive Transforaminal Lumbar Interbody Fusion Surgery.

BACKGROUND: Postoperative pain is a barrier to early mobility and discharge after lumbar surgery. Liposomal bupivacaine (LB) has been shown to decrease postoperative pain and narcotic consumption after transforaminal lumbar interbody fusions (TLIFs) when injected into the marginal suprafascial/subfascial plane-liposomal bupivacaine (MSSP-LB). Erector spinae plane (ESP) infiltration is a relatively new analgesic technique that may offer additional benefits when performed in addition to MSSP-LB. OBJECTIVE: To evaluate postoperative outcomes of combining ESP-LB with MSSP-LB compared with MSSP-LB alone after single-level TLIF. METHODS: A retrospective analysis was performed for patients undergoing single-level TLIFs under spinal anesthesia, 25 receiving combined ESP-LB and MSSP-LB and 25 receiving MSSP-LB alone. The primary outcome was length of hospitalization. Secondary outcomes included postoperative pain score, time to ambulation, and narcotics usage. RESULTS: Baseline demographics and length of surgery were similar between groups. Hospitalization was significantly decreased in the ESP-LB + MSSP-LB cohort (2.56 days vs 3.36 days, P = .007), as were days to ambulation (0.96 days vs 1.29 days, P = .026). Postoperative pain area under the curve was significantly decreased for ESP-LB + MSSP-LB at 12 to 24 hours (39.37 ± 21.02 vs 53.38 ± 22.11, P = .03) and total (44.46 ± 19.89 vs 50.51 ± 22.15, P = .025). Postoperative narcotic use was significantly less in the ESP-LB + MSSP-LB group at 12 to 24 hours (13.18 ± 4.65 vs 14.78 ± 4.44, P = .03) and for total hospitalization (137.3 ± 96.3 vs 194.7 ± 110.2, P = .04). CONCLUSION: Combining ESP-LB with MSSP-LB is superior to MSSP-LB alone for single-level TLIFs in decreasing length of hospital stay, time to ambulation, postoperative pain, and narcotic use.

Assessing the Safety and Efficacy of Spinal Anesthesia in Patients with Significant Comorbidities.

BACKGROUND: Spinal anesthesia is an effective modality for lumbar surgery. Patient eligibility with respect to medical comorbidities remains a topic of debate. Obesity (body mass index ≥30 kg/m2), anxiety, obstructive sleep apnea, reoperation at the same level, and multilevel operations have variously been reported as relative contraindications. We hypothesize that patients undergoing common lumbar surgeries with these comorbidities do not experience greater rates of complications compared with controls. METHODS: We analyzed a prospectively collected database of patients undergoing thoracolumbar surgery under spinal anesthesia and identified 422 cases. Surgeries were less than 3 hours (the duration of action of intrathecal bupivacaine) and include microdiscectomies, laminectomies, and both single-level and multilevel fusions. Procedures were performed by a single surgeon at a single academic center. In overlapping groups, 149 patients had a body mass index ≥30 kg/m2, 95 had diagnosed anxiety, 79 underwent multilevel surgery, 98 had obstructive sleep apnea, and 65 had a previous operation at the same level. The control group included 132 patients who did not have these risk factors. Differences in important perioperative outcomes were assessed. RESULTS: There were no statistically significant differences in intraoperative and postoperative complications except 2 cases of pneumonia in the anxiety group and 1 case in the reoperative group. There were also no significant differences for patients with multiple risk factors. Rates of spinal fusion were similar among groups, although mean length of stay and operative time were different. CONCLUSIONS: Spinal anesthesia is a safe option for patients with significant comorbidities and can be considered for most patients undergoing routine lumbar surgeries.

A Second Prone Dose Algorithm for Patients Undergoing Spinal Anesthesia During Thoracolumbar Surgeries.

BACKGROUND: Spinal anesthesia is safe and effective in lumbar surgeries, with numerous advantages over general anesthesia (GA). Nevertheless, 1 major concern preventing the widespread adoption of this anesthetic modality in spine surgeries is the potential for intraprocedural anesthetic failure, resulting in the need to convert to GA intraoperatively. OBJECTIVE: To present a novel additional prone dose algorithm for when a first spinal dose fails to achieve the necessary effect. METHODS: A total of 422 consecutive patients undergoing simple and complex thoracolumbar surgeries under spinal anesthesia were prospectively enrolled into our database. Data were retrospectively collected through extraction of electronic health records. RESULTS: Sixteen of 422 required a second prone dose, of whom 1 refused and was converted to GA preoperatively. After 15 were given a prone dose, only 2 required preoperative conversion to GA. There were no instances of intraoperative conversion to GA. The success rate for spinal anesthesia without the need for conversion rose from 96.4% to 99.5%. In patients who required a second prone dose, there were no instances of spinal headache, deep vein thrombosis, pneumonia, urinary tract infection, urinary retention, readmission within 30 days, acute pain service consult, return to operating room, durotomy, or cerebrospinal fluid on puncture. CONCLUSION: Use of an additional prone dose algorithm was able to achieve a 99.5% success rate, and those who received this second dose did not experience any complications or negative operative disadvantages. Further research is needed to investigate which patients are at increased risk of inadequate analgesia with spinal anesthesia.

The Emerging Significance of Amyloid Deposits in the Ligamentum Flavum of Spinal Stenosis Patients: A Review.

Spinal stenosis is one of the most common neurosurgical diseases and a leading cause of pain and disability. Wild-type transthyretin amyloid (ATTRwt) has been found in the ligamentum flavum (LF) of a significant subset of patients with spinal stenosis who undergo decompression surgery. Histologic and biochemical analyses of LF specimens from spinal stenosis patients, normally discarded as waste, have the potential to help elucidate the underlying pathophysiology of spinal stenosis and possibly allow for medical treatment of stenosis and screening for other systemic diseases. In the present review, we discuss the utility of analyzing LF specimens after spinal stenosis surgery for ATTRwt deposits. Screening for ATTRwt amyloidosis cardiomyopathy through LF specimens has led to the early diagnosis and treatment of cardiac amyloidosis in several patients, with more expected to benefit from this process. Emerging evidence in the literature also point to ATTRwt as a contributor to a previously unrecognized subtype of spinal stenosis in patients who might, in the future, benefit from medical therapy. In the present report, we review the current literature regarding the early detection of ATTRwt cardiomyopathy via LF screening and the possible contribution of ATTRwt deposits in the LF to spinal stenosis development.

The New England Neurosurgical Society: growth and evolution over 70 years.

The New England Neurosurgical Society (NENS) was founded in 1951 under the leadership of its first President (Dr. William Beecher Scoville) and Secretary-Treasurer (Dr. Henry Thomas Ballantine). The purpose of creating the NENS was to unite local neurosurgeons in the New England area; it was one of the first regional neurosurgical societies in America. Although regional neurosurgical societies are important supplements to national organizations, they have often been overshadowed in the available literature. Now in its 70th year, the NENS continues to serve as a platform to represent the needs of New England neurosurgeons, foster connections and networks with colleagues, and provide research and educational opportunities for trainees. Additionally, regional societies enable discussion of issues uniquely relevant to the region, improve referral patterns, and allow for easier attendance with geographic proximity. In this paper, the authors describe the history of the NENS and provide a roadmap for its future. The first section portrays the founders who led the first meetings and establishment of the NENS. The second section describes the early years of the NENS and profiles key leaders. The third section discusses subsequent neurosurgeons who steered the NENS and partnerships with other societies. In the fourth section, the modern era of the NENS and its current activities are highlighted.

The use of intra-operative navigation during complex lumbar spine surgery under spinal anesthesia.

BACKGROUND: Spinal anesthesia is a safe and effective alternative to general anesthesia in both simple and complex lumbar surgery with numerous reported advantages leading to increased recent utilization. One potential barrier to the use of spinal anesthesia in lumbar surgery is the popularity of intraoperative computed tomography (CT) imaging. Intraoperative CT necessitates motionless patients and adds time to procedures, issues that may make surgeons hesitant to use concomitant spinal anesthesia. To date, the use of both techniques simultaneously has not been well described. OBJECTIVE: We propose that single-level lumbar fusions utilizing intraoperative CT scan acquisition and navigated instrumentation are feasible under single-dose spinal anesthesia without detrimental effect on image quality and navigation accuracy or need for spinal anesthetic re-dosing due to the additional time necessary. METHODS: We describe operative characteristics and intra-operative timing for our first five cases of transforaminal lumbar interbody fusion (TLIF) completed with intraoperative CT scan acquisition and navigated instrumentation performed under spinal anesthesia. RESULTS: The five patients ranged in age from 59 to 79 years, with an average body mass index of 27.0 kg/m2. The average total operative time for each surgery 109.2 min, including approximately 6.3 min required for CT scan acquisition. There were no complications and post-operative imaging demonstrated no malpositioned pedicle screws. CONCLUSION: Single-level TLIF procedures utilizing intraoperative CT acquisition and navigated instrumentation can be feasibly completed under single-dose spinal anesthesia without need for intraoperative apneic periods and without deleterious effect on instrumentation accuracy.