Adenosine modifications impede SARS-CoV-2 RNA-dependent RNA transcription.

SARS-CoV-2, the causative virus of the COVID-19 pandemic, follows SARS and MERS as recent zoonotic coronaviruses causing severe respiratory illness and death in humans. The recurrent impact of zoonotic coronaviruses demands a better understanding of their fundamental molecular biochemistry. Nucleoside modifications, which modulate many steps of the RNA lifecycle, have been found in SARS-CoV-2 RNA, although whether they confer a pro- or anti-viral effect is unknown. Regardless, the viral RNA-dependent RNA polymerase will encounter these modifications as it transcribes through the viral genomic RNA. We investigated the functional consequences of nucleoside modification on the pre-steady state kinetics of SARS-CoV-2 RNA-dependent RNA transcription using an in vitro reconstituted transcription system with modified RNA templates. Our findings show that N6-methyladenosine and 2'O-methyladenosine modifications slow the rate of viral transcription at magnitudes specific to each modification, which has the potential to impact SARS-CoV-2 genome maintenance.

Incidence of radiographic and clinically significant pneumothorax or hemothorax after thoracic discectomy via mini-open lateral retropleural approach without prophylactic chest tube placement.

OBJECTIVE: The mini-open lateral retropleural (MO-LRP) approach is an effective option for surgically treating thoracic disc herniations, but the approach raises concerns for pneumothorax (PTX). However, chest tube placement causes insertion site tenderness, necessitates consultation services, increases radiation exposure (requires multiple radiographs), delays the progression of care, and increases narcotic requirements. This study examined the incidence of radiographic and clinically significant PTX and hemothorax (HTX) after the MO-LRP approach, without the placement of a prophylactic chest tube, for thoracic disc herniation. METHODS: This study was a single-institution retrospective evaluation of consecutive cases from 2017 to 2022. Electronic medical records were reviewed, including postoperative chest radiographs, radiology and operative reports, and postoperative notes. The presence of PTX or HTX was determined on chest radiographs obtained in all patients immediately after surgery, with interval radiographs if either was present. The size was categorized as large (≥ 3 cm) or small (< 3 cm) based on guidelines of the American College of Chest Physicians. PTX or HTX was considered clinically significant if it required intervention. RESULTS: Thirty patients underwent thoracic discectomy via the MO-LRP approach. All patients were included. Twenty patients were men (67%), and 10 (33%) were women. The patients ranged in age from 25 to 74 years. The most commonly treated level was T11-12 (n = 11, 37%). Intraoperative violation of parietal pleura occurred in 5 patients (17%). No patient had prophylactic chest tube placement. Fifteen patients (50%) had PTX on postoperative chest radiographs; 2 patients had large PTXs, and 13 had small PTXs. Both patients with large PTXs had expansion on repeat radiographs and were treated with chest tube insertion. Of the 13 patients with a small PTX, 1 required 100% oxygen using a nonrebreather mask; the remainder were asymptomatic. One patient, who had no abnormal findings on the immediate postoperative chest radiograph, developed an incidental HTX on postoperative day 6 and was treated with chest tube insertion. Thus, 3 patients (10%) required a chest tube: 2 for expanding PTX and 1 for delayed HTX. CONCLUSIONS: Most patients who undergo thoracic discectomy via the MO-LRP approach do not develop clinically significant PTX or HTX. PTX and HTX in this patient population should be treated with a chest tube only when there are postoperative clinical and radiographic indications.

Academic career progression in AANS/CNS Spine Section award recipients.

OBJECTIVE: The American Association of Neurological Surgeons (AANS)/Congress of Neurological Surgeons (CNS) Joint Spine Section awards highlight outstanding abstracts submitted to the AANS/CNS Section on Disorders of the Spine and Peripheral Nerves by trainees interested in spine surgery, although the academic trajectory of awardees has not been studied. The aim of this study was to assess the academic career progression of prior recipients of the Journalistic and Academic Neurosurgical Excellence (JANE), Mayfield, and Kuntz research awards. METHODS: Prior JANE, Mayfield, and Kuntz award recipients were identified using awardee records accrued between 1984 and February 2022. Awardee sex, country of residence, specialty, subspecialty focus, and current academic appointment status (if applicable) were searched online. Awardee h-indices and number of peer-reviewed publications were assessed via Google Scholar profiles (or Scopus if unavailable) and PubMed, respectively. Receipt of federal research funding as principal investigator (PI) was determined using the websites of the National Institutes of Health, the National Science Foundation, and the Department of Defense Congressionally Directed Medical Research Programs. The abstract-to-publication rate was assessed. RESULTS: A total of 7 JANE awards, 57 Mayfield awards, and 149 Kuntz awards were identified. Of the JANE awardees, all recipients were male. Of the 4 unique JANE awardees who completed training, 2 (50.0%) held academic appointments at the time of the study. All of the JANE abstracts were published in peer-reviewed journals. The mean h-index of all JANE awardees was 28 and the mean number of publications was 126. None of the awardees have received federal research funding. Of the Mayfield awards, 98.2% were awarded to males. Of the 43 unique Mayfield awardees who completed training, 20 (46.5%) held faculty appointments at academic medical centers. All of the Mayfield abstracts since 2011 were published in peer-reviewed journals. The mean h-index of all Mayfield awardees was 26 and the mean number of publications was 82. Five Mayfield awardees received National Institutes of Health funding as PI, and 7 awardees received Department of Defense funding as PI. Of the Kuntz awards, 95.3% were awarded to males. Most awards were given to current residents and fellows (46.3%). Of the 55 unique Kuntz awardees who completed training, 31 (56.4%) held faculty appointments at academic medical centers. The abstract-to-publication rate of the total Kuntz abstracts was 70.5%. The mean h-index of all Kuntz awardees was 15 and the mean number of publications was 58. Five Kuntz awardees (3.4%) received federal research funding as PI. CONCLUSIONS: Many recipients of the JANE, Mayfield, and Kuntz Joint Spine Section awards have successfully translated award abstracts into peer-reviewed publications. Furthermore, approximately one-third of the awardees are active in academic neurosurgery, with some having secured federal research funding.

Pentobarbital coma for management of intracranial hypertension following traumatic brain injury: Lack of early response to treatment portends poor outcomes.

INTRODUCTION: Traumatic brain injury (TBI) results in the death of over 50,000 and the permanent disability of 80,000 individuals annually in the United States. Much of the permanent disability is the result of secondary brain injury from intracranial hypertension (ICH). Pentobarbital coma is often instituted following the failure of osmotic interventions and sedation to control intracranial pressure (ICP). The goal of this study was to evaluate the efficacy of pentobarbital coma with respect to ICP management and long-term functional outcome. METHODS: Traumatic brain injury patients who underwent pentobarbital coma at a level 1 trauma center between 2014 and 2021 were identified. Patient demographics, injury characteristics, Glasgow Coma Scale (GCS) scores, intracranial pressures (ICPs), and outcomes were obtained from the trauma registry as well as inpatient and outpatient medical records. The proportion of ICPs below 20 for each hospitalized patient-day was calculated. The primary outcome measured was GCS score at the last follow-up visit. RESULTS: 25 patients were identified, and the majority were male (n â€‹= â€‹23, 92%) with an average age of 30.0 years â€‹± â€‹12.9 and median injury severity score of 30 (21.5-33.5). ICPs were monitored for all patients with a median of 464 (326-1034) measurements. The average hospital stay was 16.9 days â€‹± â€‹11.5 and intensive care stay was 16.9 â€‹± â€‹10.8 days. 9 (36.0%) patients survived to hospital discharge. Mean follow-up time in months was 36.9 â€‹± â€‹28.0 (min-max 3-80). 7 of the 9 surviving patients presented as GCS 15 on follow-up and the remaining were both GCS 9. Patients presenting at last follow-up with GCS 15 had a significantly higher proportion of controlled ICPs throughout their hospitalization compared to patients who expired or with follow-up GCS <15 (GCS 15: 88% â€‹± â€‹10% vs. GCS <15 or dead: 68% â€‹± â€‹22%, P â€‹= â€‹0.006). A comparison of the daily proportion of controlled ICPs by group revealed negligible differences prior to pentobarbital initiation. Groups diverged nearly immediately upon pentobarbital coma initiation with a higher proportion of controlled ICPs for patients with follow-up GCS of 15. CONCLUSION: Patients that do not have an immediate response to pentobarbital coma therapy for ICH universally had poor outcomes. Alternative therapy or earlier palliation should be considered for such patients. In contrast, patients whose ICPs responded quickly to pentobarbital had excellent long-term outcomes.

Complications associated with single-position prone lateral lumbar interbody fusion: a systematic review and pooled analysis.

OBJECTIVE: Lateral lumbar interbody fusion (LLIF) is a workhorse surgical approach for lumbar arthrodesis. There is growing interest in techniques for performing single-position surgery in which LLIF and pedicle screw fixation are performed with the patient in the prone position. Most studies of prone LLIF are of poor quality and without long-term follow-up; therefore, the complication profile related to this novel approach is not well known. The objective of this study was to perform a systematic review and pooled analysis to understand the safety profile of prone LLIF. METHODS: A systematic review of the literature and a pooled analysis were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. All studies reporting prone LLIF were assessed for inclusion. Studies not reporting complication rates were excluded. RESULTS: Ten studies meeting the inclusion criteria were analyzed. Overall, 286 patients were treated with prone LLIF across these studies, and a mean (SD) of 1.3 (0.2) levels per patient were treated. The 18 intraoperative complications reported included cage subsidence (3.8% [3/78]), anterior longitudinal ligament rupture (2.3% [5/215]), cage repositioning (2.1% [2/95]), segmental artery injury (2.0% [5/244]), aborted prone interbody placement (0.8% [2/244]), and durotomy (0.6% [1/156]). No major vascular or peritoneal injuries were reported. Sixty-eight postoperative complications occurred, including hip flexor weakness (17.8% [21/118]), thigh and groin sensory symptoms (13.3% [31/233]), revision surgery (3.8% [3/78]), wound infection (1.9% [3/156]), psoas hematoma (1.3% [2/156]), and motor neural injury (1.2% [2/166]). CONCLUSIONS: Single-position LLIF in the prone position appears to be a safe surgical approach with a low complication profile. Longer-term follow-up and prospective studies are needed to better characterize the long-term complication rates related to this approach.

Safe dissection and complication avoidance for L1-2 interbody placement via a lateral access approach.

The lateral access approach for L1-2 interbody placement or other levels at or near the thoracolumbar junction may be difficult without proper knowledge and visualization of anatomy. Specifically, understanding where the fibers of the diaphragm travel and avoiding injury to the diaphragm are paramount. The video can be found here: https://stream.cadmore.media/r10.3171/2022.3.FOCVID2221.

Surgical Technique, Indications, and Outcomes of BIOM-Assisted Transvitreal Biopsy for Uveal Melanoma.

PURPOSE: Controversy exists regarding the best method for biopsy of uveal melanoma. We describe our transvitreal technique and evaluate the safety of this technique as well as the efficacy for obtaining sample for prognostic genetic profiling. METHODS: Description of surgical technique and retrospective case series. Medical records for uveal melanoma patients who underwent transvitreal biopsy using our described technique were analyzed for tumor size, location, primary treatment, method of biopsy, and any complications thereof. Characteristics of tumors that underwent transvitreal biopsy were noted including tumor size, location, or presence of subretinal fluid, to see whether these affected surgeon preference for biopsy modality. A cohort of contemporaneous uveal melanoma patients who underwent biopsy through a transscleral technique served as a comparator group for these patient, tumor, and complication factors. RESULTS: A total of 27 patients aged 27.2 to 88.6 years (mean 64.8) underwent transvitreal biopsy using our described technique between 2013 and 2016. There were 15 small, 10 medium, and 2 large tumors at diagnosis with the majority (n = 17) posterior to the equator. Intraoperative complications included a clot or small trickle of blood at the biopsy site in 20 (74.1%) of patients, small localized subretinal hemorrhage in 8 (29.6%), small vitreous hemorrhage in 4 (14.8%), and small transient choroidal detachments in 1 patient (3.6%). When subretinal hemorrhage occurred, it was almost always into a pre-existing pocket of subretinal fluid ( P = 0.0093). However, the presence of subretinal fluid was not associated with the decision to proceed with any biopsy ( P = 0.36) or transvitreal biopsy specifically ( P = 1.00). By 3 months, subretinal and/or vitreous hemorrhage resolved in essentially all cases. There were no cases of iatrogenic retinal detachment or extraocular tumor spread over a mean follow-up of 41.7 (range: 20-62.1) months. Adequate tissue for gene expression profiling was obtained from each biopsy. The comparator group of patients undergoing transscleral biopsy including 21 uveal melanomas in 20 patients (one eye had two melanomas). Transvitreal biopsies were more common in patients with small (n = 15; P < 0.0001), posterior (n = 17; P < 0.0001) tumors, compared with patients who underwent transscleral biopsy during the same period. CONCLUSION: This technique can be used for small or posterior tumors or for small anterior tumors where a transscleral approach would risk tumor perforation. Complications were minor, transient, and self-limited. Biopsy yields for molecular prognosis were adequate in all cases. The presence of subretinal fluid may be considered a relative contraindication because it may lead to subretinal hemorrhage in the fluid pocket but did not dissuade us from using this transvitreal technique for patients who would benefit from it.

Ubiquitin ligase Wwp1 gene deletion attenuates diastolic dysfunction in pressure-overload hypertrophy.

Heart failure with a preserved left ventricular (LV) ejection fraction (HFpEF) often arises from a prolonged LV pressure overload (LVPO) and accompanied by abnormal extracellular matrix (ECM) accumulation. The E3 ubiquitin ligase WWP1 is a fundamental determinant ECM turnover. We tested the hypothesis that genetic ablation of Wwp1 would alter the progression of LVPO-induced HFpEF. LV echocardiography in mice with global Wwp1 deletion (n = 23; Wwp1-/-) was performed at 12 wk of age (baseline) and then at 2 and 4 wk following LVPO (transverse aortic banding) or surgery without LVPO induction. Age-matched wild-type mice (Wwp1+/+; n = 23) underwent identical protocols. LV EF remained constant and unchanged with LVPO and LV mass increased in both groups but was lower in the Wwp1-/- mice. With LVPO, the E/A ratio, an index of LV filling, was 3.97 ± 0.46 in Wwp1+/+ but was 1.73 ± 0.19 in the Wwp1-/- group (P < 0.05). At the transcriptional level, mRNA for fibrillar collagens (types I and III) decreased by approximately 50% in Wwp1-/- compared with the Wwp1+/+ group at 4 wk post-LVPO (P < 0.05) and was paralleled by a similar difference in LV fibrillar collagen content as measured by histochemistry. Moreover, mRNA levels for determinants favoring ECM accumulation, such as transforming growth factor (TGF), increased with LVPO, but were lower in the Wwp1-/- group. The absence of Wwp1 reduced the development of left ventricular hypertrophy and subsequent progression to HFpEF. Modulating the WWP1 pathway could be a therapeutic target to alter the natural history of HFpEF.NEW & NOTEWORTHY Heart failure with a preserved left ventricular (LV) ejection fraction (HFpEF) often arises from a prolonged LV pressure overload (LVPO) and is accompanied by abnormal extracellular matrix (ECM) accumulation. It is now recognized that the ECM is a dynamic entity that is regulated at multiple post-transcriptional levels, including the E3 ubiquitin ligases, such as WWP1. In the present study, WWP1 deletion in the context of an LVPO stimulus reduced functional indices of HFpEF progression and determinants of ECM remodeling.

Robotics in spine surgery: A systematic review.

Robotic systems to assist with pedicle screw placement have recently emerged in the field of spine surgery. Here, the authors systematically reviewed the literature for evidence of these robotic systems and their utility. Thirty-four studies that reported the use of spinal instrumentation with robotic assistance and met inclusion criteria were identified. The outcome measures gathered included: pedicle screw accuracy, indications for surgery, rates of conversion to an alternative surgical method, radiation exposure, and learning curve. In our search there were five different robotic systems identified. All studies reported accuracy and the most commonly used accuracy grading scale was the Gertzbein Robbins scale (GRS). Accuracy of clinically acceptable pedicle screws, defined as < 2 mm cortical breech, ranged from 80% to 100%. Many studies categorized indications for robotic surgery with the most common being degenerative entities. Some studies reported rates of conversion from robotic assistance to manual instrumentation due to many reasons, with robotic failure as the most common. Radiation exposure data revealed a majority of studies reported less radiation using robotic systems. Studies looking at a learning curve effect with surgeon use of robotic assistance were not consistent across the literature. Robotic systems for assistance in spine surgery have continued to improve and the accuracy of pedicle screw placement remains superior when compared to free-hand technique, however rates of manual conversion are significant. Currently, these systems are successfully employed in various pathological entities where trained spine surgeons can be safe and accurate regardless of robotic training.

Perioperative and swallowing outcomes in patients undergoing 4- and 5-level anterior cervical discectomy and fusion.

OBJECTIVE: Anterior cervical discectomy and fusion (ACDF) is a common and robust procedure performed on the cervical spine. Literature on ACDF for 4 or more segments is sparse. Increasing the number of operative levels increases surgical complexity, tissue retraction, and risks of complications, particularly dysphagia. The overall risks of these complications and rates of dysphagia are not well studied for surgery on 4 or more segments. In this study, the authors evaluated their institution's perioperative experience with 4- and 5-level ACDFs. METHODS: The authors retrospectively reviewed patients who underwent 4- or 5-level ACDF at their institution over a 6-year period (May 2013-May 2019). Patient demographics, perioperative complications, readmission rates, and swallowing outcomes were recorded. Outcomes were analyzed with a multivariate linear regression. RESULTS: A total of 174 patients were included (167 had 4-level and 7 had 5-level ACDFs). The average age was 60.6 years, and 54.0% of patients (n = 94) were men. A corpectomy was performed in 12.6% of patients (n = 22). After surgery, 56.9% of patients (n = 99) experienced dysphagia. The percentage of patients with dysphagia decreased to 22.8% (37/162) at 30 days, 12.9% (17/132) at 90 days, and 6.3% (5/79) and 2.8% (1/36) at 1 and 2 years, respectively. Dysphagia was more likely at 90 days postoperatively in patients with gastroesophageal reflux (OR 4.4 [95% CI 1.5-12.8], p = 0.008), and the mean (± SD) lordosis change was greater in patients with dysphagia than those without at 90 days (19.8° ± 13.3° vs 9.1° ± 10.2°, p = 0.003). Dysphagia occurrence did not differ with operative implants, including graft and interbody type. The mean length of time to solid food intake was 2.4 ± 2.1 days. Patients treated with dexamethasone were more likely to achieve solid food intake prior to discharge (OR 4.0 [95% CI 1.5-10.6], p = 0.004). Postsurgery, 5.2% of patients (n = 9) required a feeding tube due to severe approach-related dysphagia. Other perioperative complication rates were uniformly low. Overall, 8.6% of patients (n = 15) returned to the emergency department within 30 days and 2.9% (n = 5) required readmission, whereas 1.1% (n = 2) required unplanned return to surgery within 30 days. CONCLUSIONS: This is the largest series of patients undergoing 4- and 5-level ACDFs reported to date. This procedure was performed safely with minimal intraoperative complications. More than half of the patients experienced in-hospital dysphagia, which increased their overall length of stay, but dysphagia decreased over time.

Structure and noncanonical Cdk8 activation mechanism within an Argonaute-containing Mediator kinase module.

The Cdk8 kinase module (CKM) in Mediator, comprising Med13, Med12, CycC, and Cdk8, regulates RNA polymerase II transcription through kinase-dependent and -independent functions. Numerous pathogenic mutations causative for neurodevelopmental disorders and cancer congregate in CKM subunits. However, the structure of the intact CKM and the mechanism by which Cdk8 is non-canonically activated and functionally affected by oncogenic CKM alterations are poorly understood. Here, we report a cryo-electron microscopy structure of Saccharomyces cerevisiae CKM that redefines prior CKM structural models and explains the mechanism of Med12-dependent Cdk8 activation. Med12 interacts extensively with CycC and activates Cdk8 by stabilizing its activation (T-)loop through conserved Med12 residues recurrently mutated in human tumors. Unexpectedly, Med13 has a characteristic Argonaute-like bi-lobal architecture. These findings not only provide a structural basis for understanding CKM function and pathological dysfunction, but also further impute a previously unknown regulatory mechanism of Mediator in transcriptional modulation through its Med13 Argonaute-like features.

Mean arterial pressure maintenance following spinal cord injury: Does meeting the target matter?

INTRODUCTION: Neurosurgical guidelines recommend maintaining mean arterial pressure (MAP) between 85 and 90 mm Hg following acute spinal cord injury (SCI). In our hospital, SCI patients receive orders for MAP targeting for 72 hours following admission, but it is unclear how often the patient's MAP meets the target and whether or not this affects outcome. We hypothesized that the proportion of MAP measurements ≥85 mm Hg would be associated with neurologic recovery. METHODS: Spinal cord injury patients with blunt mechanism of injury admitted between 2014 and 2019 were identified from the registry of a level 1 trauma center. Proportion of MAP values ≥85 mm Hg was calculated for each patient. Neurologic improvement, as measured by positive change in American Spinal Injury Association (ASIA) impairment scale by ≥1 level from admission to discharge was evaluated with respect to proportion of elevated MAP values. RESULTS: A total of 136 SCI patients were evaluated. Average proportion of elevated MAP values was 75%. Admission ASIA grades were as follows: A, 30 (22.1%); B, 20 (14.7%); C, 28 (20.6%); and D, 58 (42.6%). One hundred six patients (77.9%) required vasopressors to elevate MAP (ASIA A, 86.7%; B, 95.0%; C, 92.9%; D, 60.3%). Forty patients (29.4%) were observed to have improvement in ASIA grade by discharge (admission ASIA A, 15%; B, 33%; C, 40%; D, 13%). The proportion of elevated MAP values was higher for patients with neurologic improvement (0.81 ± 0.15 vs. 0.72 ± 0.25, p = 0.014). Multivariate modeling demonstrated a significant association between proportion of elevated MAP values and neurologic improvement (p = 0.028). An interaction revealed this association to be moderated by vasopressor dose (p = 0.032). CONCLUSION: The proportion of MAP measurements ≥85 mm Hg was determined to be an independent predictor of neurologic improvement. Increased vigilance regarding MAP maintenance above 85 mm Hg is warranted to optimize neurologic recovery following SCI. LEVEL OF EVIDENCE: Therapeutic/care management, level IV.

Integrating Osteopathic Manipulative Treatment and Injections in the Diagnosis and Management of a Hip Labral Tear.

Hip pain in adults is a common complaint. Secondary processes can often mask underlying conditions, prolonging the course to diagnosis and definitive treatment. In this case, a 74-year-old man presented to an outpatient clinic after 6 weeks of right hip pain that began upon initiation of a rehabilitation program following coronary artery bypass graft surgery. Various imaging and treatment modalities (including radiography, osteopathic manipulative treatment, injection of the greater trochanteric bursa, L2-3 paravertebral block, magnetic resonance imaging, and intra-articular hip injection with 1% lidocaine) ultimately led to the definitive diagnosis of a labral tear. This case report highlights how a comprehensive osteopathic approach was used to evaluate and treat a patient with persistent unilateral hip pain because of an acetabular labral tear, associated psoas syndrome, and trochanteric bursitis, all within 2 months and with a positive clinical outcome.

Immunoglobulin G4-related disease in a dog.

Immunoglobulin G4-related disease (IgG4-RD), which affects many organ systems, has been recognized as a distinct clinical entity in human medicine for just over a decade but has not been previously identified in dogs. In humans, IgG4-RD is characterized by diffuse IgG4-positive lymphoplasmacytic infiltrates that commonly lead to increased serum concentrations of IgG4 and IgE, peripheral eosinophilia, tumorous swellings that often include the parotid salivary glands, obliterative phlebitis, and extensive fibrosis. Herein we describe the diagnosis, clinical progression, and successful treatment of IgG4-RD in an 8-year-old female spayed Husky mixed breed dog. Immunoglobulin G4-related disease should be considered as a differential diagnosis for dogs with vague clinical signs, lymphoplasmacytic swellings, restricted polyclonal gammopathy, eosinophilia or some combination of these findings.

External Choroidal Drainage Using Direct Visualization.

Laura L. Snyder Shriji N. Patel A woman in her 60s with a functional glaucoma tube shunt presented after vitrectomy for epiretinal membrane peeling with symptomatic choroidal effusions not responsive to medical therapy. She underwent a minimally invasive, transconjunctival choroidal drainage procedure, which was directly visualized under a widefield viewing system to prevent intraocular hemorrhage or retinal penetration of the needle. This allowed for preservation of her conjunctiva, restoration of normal intraocular pressure by temporary blockage of her tube shunt with a viscoelastic, and resolution of her choroidal effusions.

ACR Appropriateness Criteria® Cervical Neck Pain or Cervical Radiculopathy.

Nontraumatic neck pain is a leading cause of disability, with nearly 50% of individuals experiencing ongoing or recurrent symptoms. Radiographs are appropriate as initial imaging for cervical or neck pain in the absence of "red flag" symptoms or if there are unchanging chronic symptoms; however, spondylotic changes are commonly identified and may result in both false-positive and false-negative findings. Noncontrast CT can be complementary to radiographs for evaluation of new or changing symptoms in the setting of prior cervical spine surgery or in the assessment of extent of ossification in the posterior longitudinal ligament. Noncontrast MRI is usually appropriate for assessment of new or increasing radiculopathy due to improved nerve root definition. MRI without and with contrast is usually appropriate in patients with new or increasing cervical or neck pain or radiculopathy in the setting of suspected infection or known malignancy. Imaging may be appropriate; however, it is not always indicated for evaluation of cervicogenic headache without neurologic deficit. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Evaluation of Region of Interest Digital Cytology Compared to Light Microscopy for Veterinary Medicine.

Digital microscopy (DM) has been employed for primary diagnosis in human medicine and for research and teaching applications in veterinary medicine, but there are few veterinary DM validation studies. Region of interest (ROI) digital cytology is a subset of DM that uses image-stitching software to create a low-magnification image of a slide, then selected ROI at higher magnification, and stitches the images into a relatively small file of the embedded magnifications. This study evaluated the concordance of ROI-DM compared to traditional light microscopy (LM) between 2 blinded clinical pathologists. Sixty canine and feline cytology samples from a variety of anatomic sites, including 31 cases of malignant neoplasia, 15 cases of hyperplastic or benign neoplastic lesions, and 14 infectious/inflammatory lesions, were evaluated. Two separate nonblinded adjudicating clinical pathologists evaluated the reports and diagnoses and scored each paired case as fully concordant, partially concordant, or discordant. The average overall concordance (full and partial concordance) for both pathologists was 92%. Full concordance was significantly higher for malignant lesions than benign. For the 40 neoplastic lesions, ROI-DM and LM agreed on general category of tumor type in 78 of 80 cases (98%). ROI-DM cytology showed robust concordance with the current gold standard of LM cytology and is potentially a viable alternative to current LM cytology techniques.

A Quantitative Assessment of the Accuracy and Reliability of Robotically Guided Percutaneous Pedicle Screw Placement: Technique and Application Accuracy.

BACKGROUND: Minimally invasive surgery (MIS) and anterior (ALIF), transforaminal (TLIF), or lateral lumbar interbody fusion (LLIF) often require percutaneous pedicle screw fixation (PSF) to achieve circumferential fusion. Robotic guidance technology may augment workflow to improve screw placement and decrease operative time. OBJECTIVE: To report surgical experience with robotically assisted percutaneous screw placement following LLIF. METHODS: Data from fusions with robotically assisted PSF in prone or lateral decubitus positions was reviewed. A CT-guided robotic guidance arm was used for screw placement (Excelsius GPS™, Globus Medical Inc, Audubon, Pennsylvania). Postoperative CT imaging facilitated screw localization. 3-dimensional and 2-dimensional coordinates of the screw tip and tail were calculated and compared with a target trajectory to calculate targeting errors. Breach was defined as a violation of the lateral or medial pedicle wall. RESULTS: Robotic-guided screw placement was successful in 28/31 patients. In those patients, 116/116 screws were successfully implanted. The breach rate was 3.4% (4/116). Across 17 patients (70 screws), mean 3-D accuracy was 5.0 ± 2.4 mm, mean 2-D accuracy was 2.6 ± 1.1 mm, and mean angular offset was 5.6 ± 4.3° with corresponding intraclass correlation coefficients (ICC) of 0.775 and 0.693. 3-dimensional accuracy correlated with age (R = 0.306, P = .011) and BMI (R = 0.252, P = .038). Accuracy did not significantly differ among vertebral body levels (P > .22). Mean operative time for MIS-TLIF and percutaneous screws was 277 ± 52 and 183 ± 54 min, respectively. Operative time did not significantly decrease across either group (P > .187). CONCLUSION: The Excelsius GPS™ robotic guidance system allows accurate PSF in most cases with 2 mm 2-D accuracy. Future studies are needed to demonstrate the utility of this novel guidance system and workflow improvement.