Endoscopic precaruncular medial transorbital and endonasal multiport approaches to the contralateral skull base: a clinicoanatomical study.

OBJECTIVE: Minimally invasive endoscopic endonasal multiport approaches create additional visualization angles to treat skull base pathologies. The sublabial contralateral transmaxillary (CTM) approach and superior eyelid lateral transorbital approach, frequently used nowadays, have been referred to as the "third port" when used alongside the endoscopic endonasal approach (EEA). The endoscopic precaruncular contralateral medial transorbital (cMTO) corridor, on the other hand, is an underrecognized but unique port that has been used to repair CSF rhinorrhea originating from the lateral sphenoid sinus recess. However, no anatomical feasibility studies or clinical experience exists to assess its benefits and demonstrate its potential role in multiport endoscopic access to the other contralateral skull base areas. In this study, the authors explored the application and potential utility of multiport EEA combined with the endoscopic cMTO approach (EEA/cMTO) to three target areas of the contralateral skull base: lateral recess of sphenoid sinus (LRSS), petrous apex (PA) and petroclival region, and retrocarotid clinoidocavernous space (CCS). METHODS: Ten cadaveric specimens (20 sides) were dissected bilaterally under stereotactic navigation guidance to access contralateral LRSS via EEA/cMTO. The PA and petroclival region and retrocarotid CCS were exposed via EEA alone, EEA/cMTO, and EEA combined with the sublabial CTM approach (EEA/CTM). Qualitative and quantitative assessments, including working distance and visualization angle to the PA, were recorded. Clinical application of EEA/cMTO is demonstrated in a lateral sphenoid sinus CSF leak repair. RESULTS: During the qualitative assessment, multiport EEA/cMTO provides superior visualization from a high vantage point and better instrument maneuverability than multiport EEA/CTM for the PA and retrocarotid CCS, while maintaining a similar lateral trajectory. The cMTO approach has significantly shorter working distances to all three target areas compared with the CTM approach and EEA. The mean distances to the LRSS, PA, and retrocarotid CCS were 50.69 ± 4.28 mm (p < 0.05), 67.11 ± 5.05 mm (p < 0.001), and 50.32 ± 3.6 mm (p < 0.001), respectively. The mean visualization angles to the PA obtained by multiport EEA/cMTO and EEA/CTM were 28.4° ± 3.27° and 24.42° ± 5.02° (p < 0.005), respectively. CONCLUSIONS: Multiport EEA/cMTO to the contralateral LRSS offers the advantage of preserving the pterygopalatine fossa contents and the vidian nerve, which are frequently sacrificed during a transpterygoid approach. This approach also offers superior visualization and better instrument maneuverability compared with EEA/CTM for targeting the petroclival region and retrocarotid CCS.

Effectiveness of Nasolacrimal SCC Treatments and Promising Role of Chemo-Induction: A Case Report and Systematic Review.

OBJECTIVE: To comprehensively analyze reported cases of nasolacrimal squamous cell carcinoma (NLSCC), focusing on risk factors, treatment modalities, and outcomes. Additionally, investigate the impact of human Papillomavirus (HPV) status and histopathological subtypes' impact on prognosis. DATA SOURCES: Pubmed, Embase. REVIEW METHODS: We conducted a systematic literature review to identify relevant studies reporting cases of NLSCC. The review methods adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The final update was performed on May 31, 2023. RESULTS: The 72 studies included a total of 313 participants (mean age: 55; 60% male). Longer symptom duration (44.1 ± 59.2 months) correlated with recurrence (p = 0.004), and males exhibited higher mortality rates (19.6% vs. 2.4% in females, p = 0.01). The overall survival (OS) rate among all patients was 87.1%. Basaloid NLSCC had a worse death outcome (p ≤ 0.001). HPV-positive cases showed comparable OS, recurrence, and metastasis rates to the general population (p = 0.917, 0.851, 0.07, respectively). Comparing treatment approaches (surgery, surgery with adjuvant radiation, chemoradiotherapy [CRT] followed by surgery), no significant differences in 5 and 10-year OS rates or recurrence were observed (p = 0.4, 0.24, respectively), but 5-year metastasis events were significant (p = 0.024). Eye exenteration rates were 31.1%, 20%, and 0% for the respective treatments (p = 0.089). Induction chemotherapy saved four cases from potential exenteration with favorable prognosis. CONCLUSION: Early detection and diagnosis are of utmost importance in the management of NLSCC. Regardless of the treatment approach, HPV-related NLSCC demonstrated similar outcomes to the general population. Basaloid histology represents the worst subtype in terms of prognosis. Limited adjuvant CRT cases showed improved outcomes and induction chemotherapy's importance was emphasized in recent literature and our shared experience. Laryngoscope, 2024.

Assessing social vulnerabilities of salivary gland cancer care, prognosis, and treatment in the United States.

BACKGROUND: Salivary gland cancers (SGC)-social determinants of health (SDoH) investigations are limited by narrow scopes of SGC-types and SDoH. This Social Vulnerability Index (SVI)-study hypothesized that socioeconomic status (SES) most contributed to SDoH-associated SGC-disparities. METHODS: Retrospective cohort of 24 775 SGCs assessed SES, minority-language status (ML), household composition (HH), housing-transportation (HT), and composite-SDoH measured by the SVI via regressions with surveillance and survival length, late-staging presentation, and treatment (surgery, radio-, chemotherapy) receipt. RESULTS: Increasing social vulnerability showed decreases in surveillance/survival; increased odds of advanced-presenting-stage (OR: 1.12, 95% CI: 1.07, 1.17), chemotherapy receipt (OR: 1.13, 95% CI: 1.03, 1.23); decreased odds of primary surgery (0.89, 0.84, 0.94), radiotherapy (0.91, 0.85, 0.97, p = 0.003) for SGCs. Trends were differentially correlated with SES, ML, HH, and HT-vulnerabilities. CONCLUSIONS: Through quantifying SDoH-derived SGC-disparities, the SVI can guide targeted initiatives against SDoH that elicit the most detrimental associations for specific sociodemographics.

The characteristics and predictors of mortality in periprosthetic fractures around the knee.

Aims: Periprosthetic fractures (PPFs) around the knee are challenging injuries. This study aims to describe the characteristics of knee PPFs and the impact of patient demographics, fracture types, and management modalities on in-hospital mortality. Methods: Using a multicentre study design, independent of registry data, we included adult patients sustaining a PPF around a knee arthroplasty between 1 January 2010 and 31 December 2019. Univariate, then multivariable, logistic regression analyses were performed to study the impact of patient, fracture, and treatment on mortality. Results: Out of a total of 1,667 patients in the PPF study database, 420 patients were included. The in-hospital mortality rate was 6.4%. Multivariable analyses suggested that American Society of Anesthesiologists (ASA) grade, history of peripheral vascular disease (PVD), history of rheumatic disease, fracture around a loose implant, and cerebrovascular accident (CVA) during hospital stay were each independently associated with mortality. Each point increase in ASA grade independently correlated with a four-fold greater mortality risk (odds ratio (OR) 4.1 (95% confidence interval (CI) 1.19 to 14.06); p = 0.026). Patients with PVD have a nine-fold increase in mortality risk (OR 9.1 (95% CI 1.25 to 66.47); p = 0.030) and patients with rheumatic disease have a 6.8-fold increase in mortality risk (OR 6.8 (95% CI 1.32 to 34.68); p = 0.022). Patients with a fracture around a loose implant (Unified Classification System (UCS) B2) have a 20-fold increase in mortality, compared to UCS A1 (OR 20.9 (95% CI 1.61 to 271.38); p = 0.020). Mode of management was not a significant predictor of mortality. Patients managed with revision arthroplasty had a significantly longer length of stay (median 16 days; p = 0.029) and higher rates of return to theatre, compared to patients treated nonoperatively or with fixation. Conclusion: The mortality rate in PPFs around the knee is similar to that for native distal femur and neck of femur fragility fractures. Patients with certain modifiable risk factors should be optimized. A national PPF database and standardized management guidelines are currently required to understand these complex injuries and to improve patient outcomes.

Contralateral Nasofrontal Trephination: A Novel Corridor for a "Dual Port" Approach to the Petrous Apex.

BACKGROUND AND OBJECTIVES: Expanded endonasal approaches (EEAs) have proven safe and effective in treating select petrous apex (PA) pathologies. Angled endoscopes and instruments have expanded indications for such approaches; however, the complex neurovascular anatomy surrounding the petrous region remains a significant challenge. This study evaluates the feasibility, anatomic aspects, and limitations of a contralateral nasofrontal trephination (CNT) route as a complementary corridor improving access to the PA. METHODS: Expanded endonasal and CNT approaches to the PA were carried out bilaterally in 15 cadaveric heads with endovascular latex injections. The distance to the PA, angle between instruments through the 2 approach portals, and surgical freedom were measured and compared. RESULTS: Three-dimensional DICOM-based modeling and visualization indicate that the CNT route reduces the distance to the target located within the contralateral PA by an average of 3.33 cm (19%) and affords a significant increase in the angle between instruments (15.60°; 54%). Furthermore, the vertical vector of approach is improved by 28.97° yielding a caudal reach advantage of 2 cm. The area of surgical freedom afforded by 3 different approaches (endonasal, endonasal with an endoscope in CNT portal, and endonasal with an instrument in CNT portal) was compared at 4 points: the dural exit point of the 6th cranial nerve, jugular foramen, foramen lacerum, and petroclival fissure. The mean area of surgical freedom provided by both approaches incorporating the CNT corridor was superior to EEA alone at each of the surgical targets (P = <.001). CONCLUSION: The addition of a CNT portal provides an additional avenue to expand on the classical EEA to the PA. This study provides insight into the anatomic nuances and potential clinical benefits of a dual-port approach to the PA.

The Impact of the COVID-19 Pandemic on Orthopaedic Trauma Surgery in a District General Hospital in the United Kingdom.

Introduction The 2020 COVID-19 pandemic led to a national lockdown and a major reorganization of healthcare services in the United Kingdom. The center where the study was done was one of the worst affected hospitals in the United Kingdom at the outset of the pandemic. Our study evaluates the impact of the pandemic and national lockdown on the outcomes for patients undergoing orthopedic trauma surgery. Methods We prospectively identified all patients undergoing orthopedic trauma surgery in the unit from 1st March 2020 to 31st May 2020. We recorded demographics, diagnoses, COVID-19 infection status, length of stay, and mortality. This was compared with a comparative group in the same period in 2018 and 2019. Results There was a significant reduction in the number of orthopedic trauma surgery cases (318) performed in 2020 compared to 2019 (423 cases, p<0.001) and 2018 (444 cases, p<0.001). The mean time from injury to presentation was 3.6 days, with 40 patients (12.6%) presenting more than one week after injury. The 30-day mortality was 8.2%, and the six-month mortality was 15.1%, with both significantly higher than in 2018 (p<0.001) and 2019 (p<0.001). COVID-19 testing was positive in 39% of patients, with 30-day mortality in this group at 37%, rising to a 53% six-month mortality. No patients under the age of 50 years old died. The majority of admissions (51%) were due to falls at home. The second most common mechanism was Do-It-Yourself (DIY) injuries. Road traffic accidents accounted for 2%. Conclusion There were significantly fewer cases of orthopedic trauma surgery during the first wave of the COVID-19 pandemic compared to the same period in previous years. The type of trauma also showed low numbers of high-energy and sporting injuries as a result of the national lockdown. Patients undergoing orthopedic trauma surgery who tested positive for COVID-19 had significantly higher 30-day mortality than those without COVID-19, and this increased mortality persisted to six months post-operatively. However, patients under 50 years old appear to be at low risk of death.

Morphometric Comparison of Endoscopic Endonasal Transpterygoid and Precaruncular Contralateral Medial Transorbital Approaches to Sphenoid Sinus Lateral Recess.

BACKGROUND AND OBJECTIVES: The endoscopic endonasal transpterygoid approach (TPA), minimally invasive compared with the sublabial transmaxillary and transcranial approaches, still accounts for morbidity in benign lateral recess of sphenoid sinus (LRSS) pathologies. Others have suggested an alternative route to the LRSS, the endoscopic contralateral medial transorbital approach (cMTO). However, no quantitative evidence exists to support the clinical application of this approach. This cadaveric study, in a controlled laboratory setting, provides a morphometric comparison of the TPA and cMTO for accessing the LRSS. The study also details the anatomy and technical nuances for optimizing the cMTO corridor. METHODS: Ten fresh preinjected human cadaveric specimens (20 sides) were dissected with neuronavigation, completing endoscopic cMTO and TPA on each side. Four parameters-working distance to lateral recess, surgical exposure area, angle of attack (AoA), and surgical freedom-were measured for each approach. Relevant osteological measurements in 10 dried human skulls were recorded. RESULTS: The mean distance from the superior margin of the lacrimal sac impression to the inferior margin of the trochlear fossa was 10.29 ± 1.13 mm, and that from the anterior ethmoidal artery foramina to the posterior lacrimal crest was 9.63 ± 1.23 mm. The mean exposure area around the LRSS was significantly higher in TPA (614.09 ± 40.38 mm2) than in cMTO (391.19 ± 59.01 mm2, P = .001). The mean AoA was 9.83° and 10.24° in the cMTO and TPA, respectively, in the craniocaudal direction (P = .529). In the horizontal plane, it was 9.29° and 10.76° (P = .012). There was no significant difference in surgical freedom between the cMTO and TPA (804.61 and 806.05 mm3, respectively; P = .993). CONCLUSION: Although comparatively limited exposure area, the cMTO approach has a similar AoA and surgical freedom as TPA and offers better visualization and ergonomic advantages. cMTO provides a feasible, less morbid, multiport technique for benign sphenoid sinus lateral recess pathologies.

Impact of Predictive Text Clinical Decision Support on Imaging Order Entry in the Emergency Department.

PURPOSE: Imaging clinical decision support (CDS) is designed to assist providers in selecting appropriate imaging studies and is now federally required. The aim of this study was to understand the effect of CDS on decisions and workflows in the emergency department (ED). METHODS: The authors' institution's order entry platform serves up structured indications for imaging orders. Imaging orders are scored by CDS on the basis of appropriate use criteria (AUC). CDS triggers alerts for imaging orders with low AUC scores. Because free text alone cannot be scored by CDS, an artificial intelligence predictive text (AIPT) module was implemented to guide the selection of structured indications when free-text indications are entered. A total of 17,355 imaging orders in the ED over 6 months were retrospectively analyzed. RESULTS: CDS alerts for low AUC scores were triggered for 3% of all imaging study orders (522 of 17,355). Providers spent an average of 24 seconds interacting with alerts. In 18 of 522 imaging orders with alerts, alternative studies were ordered. After AIPT implementation, the percentage of unscored studies significantly decreased from 81% to 45% (P < .001). CONCLUSIONS: In a quaternary academic ED, CDS alerts triggered by low AUC scores caused minimal increase in time spent on imaging order entry but had a relatively marginal impact on imaging study selection. AIPT implementation increased the number of scored studies and could potentially enhance CDS effects. CDS implementation enables the collection of novel data regarding which imaging studies receive low AUC scores. Future work could include exploring alternative models of CDS implementation to maximize its impact.

Characteristics and risk factors of UCS fracture subtypes in periprosthetic fractures around the hip.

Aims: Periprosthetic fractures (PPFs) following hip arthroplasty are complex injuries. This study evaluates patient demographic characteristics, management, outcomes, and risk factors associated with PPF subtypes over a decade. Methods: Using a multicentre collaborative study design, independent of registry data, we identified adults from 29 centres with PPFs around the hip between January 2010 and December 2019. Radiographs were assessed for the Unified Classification System (UCS) grade. Patient and injury characteristics, management, and outcomes were compared between UCS grades. A multinomial logistic regression was performed to estimate relative risk ratios (RRR) of variables on UCS grade. Results: A total of 1,104 patients were included. The majority were female (57.9%; n = 639), ethnically white (88.5%; n = 977), used mobility aids (67%; n = 743), and had a median age of 82 years (interquartile range (IQR) 74 to 87). A total of 77 (7%) had pain prior to the PPF. The most common UCS grade was B2 (33%; n = 368). UCS type D fractures had the longest length of stay (median 19 days (IQR 11 to 26)), highest readmission to hospital (21%; n = 9), and highest rate of discharge to step-down care (52%; n = 23). Multinomial regression suggests that uncemented femoral stems are associated with a reduced risk of UCS C (RRR 0.36 (95% confidence interval (CI) 0.2 to 0.7); p = 0.002) and increased risk of UCS A (RRR 3.3 (95% CI 1.9 to 5.7); p < 0.001), compared to UCS B fracture. Conclusion: The most common PPF type in elderly frail patients is UCS B2. Uncemented stems have a lower risk of UCS C fractures compared to cemented stems. A national PPF database is needed to further identify correlation between implants and fracture subtypes.

The British Orthopaedic Oncology Management (BOOM) audit.

Aims: Most patients with advanced malignancy suffer bone metastases, which pose a significant challenge to orthopaedic services and burden to the health economy. This study aimed to assess adherence to the British Orthopaedic Oncology Society (BOOS)/British Orthopaedic Association (BOA) guidelines on patients with metastatic bone disease (MBD) in the UK. Methods: A prospective, multicentre, national collaborative audit was designed and delivered by a trainee-led collaborative group. Data were collected over three months (1 April 2021 to 30 June 2021) for all patients presenting with MBD. A data collection tool allowed investigators at each hospital to compare practice against guidelines. Data were collated and analyzed centrally to quantify compliance from 84 hospitals in the UK for a total of 1,137 patients who were eligible for inclusion. Results: A total of 846 patients with pelvic and appendicular MBD were analyzed, after excluding those with only spinal metastatic disease. A designated MBD lead was not present in 39% of centres (33/84). Adequate radiographs were not performed in 19% of patients (160/846), and 29% (247/846) did not have an up-to-date CT of thorax, abdomen, and pelvis to stage their disease. Compliance was low obtaining an oncological opinion (69%; 584/846) and prognosis estimations (38%; 223/846). Surgery was performed in 38% of patients (319/846), with the rates of up-to-date radiological investigations and oncology input with prognosis below the expected standard. Of the 25% (215/846) presenting with a solitary metastasis, a tertiary opinion from a MBD centre and biopsy was sought in 60% (130/215). Conclusion: Current practice in the UK does not comply with national guidelines, especially regarding investigations prior to surgery and for patients with solitary metastases. This study highlights the need for investment and improvement in care. The recent publication of British Orthopaedic Association Standards for Trauma (BOAST) defines auditable standards to drive these improvements for this vulnerable patient group.

Bifurcation cascade, self-similarity, and duality in the three-rotor problem.

The three-rotor system concerns equally massive point particles moving on a circle subject to attractive cosine potentials of strength g. The quantum theory models chains of coupled Josephson junctions. Classically, it displays order-chaos-order behavior with increasing energy E along with a seemingly globally chaotic phase for 5.33g≲E≲5.6g. It is also known to admit pendulum and isosceles breather families of periodic orbits at all energies. While pendula display a doubly infinite sequence of stability transitions accumulating at their libration to rotation threshold at E=4g, breathers undergo only one stability transition. Here, we show that these stability transitions are associated with forward and reverse fork-like isochronous and period-doubling bifurcations. The new family of periodic orbits born at each of these bifurcations is found using an efficient search algorithm starting from a transverse perturbation to the parent orbit. The graphs of stability indices of various classes of orbits born at pendulum bifurcations meet at E=4g forming "fans." The transitions in the librational and rotational phases are related by an asymptotic duality between bifurcation energies and shapes of newly born periodic orbits. The latter are captured by solutions to a Lamé equation. We also find and numerically validate values of scaling constants for self-similarity in (a) stability indices of librational and rotational pendula and (b) shapes of newly born orbits as E→4g. Finally, we argue that none of the infinitely many families of periodic orbits we have found is stable for 5.33g≲E≲5.6g, providing further evidence for global chaos in this energy band.

Endoscopic Endonasal Transcavernous Posterior Clinoidectomy With Inferior Hypophyseal Artery Preservation for a Cavernous Sinus Hemangioma: Technical Case Report.

BACKGROUND AND IMPORTANCE: Unilateral inferior hypophyseal artery (IHA) sacrifice is routinely performed during endoscopic endonasal transcavernous interdural posterior clinoidectomy. However, unilateral IHA sacrifice presents the risk of temporary postoperative diabetes insipidus. We present a case demonstrating the feasibility of endoscopic endonasal transcavernous posterior clinoidectomy without IHA sacrifice. CLINICAL PRESENTATION: A 62-year-old man presented with progressive weakness of his left oculomotor and abducens nerves. MRI of the brain revealed a small lesion suspicious for hemangioma in the posterior compartment of the left cavernous sinus. Following an endoscopic endonasal transcavernous approach using the interdural peeling technique, an IHA-sparing posterior clinoidectomy was performed to provide access to the tumor in the posterior cavernous sinus. After complete resection, the patient's symptoms improved and a diagnosis of cavernous sinus hemangioma was confirmed by histopathology. CONCLUSION: Unilateral IHA preservation may be performed safely when performing a transcavernous interdural posterior clinoidectomy. IHA preservation can be readily achieved if the artery is redundant, the lesion is small and located in the posterior cavernous sinus, and there is a short posterior clinoid, ultimately avoiding the risk of transient postoperative diabetes insipidus.

Multienzyme activity profiling for evaluation of cell-to-cell variability of metabolic state.

In solid organs, cells of the same "type" can vary in their molecular phenotype. The basis of this state variation is being revealed by characterizing cell features including the expression pattern of mRNAs and the internal distribution of proteins. Here, the variability of metabolic state between cells is probed by enzyme activity profiling. We study individual cells of types that can be identified during the post-mitotic phase of oogenesis in Xenopus laevis. Whole-cell homogenates of isolated oocytes are used for kinetic analysis of enzymes, with a focus on the initial reaction rate. For each oocyte type studied, the activity signatures of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and malate dehydrogenase 1 (MDH1) vary more between the homogenates of single oocytes than between repeat samplings of control homogenates. Unexpectedly, the activity signatures of GAPDH and MDH1 strongly co-vary between oocytes of each type and change in strength of correlation during oogenesis. Therefore, variability of the kinetic behavior of these housekeeping enzymes between "identical" cells is physiologically programmed. Based on these findings, we propose that single-cell profiling of enzyme kinetics will improve understanding of how metabolic state heterogeneity is related to heterogeneity revealed by omics methods including proteomics, epigenomics, and metabolomics.

Revising the Indications of Transtemporal Surgical Approaches in the Modern Endoscopic Era of Skull Base Surgery: A Dying Art.

Objectives The aim of the study is to emphasize and explore the possible transtemporal approaches for spectrum of complicated lateral skull base pathologies. Design Retrospective analysis of complicated lateral skull base pathologies was managed in our institute between January 2017 and December 2019. Setting The study was conducted in a tertiary care referral center. Main Outcome Measures The study focused on the selection of approach based on site and extent of the pathology, the surgical nuances for each approach, and the associated complications. Results A total of 10 different pathologies of the lateral skull base were managed by different transtemporal approaches. The most common complication encountered was facial nerve palsy (43%, n = 6). Other complications included cerebrospinal fluid (CSF) collection (15%, n = 2), cosmetic deformity (24%, n = 4), petrous internal carotid artery injury (7%, n = 1), and hypoglossal nerve palsy (7%, n = 1). The cosmetic deformity included flap necrosis ( n = 2) and postoperative bony defects leading to contour defects of the scalp ( n = 2). Conclusion Surgical approach should be tailored based on the individual basis, to obtain adequate exposure and complete excision. Selection of appropriate surgical approach should also be based on the training and preference of the operating surgeon. Whenever necessary, combined surgical approaches facilitating full tumor exposure are recommended so that complete tumor excision is feasible. This requires a multidisciplinary team comprising neurosurgeons, neuro-otologist, neuroanesthetist, and plastic surgeons. The surgeon must know precise microsurgical anatomy to preserve the adjacent nerves and vessels, which is necessary for better surgical outcomes.

Economic impact of selective use of contrast for routine follow-up MRI of patients with multiple sclerosis.

BACKGROUND AND PURPOSE: Imaging and autopsy studies show intracranial gadolinium deposition in patients who have undergone serial contrast-enhanced MRIs. This observation has raised concerns when using contrast administration in patients who receive frequent MRIs. To address this, we implemented a contrast-conditional protocol wherein gadolinium is administered only for multiple sclerosis (MS) patients with imaging evidence of new disease activity on precontrast imaging. In this study, we explore the economic impact of our new MRI protocol. METHODS: We compared scanner time and Medicare reimbursement using our contrast-conditional methodology versus that of prior protocols where all patients received gadolinium. RESULTS: For 422 patients over 4 months, the contrast-conditional protocol amounted to 60% decrease in contrast injection and savings of approximately 20% of MRI scanner time. If the extra scanner time was used for performing MS follow-up MRIs in additional patients, the contrast-conditional protocol would amount to net revenue loss of $21,707 (∼3.7%). CONCLUSIONS: Implementation of a new protocol to limit contrast in MS follow-up MRIs led to a minimal decrease in revenue when controlled for scanner time utilized and is outweighed by other benefits, including substantial decreased gadolinium administration, increased patient comfort, and increased availability of scanner time, which depending on type of studies performed could result in additional financial benefit.

Cationic surfactant assisted enhancement of dielectric and piezoelectric properties of PVDF nanofibers for energy harvesting application.

Poly(vinylidene fluoride) (PVDF) is among the most versatile polymers due to its wide range of properties, including dielectric, piezoelectric and ferroelectric properties. However, more frequently than not a range of processing routes and/or additives have been used to enhance such properties. In this study, PVDF nanofibers were electrospun from PVDF solution that contained tetra-n-butyl ammonium chloride (TBAC) at different loadings (1, 2, 3, and 5 wt%). The effect of TBAC on the morphology, crystallinity, and polymorphism of PVDF was studied using various characterization techniques. Addition of TBAC significantly improved the electroactive ß-phase of PVDF. The highest ß-phase content of 89% was attained at a TBAC loading of 3 wt%. Consequently, the dielectric and piezoelectric properties of the PVDF nanofibers improved significantly. A nanogenerator fabricated using 3 wt% TBAC/PVDF nanofibers exhibited the maximum voltage output of 17.2 V (under 5 N force) and the maximum power density of ∼1.4 µW cm-2 (under 3 N force). Improved dielectric and piezoelectric properties of PVDF upon the addition of a small amount of TBAC could be useful for researchers in upbringing the material for flexible electronic devices.

Cost-Effectiveness and Patient Outcomes of Injectable Collagenase to Treat Dupuytren's Contracture.

Introduction Dupuytren's contracture is a disabling and progressive flexion contracture of the hand that is often treated by a surgical release. Collagenase clostridium histolyticum injection (CCH-I) was introduced to the UK in 2011 as an alternative and less invasive treatment for contracture. The purpose of this study was to evaluate the cost-effectiveness and patient-reported outcome measures (PROMs) of treating Dupuytren's contracture with collagenase compared to surgery. Methods A retrospective review identified 151 patients who underwent CCH-I (n=94), limited fasciectomy (LF; n=38) and percutaneous needle fasciotomy (PNF; n=19). Outcomes included PROMs (satisfaction, QuickDASH), complication rates (recurrence, reintervention) and direct costs. Results Standardised treatment costs for CCH-I, LF and PNF were £1,125.82, £3,438.28 and £1,143.32 respectively. Collagenase presented a cost-benefit of £88,205 had the LF/PNF group undergone CCH-I. At a mean six-year follow-up, there were no significant differences in complication rates (=0.621) or QuickDASH scores (p=0.157). Collagenase-treated patients reported the highest satisfaction and lowest recurrence rates. Discussion Collagenase presents a significant cost reduction with superior PROMs relative to surgery for treating single-digit contracture. Conclusion Outpatient CCH-I is a cost-effective treatment with fewer clinical encounters, a similar risk profile to LF/PNF and high levels of patient satisfaction, which warrants serious consideration in light of overburdened waiting lists due to COVID-19.

99mTc-Mebrofenin SPECT/CT in Hepatic Infarction.

A 68-year-old man with hereditary hypercoagulability was referred to nuclear medicine for elevated aminotransferases after a recent living-donor liver transplant. A hepatic infarction was suspected. A Tc-mebrofenin SPECT/CT was performed and showed decreased radiotracer uptake in a wedge-shaped distribution in the anterior liver suggestive of a hepatic infarction. Subsequently, an enhanced MRI corroborated the diagnosis. Oral anticoagulation therapy was then initiated, and aminotransferases soon normalized.

The relationship between measures of spinal deformity and measures of thoracic trunk rotation.

BACKGROUND: Adolescent idiopathic scoliosis (AIS) is associated with both asymmetry of the torso (rib hump) and vertebral body rotation (VBR). Current surgical techniques aim to reduce the VBR and rib hump. However, it is not clear how the vertebral rotation and thoracic asymmetry are linked. METHODS: A retrospective cohort study was performed in which all adolescent patients with a diagnosis of AIS (Lenke curve type one to four only), a minimum 2-year follow up and a complete data set of radiographs, Integrated Shape Imaging System 2 (ISIS2) surface topography and axial imaging within a 6-week period were included. The Cobb angle was obtained from the radiograph, the maximum VBR was measured from the axial imaging using the Aaro and Dahlborn technique and the largest maximum skin angle (MSA) was taken from the ISIS2 topography. MSA is the ISIS2 parameter and is similar in nature to a scoliometer. RESULTS: From the surface topography database of AIS, 51 met the inclusion criteria. There were 6 males and 45 females with a mean age of 14.6 years (SD 1.4, range, 11.2 to 17.7). The mean Cobb angle was 54.4° (SD 13.8°, range, 29° to 92°). Mean MSA was 11.7° (SD 4.0°, range, 4° to 23°). Mean VBR was 14.3° (SD 4.3°, range, 8° to 24°). Through linear regression techniques, the relationships between Cobb angle, MSA and VBR were examined. The R2 between Cobb angle and MSA was 9%, between Cobb angle and VBR was 23% and between MSA and VBR was 16%. A multiple regression analysis did not improve these results. CONCLUSIONS: Whilst AIS features both VBR and torso asymmetry, they are poorly related to each other. This may help to explain why surgical de-rotation of the spine does not fully address the rib hump as other factors, yet to be defined, must be involved.