Isolation of the Stromal Vascular Fraction Using a New Protocol with All Clinical-Grade Drugs: From Basic Study to Clinical Application.

OBJECTIVE: The purpose of this study was to evaluate the yield, viability, clinical safety, and efficacy of the stromal vascular fraction (SVF) separated with a new protocol with all clinical-grade drugs. MATERIALS AND METHODS: SVF cells were isolated from lipoaspirate obtained from 13 participants aged from 30 to 56 years by using a new clinical protocol and the laboratory protocol. The cell yield, viability, morphology, mesenchymal stem cell (MSC) surface marker expression, and differentiation abilities of the SVF cells harvested from the two protocols were compared. Furthermore, three related clinical trials were conducted to verify the safety and efficiency of SVF cells isolated by the new clinical protocol. RESULTS: There were no significant differences in the yield, viability, morphology, and differentiation potential of the SVFs isolated with the clinical protocol and laboratory protocol. Adipose-derived mesenchymal stem cell (ASC) surface marker expression, including that of CD14, CD31, CD44, CD90, CD105, and CD133, was consistent between the two protocols. Clinical trials have demonstrated the effectiveness of the SVF isolated with the new clinical protocol in improving skin grafting, promoting mechanical stretch-induced skin regeneration and improving facial skin texture. No complications occurred. CONCLUSION: SVF isolated by the new clinical protocol had a noninferior yield and viability to that of the SVF separated by the laboratory protocol. SVFs obtained by the new protocol can be safely and effectively applied to improve skin grafting, promote mechanical stretch-induced skin regeneration, and improve facial skin texture. TRIAL REGISTRATION: The trials were registered with the ClinicalTrials.gov (NCT03189628), the Chinese Clinical Trial Registry (ChiCTR2000039317), and the ClinicalTrials.gov (NCT02546882). All the three trials were not patient-funded trials. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Therapeutic targeting of white adipose tissue metabolic dysfunction in obesity: mechanisms and opportunities.

White adipose tissue is not only a highly heterogeneous organ containing various cells, such as adipocytes, adipose stem and progenitor cells, and immune cells, but also an endocrine organ that is highly important for regulating metabolic and immune homeostasis. In individuals with obesity, dynamic cellular changes in adipose tissue result in phenotypic switching and adipose tissue dysfunction, including pathological expansion, WAT fibrosis, immune cell infiltration, endoplasmic reticulum stress, and ectopic lipid accumulation, ultimately leading to chronic low-grade inflammation and insulin resistance. Recently, many distinct subpopulations of adipose tissue have been identified, providing new insights into the potential mechanisms of adipose dysfunction in individuals with obesity. Therefore, targeting white adipose tissue as a therapeutic agent for treating obesity and obesity-related metabolic diseases is of great scientific interest. Here, we provide an overview of white adipose tissue remodeling in individuals with obesity including cellular changes and discuss the underlying regulatory mechanisms of white adipose tissue metabolic dysfunction. Currently, various studies have uncovered promising targets and strategies for obesity treatment. We also outline the potential therapeutic signaling pathways of targeting adipose tissue and summarize existing therapeutic strategies for antiobesity treatment including pharmacological approaches, lifestyle interventions, and novel therapies.

Quantitative HBeAg is a strong predictor of HBeAg loss among patients receiving pegylated interferon.

BACKGROUND: HBeAg loss is an important endpoint for antiviral therapy in chronic hepatitis B (CHB), however there are no reliable biomarkers to identify patients who will respond to the addition of pegylated interferon to nucleos(t)ide analogue (NA) therapy. AIM: To evaluate the use of serum biomarkers to predict HBeAg loss. METHODS: HBeAg positive CHB participants on NAs who switched-to or added-on 48 weeks pegylated interferon alpha2b (clinicaltrial.gov NCT01928511) were evaluated at week 72 for HBeAg loss. The predictive ability of qHBeAg, qHBsAg, HBV RNA and clinical variables for HBeAg loss were investigated. RESULTS: HBeAg loss occurred in 15/55 (27.3%) participants who completed 48 weeks of pegylated interferon. There was a lower baseline qHBeAg (1.18 IU/mL [2.27] versus 10.04 IU/mL [24.87], P = 0.007) among participants who lost HBeAg. Baseline qHBeAg (OR = 0.15, 95% CI 0.03-0.66, P = 0.01) and detectable HBV DNA at baseline (OR = 25.00, 95% CI 1.67-374.70, P = 0.02) were independent predictors of HBeAg loss. In addition, on-treatment qHBeAg was also a strong predictor of HBeAg loss (OR = 0.39, 95% CI 0.18-0.81, P = 0.012). The models combining detectable baseline HBV DNA with baseline (C-statistic 0.82) and on-treatment (C-statistic 0.83) had good accuracy for predicting HBeAg loss. A rise in qHBeAg ≥ 10 IU/ml was a predictor of flare (ALT ≥ 120 U/ml) on univariable analysis but not after adjustment for treatment arm. CONCLUSIONS: Baseline and on-treatment qHBeAg is a useful biomarker that can identify participants on NA therapy who may benefit from adding or switching to pegylated interferon.

Wunderlich syndrome in a patient with pyelonephritis.

An elderly female patient with left pyelonephritis developed worsening left flank pain, hypotension and a drop in haemoglobin (Hb) from 97 g/L to 67g/L on the third day of her admission. There was no recent trauma, history of coagulopathy or risk factors for renal malignancy or vascular disease.A contrasted CT scan of the kidneys revealed a 3.8 cm left renal subcapsular haematoma with no active contrast extravasation. Her atraumatic subcapsular haematoma fulfils two out of three clinical features of Lenk's triad (acute flank pain, hypovolaemic shock), suggestive of Wunderlich syndrome. Urine and blood cultures grew Klebsiella pneumoniae and she was managed conservatively with culture-directed antibiotics, fluids and blood products.Wunderlich syndrome is a rare complication of pyelonephritis and should be considered in patients with pyelonephritis who develop acute severe flank pain, Hb drop and haemodynamic instability. Appropriate medical and surgical therapies need to be instituted early to ensure good outcomes.

Dual therapy of cancer using optimal control supported by swarm intelligence.

BACKGROUND: The scientific revolution in the treatment of many illnesses has been significantly aided by stem cells. This paper presents an optimal control on a mathematical model of chemotherapy and stem cell therapy for cancer treatment. OBJECTIVE: To develop effective hybrid techniques that combine the optimal control theory (OCT) with the evolutionary algorithm and multi-objective swarm algorithm. The developed technique is aimed to reduce the number of cancerous cells while utilizing the minimum necessary chemotherapy medications and minimizing toxicity to protect patients' health. METHODS: Two hybrid techniques are proposed in this paper. Both techniques combined OCT with the evolutionary algorithm and multi-objective swarm algorithm which included MOEA/D, MOPSO, SPEA II and PESA II. This study evaluates the performance of two hybrid techniques in terms of reducing cancer cells and drug concentrations, as well as computational time consumption. RESULTS: In both techniques, MOEA/D emerges as the most effective algorithm due to its superior capability in minimizing tumour size and cancer drug concentration. CONCLUSION: This study highlights the importance of integrating OCT and evolutionary algorithms as a robust approach for optimizing cancer chemotherapy treatment.

Tracing the Change and Contribution of Subcutaneous Adipose to Skin Expansion Using a Luciferase-Transgenic Fat Transplantation Model.

BACKGROUND: During skin expansion, subcutaneous adipose tissue undergoes the greatest change. The adipose layer appears to gradually thin or even disappear in long-term expansion. The response and contribution of adipose tissue to skin expansion remain to be elucidated. METHODS: The authors established a novel expansion model by transplanting luciferase-transgenic adipose tissue into the rat dorsum, followed by integrated expansion, to trace the dynamic changes in subcutaneous adipose tissue during expansion and the migration of adipose tissue-derived cells. In vivo luminescent imaging was performed to continuously track the adipose tissue changes. Histologic analysis and immunohistochemical staining evaluated the regeneration and vascularization of the expanded skin. Growth factor expression in expanded skin with or without adipose tissue was determined to evaluate the paracrine effect of adipose tissue. Adipose tissue-derived cells were traced in vitro by anti-luciferase staining, and their fate was determined by costaining for PDGFRα, DLK1, and CD31. RESULTS: In vivo bioimaging showed that cells in adipose tissue were alive during expansion. After expansion, the adipose tissue exhibited fibrotic-like structures, with more DLK1 + preadipocytes. Skin expanded with adipose tissue was significantly thicker than that without adipose tissue, with more blood vessels and cell proliferation. Vascular endothelial growth factor, epidermal growth factor, and basic fibroblast growth factor expression was higher in adipose tissue than in skin, indicating paracrine support from adipose tissue. Luciferase-positive adipose tissue-derived cells were observed in expanded skin, indicating direct participation in skin regeneration. CONCLUSION: Adipose tissue transplantation can effectively promote long-term skin expansion by contributing to vascularization and cell proliferation by means of various mechanisms. CLINICAL RELEVANCE STATEMENT: The authors' findings suggest that it would be better if the expander pocket is dissected over the superficial fascia to preserve a layer of adipose tissue with skin. In addition, their findings support the treatment of fat grafting when expanded skin presents with thinning.

Incidence, severity, and temporal development of oral complications in pediatric allogeneic hematopoietic stem cell transplant patients - a multicenter study.

PURPOSE: Oral mucositis is a common complication for patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT) and causes pain and difficulties in functions like eating and swallowing, resulting in lower quality of life and greater need of treatment with opioids and parenteral nutrition. This prospective multicenter study focused on pediatric recipients of HSCT in the neutropenic phase concerning oral complications, timing, severity, and patient experience. METHODS: The cohort comprised 68 patients, median age 11.1 years (IQR 6.3) receiving allogeneic HSCT at three clinical sites. Medical records were retrieved for therapy regimens, concomitant medications, oral and dental history, and subjective oral complaints. Calibrated dentists conducted an oral and dental investigation before HSCT. After HSCT graft infusion, study personnel made bedside assessments and patients filled out a questionnaire once or twice a week until neutrophil engraftment. RESULTS: We followed 63 patients through the neutropenic phase until engraftment. 50% developed oral mucositis of grades 2-4. Peak severity occurred at 8-11 days after stem cell infusion. Altogether, 87% had subjective oral complaints. The temporal distribution of adverse events is similar to the development of oral mucositis. The most bothersome symptoms were blisters and oral ulcerations, including mucositis; 40% reported severe pain and major impact on activities of daily living despite continuous use of opioids. CONCLUSION: This study highlights the burden of oral complications and their negative effect on the health and quality of life of HSCT recipients.

Does information on age-related fertility decline and fertility policies affect university students' family and career expectations? Evidence from a randomized controlled trial.

BACKGROUND: Past research shows that young adults have poor knowledge of age-related fertility decline and that the provision of information can improve fertility knowledge. We provide university students with information on age-related fertility and fertility-related policies and investigate whether the provision of such information affects their family formation and career expectations. METHODS: A three-armed randomized controlled trial was conducted online in Singapore between September and October 2021. A total of 1000 undergraduate students were recruited through campus advertisements to complete a 30- to 45-minute online survey, which randomly exposed participants to one of three informational brochures on age-related fertility decline, fertility policies, or diabetes (control group). Participants answered questions on family formation and career expectations both before and after the information intervention. Analysis of covariance was used to assess the effects of the information intervention. RESULTS: Exposure to age-related fertility information resulted in significant reductions in the ideal age at first childbirth, significant increases in the expected probability of marriage before age 30, and (among female participants) significant increases in the expected likelihood of undergoing social egg-freezing. No difference existed in child-number ideals, educational aspirations, and income expectations between groups after exposure. No difference existed between the fertility policy information group and the control group after exposure in any of the outcomes of interest. CONCLUSIONS: Information on age-related fertility decline brought forward university students' expected timing of childbearing and marriage without reducing their educational and career expectations. The provision of fertility information at early ages, such as during university, can help correct widespread inaccurate beliefs about fertility and promote realistic family formation planning without adversely affecting educational and career goals. TRIAL REGISTRATION: ClinicalTrials.gov.

Identifying characteristics of dermal fibroblasts in skin homeostasis and disease.

Heterogeneous dermal fibroblasts are the main components that constitute the dermis. Distinct fibroblast subgroups show specific characteristics and functional plasticity that determine dermal structure during skin development and wound healing. Although researchers have described the roles of fibroblast subsets, this is not completely understood. We review recent evidence supporting understanding about the heterogeneity of fibroblasts. We summarize the origins and the identified profiles of fibroblast subpopulations. The characteristics of fibroblast subpopulations in both healthy and diseased states are highlighted, and the potential of subpopulations to be involved in wound healing in different ways was discussed. Additionally, we review the plasticity of subpopulations and the underlying signalling mechanisms. This review may provide greater insights into potential novel therapeutic targets and tissue regeneration strategies for the future.

A reinforced framework construction technique using unilateral auricular cartilage in Asian rhinoplasty to prevent long-term nasal tip drooping.

BACKGROUND: Enhancing nasal tip projection is an important objective in Asian rhinoplasty. Nasal tip enhancement using auricular cartilage is simple and suitable for Asian patients. However, the long-term retraction problem of the auricular framework still needs to be solved for optimal results. OBJECTIVES: The authors propose a modified auricular cartilage framework construction technique that provides stronger long-term support to the nasal tip and columellar base. METHODS: Eighty-one patients underwent augmentation rhinoplasty between January 2016 and December 2019. The cymba and cavum conchae were harvested from one ear in all cases. The cymba concha was carved and folded to form a caudal septal extension graft (CSEG). The cavum concha was divided into an integrated cap/shield graft and a columella base graft. The columella base graft was diced into particles in size of 1 mm3, and inserted into the gap between CSEG, anterior nasal spine, and the medial crus to strengthen the foundation. The nasal profile was analyzed before the operation and at least 12 months after the operation. The patient satisfaction score was assessed 12 months after surgery. RESULTS: Patients were followed up for 12-36 months. The nasal tip projection from both the lateral and basal views was significantly improved. The columella-labial angle was increased from 83.15° (6.20°) to 96.50° (7.40°) (p < 0.05). The nostril tip proportion increased from 0.83 (0.14) to 1.17(0.16) (p < 0.01). A stable long-term outcome was achieved. CONCLUSIONS: With the modified framework construction technique, long-term nasal tip drooping can be prevented. This method can be a practical choice for Asian patients seeking augmentation rhinoplasty.

Concentrated ultrasound-processed fat (CUPF): More than a mechanically emulsified graft.

INTRODUCTION: Autologous fat grafting is still an evolving technique. Researchers have attempted to increase the survival rate of grafts by concentrating adipose-derived stem cells (ASCs). In this study, we investigate a novel method that combines ultrasonic processing and centrifugation to generate small fat particles termed concentrated ultrasound-processed fat (CUPF) for grafting. METHODS: The standard approach for obtaining CUPF is described. The properties of processed fat, including CUPF, microfat, centrifuged fat, and nanofat, were investigated using histological observation. Comparative analyses were conducted on the cell number, viability, and immunophenotypic profile of stromal vascular fraction cells (SVFs). Cultured ASCs were evaluated for cell proliferation and adipogenic, osteogenic, and chondrogenic potential. The processed fats were transplanted and evaluated using in vivo and histological studies. RESULTS: Compared with microfat, centrifuged fat, and nanofat, CUPF had a condensed tissue content and higher concentration of viable cells in a small tissue structure and could smoothly pass through a 27-gauge cannula. In the CUPF group, SVFs were isolated in great numbers, with high viability and a high proportion of CD29- and CD105-positive cells. ASCs from the CUPF group exhibited high proliferation and multilineage differentiation potential. The grafts from the CUPF group were well preserved, and histological quantification revealed an increase in the abundance of Ki67- and CD31-positive cells in the tissue. CONCLUSIONS: Our study established a new fat processing strategy that combines ultrasonic processing and centrifugation to harvest small particle grafts named CUPF. CUPF concentrated a large number of ASCs and has great potential for regenerative therapy.

Long-Term Air Pollution Characteristics and Multi-scale Meteorological Factor Variability Analysis of Mega-mountain Cities in the Chengdu-Chongqing Economic Circle.

Currently, air quality has become central to global environmental policymaking. As a typical mountain megacity in the Cheng-Yu region, the air pollution in Chongqing is unique and sensitive. This study aims to comprehensively investigate the long-term annual, seasonal, and monthly variation characteristics of six major pollutants and seven meteorological parameters. The emission distribution of major pollutants is also discussed. The relationship between pollutants and the multi-scale meteorological conditions was explored. The results indicate that particulate matter (PM), SO2 and NO2 showed a "U-shaped" variation, while O3 showed an "inverted U-shaped" seasonal variation. Industrial emissions accounted for 81.84%, 58% and 80.10% of the total SO2, NOx and dust pollution emissions, respectively. The correlation between PM2.5 and PM10 was strong (R = 0.98). In addition, PM only showed a significant negative correlation with O3. On the contrary, PM showed a significant positive correlation with other gaseous pollutants (SO2, NO2, CO). O3 is only negatively correlated with relative humidity and atmospheric pressure. These findings provide an accurate and effective countermeasure for the coordinated management of air pollution in Cheng-Yu region and the formulation of the regional carbon peaking roadmap. Furthermore, it can improve the prediction accuracy of air pollution under multi-scale meteorological factors, promote effective emission reduction paths and policies in the region, and provide references for related epidemiological research. Supplementary Information: The online version contains supplementary material available at 10.1007/s11270-023-06279-8.

A Pilot Study on Pharmacists' Knowledge, Attitudes and Practices towards Medication Dysphagia via Asynchronous Online Focus Group Discussion.

Medication dysphagia (MD) refers to difficulty swallowing oral medications. To cope, patients may inappropriately modify or skip medications, leading to poorer outcomes. Little is known about healthcare professionals' (HCPs') perspectives in managing MD. This study investigated pharmacists' knowledge, attitudes, and practices (KAP) in caring for patients with MD. An asynchronous online focus group was pilot tested in seven pharmacists, with up to two questions posted daily on an online platform over 15 days. Thematic analysis of the transcripts revealed five interrelated themes: (1) knowledge about MD; (2) management of MD; (3) expectations of patient proactivity; (4) desire for objectivity; (5) professional roles. The findings provided insight into pharmacists' KAP and may be incorporated into a full-scale study involving various HCPs.

Performance of portable objective wound assessment tools: a systematic review.

OBJECTIVE: Accurate wound assessment is crucial for determining the progression of healing and guides treatment strategies. Portable wound assessment devices can be useful in providing an accurate evaluation in the community where most cases are treated. The objective of this review was to compare the performance of various portable wound assessment techniques used for wound healing assessment described in the literature. METHOD: In April 2020, electronic databases were searched, using appropriate search terms, for all available publications on the use of portable wound assessment devices on human and artificial wounds. The primary outcome was the reliability and reproducibility of measurement while the secondary outcome was the feasibility of the instrument. All studies underwent quality assessment of diagnostic accuracy studies (QUADAS) to examine the quality of data. RESULTS: A total of 129 articles were identified and 24 were included in the final review; 17 articles discussed two-dimensional (2D) devices; three articles discussed three-dimensional (3D) devices; and four articles discussed application-based devices. Most studies (n=8) reported on a 2D device that had an ICC of 0.92-0.99 for area measurement and a coefficient of variance of 3.1% with an error of 2.3% in human wounds and 1.55-3.7% in artificial wounds. The inter/intra observer reliability was 0.998 and 0.985, respectively with a scan time of two minutes per wound. The median QUADAS score was 12. CONCLUSION: Based on the presented evidence, 2D-based portable wound assessment devices were the most studied and demonstrated good performance. Further studies are required for 3D and application-based measurement instruments.

Autologous Concentrated Growth Factor Increases Skin Thickness and Area during Tissue Expansion: A Randomized Clinical Trial.

BACKGROUND: Mechanical stretching of the skin (ie, tissue expansion) could generate additional skin, but it is limited by the intrinsic growth capacity. The authors conducted a study of autologous concentrated growth factor (CGF) to promote skin regeneration by increasing skin thickness and area during tissue expansion. METHODS: A single-center randomized controlled trial was conducted from 2016 to 2019. Participants undergoing skin expansion received either CGF or saline by means of intradermal injection on the expanded skin (0.02 mL/cm 2 ), for a total of three treatments at 4-week intervals. The primary endpoint was the expanded skin thickness at 12 weeks, which was measured by ultrasound. The secondary endpoints included skin thickness at 4 and 8 weeks and surface area, expansion index, and skin texture score of the expanded skin at 12 weeks. Safety assessments, for infection symptoms and nodule formation, were assessed at 24 weeks. RESULTS: In total, 26 patients were enrolled and assigned to the CGF or control group. Compared with the control group, the CGF group had significantly increased skin thickness at 8 (control, 1.1 ± 0.1 mm; CGF, 1.4 ± 0.1 mm; -0.6 to 0.0 mm; P = 0.047) and 12 weeks (control, 1.0 ± 0.1 mm; CGF, 1.3 ± 0.1 mm; -0.6 to 0.0 mm; P = 0.047). Compared with the baseline thickness (control, 1.6 ± 0.1 mm; CGF, 1.5 ± 0.1 mm; -0.3 to 0.5 mm; P = 0.987), skin thickness was sustained in the CGF group at 8 weeks after treatment (-0.1 to 0.3 mm; P = 0.711) but decreased in the control group (0.3 to 0.7 mm; P < 0.001). At 12 weeks, the CGF group showed greater increases in surface area (control, 77.7 ± 18.5 cm 2 ; CGF, 135.0 ± 15.7 cm 2 ; 7.2 cm 2 to 107.4 cm 2 ; P = 0.027) and expansion index (control, 0.9 ± 0.1; CGF, 1.4 ± 0.2; 0.0 to 0.8; P = 0.030) than the control group. In addition, CGF-treated skin showed an improvement in texture [CGF: grade 3, n = 2 (15.8%), grade 2, n = 4 (30.7%); control: grade 3, n = 0 (0.0%), grade 2, n = 3 (23.0%)]. No severe adverse events occurred. CONCLUSION: CGF treatment increases skin thickness and area during tissue expansion, and represents a safe and effective strategy for managing skin expansion. CLINICAL RELEVANCE STATEMENT: The findings of this study indicate that it is practically feasible to improve skin regeneration by applying autologous platelet concentrate therapy for skin expansion management. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Venous thromboembolism risk following temporary immobilisation after injury: evaluation of the Aberdeen VTE risk tool.

BACKGROUND: Temporary lower limb immobilisation following injury is a risk factor for symptomatic venous thromboembolism (VTE). Pharmacological thromboprophylaxis can mitigate this risk but it is unclear which patients benefit from this intervention. The Aberdeen VTE risk tool was developed to tailor thromboprophylaxis decisions in these patients and this evaluation aimed to describe its performance in clinical practice. Secondarily, diagnostic metrics were compared with other risk assessment methods (RAMs). METHODS: A prospective cohort service evaluation was conducted. Adult patients (≥16 years) managed with lower limb immobilisation for injury who were evaluated with the Aberdeen VTE risk tool prior to discharge from the ED were identified contemporaneously between February 2014 and December 2020. Electronic patient records were scrutinised up to 3 months after removal of immobilisation for the development of symptomatic VTE or sudden death due to pulmonary embolism (PE). Other RAMs, including the Thrombosis Risk Prediction for Patients with cast immobilisation (TRiP(cast)) and Plymouth scores, were assimilated retrospectively and diagnostic performance compared. RESULTS: Of 1763 patients (mean age 46 (SD 18) years, 51% women), 15 (0.85%, 95% CI 0.52% to 1.40%) suffered a symptomatic VTE or death due to PE. The Aberdeen VTE tool identified 1053 (59.7%) patients for thromboprophylaxis with a sensitivity of 80.0% (95% CI 54.8% to 93.0%) and specificity of 40.4% (95% CI 38.1% to 42.6%) for the primary outcome. In 1695 patients, fewer were identified as high risk by the TRiP(cast) (33.3%) and Plymouth (24.4%) scores, but with greater specificity, 67.0% and 75.6%, respectively, than dichotomous RAMs, including the Aberdeen VTE tool. CONCLUSION: Routine use of the Aberdeen VTE tool in our population resulted in an incidence of symptomatic VTE of less than 1%. Ordinal RAMs, such as the TRiP(cast) score, may more accurately reflect VTE risk and permit more individually tailored thromboprophylaxis decisions but prospective comparison is needed.

Comparing log file to measurement-based patient-specific quality assurance.

Recent technological advances have allowed the possibility of performing patient-specific quality assurance (QA) without time-intensive measurements. The objectives of this study are to: (1) compare how well the log file-based Mobius QA system agrees with measurement-based QA methods (ArcCHECK and portal dosimetry, PD) in passing and failing plans, and; (2) evaluate their error sensitivities. To these ends, ten phantom plans and 100 patient plans were measured with ArcCHECK and PD on VitalBeam, while log files were sent to Mobius for dose recalculation. Gamma evaluation was performed using criteria 3%/2 mm, per TG218 recommendations, and non-inferiority of the Mobius recalculation was determined with statistical testing. Ten random plans were edited to include systematic errors, then subjected to QA. Receiver operating characteristic curves were constructed to compare error sensitivities across the QA systems, and clinical significance of the errors was determined by recalculating dose to patients. We found no significant difference between Mobius, ArcCHECK, and PD in passing plans at the TG218 action limit. Mobius showed good sensitivity to collimator and gantry errors but not MLC bank shift errors, but could flag discrepancies in treatment delivery. Systematic errors were clinically significant only at large magnitudes; such unacceptable plans did not pass QA checks at the TG218 tolerance limit. Our results show that Mobius is not inferior to existing measurement-based QA systems, and can supplement existing QA practice by detecting real-time delivery discrepancies. However, it is still important to maintain rigorous routine machine QA to ensure reliability of machine log files.