Category: Statistics

Childs Nerv Syst. 2021 Aug 17. doi: 10.1007/s00381-021-05326-1. Online ahead of print.

ABSTRACT

PURPOSE: To review the use of different valve types in infants with hydrocephalus, in doing so, determining whether an optimal valve choice exists for this patient cohort.

METHODS: We conducted (1) a literature review for all studies describing valve types used (programmable vs. non-programmable, valve size, pressure) in infants (≤ 2 years) with hydrocephalus, (2) a review of data from the pivotal BASICS trial for infant patients and (3) a separate, institutional cohort study from Alder Hey Children’s Hospital NHS Foundation Trust. The primary outcome was any revision not due to infection.

RESULTS: The search identified 19 studies that were included in the review. Most did not identify a superior valve choice between programmable and non-programmable, small compared to ultra-small, and differential pressure compared to flow-regulating valves. Five studies investigated a single-valve type without a comparator group. The BASICS data identified 391 infants, with no statistically significant difference between gravitational and programmable subgroups. The institutional data from our tertiary referral centre did not reveal any significant difference in failure rate between valve subtypes.

CONCLUSION: Our review highlights the challenges of valve selection in infant hydrocephalus, reiterating that the concept of an optimal valve choice in this group remains a controversial one. While the infant-hydrocephalic population is at high risk of valve failure, heterogeneity and a lack of direct comparison between valves in the literature limit our ability to draw meaningful conclusions. Data that does exist suggests at present that there is no difference in non-infective failure rate are increasing in number, with the British valve subtypes in infant hydrocephalus, supported by both the randomised trial and institutional data in this study.

PMID:34402954 | DOI:10.1007/s00381-021-05326-1

Pediatr Radiol. 2021 Aug 17. doi: 10.1007/s00247-021-05128-2. Online ahead of print.

ABSTRACT

BACKGROUND: Since coronavirus disease 2019 (COVID-19) was declared a worldwide pandemic in March 2020, many authors have noted the collateral damage on non-COVID-19-related illnesses. These indirect effects of the pandemic have resulted in people presenting later and with more severe stages of disease, even if their diagnoses are not directly related to SARS-CoV-2, the virus that causes COVID-19.

OBJECTIVE: We studied these indirect effects of COVID-19 on the imaging workup and outcomes for pediatric patients at our center who had acute appendicitis during the pandemic.

MATERIALS AND METHODS: We performed a retrospective review of cases in children ≤18 years who were evaluated for acute appendicitis during the same period, March 1 to May 31, in both 2019 and 2020. We compared demographic and clinical data as well as surgical and pathological findings, and we graded imaging findings according to severity. Differences in patient outcomes were assessed using the Wilcoxon rank sum test and the Pearson chi-square test.

RESULTS: The total number of pediatric patients evaluated with imaging for acute appendicitis dropped by 43% between 2019 and 2020 (298 vs. 169), but the total number of children treated remained similar (59 vs. 51). There was proportionate use of US and CT in each timeframe but a higher percentage of positive imaging findings in 2020 (50/169, 29.6% vs. 56/298, 18.7% in 2019, P=0.04). There were more imaging examinations with features of complicated appendicitis among positive cases (9/51, 18% vs. 5/59, 8% in 2019, P=0.08) and more pathologically proven perforated cases during the pandemic (14/51, 27% vs. 6/59, 10% in 2019, P=0.11), although these results did not reach statistical significance. There were no changes in surgical management, vital signs, laboratory values, length of stay or complication rates.

CONCLUSION: There was a large drop in the number of pediatric patients imaged for acute appendicitis during the acute phase of the COVID-19 pandemic despite similar numbers of patients treated. The utilization trends of US vs. CT remained stable between time periods. The differences in imaging findings and perforation rates were less pronounced compared to other published studies.

PMID:34402958 | DOI:10.1007/s00247-021-05128-2

Arch Orthop Trauma Surg. 2021 Aug 17. doi: 10.1007/s00402-021-04120-7. Online ahead of print.

ABSTRACT

INTRODUCTION: Complex orthopaedic procedures, such as iliosacral screw (ISS) fixations, can take advantage of surgical navigation technology to achieve accurate results. Although the impact of surgical navigation on outcomes has been studied, no studies to date have quantified how the design of the targeting display used for navigation affects ISS targeting performance. However, it is known in other contexts that how task information is displayed can have significant effects on both accuracy and time required to perform motor tasks, and that this can be different among users with different experience levels. This study aimed to investigate which visualization techniques helped experienced surgeons and inexperienced users most efficiently and accurately align a surgical tool to a target axis.

METHODS: We recruited 21 participants and conducted a user study to investigate five proposed 2D visualizations (bullseye, rotated bullseye, target-fixed, tool-fixed in translation, and tool-fixed in translation and rotation) with varying representations of the ISS targets and tool, and one 3D visualization. We measured the targeting accuracy achieved by each participant, as well as the time required to perform the task using each of the visualizations.

RESULTS: We found that all 2D visualizations had equivalent translational and rotational errors, with mean translational errors below 0.9 mm and rotational errors below 1.1[Formula: see text]. The 3D visualization had statistically greater mean translational and rotational errors (4.29 mm and 5.47[Formula: see text], p < 0.001) across all users. We also found that the 2D bullseye view allowed users to complete the simulated task most efficiently (mean 30.2 s; 95% CI 26.4-35.7 s), even when combined with other visualizations.

CONCLUSIONS: Our results show that 2D bullseye views helped both experienced orthopaedic trauma surgeons and inexperienced users target iliosacral screws accurately and efficiently. These findings could inform the design of visualizations for use in a surgical navigation system for screw insertions for both training and surgical practice.

PMID:34402930 | DOI:10.1007/s00402-021-04120-7

Abdom Radiol (NY). 2021 Aug 17. doi: 10.1007/s00261-021-03224-3. Online ahead of print.

ABSTRACT

PURPOSE: To compare the diagnostic performance of ¹⁸F-fluorodeoxyglucose-PET/MRI and MRI in the diagnosis of pelvic recurrence of rectal cancer.

METHODS: All PET/MRIs of patients in the follow-up of rectal cancer performed between 2011 and 2018 at our institution were retrospectively reviewed. Recurrence was confirmed/excluded either by histopathology or imaging follow-up (> 4 months). Four groups of readers (groups 1/2: one radiologist each, groups 3/4: one radiologist/one nuclear medicine physician) independently interpreted MRI and PET/MRI. The likelihood of recurrence was scored on a 5-point-scale. Inter-reader agreement, sensitivity, specificity, PPV/NPV and accuracy were assessed. ROC curve analyses were performed.

RESULTS: Fourty-one PET/MRIs of 40 patients (mean 61 years ± 10.9; 11 women, 29 men) were included. Sensitivity of PET/MRI in detecting recurrence was 94%, specificity 88%, PPV/NPV 97% and 78%, accuracy 93%. Sensitivity of MRI was 88%, specificity 75%, PPV/NPV 94% and 60%, accuracy 85%. ROC curve analyses showed an AUC of 0.97 for PET/MRI and 0.92 for MRI, but the difference was not statistically significant (p = 0.116). On MRI more cases were scored as equivocal (12% versus 5%). Inter-reader agreement was substantial for PET/MRI and MRI (0.723 and 0.656, respectively).

CONCLUSION: ¹⁸F-FDG-PET/MRI and MRI are accurate in the diagnosis of locally recurrent rectal cancer. Sensitivity, specificity, PPV, NPV and accuracy are comparable for both modalities, but PET/MRI increases readers’ confidence levels and reduces the number of equivocal cases.

PMID:34402948 | DOI:10.1007/s00261-021-03224-3

Clin Res Cardiol. 2021 Aug 17. doi: 10.1007/s00392-021-01920-0. Online ahead of print.

ABSTRACT

Heart transplantation (HTx) is a valid therapeutic option for end-stage heart failure secondary to cardiac sarcoidosis (CS) or giant-cell myocarditis (GCM). However, post-HTx outcomes in patients with inflammatory cardiomyopathy (ICM) have been poorly investigated. We searched PubMed, Scopus, Science Citation Index, EMBASE, and Google Scholar, screened the gray literature, and contacted experts in the field. We included studies comparing post-HTx survival, acute cellular rejection, and disease recurrence in patients with and without ICM. Data were synthesized by a random-effects meta-analysis. We screened 11,933 articles, of which 14 were considered eligible. In a pooled analysis, post-HTx survival was higher in CS than non-CS patients after 1 year (risk ratio [RR] 0.88, 95% confidence interval [CI] 0.60-1.17; I² = 0%) and 5 years (RR 0.72, 95% CI 0.52-0.91; I² = 0%), but statistically significant only after 5 years. During the first-year post-HTx, the risk of acute cellular rejection was similar for patients with and without CS, but after 5 years, it was lower in those with CS (RR 0.38, 95% CI 0.03-0.72; I² = 0%). No difference in post-HTx survival was observed between patients with and without GCM after 1 year (RR 1.16, 95% CI 0.05-2.28; I² = 0%) or 5 years (RR 0.98, 95% CI 0.42-1.54; I² = 0%). During post-HTx follow-up, recurrence of CS and GCM occurred in 5% and 8% of patients, respectively. Post-HTx outcomes in patients with CS and GCM are comparable with cardiac recipients with other heart failure etiologies. Patients with ICM should not be disqualified from HTx.

PMID:34402927 | DOI:10.1007/s00392-021-01920-0

Arch Orthop Trauma Surg. 2021 Aug 17. doi: 10.1007/s00402-021-04100-x. Online ahead of print.

ABSTRACT

INTRODUCTION: High tibial osteotomy (HTO) is a valid and joint preserving surgical technique to treat medial degenerative osteoarthritis (OA) in young and active patients. A recent study shows that patients’ expectations of osteotomy around the knee are high, but OA progression and potential conversion to a total knee arthroplasty (TKA) were underestimated. The aim of this study was to investigate surgeons’ expectations of HTO and to compare the results to the patients’ expectations and actual outcomes reported in the literature.

METHODS: 461 surgeons were questioned online using the ‘Hospital for Special Surgery Knee Surgery Expectations Survey (HFSS-KSES)’ and a ten-item non-validated questionnaire to investigate the expectations of HTO. Two subgroups were formed to investigate differences regarding the surgeons’ experience. Statistical analysis was performed using IBM SPSS Statistics.

RESULTS: Surgeons’ expectations of HTO were rated between very and little important with pain reduction being the most important item on the HFSS-KSES. Furthermore, ‘improving the ability to walk’, ‘to perform daily activities’, ‘having confidence in the knee’, and ‘avoiding future degeneration’ were rated of high importance. An important difference regarding the experience was the lower expectations on delay/prevention of TKA of less-experienced surgeons.

CONCLUSION: Surgeons’ expectations of HTO are high but nevertheless different to the patients’ expectations reported in the literature. Also, expectations for the delay/prevention of TKA differed regarding the experience of surgeons. While pain reduction represents one of the most important items for surgeons and patients, the expected outcome regarding the delay/prevention of a TKA and returning to sports differs to the patients’ expectations and to the actual outcome reported in the literature. This should be considered when performing the preoperative informed consent.

PMID:34402929 | DOI:10.1007/s00402-021-04100-x

J Crohns Colitis. 2021 Aug 17:jjab133. doi: 10.1093/ecco-jcc/jjab133. Online ahead of print.

ABSTRACT

BACKGROUND AND AIMS: Report results from VISIBLE 2, a randomised, double-blind, placebo-controlled phase 3 trial evaluating a new subcutaneous [SC] vedolizumab formulation as maintenance treatment in adults with moderately to severely active Crohn’s disease [CD].

METHODS: Following open-label vedolizumab 300 mg intravenous induction therapy at Weeks 0 and 2, Week 6 clinical responders (≥70-point decrease in CD Activity Index [CDAI] score from baseline) were randomised 2:1 to receive double-blind maintenance vedolizumab 108 mg SC or placebo every 2 weeks until Week 50. Assessments at Week 52 included clinical remission [primary endpoint; CDAI≤150], enhanced clinical response [≥100-point decrease in CDAI from baseline], corticosteroid-free clinical remission among patients using a corticosteroid at baseline, clinical remission in anti-tumour necrosis factor [anti-TNF]-naïve patients, and safety.

RESULTS: Following vedolizumab intravenous induction, 275 patients were randomised to vedolizumab SC and 135 to placebo maintenance. At Week 52, 48.0% of patients receiving vedolizumab SC versus 34.3% receiving placebo were in clinical remission [p=0.008]. Enhanced clinical response at Week 52 was achieved by 52.0% versus 44.8% of patients receiving vedolizumab SC versus placebo, respectively [p=0.167]. At Week 52, 45.3% and 18.2% of patients receiving vedolizumab SC and placebo, respectively, were in corticosteroid-free clinical remission, and 48.6% of anti-TNF-naïve patients receiving vedolizumab SC and 42.9% receiving placebo were in clinical remission. Injection site reaction was the only new safety finding observed for vedolizumab SC [2.9%].

CONCLUSIONS: Vedolizumab SC is an effective and safe maintenance therapy in patients with CD who responded to two infusions of vedolizumab intravenous induction therapy.

PMID:34402887 | DOI:10.1093/ecco-jcc/jjab133

J Orofac Orthop. 2021 Aug 17. doi: 10.1007/s00056-021-00340-z. Online ahead of print.

ABSTRACT

PURPOSE: The goal of this study was to compare the shear bond strength (SBS) and failure modes of three different adhesive resins following the use of two different dental curing light units.

METHODS: A total of 160 human premolars were randomly divided into four groups (N = 40 for each): group 1, Transbond™ XT (3M Unitek, Monrovia, CA, USA) adhesive paste; group 2, Heliosit Orthodontic paste with no primer; group 3, Maxcem Elite (Kerr, Orange, CA, USA) self-adhesive resin with prior etching; group 4, Maxcem Elite self-adhesive resin with no etching. Each group was further divided into 2 subgroups: half (named “a”) were cured with VALO LED (Ultradent Products, South Jordan, UT, USA), and the other half (named “b”) with the Elipar LED unit (3M Unitek LED, Monrovia, CA, USA). The brackets were submitted to SBS testing 24 h after bonding. Adhesive Remnant Index (ARI) scores and bonding time were also measured. Two-way analysis of variance (ANOVA) and Kruskal-Wallis tests were used for statistical analysis.

RESULTS: No significant differences in SBS were observed when comparing the two different LED devices within the same bonding material. The mean SBS of group 1 was significantly higher compared to groups 2, 3, and 4 (p < 0.001). Mean SBS values of groups 2 and 3 were significantly higher than that of group 4 (p < 0.001). ARI scores were significantly different in groups 4a and 4b compared to the other groups (p < 0.05). Group 4a showed significantly lower bonding time/tooth compared to the other groups except to groups 3a and 4b (p < 0.001).

CONCLUSIONS: Decreasing curing time using high-power LED device did not significantly affect SBS. However, the composite type did affect SBS.

PMID:34402921 | DOI:10.1007/s00056-021-00340-z

Brief Bioinform. 2021 Aug 17:bbab326. doi: 10.1093/bib/bbab326. Online ahead of print.

ABSTRACT

Genotype imputation is a statistical method for estimating missing genotypes from a denser haplotype reference panel. Existing methods usually performed well on common variants, but they may not be ideal for low-frequency and rare variants. Previous studies showed that the population similarity between study and reference panels is one of the key factors influencing the imputation accuracy. Here, we developed an imputation reference panel reconstruction method (RefRGim) using convolutional neural networks (CNNs), which can generate a study-specified reference panel for each input data based on the genetic similarity of individuals from current study and references. The CNNs were pretrained with single nucleotide polymorphism data from the 1000 Genomes Project. Our evaluations showed that genotype imputation with RefRGim can achieve higher accuracies than original reference panel, especially for low-frequency and rare variants. RefRGim will serve as an efficient reference panel reconstruction method for genotype imputation. RefRGim is freely available via GitHub: https://github.com/shishuo16/RefRGim.

PMID:34402866 | DOI:10.1093/bib/bbab326

Arch Pathol Lab Med. 2021 Aug 17. doi: 10.5858/arpa.2020-0686-OA. Online ahead of print.

ABSTRACT

CONTEXT.—: Intraoperative consultation-frozen section diagnosis (FSD)-determines tumor pathology and guides the optimal surgical management of ovarian neoplasms intraoperatively.

OBJECTIVE.—: To evaluate the diagnostic accuracy of the FSD and analyze the discrepancy between the FSD and final diagnosis.

DESIGN.—: This is a retrospective study of 618 ovarian neoplasm FSDs from 2009 to 2018 at a tertiary health care center. The discrepant cases were reviewed and reevaluated by gynecologic and general surgical pathologists. The outcomes of interest were performing unnecessary procedure, returning for a second surgery, and 30-day postoperative mortality.

RESULTS.—: The sensitivity and the positive predictive value of the FSD were lower in borderline tumors than in benign and malignant epithelial ovarian tumors. Major and minor discrepancies were identified in 5.3% (33 of 618) and 12.3% of (76 of 618) cases, respectively. A root cause analysis of the major discrepant cases showed that sampling error accounted for 43% (14 of 33). The discrepancy distributions of gynecologic and general surgical pathologists were statistically similar in the overall cohort (P = .65). The overall κ for diagnostic agreement among gynecologic pathologists, general surgical pathologists, and final diagnosis was 0.18 (0.10-0.26, P < .001), implying only a slight overall agreement. Of the major discrepant cases, only 3 had a clinical implication. One overdiagnosed patient underwent unnecessary procedure and 2 underdiagnosed patients were recommended to return for a second surgery. No patient had 30-day postoperative mortality.

CONCLUSIONS.—: Frozen section diagnosis remains a definitive diagnostic tool in ovarian neoplasms and plays a crucial role in guiding intraoperative surgical management.

PMID:34402886 | DOI:10.5858/arpa.2020-0686-OA