Who Are the Anatomic Outliers Undergoing Total Knee Arthroplasty? A Computed Tomography-Based Analysis of the Hip-Knee-Ankle Axis Across 1,352 Preoperative Computed Tomographies Using a Deep Learning and Computer Vision-Based Pipeline.

BACKGROUND: Dissatisfaction after total knee arthroplasty (TKA) ranges from 15 to 30%. While patient selection may be partially responsible, morphological and reconstructive challenges may be determinants. Preoperative computed tomography (CT) scans for TKA planning allow us to evaluate the hip-knee-ankle axis and establish a baseline phenotypic distribution across anatomic parameters. The purpose of this cross-sectional analysis was to establish the distributions of 27 parameters in a pre-TKA cohort and perform threshold analysis to identify anatomic outliers. METHODS: There were 1,352 pre-TKA CTs that were processed. A 2-step deep learning pipeline of classification and segmentation models identified landmark images and then generated contour representations. We used an open-source computer vision library to compute measurements for 27 anatomic metrics along the hip-knee axis. Normative distribution plots were established, and thresholds for the 15th percentile at both extremes were calculated. Metrics falling outside the central 70th percentile were considered outlier indices. A threshold analysis of outlier indices against the proportion of the cohort was performed. RESULTS: Significant variation exists in pre-TKA anatomy across 27 normally distributed metrics. Threshold analysis revealed a sigmoid function with a critical point at 9 outlier indices, representing 31.2% of subjects as anatomic outliers. Metrics with the greatest variation related to deformity (tibiofemoral angle, medial proximal tibial angle, lateral distal femoral angle), bony size (tibial width, anteroposterior femoral size, femoral head size, medial femoral condyle size), intraoperative landmarks (posterior tibial slope, transepicondylar and posterior condylar axes), and neglected rotational considerations (acetabular and femoral version, femoral torsion). CONCLUSIONS: In the largest non-industry database of pre-TKA CTs using a fully automated 3-stage deep learning and computer vision-based pipeline, marked anatomic variation exists. In the pursuit of understanding the dissatisfaction rate after TKA, acknowledging that 31% of patients represent anatomic outliers may help us better achieve anatomically personalized TKA, with or without adjunctive technology.

[Evaluation of a structured e-learning-based approach to CT anatomy of the paranasal sinuses for medical students : A pilot study]. / Evaluation eines strukturierten E­Learning-basierten Ansatzes zur Vermittlung der CT-Anatomie der Nasennebenhöhlen bei Medizinstudierenden : Eine Pilotstudie.

BACKGROUND: Computed tomography (CT) anatomy is not an integral part of undergraduate medical training in many countries. Radiology seems to be well suited for new online-based teaching methods. OBJECTIVE: The aim of this study was to evaluate whether e­learning is appropriate for introducing complex learning contents such as sinus CT anatomy to novices and to assess whether identification of relevant anatomical variants in sinus CT scans by medical students can be improved with a sinus CT checklist. MATERIALS AND METHODS: Medical students were asked to assess sinus CT scans for anatomical variants before and after implementation of the CLOSE mnemonic (cribriform plate, lamina papyracea, Onodi cell, sphenoid sinus pneumatization, and [anterior] ethmoidal artery). Sinus CT anatomy and the CLOSE mnemonic were introduced by e­learning. The rate of correctly identified variants and the results of the individual CLOSE items were recorded. A questionnaire was distributed for subjective evaluation of the usefulness of the checklist and e­learning. RESULTS: Ten students took part in this pilot study. The rate of correctly identified variants improved significantly, from 33.3 to 61.1%. The analysis of the individual CLOSE items showed a significant improvement for C, S, and E. The subjective evaluation of the CLOSE mnemonic and e­learning was very positive. CONCLUSION: E­learning was able to transfer complex learning contents in previously non-trained medical students and was evaluated as an appropriate introduction to the topics. Structured assessment of paranasal sinus CT scans using the CLOSE criteria can significantly improve the recognition of anatomical variants.

[Objective and subjective assessment of a structured approach to computed tomography scans of the paranasal sinuses]. / Objektive und subjektive Bewertung eines strukturierten Vorgehens zur Beurteilung von Computertomographien der Nasennebenhöhlen.

BACKGROUND: Sound knowledge of individual anatomy is essential in sinus surgery to prevent potentially serious complications. For the paranasal sinuses, computed tomography (CT) is the imaging technique of choice to preoperatively analyze individual anatomy and the extent of disease. OBJECTIVE: The purpose of this study was to evaluate the usefulness of a CT checklist to identify relevant anatomic variants in CTs of the paranasal sinuses. MATERIALS AND METHODS: Junior and senior otolaryngology residents were asked to assess sinus CT scans for anatomic variants before and after implementation of the CLOSE mnemonic (cribriform plate, lamina papyracea, Onodi cell, sphenoid sinus pneumatization, and [anterior] ethmoidal artery). The rate of correctly identified variants was calculated. A questionnaire was distributed for subjective evaluation of the usefulness of the checklist. RESULTS: Six junior and six senior residents were included in the study. The rate of correctly identified anatomic variations significantly improved from 23.1 to 50.9% and 24 to 39.8%, respectively, after implementation of the CLOSE mnemonic. The subjective evaluation of the CLOSE criteria showed very positive results. CONCLUSION: The structured approach to sinus CT scans using CT criteria can improve identification of critical anatomic variants in CT scans of the paranasal sinuses and is rated highly positively by residents in training.

Preoperative CT for postoperative radiotherapy planning in breast cancer.

INTRODUCTION: The exact location of the original tumor should be known for a targeted increase in the dose to the tumor bed after breast cancer surgery. Therefore, at our site, we perform CT examinations of patients in the radiation position before breast cancer surgery. METHODS: Preoperative native CT scans were performed in the patients in the planning position for radiotherapy; these data were fused with standard planning CT for boost irradiation. We evaluated whether the tumor was accurately identifiable in preoperative CT scans. We also contoured one irradiation volume in the standard planning CT scans and the other in the fusion CT scans with preoperative examination, and compared these volumes. RESULTS: Out of the total number of 554 patients, we were able to identify the exact location of the breast tumor in 463 cases (83.6 %). In a group of 50 randomly selected patients, the clinical target volume for the boost dose to the postlumpectomy cavity was changed in 20 patients (40%) - decreased in 9 cases (18%) and increased in 11 cases (22%). CONCLUSION: As shown by the results of our study, preoperative CT in the planning position can be used in patients with confirmed breast cancer. This method allows us to more accurately locate the tumor bed and thus more accurately draw the target volume for boost irradiation. We confirmed that preoperative CT had an impact on the size of the target volume.

Masculinizing Genital Surgery: An Imaging Primer for the Radiologist.

OBJECTIVE. Masculinizing genital surgeries for transgender individuals are currently performed at only a select few centers; however, radiologists in any geographic region may be confronted with imaging studies of transgender patients. The imaging findings of internal and external genital anatomy of a transgender patient may differ substantially from the imaging findings of a cisgender patient. This article provides the surgical and anatomic basis to allow appropriate interpretation of preoperative and postoperative imaging findings. We also expand on the most common complications and associated imaging findings. CONCLUSION. As these procedures become more commonplace, radiologists will have a growing role in the care of transgender patients and will be faced with new anatomic variants and differential diagnoses. Familiarity with these anatomic variations and postoperative complications is crucial for the radiologist to provide an accurate and useful report.

Accuracy of preoperative T and N staging in colon cancer--a national population-based study.

AIM: To select patients for neoadjuvant therapy in colon cancer, there is a need to improve pre-therapeutic locoregional staging. There are now data showing that the TN stage can be adequately assessed by preoperative CT in dedicated centres. In Sweden the use of preoperative CT of the abdomen for staging of the primary tumour is increasing. The aim of this study was to determine to what extent the preoperatively reported radiological TN stage correlates with the histopathological TN stage in an entire population. METHOD: Data were collected on the preoperative cTN stage according to the radiologist and postoperative pTN stage according to the pathologist on all patients operated on for colon cancer in Sweden 2007-2010. The correlation between cTN stage and pTN stage was calculated using kappa statistics. RESULTS: T stage was compared in 4373 patients with cT and pT stage. The correlation coefficient was 0.44, indicating fair agreement. The cN and pN correlation coefficient was 0.28, indicating a slight correlation. There was no difference in correlation related to age, gender, tumour location, body mass index or emergent vs elective surgery. A slight difference was seen between different geographical regions. CONCLUSION: Preoperative CT in an unselected population does not result in an accurate cTN staging as previously reported from dedicated centres. To achieve adequate preoperative cTN staging nationally, the education of radiologists and optimization of the radiological method will be necessary.

Automating Linear and Angular Measurements for the Hip and Knee After Computed Tomography: Validation of a Three-Stage Deep Learning and Computer Vision-Based Pipeline for Pathoanatomic Assessment.

Background: Variability in the bony morphology of pathologic hips/knees is a challenge in automating preoperative computed tomography (CT) scan measurements. With the increasing prevalence of CT for advanced preoperative planning, processing this data represents a critical bottleneck in presurgical planning, research, and development. The purpose of this study was to demonstrate a reproducible and scalable methodology for analyzing CT-based anatomy to process hip and knee anatomy for perioperative planning and execution. Methods: One hundred patients with preoperative CT scans undergoing total knee arthroplasty for osteoarthritis were processed. A two-step deep learning pipeline of classification and segmentation models was developed that identifies landmark images and then generates contour representations. We utilized an open-source computer vision library to compute measurements. Classification models were assessed by accuracy, precision, and recall. Segmentation models were evaluated using dice and mean Intersection over Union (IOU) metrics. Contour measurements were compared against manual measurements to validate posterior condylar axis angle, sulcus angle, trochlear groove-tibial tuberosity distance, acetabular anteversion, and femoral version. Results: Classifiers identified landmark images with accuracy of 0.91 and 0.88 for hip and knee models, respectively. Segmentation models demonstrated mean IOU scores above 0.95 with the highest dice coefficient of 0.957 [0.954-0.961] (UNet3+) and the highest mean IOU of 0.965 [0.961-0.969] (Attention U-Net). There were no statistically significant differences for the measurements taken automatically vs manually (P > 0.05). Average time for the pipeline to preprocess (48.65 +/- 4.41 sec), classify/retrieve landmark images (8.36 +/- 3.40 sec), segment images (<1 sec), and obtain measurements was 2.58 (+/- 1.92) minutes. Conclusions: A fully automated three-stage deep learning and computer vision-based pipeline of classification and segmentation models accurately localized, segmented, and measured landmark hip and knee images for patients undergoing total knee arthroplasty. Incorporation of clinical parameters, like patient-reported outcome measures and instability risk, will be important considerations alongside anatomic parameters.

Endovascular navigation in patients: vessel-based registration of electromagnetic tracking to preoperative images.

Electromagnetic tracking of instruments combined with preoperative images can supplement fluoroscopy for guiding endovascular aortic repair (EVAR). The aim of this study was to evaluate the in-vivo accuracy of a vessel-based registration algorithm for matching electromagnetically tracked positions of an endovascular instrument to preoperative computed tomography angiography. Five patients undergoing elective EVAR were included, and a clinically available semi-automatic 3D-3D registration algorithm, based on similarity measures computed over the entire image, was used for reference. Accuracy was reported as target registration error (TRE) evaluated in manually selected anatomic landmarks on bony structures, placed close to the volume-of-interest. The median TRE was 8.2 mm (range: 7.1 mm to 16.1 mm) for the vessel-based registration algorithm, compared to 2.2 mm (range: 1.8 mm to 3.7 mm) for the reference algorithm. This illustrates that registration based on intraoperative electromagnetic tracking is feasible, but the accuracy must be improved before clinical use.

Radiation exposure in navigated techniques for AIS: is there a difference between pre-operative CT and intraoperative CT?

PURPOSE: Utilization of navigation improves pedicle screw accuracy in adolescent idiopathic scoliosis (AIS). Our center switched from intraoperative CT (ICT) to an optical navigation system that utilizes pre-operative CT (PCT). We aim to evaluate the radiation dose and operative time for low-dose ICT compared to standard and low-dose PCT used for optical navigation in AIS patients undergoing posterior spinal fusion. METHODS: A single-center matched-control cohort study of 38 patients was conducted. Nineteen patients underwent ICT navigation (O-arm) and were matched by sex, age, and weight to 19 patients who underwent PCT for use with an optical-guided navigation (7D, Seaspine). A total of 418 levels were instrumented and reviewed. PCT was either a standard dose (N = 7) or a low dose (N = 12). The mean volume CT dose index, dose-length product, overall effective dose (ED), ED per level instrumented, and operative time per level were compared. RESULTS: ED per level instrumented was 0.061 ± 0.029 mSv in low-dose PCT and 0.14 ± 0.05 mSv in low-dose ICT (p < 0.0001). ED per level instrumented was significantly higher in standard PCT (1.46 ± 0.39 vs. 0.14 ± 0.03 mSv; p < 0.0001). Mean operative time per level was 31 ± 7 min for ICT and 33 ± 3 min for PCT (p = 0.628). CONCLUSION: Low-dose PCT resulted in 0.70 mSv exposure per case and 31 min per level, standard-dose was 16.95 mSv, while ICT resulted in 1.34-1.62 mSv and a similar operative time. Use of a standard-dose PCT involves radiation exposure about 9 times higher than ICT and 23 times higher than low-dose PCT per level instrumented. LEVEL OF EVIDENCE: Level III.

Preoperative CT-based radiomics combined with tumour spread through air spaces can accurately predict early recurrence of stage I lung adenocarcinoma: a multicentre retrospective cohort study.

OBJECTIVE: To develop and validate a prediction model for early recurrence of stage I lung adenocarcinoma (LUAD) that combines radiomics features based on preoperative CT with tumour spread through air spaces (STAS). MATERIALS AND METHODS: The most recent preoperative thin-section chest CT scans and postoperative pathological haematoxylin and eosin-stained sections were retrospectively collected from patients with a postoperative pathological diagnosis of stage I LUAD. Regions of interest were manually segmented, and radiomics features were extracted from the tumour and peritumoral regions extended by 3 voxel units, 6 voxel units, and 12 voxel units, and 2D and 3D deep learning image features were extracted by convolutional neural networks. Then, the RAdiomics Integrated with STAS model (RAISm) was constructed. The performance of RAISm was then evaluated in a development cohort and validation cohort. RESULTS: A total of 226 patients from two medical centres from January 2015 to December 2018 were retrospectively included as the development cohort for the model and were randomly split into a training set (72.6%, n = 164) and a test set (27.4%, n = 62). From June 2019 to December 2019, 51 patients were included in the validation cohort. RAISm had excellent discrimination in predicting the early recurrence of stage I LUAD in the training cohort (AUC = 0.847, 95% CI 0.762-0.932) and validation cohort (AUC = 0.817, 95% CI 0.625-1.000). RAISm outperformed single modality signatures and other combinations of signatures in terms of discrimination and clinical net benefits. CONCLUSION: We pioneered combining preoperative CT-based radiomics with STAS to predict stage I LUAD recurrence postoperatively and confirmed the superior effect of the model in validation cohorts, showing its potential to assist in postoperative treatment strategies.

Retrospective cohort study of the impact of faecoliths on the natural history of acute appendicitis.

BACKGROUND: Despite acute appendicitis is one of the most common surgical emergencies, its aetiology remains incompletely understood. AIM: This study aimed to assess the rate at which faecoliths were present in acute appendicitis treated with appendicectomy and whether their presence was associated with complicated appendicitis. METHODS: All adult patients who underwent appendicectomy for acute appendicitis in a 2 years period (January 2018 and December 2019) at a single institution were retrospectively reviewed. The presence of a faecolith was identified by at least one of three methods: pre-operative CT scan, intraoperative identification, or histopathology report. Patients were grouped according to the presence or absence of a faecolith and demographics, type of appendicitis and surgical outcomes analysed. Complicated appendicitis was defined as appendicitis with perforation, gangrene and/or periappendicular abscess formation. RESULTS: A total of 1035 appendicectomies were performed with acute appendicitis confirmed in 860 (83%), of which 314 (37%) were classified as complicated appendicitis. Three hundred thirty-nine (35%) of the appendicitis cases had faecoliths (complicated 165/314 cases; 53%; uncomplicated 128/546; 23%, p < 0.001). The presence of a faecolith was associated with higher complications and a subsequent longer post-operative stay. CONCLUSION: The rigorous methodology of this study has demonstrated a higher rate of faecolith presence in acute appendicitis than previously documented. It reinforces the association of faecoliths with a complicated disease course and the importance in prioritising emergency surgery and postoperative monitoring for complications.

Preoperative prognostic prediction for stage I lung adenocarcinomas: Impact of the computed tomography features associated with the new histological grading system.

Objectives: This study aimed to identify the computed tomography (CT) features associated with the new International Association for the Study of Lung Cancer (IASLC) three-tiered grading system to improve the preoperative prediction of disease-free survival of stage I lung adenocarcinoma patients. Methods: The study included 379 patients. Ordinal logistic regression analysis was used to identify the independent predictors of IASLC grades. The first multivariate Cox regression model (Model 1) was based on the significant factors from the univariate analysis. The second multivariate model (Model 2) excluded the histologic grade and based only on preoperative factors. Results: Larger consolidation tumor ratio (OR=2.15, P<.001), whole tumor size (OR=1.74, P=.002), and higher CT value (OR=3.77, P=.001) were independent predictors of higher IASLC grade. Sixty patients experienced recurrences after 70.4 months of follow-up. Model 1 consisted of age (HR:1.05, P=.003), clinical T stage (HR:2.32, P<.001), histologic grade (HR:4.31, P<.001), and burrs sign (HR:5.96, P<.001). Model 2 consisted of age (HR,1.04; P=.015), clinical T stage (HR:2.49, P<.001), consolidation tumor ratio (HR:2.49, P=.016), whole tumor size (HR:2.81, P=.022), and the burrs sign (HR:4.55, P=.002). Model 1 had the best prognostic predictive performance, followed by Model 2, clinical T stage, and histologic grade. Conclusion: CTR (cut-off values of <25% and ≥75%) and whole tumor size (cut-off value of 17 mm) could stratify patients into different prognosis and be used as preoperative surrogates for the IASLC grading system. Integrating these CT features with clinical T staging can improve the preoperative prognostic prediction for stage I lung adenocarcinoma patients.

Tips and pitfalls to improve accuracy and reduce radiation exposure in intraoperative CT navigation for pediatric scoliosis: a systematic review.

BACKGROUND CONTEXT: An increasing number of medical centers are adopting an intraoperative computed tomography (iCT) navigation system (iCT-Navi) to provide three-dimensional navigation for pediatric scoliosis surgery. While iCT-Navi has been reported to provide higher pedicle screw (PS) insertion accuracy, it may also result in higher radiation exposure to the patient. What innovations and studies have been introduced to reduce radiation exposure and further improve PS insertion? PURPOSE: Evaluate the level of evidence and quality of papers while categorizing the tips and pitfalls regarding pediatric scoliosis surgery using iCT-Navi. Compare iCT-Navi with other methods, including preoperative CT navigation. STUDY DESIGN: Systematic review. PATIENT SAMPLE: Articles on pediatric scoliosis surgery with iCT-Navi published through to June 2022. OUTCOME MEASURES: PS perforation rate and patient intraoperative radiation dose. METHODS: Following PRISMA guidelines, the Cochrane Library, Google Scholar, and PubMed databases were searched for articles satisfying the criteria of iCT-Navi use and pediatric scoliosis surgery. The level of evidence and quality of the articles meeting the criteria were evaluated according to the guidelines of the North American Spine Society and American Academy of Orthopedic Surgeons, respectively. The articles were also categorized by theme and summarized in terms of PS insertion accuracy and intraoperative radiation dose. The origins and characteristics of five major classification methods of PS perforation grade were summarized as well. RESULTS: The literature search identified 811 studies, of which 20 papers were included in this review. Overall, 513 pediatric scoliosis patients (381 idiopathic, 44 neuromuscular, 39 neurofibromatosis type 1, 28 congenital, 14 syndromic, seven other) were evaluated for PS perforations among 6,209 iCT-Navi insertions. We found that 232 (3.7%) screws were judged as major perforations (G2 or G3), 55 (0.9%) screws were judged as dangerous deviations (G3), and seven (0.1%) screws were removed. There were no reports of neurovascular injury caused by PSs. The risk factors for PS perforation included more than six vertebrae distance from the reference frame, more than nine consecutive insertions, upper thoracic level, thinner pedicle, upper instrumented vertebra proximity, short stature, and female. The accuracy of PS insertion did not remarkably decrease when the radiation dose was reduced to 1/5 or 1/10 by altering the iCT-Navi protocol. CONCLUSIONS: iCT-Navi has the potential to reduce PS perforation rates compared with other methods. The use of low-dose radiation protocols may not significantly affect PS perforation rates. Although several risk factors for PS perforation and measures to reduce radiation dose have been reported, the current evidence is limited by a lack of consistency in classifying PS perforation and evaluating patient radiation dose among studies. The standardization of several outcome definitions is recommended in this rapidly developing field.

Puncture frequency predicts pneumothorax in preoperative computed tomography-guided lung nodule localization for video-assisted thoracoscopic surgery.

BACKGROUND: Iatrogenic pneumothorax is the most frequent complication in preoperative CT-guided localization (POCTGL) of lung nodules. We aimed to determine the predictive factors of iatrogenic pneumothorax. METHODS: We retrospectively analyzed data of consecutive POCTGL procedures in patients who received video-assisted thoracoscopic surgery (VATS) at our hospital between May 2015 and October 2019. All of our patients utilized laser angle guide assembly to aid in the localization procedures. RESULTS: In 610 consecutive POCTGL procedures, 40 (6.6%) patients developed iatrogenic pneumothorax, and complications occurred in 8.5%. Univariate analyses revealed that puncture frequency, male gender, puncture depth, left decubitus position, and nodule near fissure were factors associated with pneumothorax, while multivariate analysis showed that only male gender (odds ratio 3.58, p = 0.012) and puncture frequency (odds ratio 2.39/time, p = 0.0004) determined development of pneumothorax. Further collective analysis on puncture frequency revealed that tumor in a difficult zone (1.33 ± 0.71 vs. 1.19 ± 0.45, p = 0.002), especially adjacent to the mediastinum (1.41 ± 0.75 vs. 1.21 ± 0.52, p = 0.002), angle difference of plan-to-practice (r = 0.209, p = < 0.001), depth to skin (r = 0.152, p < 0.001), and depth to pleura (r = 0.164, p < 0.001) were factors related to increased puncture frequency in univariate analyses. Only angle difference of plan-to-practice was associated in multivariate analysis (odds ratio: 1.158, p = 0.008). CONCLUSIONS: Puncture frequency was the key factor in the development of iatrogenic pneumothorax from POCTGL. Other associated factors, especially angle difference, may have affected the puncture frequency and subsequently have some influence on the incidence of iatrogenic pneumothorax.

Importance of CT Scan in Predicting the Outcomes of Tibial Plateau Fractures: A Retrospective Study of 216 Patients over 10 Years' Time.

BACKGROUND: The primary aim of this retrospective study was to assess the postoperative clinical, functional, and radiographic outcomes of patients with closed tibial plateau fractures (TPFs) surgically treated with proximal tibial locking compression plate (LCP) system with a focus on the use of preoperative CT scan. METHODS: Two hundred and sixteen patients with TPFs who underwent surgical treatment in our department between January 2010 and December 2019 were enrolled in this study. Ninety-five patients of 216 (44.0%) had preoperative CT examination in addition to plain radiographs to better evaluate the pattern of fracture and displacement of fragments. Clinical and functional outcomes were assessed using VAS, SF-36, Knee Society Score (KSS) and WOMAC score. Radiographic outcomes were evaluated according to the Kellgreen- Lawrence classification of the pre- and postoperative grades of valgus knee, articular displacement and gonarthrosis. RESULTS: Patients with preoperative CT showed better clinical results than the X-ray group for the VAS, KSS, WOMAC and SF-36 score. Moreover, we found that the X-ray group had worse results than the CT group in the rate of varus-valgus alignment and step-off worsening, while the posterior tibial slope showed no significant changes between the two groups at the final follow-up. Finally, the group of patients who received preoperative CT scans displayed a better immediate postoperative reduction and less long-term arthritis. CONCLUSION: CT has proved to be a good examination in preoperative planning of TPFs: it can influence postoperative results thanks to an improvement in the surgical approach, a better evaluation of the morphology of fracture lines and the involvement of the Luo's three columns in axial CT scans.

Correlation of Pre-operative Temporal Bone CT Scan Findings with Intraoperative Findings in Chronic Otitis Media: Squamous Type.

To correlate the pre-operative Temporal Bone High Resolution Computer Tomography (HRCT) Scan findings with intraoperative findings in Chronic Otitis Media-Squamous type. This prospective, correlative, observational study was done at Department of Otorhinolaryngology and Head and Neck Surgery, Tribhuvan University Teaching Hospital, Kathmandu. 156 patients underwent mastoid surgery under General Anaesthesia from October 2017 to November 2018. Ethical committee approval taken from the institutional review committee. Informed consent regarding the study was taken prior to surgery. The peroperative findings were correlated with preoperative HRCT findings. Cohen's kappa coefficient (k-value) was used to estimate the degree of correlation. Statistical analysis was done using SPSS version 25. Total 156 patients between 8 and 70 years of age were enrolled in the study. Presence of cholesteatoma/granulation on HRCT scan was found with 100% sensitivity with k-value of 0.569 denoting fair agreement. Regarding ossicular status, malleus showed maximum k-value of 0.525 with sensitivity of 81.3% followed by stapes and incus with k-value of 0.308 and 0.380 and sensitivity of 68.3% and 70.2% respectively. Sinus plate status showed perfect radiosurgical agreement with k-value of 1.0 and sensitivity and specificity of 100%. Bony facial canal demonstrated slight agreement with k-value of 0.506 and sensitivity of 45.8%. Dural plate status showed fair agreement with k-value of 0.503 and sensitivity of 38.9%. For Lateral Semicircular Canal (LSCC) erosion, we found very good agreement with k-value of 0.893 with sensitivity of 90.9%. Preoperative HRCT scan temporal bone correlates well for the detection of disease presence and shows good radiosurgical agreement for sinus plate erosion, LSCC erosion but fair agreement for dural plate erosion and malleus erosion. Plain HRCT scan with 3-D reconstruction is a poor predictor of bony facial canal, incus and stapes erosion.

Potential benefits, unintended consequences, and future roles of artificial intelligence in orthopaedic surgery research : a call to emphasize data quality and indications.

Artificial intelligence and machine-learning analytics have gained extensive popularity in recent years due to their clinically relevant applications. A wide range of proof-of-concept studies have demonstrated the ability of these analyses to personalize risk prediction, detect implant specifics from imaging, and monitor and assess patient movement and recovery. Though these applications are exciting and could potentially influence practice, it is imperative to understand when these analyses are indicated and where the data are derived from, prior to investing resources and confidence into the results and conclusions. In this article, we review the current benefits and potential limitations of machine-learning for the orthopaedic surgeon with a specific emphasis on data quality.

Study of the prognostic factor of the colon perforation case with the pan-peritonitis that needed emergency surgery: a single-center observational study.

AIM: We divided patients treated with emergency surgery for pan-peritonitis caused by colon perforation into the survival group and the death group based on outcome at postoperative day 30 and examined the prognostic factors for colon perforation. METHODS: The prognostic factors for colon perforation in 76 consecutive patients who underwent emergency surgery at Kansai Medical University Hospital (Hirakata, Japan) from April 2011 to March 2017 were investigated based on outcome at postoperative day 30. RESULTS: The average age of the 76 patients (41 men/35 women) was 73 years, and the causative disease of colon perforation was malignant/benign in 18/58 cases, with ileocecal perforation site in 8 cases, ascending colon in 6, transverse colon in 2, descending colon in 4, sigmoid colon in 49, and rectum in 7. All patients received laparotomy with irrigation drainage, and 9 patients (11.8%) were dead at 30 days. Upon comparing the 67 survivors with the 9 dead patients, we recognized a significant difference on preoperative spread of ascites on computed tomography (CT) (P = 0.002) in univariate analysis and on acute disseminated intravascular coagulation (DIC) score (odds ratio 2.289; 95% confidence interval, 1.188-4.410; P = 0.013) in multivariate analysis. CONCLUSION: In our hospital, the preoperative acute DIC score was found to be a prognostic factor for colon perforation accompanied by pan-peritonitis. Appropriate evaluation of the spread of ascites on the preoperative CT might also help predict patient prognosis.

Computed tomography-guided dye localization for deeply situated pulmonary nodules in thoracoscopic surgery.

BACKGROUND: Increased lung cancer screening of asymptomatic adults using low-dose computed tomography (CT) with high-resolution imaging modalities has increased the identification of small and deeply situated pulmonary nodules. This study aimed to evaluate the role of preoperative patient blue vital (PBV) dye localization for an undiagnosed nodule deeply situated in the lung parenchyma followed by minimally invasive lung resection. METHODS: From July 2013 to December 2016, 27 consecutive patients (16 women, median age: 62 years) with small undiagnosed pulmonary nodules at a depth of more than 30 mm underwent preoperative CT-guided PBV dye localization followed by thoracoscopic diagnostic resection of the nodule at National Taiwan University Hospital. The clinical characteristics were collected retrospectively to evaluate the efficacy and safety of the procedure. RESULTS: The median size of pulmonary nodule in preoperative CT images was 11 mm with a median depth of 31.6 mm (range, 30.0-48.6 mm). Of the 27 nodules, 8 were pure ground-glass nodules, 3 were pure solid nodules, and 16 were partially solid nodules. The diagnostic yield of CT-guided dye localization following diagnostic wedge resection was 100%. The final pathological diagnoses were: primary adenocarcinoma of the lung (n=20), adenocarcinoma in situ (n=1), and benign nodules (n=6). Only asymptomatic complications were noted after localization, and the median hospital stay was 3 days [interquartile range (IQR), 3-4 days]. All of 21 patients were cancer-free after a median follow-up of 39.0 months (IQR, 29.5-50.0 months). CONCLUSIONS: This study indicated that preoperative, percutaneous CT-guided PBV dye localization for undiagnosed nodules at a depth of more than 30 mm could be a safe and feasible procedure. Furthermore, it was considerably advantageous for preserving the lung parenchyma, especially for benign nodules.