Serial Computed Tomography Scans Research Articles

Solitary lung adenocarcinoma: follow-up CT, pathological-molecular characteristics, and surgical prognosis for different morphological classifications

ObjectiveTo investigate the dynamic changes during follow-up computed tomography (CT), histological subtypes, gene mutation status, and surgical prognosis for different morphological presentations of solitary lung adenocarcinomas (SLADC).Materials and methodsThis retrospective study compared dynamic tumor changes and volume doubling time (VDT) in 228 patients with SLADC (morphological types I–IV) who had intermittent growth during follow-ups. The correlation between the morphological classification and histological subtypes, gene mutation status, and surgical prognosis was evaluated.ResultsAmong the 228 patients, 66 (28.9%) were classified as type I, 123 (53.9%) as type II, 16 (7%) as type III, and 23 (10.1%) as type IV. Type I had the shortest VDT (254 days), followed by types IV (381 days) and III (501 days), and then type II (993 days) (p < 0.05 each). Type I had a greater proportion of solid/micropapillary-predominant pattern than type II, and the lepidic-predominant pattern was more common in type II and III than in type I (p < 0.05 each). Furthermore, type II and IV SLADCs were correlated with positive epidermal growth factor receptor mutation (p < 0.05 each). Lastly, the Kaplan–Meier curves showed that the disease-free survival was longest for patients with type II tumors, followed by those with type III and IV tumors, and then those with type I tumors (p < 0.001 each).ConclusionA good understanding of the natural progression and pathological-molecular characteristics of different morphological SLADC types can help make accurate diagnoses, develop individual treatment strategies, and predict patient outcomes.Critical relevance statementA good understanding of the natural progression and pathological-molecular characteristics of different morphological solitary lung adenocarcinoma types can help make accurate diagnoses, develop individual treatment strategies, and predict patient outcomes.Key points• Type I–IV solitary lung adenocarcinomas exhibit varying natural progression on serial CT scans.• Morphological classification of solitary lung adenocarcinomas predicts histological subtype, gene status, and surgical prognosis.• This classification of solitary lung adenocarcinomas may help improve diagnostic, therapeutic, and prognosticating abilities.Graphical

Pericardial Hematoma Following Coronary Angiography

ntroduction: Pericardial hematoma is defined as an accumulation of blood in the pericardial space, located in close proximity to the myocardium and deep to the fibrous pericardial sac, which encloses the heart. Case Description: We present a rare case of pericardial hematoma following percutaneous coronary intervention in an individual presenting with stenotic vein graft following symptoms of a myocardial infarction. Initial computed tomography (CT) scan demonstrated hematoma in the pericardial space. This finding was managed conservatively and hematoma was deemed stable on serial CT scans. Discussion: In this urgent situation, CT imaging proves valuable due to its speed, convenience, and accuracy in visualizing the target area from different perspectives. Although patients may appear stable initially after a perforation, a pericardial hematoma can rapidly spread, leading to unstable blood flow that requires prompt intervention and long-term monitoring.

Catheter Tract Hemorrhages and Intracerebral Hemorrhage Outcomes in the Clot Lysis: Evaluating Accelerated Resolution of Intraventricular Hemorrhage Trial.

Factors associated with external ventricular catheter tract hemorrhage (CTH) are well studied; whether CTH adversely influence outcomes after intracerebral hemorrhage (sICH), however, is poorly understood. We therefore sought to evaluate the association between CTH and sICH outcomes. We performed a post hoc analysis of the Clot Lysis: Evaluating Accelerated Resolution of Intraventricular Hemorrhage trial. The exposure was CTH and evaluated on serial computed tomography scans between admission and randomization (approximately 72 hours). The primary outcomes were a composite of death or major disability (modified Rankin Score >3) and mortality alone, both assessed at 6 months. Secondary outcomes were functional outcomes at 30 days, permanent cerebrospinal fluid (CSF) shunt placement, any infection, and ventriculitis. We performed logistic regression adjusted for demographics, comorbidities, sICH characteristics, and treatment assignment, for all analyses. Of the 500 patients included, the mean age was 59 (SD, ±11) years and 222 (44%) were female. CTH occurred in 112 (22.4%) patients and was more common in minority patients, those on prior antiplatelet therapy, and patients who had more than 1 external ventricular drain placed. The end of treatment intraventricular hemorrhage volume was higher among patients with CTH (11.7 vs 7.9 mL, P = .01), but there were no differences in other sICH characteristics or the total duration of external ventricular drain. In multivariable regression models, CTH was not associated with death or major disability (odds ratio, 0.7; 95% CI: 0.4-1.2) or death alone (odds ratio, 0.8; 95% CI, 0.5-1.4). There were no relationships between CTH and secondary outcomes including 30-day functional outcomes, permanent CSF shunt placement, any infection, or ventriculitis. Among patients with sICH and large intraventricular hemorrhage, CTH was not associated with poor sICH outcomes, permanent CSF shunt placement, or infections. A more detailed cognitive evaluation is needed to inform about the role of CTH in sICH prognosis.

Chemical pancreatectomy in non-human primates ablates the acini and ducts and enhances beta-cell function

Chronic pancreatitis is a debilitating disease affecting millions worldwide. These patients suffer from bouts of severe pain that are minimally relieved by pain medications and may necessitate major surgeries with high morbidity and mortality. Previously, we demonstrated that “chemical pancreatectomy,” a pancreatic intraductal infusion of dilute acetic acid solution, ablated the exocrine pancreas while preserving the endocrine pancreas. Notably, chemical pancreatectomy resolved chronic inflammation, alleviated allodynia in the cerulein pancreatitis model, and improved glucose homeostasis. Herein, we extensively tested the feasibility of a chemical pancreatectomy in NHPs and validated our previously published pilot study. We did serial computed tomography (CT) scans of the abdomen and pelvis, analyzed dorsal root ganglia, measured serum enzymes, and performed histological and ultrastructural assessments and pancreatic endocrine function assays. Based on serial CT scans, chemical pancreatectomy led to the loss of pancreatic volume. Immunohistochemistry and transmission electron microscopy demonstrated exocrine pancreatic ablation with endocrine islet preservation. Importantly, chemical pancreatectomy did not increase pro-nociceptive markers in harvested dorsal root ganglia. Also, chemical pancreatectomy improved insulin secretion to supranormal levels in vivo and in vitro. Thus, this study may provide a foundation for translating this procedure to patients with chronic pancreatitis or other conditions requiring a pancreatectomy.

Advanced non-small-cell lung cancer treated with first-line pembrolizumab plus chemotherapy: tumor response dynamics as a marker for survival.

The study investigated tumor burden dynamics on computed tomography (CT) scans in patients with advanced non-small-cell lung cancer (NSCLC) during first-line pembrolizumab plus chemotherapy, to provide imaging markers for overall survival (OS). The study included 133 patients treated with first-line pembrolizumab plus platinum-doublet chemotherapy. Serial CT scans during therapy were assessed for tumor burden dynamics during therapy, which were studied for the association with OS. There were 67 responders, with overall response rate of 50%. The tumor burden change at the best overall response ranged from - 100.0% to + 132.1% (median of - 30%). Higher response rates were associated with younger age (p < 0.001) and higher programmed cell death-1 (PD-L1) expression levels (p = 0.01). Eighty-three patients (62%) showed tumor burden below the baseline burden throughout therapy. Using an 8-week landmark analysis, OS was longer in patients with tumor burden below the baseline burden in the first 8weeks than in those who experienced ≥ 0% increase (median OS: 26.8 vs. 7.6months, hazard ratio (HR): 0.36, p < 0.001). Tumor burden remained below their baseline throughout therapy was associated with significantly reduced hazards of death (HR: 0.72, p = 0.03) in the extended Cox models, after adjusting for other clinical variables. Pseudoprogression was noted in only one patient (0.8%). Tumor burden staying below the baseline burden throughout the therapy was predictive of prolonged overall survival in patients with advanced NSCLC treated with first-line pembrolizumab plus chemotherapy, and may be used as a practical marker for therapeutic decisions in this widely used combination regimen. The analysis of tumor burden dynamics on serial CT scans in reference to the baseline burden can provide an additional objective guide for treatment decision making in patients treated with first-line pembrolizumab plus chemotherapy for their advanced NSCLC. • Tumor burden remaining below baseline burden during therapy predicted longer survival during first-line pembrolizumab plus chemotherapy. • Pseudoprogression was noted in 0.8%, demonstrating the rarity of the phenomenon. • Tumor burden dynamics may serve as an objective marker for treatment benefit to guide treatment decisions during first-line pembrolizumab plus chemotherapy.

Diagnosis and treatment of a novel Mycobacterium haemophilum associated pneumonia in an African pygmy hedgehog (Atelerix albiventris)

AbstractAn unknown age (at least 1.5‐year old), male, entire African pygmy hedgehog (Atelerix albiventris) was presented for decreased appetite, lethargy and laboured breathing. Pulmonary radiographic lesions consistent with pneumonia were noted in serial computed tomography scans. The hedgehog initially responded well to treatment with azithromycin and orbifloxacin for several months, but its health declined upon discontinuation of treatment. After continued decline despite resumed antibiotic therapy, the patient was humanely euthanised. A postmortem examination was performed, and histologic examination identified severe granulomatous bronchointerstitial pneumonia with intralesional acid‐fast staining bacteria. Samples from the lung and liver were positive for Mycobacterium haemophilum by PCR and further DNA sequencing. This report describes the clinical presentation, diagnosis, treatment and outcome of a pulmonary infection caused by M. haemophilum in a hedgehog.

Magnetic Resonance Imaging in the Management of Significantly Displaced Adolescent Posterior Sternoclavicular Joint Injuries.

Computed tomography (CT) scans are the standard imaging modality for the diagnosis and treatment guide for adolescent posterior sternoclavicular joint (SCJ) injuries. However, the medial clavicular physis is not visualized and it is not possible to differentiate between a true SCJ dislocation and a physeal injury (PI). An magnetic resonance imaging (MRI) scan can visualize the bone and the physis. We treated a series of patients with adolescent posterior SCJ injuries diagnosed on CT scan. Patients underwent an MRI scan to differentiate between a true SCJ dislocation and a PI and to further differentiate between a PI with or without residual medial end clavicular bone contact. Patients with a true SCJ dislocation and a PI with no contact underwent an open reduction and fixation. Patients with a PI with contact were treated nonoperatively with repeat CT scans at 1 and 3 months. At final follow-up SCJ clinical function was assessed using Quick-DASH, Rockwood, modified Constant, and single assessment numeric evaluation (SANE) scores. Thirteen patients (2 female and 11 male) with an average age of 14.9 years (12 to 17) were included in the study. Twelve patients were available at final follow-up (mean 50mo, 26 to 84). One patient had a true SCJ dislocation and 3 had an off-ended PI and were treated with an open reduction and fixation. Eight patients had a PI with residual bone contact and were treated nonoperatively. For these patients serial CT scans showed that the position was maintained, with a serial increase in callus formation and bone remodeling. The average follow-up was 42.9 months (24 to 62). At final follow-up the mean Quick-disabilities of the arm, shoulder and hand (DASH) was 0.4 (0 to 2.3), Rockwood was 15, modified Constant was 98.8 (89 to 100) and SANE was 99.5% (95 to 100). In this case series of significantly displaced adolescent posterior SCJ injuries MRI scans allowed identification of true SCJ dislocations and off-ended PIs, which were successfully treated by open reduction, and PIs with residual physeal contact which were successfully treated nonoperatively. Level IV-case series.

Evaluation of Volumetric Lymph Node Measurements in Cutaneous T-Cell Lymphoma Patients Enrolled in the Mavoric Trial: An Interim Analysis

Lymph node assessment is an important component of staging, classification, and treatment response assessment in cutaneous T-cell lymphoma (CTCL). Although a biopsy is the only definitive way to assess nodal involvement, radiologic evaluation is commonly used in practice given its practicality. Current radiologic criteria are adapted from guidelines for lymphomas with primarily nodal involvement and have not been validated in CTCL patients. These criteria are limited by linear measurements which fail to accurately capture small and/or asymmetric nodal involvement in CTCL and may lead to flawed estimations of the overall disease burden. Furthermore, unidimensional and bidimensional measurements are subject to significant inter- and intra-observer variability. More accurate methods of lymph node evaluation are needed to improve risk stratification and treatment response assessment in CTCL. Recent advances in digital imaging techniques have made it possible to obtain volumetric tumor measurements. This technique has shown promise as a more accurate imaging biomarker than unidimensional measurements in several solid cancer types, offering improved sensitivity for changes in tumor burden during treatment. Volumetric lymph node measurements have been shown to be superior to unidimensional measurements in distinguishing between benign and malignant lymph nodes in systemic lymphoma, however volumetric measurements have never been studied in CTCL. The aim of this study was to assess the utility of volumetric lymph node measurements in CTCL using this novel imaging technique. We analyzed imaging and clinical data from the mogamulizumab versus vorinostat in previously treated cutaneous T-cell lymphoma (MAVORIC) trial which included 372 CTCL patients randomized to receive either mogalizumab or vorinostat. The majority of patients randomized to vorinostat crossed over to mogalizumab due to disease progression or intolerance. As part of the trial, patients underwent computed tomography (CT) scans at baseline and regular follow-up intervals to assess for lymph node response to treatment. In our study, target lymph nodes in serial CT scans were measured by a team of radiologists using a response assessment system built on open-source software known as the Weasis imaging platform. Semi-automated segmentation algorithms were used to quantify unidimensional and bidimensional measurements as well as lymph node volumes. Our preliminary data suggests that there is a correlation between unidimensional, bidimensional, and volumetric lymph node measurements. For the first time, we validate volumetric lymph node measurement as a viable method of lymph node assessment in CTCL. This implicates lymph node volume as an alternative metric for lymph node assessment in CTCL that has the potential to improve the accuracy of current nodal assessment criteria. Additional research is underway to determine whether volumetric lymph node measurements are superior to uni- and bidimensional measurements in assessing treatment response and predicting clinical outcomes in CTCL.

High-Density Lipoprotein and Long-Term Incidence and Progression of Aortic Valve Calcification: The Multi-Ethnic Study of Atherosclerosis.

Aortic valve calcification (AVC) shares pathological features with atherosclerosis. Lipoprotein components have been detected in aortic valve tissue, including HDL (high-density lipoprotein). HDL measures have inverse associations with cardiovascular disease, but relationships with long-term AVC progression are unclear. We investigated associations of HDL cholesterol, HDL-particle number and size, apoC3-defined HDL subtypes, and, secondarily, CETP (cholesteryl ester transfer protein) mass and activity, with long-term incidence and progression of AVC. We used linear mixed-effects models to evaluate the associations of baseline HDL indices with AVC. AVC was quantified by Agatston scoring of up to 3 serial computed tomography scans over a median of 8.9 (maximum 11.2) years of follow-up in the Multi-Ethnic Study of Atherosclerosis (n=6784). After adjustment, higher concentrations of HDL-C (high-density lipoprotein cholesterol), HDL-P (HDL particles), large HDL-P, and apoC3-lacking HDL-C were significantly associated with lower incidence/progression of AVC. Neither small or medium HDL-P nor apoC3-containing HDL-C was significantly associated with AVC incidence/progression. When included together, a significant association was observed only for HDL-C, but not for HDL-P. Secondary analyses showed an inverse relationship between CETP mass, but not activity, and AVC incidence/progression. In exploratory assessments, inverse associations for HDL-C, HDL-P, large HDL-P, and apoC3-lacking HDL with AVC incidence/progression were more pronounced for older, male, and White participants. ApoC3-containing HDL-C only showed a positive association with AVC in these subgroups. In a multiethnic population, HDL-C, HDL-P, large HDL-P, and apoC3-lacking HDL-C were inversely associated with long-term incidence and progression of AVC. Further investigation of HDL composition and mechanisms could be useful in understanding pathways that slow AVC.

Is It Possible to Replace Conventional Radiography (CR) with a Dose Neutral Computed Tomography (CT) of the Cervical Spine in Emergency Radiology-An Experimental Cadaver Study.

The purpose of this experimental study on recently deceased human cadavers was to investigate whether (I) the radiation exposure of the cervical spine CT can be reduced comparable to a dose level of conventional radiography (CR); and (II) whether and which human body parameters can be predictive for higher dose reduction potential (in this context). Materials and Methods: Seventy serial CT scans of the cervical spine of 10 human cadavers undergoing postmortem virtual autopsy were taken using stepwise decreasing upper limits of the tube current (300 mAs, 150 mAs, 110 mAs, 80 mAs, 60 mAs, 40 mAs, and 20 mAs) at 120 kVp. An additional scan acquired at a fixed tube current of 300 mAs served as a reference. Images were reconstructed with filtered back projection and the upper (C1-4) and lower (C4-7) cervical spine were evaluated by three blinded readers for image quality, regarding diagnostic value and resolution of anatomical structures according to a semiquantitative three-point-scale. Dose values and individual physical parameters were recorded. The relationship of diagnostic IQ, dose reduction level, and patients’ physical parameters were investigated. The high-contrast resolution of the applied CT protocols was tested in an additional phantom study. Results: The IQ of the upper cervical spine was diagnostic at 1.69 ± 0.58 mGy (CTDI) corresponding to 0.20 ± 0.07 mSv (effective dose) in all cadavers. IQ of the lower cervical spine was diagnostic at 4.77 ± 1.86 mGy corresponding to 0.560 ± 0.21 mSv (effective dose) in seven cadavers and at 2.60 ± 0.93 mGy corresponding to 0.31 ± 0.11 mSv in four cadavers. Significant correlation was detected for BMI (0.8366; p = 0.002548) and the anteroposterior (a.p.) chest diameter (0.8363; p = 0.002566), shoulder positioning (0.79799; p = 0.00995), and radiation exposure. Conclusions: Conventional radiography can be replaced with a nearly dose-neutral CT scan of the cervical spine.

Rapidly progressive interstitial lung disease in patients with anti-melanoma differentiation-associated gene 5-positive dermatomyositis: serial changes on HRCT.

Anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibodies in patients with dermatomyositis are associated with rapidly progressive interstitial lung disease (RP-ILD). Computed tomography (CT) plays a central role in the diagnosis of RP-ILD and may help characterize the temporal changes. We report five anti-MDA5-positive dermatomyositis patients with serial CT scans spanning their acute RP-ILD disease course. Our case series highlights the variable imaging pattern that can manifest in this setting, including diffuse alveolar damage and nonspecific interstitial pneumonia patterns. Three patients in our series died within 4months of their disease onset, whereas the other two patients survived. The serial CT changes in anti-MDA5 disease are dynamic and variable; therefore, it is imperative to maintain a broad differential when faced with these HRCT patterns to improve the diagnosis and management of this underrecognized entity.

Longitudinal Changes in Bone Mineral Measurements Inside and Outside Radiation Fields Used for Cervical Cancer Treatment

PurposeWe compared the magnitude of changes in bone mineral density (BMD), within and outside the radiation field, among women who received pelvic radiation therapy (RT) with or without chemotherapy for cervical cancer. Methods and MaterialsIn this secondary analysis of a prospective study, we analyzed serial computed tomography scans and dual-energy x-ray absorptiometry scans from 78 patients who received definitive RT or chemoradiation therapy (CRT) for cervical cancer at a single institution from 2008 to 2015. BMD values at L1, L2, L3, and L4 were measured. We compared changes in BMD within the radiation field (ie, at L4) with those outside the field (ie, at L1). Linear mixed models were also used to examine the effect of RT on changes in BMD over time and covariate adjustment. ResultsThe median age of the 78 patients was 45.5 years (range, 23-88 years); all received RT and 76 (97%) received concurrent CRT. Treatment was associated with significant declines in BMD in all 4 lumbar vertebral bodies over time (P < .05), with nadir at 3 months for L4 and at 1 year for L1. Pairwise comparisons at 3 months and 2 years after treatment indicated that BMD in L4 (within the RT field) had improved (P = .037), but BMD in L1 (outside the RT field) was no different at 3 months and 2 years. ConclusionsSignificant BMD declines were observed in all lumbar vertebral bodies immediately after RT. However, in-field vertebral bodies reached nadir BMD earlier than those located outside the RT field. Our results suggest that treatment and patient-related factors other than RT may contribute to declines in BMD after treatment for cervical cancer. Routine bone density screening and post-RT therapy with hormones may be beneficial for selected patients who receive CRT for cervical cancer.

A155 ASEPTIC ABSCESS SYNDROME IN INFLAMMATORY BOWEL DISEASE: A CASE REPORT

BackgroundAseptic abscess syndrome (AAS) is a rare extraintestinal manifestation of inflammatory bowel disease (IBD) and it is characterized by the formation of sterile collections of neutrophils in various organs. Misdiagnosis frequently leads to unnecessary surgical procedures and prolonged courses of antibiotics. There are only 61 reportable cases of AAS in the international literature and 2 cases in Canada. This case and the associated literature review highlight the diagnostic considerations, treatment options and disease course of this rare disease.AimsTo describe a case of AAS in IBD.MethodsCase report and review of the literature.ResultsA 24-year-old male with a history of ulcerative pancolitis (UC) initially presented with a 3-week history of malaise, abdominal pain, and fevers with a computed tomography (CT) scan showing multiple splenic abscesses. Over the next year, he had multiple readmissions for recurrent sepsis from culture negative multi-focal abscesses. Serial CT scans revealed new abscesses in the liver, scrotum, and lungs with interval progression in size. Unsuccessful attempts to isolate a culprit organism which included serological markers and cultures from blood, bronchial washings, aspirate from abscesses, and surgical tissue. All samples demonstrated frank pus with suppurative granulomatous inflammation. The patient was trialed on various courses of antibiotics without improvement. Therefore, a decision was made to treat for AAS given his IBD history. Antibiotics were discontinued and prednisone was initiated with rapid improvement in symptoms and biochemistry. In the three years following, he was transitioned to a combination of infliximab and azathioprine. He had rapid resolution of his abscesses on serial CT scans following steroid and anti-TNF therapy. Currently, he is no longer on steroids and his CRP has normalized with no recurrence of his symptoms.ConclusionsAAS has often been associated with IBD, particularly Crohn’s disease and more rarely in UC. Case series have shown that AAS is not strongly associated with IBD activity as only 55% of cases have concomitant IBD flare and abscess formation. The syndrome continues to pose a diagnostic conundrum among specialists as there is no established diagnostic criteria and thus AAS remains a diagnosis of exclusion. This has led many patients to suffer from AAS for prolonged periods and receive unnecessary investigations and treatments. Steroids remain the gold standard for initial induction of remission. However, the ideal regimen for maintenance therapy is still evolving and case reports have described the effects of immunotherapy and biologics on AAS. AAS has a substantial impact on quality of life and is very responsive to therapy; this case report reminds the clinician that AAS should be considered in patients with IBD presenting with multifocal abscesses unresponsive to antimicrobials. Serial CT scan (coronal view) of abdomen demonstrating multiple hepatic abscesses (blue arrows)Funding AgenciesNone

Usage of image registration and three-dimensional visualization tools on serial computed tomography for the analysis of patients with traumatic intraparenchymal hemorrhages

The aim of this study was to apply registration and three-dimensional (3D) display tools to assess the evolution of intraparenchymal hemorrhage (IPH) in patients with traumatic brain injury (TBI). We identified 109 TBI patients who had two computed tomography (CT) scans within 4 days retrospectively. The IPH was manually outlined. The registration was performed in 39 lesions from 29 patients with lesion volume < 1.5 cm on both baseline and follow-up CT. The center of mass (COM) of each lesion was calculated, and the distance between baseline and follow-up CT was used to evaluate the registration effect. The mean distances of COM before registration in the XYZ, XY, and YZ coordinates were 20.5 ± 10.2 mm, 17.8 ± 9.4 mm, and 15.9 ± 9.4 mm, respectively, which decreased significantly (p < 0.001) to 7.9 ± 4.9, 7.8 ± 5.0, and 6.1 ± 4.1 mm after registration. A 3D short video displaying the rendering view of all lesions in 34 randomly selected patients from baseline and follow-up scans were presented side-by-side for comparison. The detection rate of new IPH lesions increased in 3D videos (100%) as compared with axial CT slices (78.6–92.9%). A very high interrater agreement (k = 0.856) on perceiving IPH lesion progression upon viewing 3D video was noted, and the absolute volume increase was significantly higher (p < 0.001) for progressive lesions (median 7.36 cc) over non-progressive lesions (median 0.01 cc). Compared to patients with spontaneous hemorrhagic stroke, evaluation of multiple small traumatic hemorrhages in TBI is more challenging. The applied image analysis and visualization methods may provide helpful tools for comparing changes between serial CT scans.

Automated Assessment of Renal Calculi in Serial Computed Tomography Scans.

An automated pipeline is developed for the serial assessment of renal calculi using computed tomography (CT) scans obtained at multiple time points. This retrospective study included 722 scans from 330 patients chosen from 8544 asymptomatic patients who underwent two or more CTC (CT colonography) or non-enhanced abdominal CT scans between 2004 and 2016 at a single medical center. A pre-trained deep learning (DL) model was used to segment the kidneys and the calculi on the CT scans at each time point. Based on the output of the DL, 330 patients were identified as having a stone candidate on at least one time point. Then, for every patient in this group, the kidneys from different time points were registered to each other, and the calculi present at multiple time points were matched to each other using proximity on the registered scans. The automated pipeline was validated by having a blinded radiologist assess the changes manually. New graph-based metrics are introduced in order to evaluate the performance of our pipeline. Our method shows high fidelity in tracking changes in renal calculi over multiple time points.

Incidental Pulmonary Nodules Found on Shoulder Arthroplasty Preoperative CT Scans.

With current emphasis on preoperative templating of anatomical and reverse shoulder arthroplasty (aTSA and rTSA, respectively), patients often receive thin slice (<1.0 mm) computerized tomography (CT) scans of the operative shoulder, which includes about two-thirds of the ipsilateral lung. The purpose of this study is to evaluate the prevalence and management of incidentally detected pulmonary nodules on preoperative CT scans for shoulder arthroplasty. In this single-center retrospective study, we queried records of aTSA and rTSA patients from 2015 to 2020 who received preoperative CT imaging of the shoulder. Compared to patients with negative CT findings, there were significantly more females (63.8% vs. 46.4%; P = .011), COPD (13.0% vs. 4.7%; P = .015), and asthma (18.8% vs. 6.9%; P = .003) among the patients with incidental nodules on CT. Binary logistic regression confirmed that female sex (odds ratio = 2.00; 95% CI = 1.04 to 3.88; P = .037), COPD history (OR = 3.02; 95% CI = 1.05 to 8.65; P = .040), and asthma history (OR = 3.17; 95% CI = 1.30 to 7.77; P = .011) were significantly associated with an incidental nodule finding. Incidental pulmonary nodules found on shoulder arthroplasty preoperative CT scans are often low risk in size with low risk of malignancy, and do not require further workup. This study may provide guidance to orthopedic surgeons on how to manage patients with incidental pulmonary nodules to increase chances of early cancer detection, avoid unnecessary referrals, reduce potentially harmful radiation exposure of serial CT scans, and improve cost efficiency.

Short Observation Period and Aggressive Discharge of Patients With Head Injury and Serial CT Scans.

Background: Many patients undergo two head computed tomography (CT) scans after mild traumatic brain injury (TBI). Radiographic progression without clinical deterioration does not usually alter management. Evidence-based guidelines offer potential for limited repeat imaging and safe discharge. This study characterizes patients who had two head CTs in the Emergency Department (ED), determines the change between initial and repeat CTs, and describes timing of repeat scans.Methods: This retrospective series includes all patients with head CTs during the same ED visit at an urban trauma center between May 1st, 2016 and April 30th, 2018. Radiographic interpretation was coded as positive, negative, or equivocal.Results: Of 241 subjects, the number of positive, negative, and equivocal initial CT results were 154, 50, and 37, respectively. On repeat CT, 190 (78.8%) interpretations were congruent with the original scan. Out of the 21.2% of repeat scans that diverged from the original read, 14 (5.8%) showed positive to negative conversion, 1 (.4%) showed positive to equivocal conversion, 2 (.88%) showed negative to positive conversion, 20 (8.3%) showed equivocal to negative conversion, and 14 (5.8%) showed equivocal to positive conversion. Average time between scans was 4.4 hours, and median length of stay was 10.2 hours.Conclusions: In this retrospective review, most repeat CT scans had no new findings. A small percentage converted to positive, rarely altering clinical management. This study demonstrates the need for continued prospective research to update clinical guidelines that could reduce admission and serial CT scanning for mild TBI.

Study on Repeat CT Scans in the Traumatic Brain Injury Management

Introduction: In recent trauma practice, a Computed Tomography (CT) scan is the initial study of choice to regulate the type, extent and severity of traumatic brain injury as well as to control the management protocol. There are no guidelines on the necessity of repeat CT scan. Objective: Our main aim in this present study was to determine whether serial CT scans demonstrated momentous change from the findings in the first CT scan and whether repeat scans had influence on management possibilities. Methodology: This cross sectional study was carried out at Department of Neurosurgery, Rangpur Medical College Hospital, from January 2016 to June 2017 where 80 patients’ data were evaluated on the basis of their history, clinical examination. On admission, a detailed history of the illness was taken from the patient or attendant, thorough neurological and general examinations were carried out, and findings of the performed investigations were recorded. On admission GCS were recorded. Result: In the study, out of all patients of group I maximum 40% patients belonged to 25 to 34 years age range and in group II maximum 35% belonged to 25 to 34 years age group. Also group I, 95% were male and 5% were female and in group II, 92.5% were male and 7.5% were female. Conclusion: From our result, we can conclude that for detecting new lesions or enlargement of existing lesions in traumatic brain injury repeat CT scans were found to be of significance which results in changing of management in a substantial percentage of patients.

Tumor Response Dynamics During First-Line Pembrolizumab Therapy in Patients With Advanced Non-Small-Cell Lung Cancer.

Eighty-eight patients treated with first-line pembrolizumab monotherapy were evaluated on serial computed tomography scans to characterize their quantitative tumor burden during therapy. Tumor burden dynamics were studied for the association with OS. The overall response rate was 42% (37/88), with the median tumor burden changes at the best overall response of -18.3% (range, -100.0% to +103.6%). Response rates were higher in men than in women (P = .05) and in patients with higher programmed cell death ligand-1 expression levels (P = .02). Tumor burden stayed below the baseline burden throughout therapy in 55 patients (63%). In an 8-week landmark analysis, patients with tumor burden below the baseline burden during the first 8 weeks of therapy had longer OS compared with patients who had ≥ 0% increase (median OS, 30.7 v 16.2 months; hazard ratio [HR] = 0.44; P = .01). In the extended Cox models, patients whose tumor burden stayed below the baseline burden throughout therapy had significantly reduced hazards of death (HR = 0.41, P = .003, univariate; HR = 0.35, P = .02, multivariate). Only one patient (1.1%) experienced pseudoprogression with initial tumor increase and subsequent tumor regression. In patients with advanced non-small-cell lung cancer treated with first-line single-agent pembrolizumab, tumor burden reduction below the baseline burden during therapy was an independent marker for prolonged OS, which may serve as a practical guide for treatment decisions.

Machine learning for lung texture analysis on thin-section CT: Capability for assessments of disease severity and therapeutic effect for connective tissue disease patients in comparison with expert panel evaluations.

The need for quantitative assessment of interstitial lung involvement on thin-section computed tomography (CT) has arisen in interstitial lung diseases including connective tissue disease (CTD). To evaluate the capability of machine learning (ML)-based CT texture analysis for disease severity and treatment response assessments in comparison with qualitatively assessed thin-section CT for patients with CTD. A total of 149 patients with CTD-related ILD (CTD-ILD) underwent initial and follow-up CT scans (total 364 paired serial CT examinations), pulmonary function tests, and serum KL-6 level tests. Based on all follow-up examination results, all paired serial CT examinations were assessed as "Stable" (n = 188), "Worse" (n = 98) and "Improved" (n = 78). Next, quantitative index changes were determined by software, and qualitative disease severity scores were assessed by consensus of two radiologists. To evaluate differences in each quantitative index as well as in disease severity score between paired serial CT examinations, Tukey's honestly significant difference (HSD) test was performed among the three statuses. Stepwise regression analyses were performed to determine changes in each pulmonary functional parameter and all quantitative indexes between paired serial CT scans. Δ% normal lung, Δ% consolidation, Δ% ground glass opacity, Δ% reticulation, and Δdisease severity score showed significant differences among the three statuses (P < 0.05). All differences in pulmonary functional parameters were significantly affected by Δ% normal lung, Δ% reticulation, and Δ% honeycomb (0.16 ≤r2 ≤0.42; P < 0.05). ML-based CT texture analysis has better potential than qualitatively assessed thin-section CT for disease severity assessment and treatment response evaluation for CTD-ILD.