Sequential Computed Tomography Images Research Articles

Aneurysm Sac Shrinkage at 1 Year after Fenestrated-Branched Endovascular Aortic Repair of Complex Aortic Aneurysms Offers Mid-Term Survival Advantage

To investigate the impact of 1-year changes in aneurysm sac diameter on patient survival after fenestrated-branched endovascular aortic repair (FB-EVAR) of complex abdominal (CAAA) or thoracoabdominal aortic aneurysms (TAAA). We reviewed the clinical data of patients enrolled in a prospective non-randomized study investigating FB-EVAR (2013-2022). Patients with sequential follow up computed tomography (CT) scans at baseline and 6 to 18 months after FB-EVAR were included in the analysis. Aneurysm sac diameter change was defined as the difference in maximum aortic diameter (MAD) from baseline measurements obtained in centerline of flow. Patients were classified as those with sac shrinkage (≥5mm) or failure to regress (<5mm or expansion) according to sac diameter change. Primary endpoint was all-cause mortality. Secondary endpoints were aortic-related mortality (ARM), aortic aneurysm rupture (AAR) and aorta-related secondary intervention. There were 549 patients treated by FB-EVAR. Of these, 463 patients (71% male, mean 74±8 years-old) with sequential CT imaging were investigated. Aneurysm extent was TAAA in 328 (71%) patients and CAAA in 135 (29%). Sac shrinkage occurred in 270 (58%) patients and failure to regress in 193 (42%) patients, including 19 (4%) patients with sac expansion at 1-year. Patients from both groups had similar cardiovascular risk factors, except for younger age among patients with sac shrinkage (73±8 vs. 75±8 years-old; P<.001). Median follow-up was 38 months (interquartile range, 18-51 months). Five-year survival estimate was 69%±4.1% for sac shrinkage and 46%±6.2% for failure to regress group. Survival estimates adjusted for confounders (age, chronic pulmonary obstructive disease, chronic kidney disease, congestive heart failure, and aneurysm extent) revealed a higher hazard of late mortality in patients with failure to regress (adjusted hazard ratio, 1.72; 95% confidence interval, 1.18-2.52; P=.005). Five-year cumulative incidences of ARM (1.1% vs. 3.1%, P=.30), AAR (0.6% vs. 2.6%, P=.20) and aorta-related secondary intervention (17±2.8% vs. 19±3.8%) were both comparable between the groups. Aneurysm sac shrinkage at 1 year is frequent after FB-EVAR and is associated with improved patient survival, while sac enlargement affects only a minority of patients. The low incidences of ARM and AAR indicate that failure to regress may serve as a surrogate marker for non-aortic-related death.

Three-Dimensional Voxel-Wise Quantitative Assessment of Imaging Features in Hepatocellular Carcinoma.

Voxel-wise quantitative assessment of typical characteristics in three-dimensional (3D) multiphase computed tomography (CT) imaging, especially arterial phase hyperenhancement (APHE) and subsequent washout (WO), is crucial for the diagnosis and therapy of hepatocellular carcinoma (HCC). However, this process is still missing in practice. Radiologists often visually estimate these features, which limit the diagnostic accuracy due to subjective interpretation and qualitative assessment. Quantitative assessment is one of the solutions to this problem. However, performing voxel-wise assessment in 3D is difficult due to the misalignments between images caused by respiratory and other physiological motions. In this paper, based on the Liver Imaging Reporting and Data System (v2018), we propose a registration-based quantitative model for the 3D voxel-wise assessment of image characteristics through multiple CT imaging phases. Specifically, we selected three phases from sequential CT imaging phases, i.e., pre-contrast phase (Pre), arterial phase (AP), delayed phase (DP), and then registered Pre and DP images to the AP image to extract and assess the major imaging characteristics. An iterative reweighted local cross-correlation was applied in the proposed registration model to construct the fidelity term for comparison of intensity features across different imaging phases, which is challenging due to their distinct intensity appearance. Experiments on clinical dataset showed that the means of dice similarity coefficient of liver were 98.6% and 98.1%, those of surface distance were 0.38 and 0.54 mm, and those of Hausdorff distance were 4.34 and 6.16 mm, indicating that quantitative estimation can be accomplished with high accuracy. For the classification of APHE, the result obtained by our method was consistent with those acquired by experts. For the WO, the effectiveness of the model was verified in terms of WO volume ratio.

Development of a deep learning-based method to diagnose pulmonary ground-glass nodules by sequential computed tomography imaging.

BackgroundEarly identification of the malignant propensity of pulmonary ground‐glass nodules (GGNs) can relieve the pressure from tracking lesions and personalized treatment adaptation. The purpose of this study was to develop a deep learning‐based method using sequential computed tomography (CT) imaging for diagnosing pulmonary GGNs.MethodsThis diagnostic study retrospectively enrolled 762 patients with GGNs from West China Hospital of Sichuan University between July 2009 and March 2019. All patients underwent surgical resection and at least two consecutive time‐point CT scans. We developed a deep learning‐based method to identify GGNs using sequential CT imaging on a training set consisting of 1524 CT sections from 508 patients and then evaluated 256 patients in the testing set. Afterwards, an observer study was conducted to compare the diagnostic performance between the deep learning model and two trained radiologists in the testing set. We further performed stratified analysis to further relieve the impact of histological types, nodule size, time interval between two CTs, and the component of GGNs. Receiver operating characteristic (ROC) analysis was used to assess the performance of all models.ResultsThe deep learning model that used integrated DL‐features from initial and follow‐up CT images yielded the best diagnostic performance, with an area under the curve of 0.841. The observer study showed that the accuracies for the deep learning model, junior radiologist, and senior radiologist were 77.17%, 66.89%, and 77.03%, respectively. Stratified analyses showed that the deep learning model and radiologists exhibited higher performance in the subgroup of nodule sizes larger than 10 mm. With a longer time interval between two CTs, the deep learning model yielded higher diagnostic accuracy, but no general rules were yielded for radiologists. Different densities of components did not affect the performance of the deep learning model. In contrast, the radiologists were affected by the nodule component.ConclusionsDeep learning can achieve diagnostic performance on par with or better than radiologists in identifying pulmonary GGNs.

Biomechanical effects of Skeletally anchored Class III elastics on the maxillofacial complex: a 3D finite element analysis

BackgroundAlthough, the outcomes and changes in the maxillofacial complex after the application of intraoral bone anchored Class III elastics, have been reported by multiple clinical studies, there was no finite element study to assess and evaluate the stress pattern and displacement on maxillomandibular complex with bimaxillary anchorage. The present study aims to evaluate the biomechanical effects on maxillomandibular complex of Skeletally anchored Class III elastics with varying angulations using the 3D finite element analysis.MethodologyTwo 3-dimensional analytical models were developed using the Mimics 8.11 (Materialise: Leuven, Belgium) and ANSYS software Version 12.1 (ANSYS Inc, Canonsburg, PA, USA) from sequential computed tomography images taken from a Skeletal Class III subject. The models were meshed into 465,091 tetrahedral elements and 101,247 nodes. Intraoral mechanics for skeletally anchored maxillary protraction (I-SAMP) were applied on two models i.e. A and B (without and with maxillary expansion respectively) between miniplates on maxilla and mandible on both right and left sides with three different angulations of forces—10°, 20° and 30°).ResultsAlthough the craniomaxillary complex in both the models (A and B) displaced forward while demonstrating rotations in opposite directions, the displacements and rotations decreased gradually with the increase of the angle of load application from 10° to 30°. The mandible rotated clockwise in both the simulations, but the displacement of mandibular surface landmarks was higher in Simulation A. However, the antero-inferior displacement of the glenoid fossa was higher in Simulation B than in A.ConclusionSignificant displacement of maxillofacial sutures and structures was witnessed with I-SAMP with maxillary expansion and Class III elastics for correction of Skeletal Class III with maxillary retrognathism. Thus, I-SAMP with maxillary expansion is a desired protocol for treatment of maxillary retrognathism. However, the prescribed angulation of the Class III elastics should be as low as possible to maximise the desired effects.

Deep Learning-based Quantification of Abdominal Subcutaneous and Visceral Fat Volume on CT Images

Develop a deep learning-based algorithm using the U-Net architecture to measure abdominal fat on computed tomography (CT) images. Sequential CT images spanning the abdominal region of seven subjects were manually segmented to calculate subcutaneous fat (SAT) and visceral fat (VAT). The resulting segmentation maps of SAT and VAT were augmented using a template-based data augmentation approach to create a large dataset for neural network training. Neural network performance was evaluated on both sequential CT slices from three subjects and randomly selected CT images from the upper, central, and lower abdominal regions of 100 subjects. Both subcutaneous and abdominal cavity segmentation images created by the two methods were highly comparable with an overall Dice similarity coefficient of 0.94. Pearson's correlation coefficients between the subcutaneous and visceral fat volumes quantified using the two methods were 0.99 and 0.99 and the overall percent residual squared error were 5.5% and 8.5%. Manual segmentation of SAT and VAT on the 555 CT slices used for testing took approximately 46 hours while automated segmentation took approximately 1 minute. Our data demonstrates that deep learning methods utilizing a template-based data augmentation strategy can be employed to accurately and rapidly quantify total abdominal SAT and VAT with a small number of training images.

Establishment and application of an artificial intelligence diagnosis system for pancreatic cancer with a faster region-based convolutional neural network.

Early diagnosis and accurate staging are important to improve the cure rate and prognosis for pancreatic cancer. This study was performed to develop an automatic and accurate imaging processing technique system, allowing this system to read computed tomography (CT) images correctly and make diagnosis of pancreatic cancer faster. The establishment of the artificial intelligence (AI) system for pancreatic cancer diagnosis based on sequential contrast-enhanced CT images were composed of two processes: training and verification. During training process, our study used all 4385 CT images from 238 pancreatic cancer patients in the database as the training data set. Additionally, we used VGG16, which was pre-trained in ImageNet and contained 13 convolutional layers and three fully connected layers, to initialize the feature extraction network. In the verification experiment, we used sequential clinical CT images from 238 pancreatic cancer patients as our experimental data and input these data into the faster region-based convolution network (Faster R-CNN) model that had completed training. Totally, 1699 images from 100 pancreatic cancer patients were included for clinical verification. A total of 338 patients with pancreatic cancer were included in the study. The clinical characteristics (sex, age, tumor location, differentiation grade, and tumor-node-metastasis stage) between the two training and verification groups were insignificant. The mean average precision was 0.7664, indicating a good training effect of the Faster R-CNN. Sequential contrast-enhanced CT images of 100 pancreatic cancer patients were used for clinical verification. The area under the receiver operating characteristic curve calculated according to the trapezoidal rule was 0.9632. It took approximately 0.2 s for the Faster R-CNN AI to automatically process one CT image, which is much faster than the time required for diagnosis by an imaging specialist. Faster R-CNN AI is an effective and objective method with high accuracy for the diagnosis of pancreatic cancer. ChiCTR1800017542; http://www.chictr.org.cn.

Expansion Thoracoplasty in Rabbit Model: Effect of Timing on Preserving Pulmonary Growth and Correcting Spine Deformity.

In a treatment-control animal study expansion thoracoplasty (ET) was performed in a juvenile rabbit model of thoracic insufficiency syndrome (TIS) and benefits to thoracic development and respiratory function quantified. Rabbits treated early versus late were compared to age-matched normal and disease control rabbits through to skeletal maturity. Evaluate (1) how ET changes the natural TIS disease trajectory and (2) how timing of ET affects changes in spine growth, lung growth, and respiratory mechanics. Pulmonary growth potential is thought to diminish with age; thus, early therapeutic intervention may increase pulmonary growth in children with TIS. However, no direct empirical evidence exists to support this treatment paradigm. Convex left scoliosis and resultant TIS was induced in 3-week-old rabbits via surgical rib tethering. We compare the efficacy of ET performed at 7 weeks and expanded at 11 weeks (early, n = 7) versus only at 11 weeks of age (late, n = 7) in preserving lung growth and respiratory function relative to normal (n = 8) and disease (n = 10) rabbits. Sequential computed tomography images and pulmonary function testing was performed to quantify spine curvature, lung growth, and respiratory volumes. At 28 weeks of age chest wall elastance was measured in vivo then acinar complexity analyzed histologically via radial alveolar counts. ET performed early or late altered the predicted trajectory of spine deformity, pulmonary growth inhibition, and respiratory dysfunction seen in disease rabbits. Growth was not significantly different between early and late rabbits and post-treatment gains remained below those of age-matched normal rabbits. Chest wall elastance was impaired by ET and more so in early rabbits, there were no differences in pulmonary elastance. ET interrupted the natural progression of deformity and pulmonary hypoplasia associated with spine curvature in disease rabbits. However, growth benefits are only seen in cases of the most severe initial deformity and must be balanced against the further impairment to chest wall function associated with repetitive surgery. N/A.

Attack of the Clone: HCC Tract Seeding Following RFA

A 42-year-old obese male, accidentally detected to be hepatitis B surface antigen (HBsAg) positive, presented to us in 2006. Patient was negative for antibodies to hepatitis C virus (anti-HCV) and hepatitis B envelope antigen (HBeAg) and had hepatitis B (HBV) DNA viral load of 525,073 IU/ml. He had mild thrombocytopenia, mildly elevated serum transaminases, and hypoalbuminemia. Ultrasonography revealed two hypoechoic lesions in the right lobe of liver. Serum alpha-fetoprotein (AFP) levels were 4.99 IU/ml whereas upper gastrointestinal endoscopy revealed small esophageal varices. Patient was considered to have ‘e’ negative chronic hepatitis B related chronic liver disease and was started on tablet Lamivudine 100 mg once a day. Computed tomography (CT) showed two lesions in the segment V and VI of liver, measuring 5 and 3 cm in the widest dimensions, enhancing on arterial phase and without any portal vein involvement, and were diagnosed as hepatocellular carcinoma (HCC). Patient underwent selective transarterial chemoembolization (TACE) of the liver nodules. Post-TACE sequential surveillance CT and magnetic resonance (MR) imaging revealed nonviable tumor, with persistently normal AFP levels and a stable liver biochemistry. An MR imaging in November 2010 showed a new 3.1 cm lesion posterior to and abutting the previously TACE’d lesion, with imaging characteristics of local recurrence, which was subjected to radiofrequency ablation (RFA). Subsequent MR scans revealed unchanged TACE’d or RFA’d lesion. A scan done in February 2012 showed two new discrete enhancing nodules, ranging from 5 to 8 mm, in the lateral pareitis, located within the internal oblique and in the intermuscular plane, along the RFA tract, with persistent enhancement on the delayed venous phase. Patient noticed a palpable lump at the same site in a few months, and the lump appeared to be increasing gradually in size over a period of months. By December 2013, the lesion reached a size of 10.8 × 8.0 × 7.6 demonstrating heterogeneous arterioportal phase enhancement with progressive washout on delayed venous phase, a delayed enhancing rim, and intralesional fat and hemorrhage (Figure A), highly suggestive of recurrent HCC due to tract seeding along the site of previous RFA. Patient underwent wide local excision of the tumor (Figure B) in July 2014, which was found adherent to 10th and 11th ribs but without any intraperitoneal extension. The histology of the excised specimen showed moderately differentiated hepatocellular carcinoma (Figure C).

Pain control in patients with hepatocellular carcinoma treated by percutaneous radiofrequency ablation: comparison of the efficacy of one-shot and continuous intravenous fentanyl delivery

Hepatic percutaneous radiofrequency ablation (RFA) is usually performed with the patient under deep intravenous (i.v.) sedation or general anesthesia. Nonetheless, many patients report pain during and/or after the procedure. To perform a prospective study of pain control obtained by the i.v. one-shot delivery and the continuous i.v. infusion of fentanyl in patients with hepatocellular carcinoma (HCC) treated by RFA. Between April 2007 and March 2010, 83 patients with 106 HCCs underwent percutaneous RFA. All HCCs were addressed by computed tomography (CT)-guided percutaneous RFA performed within 5 h of embolization of the tumor vessels with iodized oil and gelatin sponges. Standard anesthesia consisted of 10 mL of 1% lidocaine injected locally. For conscious sedation, group one patients (n = 41) were injected i.v. with 100 µg of fentanyl before and 100 µg of fentanyl 30 min after percutaneous RFA. In group two (n = 42) we delivered fentanyl by continuous i.v. infusion at 100 µg/h during RFA. Upon request, patients in both groups also received 5 mg of diazepam i.v. for pain during the RFA procedure. The severity of pain experienced by all patients was evaluated on a visual analogue scale (VAS) and complications elicited by the anesthesia regimens were recorded. We also assessed the effectiveness of the treatment on sequential follow-up CT and/or magnetic resonance imaging (MRI) at 3-month intervals. Percutaneous RFA was technically successful in all 83 patients. Two patients in group one (4.8%) and one patient in group two (2.4%) manifested residual enhancement 3 months post RFA. There was no significant difference in the local recurrence rate between the two groups. At 4.0 ± 1.8 for group one and 3.4 ± 1.9 for group two, the VAS score was not significantly different. Major fentanyl or diazepam toxicity was recorded in 11 patients (24.4%) in group one and two patients (4.8%) in group two; the difference was statistically significant (P < 0.01). The continuous infusion of fentanyl provided effective and safe analgesia in HCC patients undergoing percutaneous RFA.

The Hill-Sachs Lesion: Volumetric modeling using Three-Dimensional Computed Tomography Reconstructions

Objectives:The purposes of our study were to identify the volume and relative location of Hill-Sachs lesions, measure the amount of glenoid bone loss in patients who have existing Hill-Sachs lesions, and finally draw any correlations that exist between increased glenoid bone loss and increased Hill-Sachs volume.Methods:A total of 217 consecutive three-dimensional (3D) Computed Tomography (CT) scans were reviewed for the presence and measurement of Hill-Sachs volume and location. Hill-Sachs volume was measured by measuring the size of the Hill-Sachs defect in sequential CT images and a 3D model was created to measure the volume of the defect using Osirix (Osirix Imaging Software, Osirix-viewer.com). The Hill-Sachs lesion was then quantified in terms of both location and size. Further, older classification systems were applied to the data to draw comparison. Location of the lesion was measured by utilizing anterior and posterior margins of the lesion in relation to the biceps groove to give a clock face location. The height, depth and length of each lesion were also recorded in its greatest dimension. In addition a 3D model of the individual Hill-Sachs lesion was generated to observe the rough shape of the bony defect.Results:The Hill-Sachs lesion was identified in 60% of patients, N=130. The mean volume of the Hill-Sachs lesions was 1.22 cm3, with a range of 0.13 cm3 to 5.3 cm3. The three dimensional shape of the Hill-Sachs lesion was consistently an orange slice. Using prism measurements the average volume was 3.19 cm3 with a range of 0.33 cm3 to 9.76 cm3. Average arc of the circle of each lesion measured at the axial mid point (10 mm below the top of the humeral head) was 68.9° with a range of 9.49° to 165.88°. The average depth of the lesion was 6.7 mm with a range of 2.8 mm to 11.1 mm.Conclusion:This study identified a unique yet important way to measure the absolute size of the Hill-Sachs lesion in the shoulder. This method is positively correlated with previous measurement systems, but utilizes novel methods to fully measure the unique shape of Hill-Sachs lesions. Using absolute measures not only increases accuracy, but 3D modeling also shows the nature of the defect and location in order to consider operative repair of the lesion. However, the Hill-Sachs lesion only describes one side of the problem, with this data side by side comparison with glenoid bone loss is needed to fully understand the nature of shoulder instability that is a bipolar problem.

Blindness : An Uncommon Presentation of Colloid Cysts = العمى : عرض إستثنائي لتكيسات غروانية

Colloid cysts may obstruct the foramina of Monro and lead to acute hydrocephalus.1,2 In patients with colloid cysts, intraventricular pressure can increase suddenly due to acute obstructive hydrocephalus.3,4 A sudden and dramatic rise in ventricular pressure may lead to cerebral herniation, infarction and may result in death.4 These images show a patient who was admitted to Ataturk Training and Research Hospital, Ankara, Turkey, with complaints of visual loss. Acute bilateral blindness is an emergent condition that may signal a life-threatening disease. A 46-year-old man with no previous neurological complaints was admitted to our hospital with symptoms of headache, loss of consciousness and the progressive loss of vision. A physical examination revealed less than 20/20 central visual acuity. Moderate hydrocephalus and bilateral periventricular oedema were detected by a computed tomography (CT) scan performed in the Emergency Department [Figure 1]. Magnetic resonance (MR) imaging and diffusion-weighted imaging (DWI) were recommended for the patient, as the aetiology of hydrocephalus could not be determined exactly by the initial CT scan. On MR imaging, a colloid cyst and acute hydrocephalus were detected. In addition, diffusion-weighted imaging (DWI) revealed areas with restricted diffusion on the bilateral occipital lobes. As a result of these findings, ventriculoperitoneal shunting was performed five hours after the patient was admitted. MR images were obtained after the procedure, which detected regression in the sizes of the lateral ventricles and in the periventricular cerebrospinal fluid reabsorption [Figure 1]. In addition, there were infarctions in the bilateral occipital lobes and no recovery of vision. The posterior circulation was normal and there were early subacute infarctions in the occipital lobes on the MR images taken one week after the shunt therapy. There was no improvement in the loss of vision of the patient at the second week follow-up. Figure 1 A–K: Preoperative computed tomography (CT) and postoperative magnetic resonance (MR) images of the patient. A, B & C: Preoperative sequential axial CT images showing hydrocephalus and periventricular oedema. D, E, F & G: Postoperative axial ...

MULTIFOCALCRYPTOCOCCUS NEOFORMANSVAR.NEOFORMS: INFECTION, TREATMENT, AND MONITORING BY SERIAL COMPUTED TOMOGRAPHY IN A SCHMIDT'S RED-TAILED GUENON (CERCOPITHECUS ASCANIUS SCHMIDTI)

A 9-yr-old, female, intact Schmidt's red-tailed guenon (Cercopithecus ascanius schmidti) presented with an acute swelling, consistent with an abscess over the right hip. Cytology, culture, and polymerase chain reaction (PCR) results from material within the abscess and serum titers were all indicative of a Cryptococcus neoformans infection. Thoracic radiographs and computed tomography (CT) revealed a consolidated right caudal lung lobe associated with an endobronchial mass. Pulmonary Cryptococcus infection and systemic disease was confirmed with positive brush cytology and bronchoalveolar lavage (BAL). Culture and sensitivity, minimum inhibitory concentration values, and serum fluconazole level results were used to develop and monitor treatment efficacy for this animal. Sequential thoracic radiographs, CT images, bronchoscopy, BAL, and serology were used to monitor response to therapy. Five months after initial diagnosis, pregnancy was confirmed and the frequency of immobilizations for recheck serology and diagnostic imaging was decreased to lessen radiation exposure and physiologic stress to the dam and fetus. Long-term administration of oral fluconazole was well accepted and effective at treating the multifocal C. neoformans infection. No long-term adverse effects of therapy were observed, and repeated diagnostics were well tolerated. Advanced imaging modalities and serum drug levels were critical to the assessment, monitoring, and treatment of infection in this animal and should be considered for other cases.

A first-in-human, phase 1, dose-escalation study of dinaciclib, a novel cyclin-dependent kinase inhibitor, administered weekly in subjects with advanced malignancies

BackgroundDinaciclib, a small-molecule, cyclin-dependent kinase inhibitor, inhibits cell cycle progression and proliferation in various tumor cell lines in vitro. We conducted an open-label, dose-escalation study to determine the safety, tolerability, and bioactivity of dinaciclib in adults with advanced malignancies.MethodsDinaciclib was administered starting at a dose of 0.33 mg/m2, as a 2-hour intravenous infusion once weekly for 3 weeks (on days 1, 8, and 15 of a 28-day cycle), to determine the maximum administered dose (MAD), dose-limiting toxicities (DLTs), recommended phase 2 dose (RP2D), and safety and tolerability. Pharmacodynamics of dinaciclib were assessed using an ex vivo phytohemagglutinin lymphocyte stimulation assay and immunohistochemistry staining for retinoblastoma protein phosphorylation in skin biopsies. Evidence of antitumor activity was assessed by sequential computed tomography imaging after every 2 treatment cycles.ResultsForty-eight subjects with solid tumors were treated. The MAD was found to be 14 mg/m2 and the RP2D was determined to be 12 mg/m2; DLTs at the MAD included orthostatic hypotension and elevated uric acid. Forty-seven (98%) subjects reported adverse events (AEs) across all dose levels; the most common AEs were nausea, anemia, decreased appetite, and fatigue. Dinaciclib administered at the RP2D significantly inhibited lymphocyte proliferation, demonstrating a pharmacodynamic effect. Ten subjects treated at a variety of doses achieved prolonged stable disease for at least 4 treatment cycles.ConclusionsDinaciclib administered every week for 3 weeks (on days 1, 8, and 15 of a 28-day cycle) was generally safe and well tolerated. Initial bioactivity and observed disease stabilization support further evaluation of dinaciclib as a treatment option for patients with advanced solid malignancies.Trial registrationClinicalTrials.gov # NCT00871663

Acute bronchospasm and resolution captured on dynamic CT

Computed tomography (CT) imaging provides a noninvasive window beneath the skin, defines lung pathology, and facilitates virtual and multimodality fusion interventions. A CT scan of acute bronchospasm is shown during a CT-guided lung intervention. Dynamic or sequential CT imaging can depict and perhaps even quantify acute reversible bronchospasm, and could potentially play a role in better understanding pharmacologic interventions for reactive airways and the resulting effects.

Radial displacement of clinical target volume in node negative head and neck cancer

PurposeTo evaluate the radial displacement of clinical target volume in the patients with node negative head and neck (H&N) cancer and to quantify the relative positional changes compared to that of normal healthy volunteers.Materials and MethodsThree node-negative H&N cancer patients and five healthy volunteers were enrolled in this study. For setup accuracy, neck thermoplastic masks and laser alignment were used in each of the acquired computed tomography (CT) images. Both groups had total three sequential CT images in every two weeks. The lymph node (LN) level of the neck was delineated based on the Radiation Therapy Oncology Group (RTOG) consensus guideline by one physician. We use the second cervical vertebra body as a reference point to match each CT image set. Each of the sequential CT images and delineated neck LN levels were fused with the primary image, then maximal radial displacement was measured at 1.5 cm intervals from skull base (SB) to caudal margin of LN level V, and the volume differences at each node level were quantified.ResultsThe mean radial displacements were 2.26 (±1.03) mm in the control group and 3.05 (±1.97) in the H&N cancer patients. There was a statistically significant difference between the groups in terms of the mean radial displacement (p = 0.03). In addition, the mean radial displacement increased with the distance from SB. As for the mean volume differences, there was no statistical significance between the two groups.ConclusionThis study suggests that a more generous radial margin should be applied to the lower part of the neck LN for better clinical target coverage and dose delivery.

Percutaneous Radiofrequency Ablation for Pulmonary Metastases from Hepatocellular Carcinoma: Results of a Multicenter Study in Japan

Purpose To retrospectively evaluate technical success, effectiveness, complications, patient survival, and prognostic factors with percutaneous radiofrequency (RF) ablation for pulmonary metastases resulting from hepatocellular carcinoma (HCC). Materials and Methods Thirty-two patients from six institutions were included, with a total of 83 pulmonary metastases treated in 65 sessions. RF ablation was always performed percutaneously with computed tomography (CT) guidance. Primary endpoints were technical success and technique effectiveness. Technique effectiveness was evaluated based on sequential follow-up CT images. Secondary study endpoints were complications, patient survival, and determination of prognostic factors. Complications were classified as major or minor. Prognostic factors were determined by analyzing multiple variables with the log-rank test. Results Technical success rate was 100%. Primary technique effectiveness rates were 92% each at 1, 2, and 3 years. Major and minor complications occurred after 16 (25%) and 23 (35%) of the 65 sessions, respectively. The median follow-up period was 20.5 months. Overall survival rates were 87% at 1 year and 57% each at 2 and 3 years (median and mean survival times, 37.7 mo and 43.2 mo, respectively). Significantly better survival rates were obtained in cases of (i) no viable intrahepatic recurrence ( P < .001), (ii) Child-Pugh class A disease ( P < .001), (iii) absence of liver cirrhosis ( P < .001), (iv) absence of hepatitis C virus infection ( P = .006), and (v) α-fetoprotein level of 10 ng/mL or lower ( P = .007) at the time of RF ablation. Conclusions RF ablation appears effective, with an acceptable safety profile, in selected patients with pulmonary metastases resulting from HCC.

Separation of Left and Right Lungs Using 3-Dimensional Information of Sequential Computed Tomography Images and a Guided Dynamic Programming Algorithm

This article presents a new computerized scheme that aims to accurately and robustly separate left and right lungs on computed tomography (CT) examinations. We developed and tested a method to separate the left and right lungs using sequential CT information and a guided dynamic programming algorithm using adaptively and automatically selected start point and end point with especially severe and multiple connections. The scheme successfully identified and separated all 827 connections on the total 4034 CT images in an independent testing data set of CT examinations. The proposed scheme separated multiple connections regardless of their locations, and the guided dynamic programming algorithm reduced the computation time to approximately 4.6% in comparison with the traditional dynamic programming and avoided the permeation of the separation boundary into normal lung tissue. The proposed method is able to robustly and accurately disconnect all connections between left and right lungs, and the guided dynamic programming algorithm is able to remove redundant processing.

Biomechanical Effects of Fixed Functional Appliance on Craniofacial Structures

To evaluate displacement and stress distribution on craniofacial structures associated with fixed functional therapy. A finite element model of the human skull was constructed from sequential computed tomography images at 2-mm intervals using a dry adult human skull. In this study, linear, four-nodal, tetramesh and triangular shell elements were used with six degrees of freedom at each of their unstrained nodes: three translations (x, y, and z) and three rotations (around the x-, y-, and z-axes). The entire mandible moved anteroinferiorly. Maximum displacement was observed in the parasymphyseal and midsymphyseal regions. The pterygoid plate was displaced in a posterosuperior direction. The anteroinferior displacement of the mandibular dentition was most pronounced in the incisor region, while the maxillary dentition was displaced posterosuperiorly. The entire dentition experienced tensile stress except for the maxillary posterior teeth. Tensile stress was also demonstrated at point A, the pterygoid plates, and the mandible, and minimal compressive stress was demonstrated at anterior nasal spine. Maximum tensile stress and von Mises stresses occurred in the condylar neck and head. Fixed functional therapy causes a posterosuperior displacement of the maxillary dentition and pterygoid plate and thus can contribute to the correction of Class II malocclusion. The displacement was more pronounced in the dentoalveolar region as compared to the skeletal displacement. All dentoalveolar structures experienced tensile stress, except for anterior nasal spine and the maxillary posterior teeth.

Impact of respiratory movement on the computed tomographic images of small lung tumors in three-dimensional (3D) radiotherapy

Purpose: Three-dimensional (3D) treatment planning has often been performed while patients breathe freely, under the assumption that the computed tomography (CT) images represent the average position of the tumor. We investigated the impact of respiratory movement on the free-breathing CT images of small lung tumors using sequential CT scanning at the same table position. Methods: Using a preparatory free-breathing CT scan, the patient’s couch was fixed at the position where each tumor showed its maximum diameter on image. For 16 tumors, over 20 sequential CT images were taken every 2 s, with a 1-s acquisition time occurring during free breathing. For each tumor, the distance between the surface of the CT table and the posterior border of the tumor was measured to determine whether the edge of the tumor was sufficiently included in the planning target volume (PTV) during normal breathing. Results: In the sequential CT scanning, the tumor itself was not visible in the examination slice in 21% (75/357) of cases. There were statistically significant differences between lower lobe tumors (39.4%, 71/180) and upper lobe tumors (0%, 0/89) ( p < 0.01) and between lower lobe tumors and middle lobe tumor (8.9%, 4/45) ( p < 0.01) in the incidence of the disappearance of the tumor from the image. The mean difference between the maximum and minimum distances between the surface of the CT table and the posterior border of the tumor was 6.4 mm (range 2.1–24.4). Conclusion: Three-dimensional treatment planning for lung carcinoma would significantly underdose many lesions, especially those in the lower lobe. The excess “safety margin” might call into question any additional benefit of 3D treatment. More work is required to determine how to control respiratory movement.

口唇口蓋裂患者の鼻上顎複合体のＣＴ画像による三次元解析

This study was designed to clarify the three dimensional features of naso-maxillary complex in cleft lip and palate (CLP) by using computed tomography (CT) and to examine its change following an upper dental arch expansion. Sequential CT images with 2mm-thickness were obtained for 11 unilateral CLP boys (UCLP), 6 bilateral CLP boys (BCLP) and 4 boys without cleft (non-cleft). Additionally, two serial sets of upper dental cast before and after dental arch expansion coupled with CT images in UCLP were used to evaluate the effect of dental arch expansion on the naso-maxillary complex. UCLP demonstrated a remarkable naso-maxillary deformity characterized by a decreased volume of maxillary sinus in comparison with the non-cleft patients. Both the volume and shape of nasal cavity were significantly different between the cleft and non cleft side. Naso-maxillary morphology of BCLP, however, was similar to that of the non cleft except for the decreased volume of alveolar arch. Comparative study of UCLP and BCLP showed a significant difference in naso-maxillary morphology. There were some significant correlations between the dental arch expansion and change of each naso-maxillary component, suggesting the effect of expansion stress on the naso-maxillary complex in UCLP. However, deformation caused by expansion stress varied, depending on each component of the naso-maxillary complex.