Multidetector-row Computed Tomography Research Articles

Artificial intelligence in image reconstruction: The change is here.

Innovations in CT have been impressive among imaging and medical technologies in both the hardware and software domain. The range and speed of CT scanning improved from the introduction of multidetector-row CT scanners with wide-array detectors and faster gantry rotation speeds. To tackle concerns over rising radiation doses from its increasing use and to improve image quality, CT reconstruction techniques evolved from filtered back projection to commercial release of iterative reconstruction techniques, and recently, of deep learning (DL)-based image reconstruction. These newer reconstruction techniques enable improved or retained image quality versus filtered back projection at lower radiation doses. DL can aid in image reconstruction with training data without total reliance on the physical model of the imaging process, unique artifacts of PCD-CT due to charge sharing, K-escape, fluorescence x-ray emission, and pulse pileups can be handled in the data-driven fashion. With sufficiently reconstructed images, a well-designed network can be trained to upgrade image quality over a practical/clinical threshold or define new/killer applications. Besides, the much smaller detector pixel for PCD-CT can lead to huge computational costs with traditional model-based iterative reconstruction methods whereas deep networks can be much faster with training and validation. In this review, we present techniques, applications, uses, and limitations of deep learning-based image reconstruction methods in CT.

Quantitative Analysis of the Deltoid Ligament Degradation in Chronic Ankle Instability Patients using the CT Value

Category:Ankle; OtherIntroduction/Purpose:Chronic lateral ankle instability (CLAI) that is developed after multiple lateral ankle ligament injury lead to ankle osteoarthritis. Although isolated deltoid ligament injury is rare compared to lateral ankle ligament injury, deltoid ligament tear, especially deep posterior tibiotalar ligament (PTT) can be observed arthroscopically in CLAI patients. Unphysiological loading of the ankle joint with CLAI might cause degradation of the deltoid ligament. This study aimed to investigate image findings of the deltoid ligament using computed tomography (CT) value for quantitative analysis of degenerative ligament changes in CLAI patients.Methods:Among the enrolled patients who underwent ankle magnetic resonance imaging (MRI) and CT scans of the ankle, this retrospective analysis included 24 ankles without ankle osteoarthritis, osteochondral lesion of the talus (OLT), flatfoot and ankle fractures (14 males and 10 females; mean age, 42.8 years) as a control group, and 14 CLAI ankles without OLT (7 males and 7 females; mean age, 31.1 years) as CLAI group. The CT scans were performed using a 64-slice multidetector row CT. Deep PTT was detected on coronal T2-weighted MR images. Both the coronal MR and CT images were matched for analysis, then average CT values were measured using the region of interest that was applied to the detected area of deep PTT on the CT images.Spearman’s correlation coefficient was used to evaluate the correlation between age and CT value in the control group.Results:The strong negative correlation was identified between age and CT value in the control group (Spearman ρ= -0.88; p< 0.001). The CT value of the deep PTT are degraded with aging. Mean CT value of deep PTT in participants under 60 years old were 79.9 HU (95% CI, 75.1-84.8) in the control group (18 ankles), and 66.5 HU (95% CI, 58.6-74.5) in the CLAI group (14 ankles) (Welch’s t test; p = 0.005).Conclusion:MRI techniques and protocols recently have been developed, however, some limitations remain such as a quantitative evaluation of the ligament. Our findings suggest that the CLAI can lead to degradation of the deltoid ligament via an overloading of medial ankle structures. Additionally, CT values should be useful for quantitatively evaluating ligament status including degenerative changes.

Optimization of paranasal sinus CT procedure: Ultra-low dose CT as a roadmap for pre-functional endoscopic sinus surgery.

To assess image quality and radiation dose associated with ultra-low dose CT protocol for patients with benign paranasal sinus diseases undergoing functional endoscopic surgery (FESS). We scanned the head portion of Alderson RANDO phantom on a second generation, dual-source, multidetector-row CT scanner (Siemens Definition Flash) using standard-dose and five low-dose protocols. Two radiologists assessed the image quality for each protocol to determine best ultra-low-dose protocols for imaging patients with benign paranasal sinus diseases undergoing FESS. The ultra-low-dose CT protocols were then used for scanning. Thereafter, 40 adult patients (age range 18-54years, M:F 23:17) were scanned with the four low dose scanning protocols (10 patients per protocol). On both transverse and coronal reformatted CT images, two radiologists assessed visibility of key anatomic landmarks for FESS on a 2-point scale (1=clear and complete visualization; 2=suboptimal visualization). Data were analyzed with descriptive statistics and Cohen's kappa coefficient for interobserver agreement. In phantom study, the lowest dose scan protocol (CTDIvol 2.1mGy, 70kV, 75 mAs) was unacceptable due to poor image quality. For patient studies, both radiologists gave acceptable image quality scores for ultra-low-dose scan protocol with axial scan mode, automatic tube potential selection and tube current modulation (CTDIvol 2.2mGy; DLP 22.9mGy.cm) with up to 60% lower dose compared to prior standard-dose CT (CTDIvol 5.3mGy; DLP 73.5mGy.cm). Ultra-low-dose CT protocol provides sufficient image quality for scanning patients undergoing functional endoscopic surgery for benign paranasal sinus diseases.

Errors in MDCT diagnosis of acute mesenteric ischemia.

The causes of diagnostic errors during daily medical practice can be several, mainly attributable to perceptual, interpretive and communication factors. The eventuality of radiological error is much more amplified in the emergency setting where a high number of complex multidetector-row computed tomography (MDCT) images must be evaluated quickly and critical time decisions need to be taken. In particular, in this context, the diagnosis of vascular intestinal diseases represents a crucial and difficult challenge in case of acute abdominal pain given the importance of being able to identify patient with high suspicious for intestinal ischemia and for a specific patient to judge if his ischemia is reversible or irreversible. Awareness of potential biases which can lead to diagnostic errors together with an extensive knowledge of the imaging features of these pathologies can lead to promptly recognize them with fewer mistakes, improving patients' outcome. This article reviews the MDCT findings of acute intestinal ischemia and acute colonic ischemia and analyzes the main types of diagnostic errors, underlining the importance of being familiarized with them to avoid misdiagnosis.

Dynamic changes in longitudinal stretching of the spinal cord in thoracic spine: Focus on the spinal cord occupation rate of dural sac

ObjectivesThis study aimed to evaluate the anteroposterior diameters and cross-sectional areas of the dural sac and spinal cord in the thoracic spine, to elucidate the spinal cord occupation rate of the dural sac in these dynamic changes for each level using multidetector-row computed tomography (MDCT). Patients and MethodsFifty patients with cervical or lumbar spinal disease were prospectively enrolled. After preoperative myelography, MDCT was performed at maximum passive flexion and extension. The anteroposterior diameter and cross-sectional area of the dural sac and spinal cord in the axial plane and the thoracic spinal cord length in the sagittal plane were measured. The spinal cord occupation rate in the dural sac was calculated. ResultsThe spinal cord occupation rate of the dural sac in anteroposterior diameter was lower on flexion than on extension, with significant differences from the T1/T2 to T11/T12 levels (p < 0.0001). The spinal cord occupation rate of the dural sac in cross-sectional area was lower on flexion than on extension, with significant differences except from T3/T4 to T6/T7 levels (p < 0.01). There was a bimodal increase in the occupation rate with elevations at the cervicothoracic junction and thoracolumbar junction. The thoracic spinal cord length on flexion was significantly longer than that on extension (p < 0.0001). ConclusionsThe spinal cord occupation rate of the dural sac was lower on flexion than on extension, despite thoracic spine being considered a rigid region. The dynamic changes in longitudinal stretching and shrinkage of the spinal cord affected the occupation rate.

Study of the Portal Branches Arising from the Cranial Part of the Umbilical Portion of the Left Portal Vein: Implications for Anatomic Right Hepatic Trisectionectomy.

In "anatomic" right hepatic trisectionectomy for advanced perihilar cholangiocarcinoma, the left hepatic duct is divided at the left side of the umbilical portion (UP) of the left portal vein (LPV). For this reason, the left hepatic duct is completely detached from the UP after all division of the portal branches arising cranially from the UP. However, little is known about these thin portal branches. Using 3D imaging processing software, we examined the portal branches arising cranially from the UP of the LPV in 100 patients who underwent multidetector row computed tomography (MDCT). Special attention was paid to the portal branch running to the left lateral sector, designated as the left cranio-lateral branch. The left cranio-lateral portal branch number was 0 in 57 patients, 1 in 32 patients, and 2 in 11 patients. Thus, 54 left cranio-lateral branches were identified, arising from near the cul-de-sac of the UP, from near the elbow of the LPV, or from the UP trunk. The median volume of the territory supplied by the left cranio-lateral portal branch was 21mL (range, 5-47mL), and the median ratio to the left lateral sector was 11.8% (range, 1.7-25.0%). Approximately 40% of patients had the left cranio-lateral portal branches arising cranially from the UP and running to the left lateral sector. When planning anatomic right hepatic trisectionectomy, the presence or absence of this branch should be checked by using 3D imaging with MDCT.

Radiation dose and repeatability of aortic valve measurement by multidetector row computed tomography to assess eligibility for transcatheter aortic valve implantation.

Aortic valve stenosis is among the most common valvular defects in developed countries. In the assessment of eligibility for transcatheter aortic valve implantation (TAVI), multidetector row computed tomography (MDCT) is performed to determine the precise dimensions of the aortic valve, the topography of the aortic ostium and the ability to use various arterial access routes. To evaluate the relationships between the radiation dose and the repeatability of measurements of dimensions of the aortic valve in MDCT performed before TAVI. The study involved a group of 60 consecutive patients undergoing MDCT before TAVI. The radiation dose was expressed as computed tomography dose index volume (CTDIvol) and dose length product (DLP). The coefficient of variation (CV) of each measurement was defined as the standard deviation (SD) of the measurements/mean measurement × 100%, based on the measurements performed independently by 2 radiologists. A statistically significant negative linear correlation was observed between the DLP value of the MDCT before TAVI, and the CV of the measurement of the minimum dimension of the aortic annulus (r = -0.25; p < 0.05). Lower DLP doses of the MDCT before TAVI constitute an independent factor associated with a higher CV for the measurement of the minimum dimension of the aortic annulus. It is proposed that tests using lower radiation doses should be followed by an assessment of the degree of repeatability of the aortic valve sizing.

Intraductal tubulopapillary neoplasms with rupture of the distal main pancreatic duct: a case report

BackgroundIntraductal tubulopapillary neoplasm (ITPN) is a rare and newly described entity defined as an intraductal, grossly visible, tubule-forming epithelial neoplasm with high-grade dysplasia and ductal differentiation without overt production of mucin. Because of its rarity, the clinical and molecular aspects of ITPN have not been fully investigated.Case presentationA 73-year-old woman presented to a local hospital with epigastric discomfort and pain. Abdominal multidetector-row computed tomography (MDCT) revealed a 2.5-cm hypovascular tumor in the pancreatic body with distal pancreatic duct dilatation and a slightly low-density area spreading over the ventral side of the pancreatic body. Endoscopic ultrasonography and fine-needle biopsy of the tumor revealed adenocarcinoma of the pancreas. She was referred to our hospital 2 months later. MDCT performed at our hospital showed no significant change in the tumor size or pancreatic duct dilatation. However, the low-density area at the ventral side of the pancreas had shrunk; therefore, this finding was considered to have been an inflammatory change. Under a preoperative diagnosis of resectable pancreatic ductal adenocarcinoma, distal pancreatectomy was performed. The final diagnosis was ITPN with associated invasive carcinoma. Macroscopically and microscopically, the main pancreatic duct (MPD) had ruptured at the distal side of the tumor, and the fistula connected the MPD and extrapancreatic scar tissue.ConclusionsITPN with rupture of the pancreatic duct is extremely rare. In the present case, a sudden increase in the pancreatic duct internal pressure or acute inflammation likely caused the rupture of the MPD.

Preoperative computed tomography-guided disease-free survival prediction in gastric cancer: a multicenter radiomics study.

Preoperative and noninvasive prognosis evaluation remains challenging for gastric cancer. Novel preoperative prognostic biomarkers should be investigated. This study aimed to develop multidetector-row computed tomography (MDCT)-guided prognostic models to direct follow-up strategy and improve prognosis. A retrospective dataset of 353 gastric cancer patients were enrolled from two centers and allocated to three cohorts: training cohort (n=166), internal validation cohort (n=83), and external validation cohort (n=104). Quantitative radiomic features were extracted from MDCT images. The least absolute shrinkage and selection operator penalized Cox regression was adopted to construct a radiomic signature. A radiomic nomogram was established by integrating the radiomic signature and significant clinical risk factors. We also built a preoperative tumor-node-metastasis staging model for comparison. All models were evaluated considering the abilities of risk stratification, discrimination, calibration, and clinical use. In the two validation cohorts, the established four-feature radiomic signature showed robust risk stratification power (P=0.0260 and 0.0003, log-rank test). The radiomic nomogram incorporated radiomic signature, extramural vessel invasion, clinical T stage, and clinical N stage, outperforming all the other models (concordance index=0.720 and 0.727) with good calibration and decision benefits. Also, the 2-yr disease-free survival (DFS) prediction was most effective (time-dependent area under curve=0.771 and 0.765). Moreover, subgroup analysis indicated that the radiomic signature was more sensitive in risk stratifying patients with advanced clinical T/N stage. The proposed MDCT-guided radiomic signature was verified as a prognostic factor for gastric cancer. The radiomic nomogram was a noninvasive auxiliary model for preoperative individualized DFS prediction, holding potential in promoting treatment strategy and clinical prognosis.

ODONTOGENIC MYXOMA: A CASE REPORT AND LITERATURE REVIEW

<h3>Background</h3> Odontogenic myxoma (OM) is a rare intraosseous neoplasm that is benign but locally aggressive. It is derived from the mesenchymal portion of the tooth germ. Even though it is a benign lesion, it can cause considerable morbidity because of its invasive nature. Therefore, it is important to delineate the margins of OM to achieve a better treatment outcome. We present the case of a mandibular odontogenic myxoma in a 72-year-old male patient, whose chief complaint was swelling and pain on the lower left side of the face. The patient underwent imaging at Tokyo Medical and Dental Hospital for further evaluation. <h3>Objective</h3> The aim of this report is to present a case of odontogenic myxoma in an older patient, with computed tomography (CT) and magnetic resonance imaging (MRI) characteristics of OM and a literature review. <h3>Materials and Methods</h3> CT was performed with a 64-row multidetector CT (MDCT) scanner (Somatom Sensation 64, Siemens Healthcare, Erlangen, Germany) and magnetic resonance imaging (MRI) was performed with a 3 T MRI unit (Magnetom Spectra, Siemens Healthcare, Erlangen, Germany) with a 16-channel head and neck coil. <h3>Results</h3> The initial panoramic study showed a poorly defined lytic lesion in the left ramus in close proximity to the inferior alveolar canal. CT revealed a hypodense lesion with a thinned out buccal cortex and a disrupted lingual cortex. Axial T1-weighted MRI showed a well-demarcated, low-intensity lesion in the posterior left mandible. An axial T2-weighted sequence displayed a well-defined, hyperintense mass. In a fat-suppressed T2 scheme, the lesion was even more conspicuous. The mass further displayed a high mean apparent diffusion coefficient value of 1.74 × 10^-3 mm²/s. Aneurysmal bone cyst, central hemangioma, odontogenic myxoma, and central giant cell granuloma were considered as differential diagnoses. After histopathologic evaluation, a definitive diagnosis of odontogenic myxoma of the left mandible was made. The lesion was treated with segmental mandibulectomy. The distribution of odontogenic myxoma by age, gender, and imaging modality was studied retrospectively in the literature review. patient age range was 0 to 80 years, and there was a male predilection. Mean ages of female and male patients were 40.5 years and 56.75 years, respectively. The distribution of imaging modalities was 40% for conventional methods, 45% for CBCT/CT and 15% for MRI. <h3>Discussion</h3> In the present study, MRI features, such as the hyperintense signal on T2-weighted images and low-signal intensity on T1-weighted images, were consistent with those of cases reported in the literature. Although CT could delineate the lesion and its extent, MRI was more effective in accurately delineating margins and determining the extent of the tumor for better guidance of the surgical procedure. MRI should, therefore, be considered the imaging modality of choice for diagnosis and margin delineation of OM because this tumor demonstrates a high recurrence rate. All 3 imaging modalities have inherent advantages and disadvantages; however, all of these modalities should be routinely used in the diagnosis of OM. Results of MRI can further help map the margins and greatly aid in resection with clear margins.

Measurement of stapes footplate thickness in otosclerosis by ultra-high-resolution computed tomography

Background Ultra-high-resolution computed tomography (U-HRCT) utilizes a 1024 × 1024 matrix with 0.25-mm section thickness, offering better spatial resolution than conventional multi-detector row CT to detect anatomic data for otologic surgery. Aims We examined stapes footplate thickness using U-HRCT in relation to stapedotomy to predict the difficulty of the surgical procedure. Materials and methods Subjects were 12 otosclerosis patients and 25 controls who underwent diagnostic U-HRCT. A profile curve (Hounsfield units) was used to measure stapes footplate thickness along a perpendicular line across the stapes footplate in a plane parallel to the lateral semicircular canal. Results Footplate thickness was smaller at the midpoint than just before the anterior crus and just after the posterior crus. Interobserver variability was lowest at the midpoint, where foot plate thickness was significantly greater in the affected ear in otosclerosis patients compared with controls (0.60 ± 0.09 mm vs 0.46 ± 0.04 mm; p < .001). Otosclerosis patients were detected using U-HRCT with a high area under the curve. Difficulty in the stapes opening procedure correlated with stapes footplate thickness. Conclusions Footplate thickness on U-HRCT correlated with temporal bone anatomy and corresponded to surgical difficulty. Significance: U-HRCT-derived anatomic data is useful for evaluating the stapes.

Paradoxical embolism after surgery for breast cancer: a case report

BackgroundParadoxical embolism (PDE) presented with concomitant pulmonary embolism (PE) and renal artery embolism (RAE) which occurred to breast cancer patient after breast-conserving therapy, has never been reported.Case presentationA 55-year-old female with breast cancer exhibited unexplained hypoxemia, followed with vomiting, diarrhea, unilateral flank pain and abdominal pain after lumpectomy 12 h. The urgent multi-detector row computed tomography (MDCT) confirmed the diagnosis of PE and RAE. Confusingly, the patient had no history of intracardiac defect, cardiac valvular diseases, atrial fibrillation or other cardiovascular disease and the definite cause was still unclear. However, after 10 days of prompt anticoagulant therapy in ICU, she was discharged in good condition.ConclusionBreast cancer patients after surgery suffering from unexplained hypoxemia, abdominal pain, vomiting and diarrhea should be highly suspicious of PE or RAE, even PDE. Any clinical presentation on these postoperative patients should be given much more attention to make accurate diagnosis and appropriate interventions.

Dynamic contrast-enhanced computed tomography lymphangiography with intranodal injection of water-soluble iodine contrast media in microminipig: imaging protocol and feasibility.

To evaluate the optimal imaging protocol and the feasibility of intranodal dynamic contrast-enhanced computed tomography lymphangiography (DCCTL) in microminipigs. The Committee for Animal Research and Welfare provided university approval. Five female microminipigs underwent DCCTL after inguinal lymph node injection of 0.1mL/kg of iodine contrast media at a rate of 0.3mL/min with three different iodine concentrations: group 1, 75mgI/mL; group 2, 150mgI/mL; and group 3, 300mgI/mL. The CT values of the venous angle, thoracic duct (TD), cisterna chyli, iliac lymphatic duct, and iliac lymph node were measured; increases in CT values pre- to post-contrast were assessed as the contrast-enhanced index (CEI). Multi-detector row CT (MDCT) and volume rendering images showing the highest CEI were qualitatively evaluated. The CEI of all lymphatics peaked at 5-10min. The mean CEI of TD at 10min of group 2 (193.0 HU) and group 3 (201.5 HU) were significantly higher than that of group 1 (70.7 HU) (p = 0.024). The continuity and overall diagnostic acceptability of all lymphatic system components were better in group 3 (3.6 and 3.0, respectively) than group 1 (2.6 and 1.6) and group 2 (3.0 and 2.6) (p = 0.249 and 0.204). The optimal imaging protocol for intranodal DCCTL could be dual-phase imaging at 5 and 10min after the injection of 300mgI/mL iodinated contrast media. DCCTL provided good images of lymphatics and is potentially feasible in clinical settings. • Dynamic contrast-enhanced computed tomography lymphangiography with intranodal injection of water-soluble iodine contrast media showed the highest enhancement of all lymphatics at scan delays of 5 and 10min. • The optimal iodine concentration for intranodal dynamic contrast-enhanced computed tomography lymphangiography might be 300mgI/mL. • Intranodal dynamic contrast-enhanced computed tomography lymphangiography provided good images of all the lymphatic system components and is potentially feasible in clinical settings.

Splenic extramedullary hematopoiesis in dogs is frequently detected on multiphase multidetector-row CT as hypervascular nodules.

Extramedullary hematopoiesis (EMH) is the formation and development of blood cells outside the bone marrow, and in dogs it frequently occurs in the spleen. Although splenic EMH is a relatively common condition, data regarding its appearance in veterinary medicine are lacking. Our aim was to describe different multidetector computed tomographic (MDCT) features of splenic EMH in dogs. In this descriptive retrospective study, dogs with cytological diagnosis of splenic EMH and three-phase MDCT study of the abdomen were included. Multi-detector CT findings recorded were splenomegaly, appearance of the parenchyma, and mean attenuation of the spleen and lesions. Out of 89 dogs included, 55 (62%) presented multifocal nodular aspect, 14 (16%) mass, 12 (13%) diffuse heterogeneous parenchyma, and eight (9%) normal spleen. Most lesions were hyperattenuating to the parenchyma in the arterial (57/89, 64%) and portal (59/89, 66%) phases; whereas in the interstitial phase only 40 of 89 (45%) were hyperattenuating. The mean attenuations of the lesions were higher compared to the values of the adjacent spleen, and the difference of the mean attenuation between the hyperattenuating lesions and the parenchyma was significantly higher in arterial and portal phases than in interstitial phase (P<.0001). The most frequent MDCT aspect of splenic extramedullary hematopoiesis consists of multiple nodules hyperattenuating to the normal spleen, best visualized in the arterial and portal phases.

Preoperative evaluation of vascular morphology and function of living renal donors on multi-detector row CT

Preoperative evaluation of vascular morphology and function of living renal donors on multi-detector row CT

Nonneoplastic Tracheal Abnormalities on CT

Tracheal disorders can create clinical and imaging challenges. They are often misdiagnosed as other pulmonary disorders. Chest radiography has low sensitivity and specificity for proper identification of tracheal disorders. Multidetector-row CT (MDCT) has the inherent advantage of being able to provide high-quality multiplanar reformations, 3D volume-rendered images, virtual bronchoscopy, and minimum intensity projections. These can serve as a roadmap for bronchoscopy or surgical planning. The most important imaging sign of tracheal disease is thickening of the tracheal wall, and the most relevant sign to be evaluated for differential diagnosis is the distribution and appearance of wall thickening. Tracheal abnormalities may be classified based on the tracheal dimensions into increased diameter or decreased diameter to reduce the differential diagnosis. Increased diameter tracheal diseases may be subclassified into diffuse or focal diseases based on the area of involvement, thereby providing a more specific diagnosis.

Multiplatform, Non-Breath-Hold Fast Scanning Protocols: Should We Stop Giving Breath-Hold Instructions for Routine Chest CT? [Formula: see text

We assessed if non-breath-hold (NBH) fast scanning protocol can provide respiratory motion-free images for interpretation of chest computed tomography (CT). In our 2-phase project, we first collected baseline data on frequency of respiratory motion artifacts on breath-hold chest CT in 826 adult patients. The second phase included 62 patients (mean age 66 ± 15 years; 21 females, 41 males) who underwent an NBH chest CT on either single-source (n = 32) or dual-source (n = 30) multidetector-row CT scanners. Clinical indications for chest CT, reason for using NBH CT, scanner type, scan duration, and radiation dose (CT dose index volume, dose length product) were recorded. Two thoracic radiologists (R1 and R2) independently graded respiratory motion artifacts (1 = no respiratory motion artifacts with unrestricted evaluation; 2 = minor motion artifacts limited to one lung lobe or less with good diagnostic quality; 3 = moderate motion artifacts limited to 2 to 3 lung lobes but adequate for clinical diagnosis; 4 = poor evaluability or unevaluable from severe motion artifacts; and 5 = limited quality due to other causes like high noise, beam hardening, or metallic artifacts), and recorded pulmonary and mediastinal findings. Descriptive analyses, Cohen κ test for interobserver agreement, and Student t test were performed for statistical analysis. No NBH chest CT were deemed uninterpretable by either radiologist; most NBH CT (R1-59 of 62, 95%; R2-62 of 62, 100%) had no or minimal motion artifacts. Only 3 of 62 (R1) NBH chest CT had motion artifacts limiting diagnostic evaluation for lungs but not in the mediastinum. Non-breath-hold fast protocol enables acquisition of diagnostic quality chest CT free of respiratory motion artifacts in patients who cannot hold their breath.

Objective evaluation of the relationship between facial expression analysis by the facial action coding system (FACS) and CT/MRI analyses of the facial expression muscles.

There are few reports on the relationship between facial expression formation and mass of the muscle responsible for facial expression. We analyzed the facial expression using facial action coding system (FACS) and examined the muscle mass and characteristics of the facial expression muscles using multi-detector row computed tomography (MDCT) and magnetic resonance imaging (MRI). Moreover, the relation between these was statistically evaluated. Ten healthy women in their 40s (43.4±3.0years, 40-49) were enrolled. The expressive faces were analyzed by facial expression analysis software based on the FACS. The muscle mass and characteristics of the facial expression muscles were investigated using MDCT/MRI. The correlation between an integrated expression intensity value (IEIV) for FACS of the widest possible grin and muscle mass was analyzed. The mean values between the two categorized groups (G-1 and G-2) based on fat infiltration into the muscle were compared. A positive correlation is found between the IEIV and the muscle mass. The IEIV of G-1 is significantly larger than the corresponding value of G-2. Hence, the results indicated that the subjects with high IEIV and expressive face had thicker facial expression muscles and little fat infiltration into the muscles. Our objective imaging diagnostic study using FACS, MDCT, and MRI corroborated the anti-aging medical science about the facial expression muscles related to youthful facial appearance. The results of this research could contribute to the elucidation of the mechanisms involved in the facial aging process and to the development of cosmetology.

Injuries of the isolated larynx-hyoid complex in post-mortem computed tomography (PMCT) and post-mortem fine preparation (PMFP) - a comparison of 54 forensic cases

ObjectivesTo assess the diagnostic accuracy (ACC) of post-mortem computed tomography (PMCT) for fractures of the isolated larynx-hyoid complex (LHC) in comparison to post-mortem fine preparation (PMFP).MethodsThis monocentric prospective study enclosed 54 LHCs that were extracted during autopsy, fixed in formalin, and underwent a PMCT scan (64-row multidetector CT, helical pitch). Two radiologists independently analyzed the LHC scans for image quality (IQ) and fractures (4-point Likert scales). A specialized forensic preparator dissected the specimens under the stereomicroscope. The PMFP results were standardized documented, and used as the standard of reference for the comparison to PMCT.ResultsThe PMCT-IQ of 95% of the LHC images was rated as good or excellent. IQ was decreased by decay, incisions during autopsy, and separation of the hyoid from the cartilaginous components in 7, 3, and 12 specimens, respectively. PMFP detected 119 fractures in 34 LHCs (63.0%). PMCT identified 91 fractures in 32 specimens (59.3%). PMFP and PMCT significantly agreed concerning the location (Cohen’s κ = 0.762; p < 0.001) and the degree of dislocation (κ = 0.689; p < 0.001) of the fractures. Comparing PMCT to PMFP resulted in a sensitivity of 88.2%, a specificity of 90.0%, and an ACC of 88.9% for the LHC. The ACCs for the hyoid, thyroid, and cricoid were 94.4%, 87.0%, and 81.5%, respectively. PMCT procedure was significantly faster than PMFP (28.9 ± 4.1 min vs. 208.2 ± 32.5 min; p < 0,001).ConclusionsPMCT can detect distinct injuries of the isolated LHC and may promptly confirm violence against the neck as cause of death. PMFP outmatches PMCT in the detection of decent injuries like tears of the cricoid cartilage.Key Points• Post-mortem computed tomography is able to assess fractures of the larynx-hyoid complex.• Prospective monocentric in vitro study showed that post-mortem computed tomography of the larynx-hyoid complex is faster than post-mortem fine preparation.• Post-mortem computed tomography can confirm violence against the neck as cause of death.

FEATURE TRACKING MULTI-DETECTOR ROW COMPUTED TOMOGRAPHY-DERIVED LEFT VENTRICULAR GLOBAL LONGITUDINAL STRAIN IN A LARGE COHORT OF TAVR PATIENTS AND ASSOCIATION WITH ALL-CAUSE MORTALITY

Recent developments in multidetector row computed tomography (MDCT) permits assessment of left ventricular global longitudinal strain (LV GLS) with feature tracking (FT) and may play an important role in the risk-stratification of patients undergoing transcatheter aortic valve replacement (TAVR).