Multidetector Computed Tomography Scans Research Articles

Diagnostic Accuracy of Hyperdense Artery Sign in Early Detection of Middle Cerebral Artery Infarction: A Cross-Sectional Validation Study

Background Hyperdense middle cerebral artery sign (HMCAS) on a non-enhanced multidetector computed tomography (MDCT) scan is considered an important radiological marker in detecting acute arterial thrombotic occlusion, and it is one of the earliest signs of ischemic cerebrovascular accident (CVA). This finding has been observed within 90 min of symptom onset. Modern approaches to patients with cerebral infarction emphasize early diagnosis and management. Purpose To determine the diagnostic accuracy of hyperdense artery signs in early detection of middle cerebral artery (MCA) infarction on non-contrast-enhanced MDCT scan using Magnetic Resonance Angiography (MRA) within 24 h as the gold standard for definitive diagnosis. Method A total of 140 patients aged 35–70 years, referred to the radiology department of Aga Khan University Hospital with clinical suspicion of acute cerebral infarction, were included. After clinical suspicion of acute infarction, the patient underwent an initial complete MDCT scan of the brain, which was performed using Aquilion ONE 640 slice MDCT (Toshiba Medical Systems, Japan). Consultant radiologists, with a minimum of 5 years of experience in MDCT brain imaging, interpreted the images. Follow-up examination with MRA within 24 h was performed to confirm the diagnosis of MCA infarction. Results Overall sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of HMCAS in the early detection of MCA infarction on non-contrast-enhanced MDCT scan using MRA as the gold standard for definitive diagnosis was 96.20%, 93.44%, 95.0%, 95.0%, and 95.0%, respectively. Conclusion This study concluded that the diagnostic accuracy of hyperdense artery signs in the early detection of MCA infarction on non-contrast-enhanced MDCT scans is very high.

Role of Multidetector Computed Tomography in Differentiation of Benign and Malignant Cavitary Lung Lesions With a Histopathological Correlation: A Retrospective Cross-Sectional Study.

Introduction Cavitary lung disease has a wide range of differential diagnoses, which include both benign and malignant lesions. Imaging differentiation of benign from malignant cavitary lesions has always been a challenge due to overlapping imaging findings. The present study describes the most accurate multidetector computed tomography (MDCT) findings that could help in differentiating benign from malignant conditions in correlation with the histopathological reports. Methods This retrospective study was carried out on diagnosed cases of cavitary lung lesions on MDCTfrom January 2022 to February 2023. We evaluated the number of cavitary lung lesions, their location with respect to lung segment/lobe, the maximum diameter of the largest lesion, the maximum wall thickness of the largest cavity, and additional findings associated with these lesions. Measurements of the maximum wall thickness were plotted on a graph. Statistical analysis was done, and a receiver operating characteristic curve (ROC) was calculated to find the accurate cut-off wall thickness for malignant and non-malignant lesions.These findings were then correlated with the histopathological report. Results A review of the MDCT scans of 47 patients was done; 30 (63.8%) of those were male with a mean age of 47.93±14.68 (SD) years while 17 (36.2%) were female with a mean age of 52.53 ±18.38 (SD) years. Out of 47 patients, 27 (57.4%) had benign lesions and 20 (42.5%) had malignant lesions. Significant differences (p<0.05) were found between benign and malignant lesions while comparing the averages of maximum wall thickness (8.1 mm and 14.5 mm, respectively) and the irregular inner margin of the largest cavitary lesions. The presence of consolidation and centrilobular nodules correlated significantly (p<0.05) with the benign nature of cavitary lung lesions. The maximum cut-off wall thickness was <6 mm and >17 mm for the differentiation of benign from malignant lung lesions, respectively. Conclusions The maximum wall thickness and irregular inner margin of cavitary lung lesions was a good indicator for the differentiation of benign and malignant etiologies on MDCTwhile consolidation and centrilobular nodules favoured the benign etiology more.

A ligament to identify the inferior limit of dissection in minimally invasive surgery for inguinal hernia

Background: Minimally invasive surgery has recently become the approach of choice for surgeons for inguinal hernia repair. Subsequent to excellent visualisation of the preperitoneal space by high definition and 4K systems during laparoscopy and robotic surgery, as well as increasing use of multi detector CT scans to visualise abdomen, our knowledge of the anatomy of the posterior view of inguinal region has been enhanced. However, recurrence after surgery for groin hernia continues to be an issue during its learning curve especially for laparoscopic repair. One cause for recurrence is the infolding of the mesh after its placement in the preperitoneal space. A reason for this is inadequate dissection of the peritoneal fold especially inferomedially. The peritoneum has to be dissected inferomedially till the point where the vas deferens turns medially. During the course of a randomised study done to compare Transabdominal preperitoneal mesh repair with Totally extraperitoneal mesh repair for Inguinal hernia, a structure was seen passing from the medial aspect of the vas deferens where it turned medially Methods: Prospective analysis of 106 consecutive patients who underwent laparoscopic inguinal hernia was done to identify the presence of such a ligament. Results: This study demonstrates the existence of a ligamentous structure from the vas deferens to the posterior lamina of subparietal layer of peritoneal space at the site where the vas turns medially. Conclusions: Identification and division of this ligament will help to ensure complete dissection of the peritoneum inferiorly as well as creaseless placement of mesh thus preventing recurrence.

Weak to no correlation between quantitative high-resolution computed tomography metrics and lung function change in fibrotic diseases.

Identifying systemic sclerosis (SSc) and idiopathic pulmonary fibrosis (IPF) patients at risk of more rapid forced vital capacity (FVC) decline could improve trial design. The purpose of the present study was to explore the prognostic value of quantitative high-resolution computed tomography (HRCT) metrics derived by Imbio lung texture analysis (LTA) tool in predicting FVC slope. This retrospective study used data from patients who were not treated with investigational drugs with and without background antifibrotic therapies in tocilizumab phase 3 SSc, lebrikizumab phase 2 IPF, and zinpentraxin alfa phase 2 IPF studies conducted from 2015 to 2021. Controlled HRCT axial volumetric multidetector computed tomography scans were evaluated using the Imbio LTA tool. Associations between HRCT metrics and FVC slope were assessed through the Spearman correlation coefficient and adjusted R2 in a linear regression model adjusted by demographics and baseline clinical characteristics. A total of 271 SSc and IPF patients were analysed. Correlation coefficients of highest magnitude were observed in the SSc study between the extent of ground glass, normal volume, quantification of interstitial lung disease, reticular pattern, and FVC slope (-0.25, 0.28, -0.28, and -0.33, respectively), while the correlation coefficients observed in IPF studies were in general <0.2. The incremental prognostic value of the baseline HRCT metrics was marginal after adjusting baseline characteristics and was inconsistent across study arms. Data from the SSc and IPF studies suggested weak to no and inconsistent correlation between quantitative HRCT metrics derived by the Imbio LTA tool and FVC slope in the studied SSc and IPF population.

Vascular Variations and Incidental Pathologies in Potential Living Renal Donors Using 160-Slice Multidetector Computed Tomography Angiography.

The aim of the study is to evaluate the vascular variations and incidental pathologies in potential living renal donors using 160-slice multidetector computed tomography (MDCT) angiography. This is an observational study conducted at the Department of Radiology from January 2017 to May 2022. In this study, we performed retrospective data analysis of 61 CT renal angiograms, totaling 122 kidneys of potential renal donors, using a Toshiba 160 slice MDCT scanner with a four-phase CT image acquisition protocol, performed for pre-transplant workup. All patients had normal renal functions. Of our 61 patients, 34 (55.7%) were male and 27 (44.3%) were female, and their mean age was 31.2 ± 9.4 years. We have found 31 (50.8%) variations in the right renal arteries and 21 (34.4%) in the left renal arteries. Of these patients, 13 had bilateral renal arterial variations. The late confluence of the renal vein was found in 3.3% of males, multiple right renal veins in 7 (11.5%), and left renal veins in 2 (3.3%). By distributing the data according to gender, we noticed more diversity in the renal vessels of male patients. Left renal artery variations were more frequent in males (16, 76.2%) than in females (5, 23.8%), and they were statistically significant (p=0.02). Likewise, variations in the right renal arteries were also more frequently found in males (19, 61.3%) as compared to females (12, 38.7%). Right renal vein variations were more common in males (9, 81.8%) as compared to females (2, 18.2%) (p=0.05). Frequent renal vascular variations and incidental pathologies in potential living donors were found by MDCT examination, and these vascular variations should be analyzed before renal transplant.

Role of MDCT neck in evaluation of neck masses: Our experience

A mass in the neck in adults is a common entity that we customarily encounter in our clinical practice. Diagnosis of these neck masses can be challenging owing to the intricate anatomy and physiology, with a myriad of presenting complaints. Neck masses can be due to multiple causes classified as congenital (eg cystic hygroma), lymphadenopathy, inflammatory or neoplastic (malignant or benign). Various imaging modalities have been applied for the evaluation such as plain x-rays, contrast studies such as lymphogram, xerography and oesophagogram etc. However, these are neither sensitive nor specific in diagnosing the aetiology of neck masses. CT being non-invasive and non-operator dependent depicts excellent quantification of tissue attenuation coefficients and is exceedingly useful in defining both the osseous and soft-tissue extent of the lesion. With the upcoming of newer generation Multidetector CT Scanners (MDCT) have made tremendous improvements in scanning time, tissue resolution and quality of three dimensional (3D) reconstructions. The aim of this study is to evaluate the role of MDCT in neck masses.

Automated Opportunistic Trabecular Volumetric Bone Mineral Density Extraction Outperforms Manual Measurements for the Prediction of Vertebral Fractures in Routine CT

Opportunistic osteoporosis screening using multidetector CT-scans (MDCT) and convolutional neural network (CNN)-derived segmentations of the spine to generate volumetric bone mineral density (vBMD) bears the potential to improve incidental osteoporotic vertebral fracture (VF) prediction. However, the performance compared to the established manual opportunistic vBMD measures remains unclear. Hence, we investigated patients with a routine MDCT of the spine who had developed a new osteoporotic incidental VF and frequency matched to patients without incidental VFs as assessed on follow-up MDCT images after 1.5 years. Automated vBMD was generated using CNN-generated segmentation masks and asynchronous calibration. Additionally, manual vBMD was sampled by two radiologists. Automated vBMD measurements in patients with incidental VFs at 1.5-years follow-up (n = 53) were significantly lower compared to patients without incidental VFs (n = 104) (83.6 ± 29.4 mg/cm3 vs. 102.1 ± 27.7 mg/cm3, p &lt; 0.001). This comparison was not significant for manually assessed vBMD (99.2 ± 37.6 mg/cm3 vs. 107.9 ± 33.9 mg/cm3, p = 0.30). When adjusting for age and sex, both automated and manual vBMD measurements were significantly associated with incidental VFs at 1.5-year follow-up, however, the associations were stronger for automated measurements (β = −0.32; 95% confidence interval (CI): −20.10, 4.35; p &lt; 0.001) compared to manual measurements (β = −0.15; 95% CI: −11.16, 5.16; p &lt; 0.03). In conclusion, automated opportunistic measurements are feasible and can be useful for bone mineral density assessment in clinical routine.

The importance of chest CT severity score and lung CT patterns in risk assessment in COVID-19-associated pneumonia: a comparative study.

Chest computed tomography (CT) is suitable to assess morphological changes in the lungs. Chest CT scoring systems (CCTS) have been developed and use in order to quantify the severity of pulmonary involvement in COVID-19. CCTS has also been correlated with clinical outcomes. Here we wished to use a validated, relatively simple CTSS to assess chest CT patterns and to correlate CTSS with clinical outcomes in COVID-19. Altogether 227 COVID-19 cases underwent chest CT scanning using a 128 multi-detector CT scanner (SOMATOM Go Top, Siemens Healthineers, Germany). Specific pathological features, such as ground-glass opacity (GGO), crazy-paving pattern, consolidation, fibrosis, subpleural lines, pleural effusion, lymphadenopathy and pulmonary embolism were evaluated. CTSS developed by Pan et al. (CTSS-Pan) was applied. CTSS and specific pathologies were correlated with demographic, clinical and laboratory data, A-DROP scores, as well as outcome measures. We compared CTSS-Pan to two other CT scoring systems. The mean CTSS-Pan in the 227 COVID-19 patients was 14.6 ± 6.7. The need for ICU admission (p < 0.001) and death (p < 0.001) were significantly associated with higher CTSS. With respect to chest CT patterns, crazy-paving pattern was significantly associated with ICU admission. Subpleural lines exerted significant inverse associations with ICU admission and ventilation. Lymphadenopathy was associated with all three outcome parameters. Pulmonary embolism led to ICU admission. In the ROC analysis, CTSS>18.5 significantly predicted admission to ICU (p = 0.026) and CTSS>19.5 was the cutoff for increased mortality (p < 0.001). CTSS-Pan and the two other CTSS systems exerted similar performance. With respect to clinical outcomes, CTSS-Pan might have the best performance. CTSS may be suitable to assess severity and prognosis of COVID-19-associated pneumonia. CTSS and specific chest CT patterns may predict the need for ventilation, as well as mortality in COVID-19. This can help the physician to guide treatment strategies in COVID-19, as well as other pulmonary infections.

AI-based CT Body Composition Identifies Myosteatosis as Key Mortality Predictor in Asymptomatic Adults.

Background Body composition data have been limited to adults with disease or older age. The prognostic impact in otherwise asymptomatic adults is unclear. Purpose To use artificial intelligence-based body composition metrics from routine abdominal CT scans in asymptomatic adults to clarify the association between obesity, liver steatosis, myopenia, and myosteatosis and the risk of mortality. Materials and Methods In this retrospective single-center study, consecutive adult outpatients undergoing routine colorectal cancer screening from April 2004 to December 2016 were included. Using a U-Net algorithm, the following body composition metrics were extracted from low-dose, noncontrast, supine multidetector abdominal CT scans: total muscle area, muscle density, subcutaneous and visceral fat area, and volumetric liver density. Abnormal body composition was defined by the presence of liver steatosis, obesity, muscle fatty infiltration (myosteatosis), and/or low muscle mass (myopenia). The incidence of death and major adverse cardiovascular events were recorded during a median follow-up of 8.8 years. Multivariable analyses were performed accounting for age, sex, smoking status, myosteatosis, liver steatosis, myopenia, type 2 diabetes, obesity, visceral fat, and history of cardiovascular events. Results Overall, 8982 consecutive outpatients (mean age, 57 years ± 8 [SD]; 5008 female, 3974 male) were included. Abnormal body composition was found in 86% (434 of 507) of patients who died during follow-up. Myosteatosis was found in 278 of 507 patients (55%) who died (15.5% absolute risk at 10 years). Myosteatosis, obesity, liver steatosis, and myopenia were associated with increased mortality risk (hazard ratio [HR]: 4.33 [95% CI: 3.63, 5.16], 1.27 [95% CI: 1.06, 1.53], 1.86 [95% CI: 1.56, 2.21], and 1.75 [95% CI: 1.43, 2.14], respectively). In 8303 patients (excluding 679 patients without complete data), after multivariable adjustment, myosteatosis remained associated with increased mortality risk (HR, 1.89 [95% CI: 1.52, 2.35]; P < .001). Conclusion Artificial intelligence-based profiling of body composition from routine abdominal CT scans identified myosteatosis as a key predictor of mortality risk in asymptomatic adults. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Tong and Magudia in this issue.

A prospective evaluation of computerized tomography scan findings in blunt abdominal trauma

Background and objective: Evaluating patients with blunt abdominal trauma remains one of the most challenging aspects of acute trauma care. CT scan of abdomen remains the standard imaging modality for evaluation of abdominal trauma cases. The aim of this study is to evaluate CT scan findings in blunt abdominal trauma victims with respect to solid organ injuries, hollow viscus injuries, associated thoracic and abdominal wall injuries, associated hemoperitoneum, cause of injury and type of management. Methods: A cross-sectional study was conducted among 96 hemodynamically stable patients with history of blunt abdominal trauma who underwent CT scan examination in Rozh-halat Emergency Hospital from June 2021-January 2022; using a 64 multi-detector helical slice CT scanner. Data analysis were performed on patient’s demographics, mode and type of injury, CT scan findings and severity scorings, associated injuries and type of management. Results: The mean age of enrolled cases was 28.6 ± 18.6 ranged from 4-70 years. About two third (63.5%) were males and one third were females (36.5%). The most common cause of trauma was road traffic accident (64% of cases). Out of 96 trauma cases; 87.5% of patients had positive CT findings of which 50% had hemoperitoneum, 21.9% had pneumoperitoneum, 66.7% had no hallow viscous involvement, while 33.2% had hollow viscus involvement. One third of cases had associated abdominal wall injury. 56.4% of patients had multiple organ injury. Regarding solid organ injury; 66.7% of cases had spleen injury, (36.5%) had liver injury, Pancreas was involved in 12.5% of cases. RT&amp; LT – kidneys showed grade 2 injury in (9.4%) &amp; (6.3 %) respectively. Half of patients with positive CT scan findings had no lower chest injury findings. This study showed that 43.8% of cases were managed conservatively, 45.9% underwent laparotomy, the incidental finding of intra-operative hemoperitoneum which was negative in CT scan was only 1%. Conclusion: CT imaging is the diagnostic tool of choice for the evaluation of blunt abdominal trauma in haemo-dynamically stable patients as it can assist in detecting and evaluating other co-existing injuries such as lower thoracic, pelvic and spine injuries apart from its main role in accurate identification of intra -abdominal injuries and associated bleeding.

Baseline CT-Based Risk Factors for Atrioventricular Block after Surgical AVR

We aimed to evaluate the impact of membranous interventricular septum (MIS) length and calcifications of the native aortic valve (AV), via preoperative multidetector computed tomography (MDCT) scan, on postoperative atrioventricular block III (AVB/AVB III) and permanent pacemaker implantation in surgical aortic valve replacement (SAVR). We retrospectively analyzed preoperative contrast-enhanced MDCT scans and procedural outcomes of patients affected by AV stenosis who underwent SAVR at our center (June 2016-December 2019). The study population was divided into two groups (AVB and non-AVB), and variables were compared with a Mann-Whitney's U-test or chi-square test. Data were further analyzed using point biserial correlation and logistic regression. A total of 155 (38% female) patients (mean age of 71.2 ± 6 years) were enrolled in our study: conventional stented bioprosthesis (N = 99) and sutureless prosthesis (N = 56) were implanted. A postoperative AVB III was observed in 11 patients (7.1%). AVB patients had significant greater calcifications in left coronary cusp (LCC) -AV (non-AVB = 181.0 mm3 [82.7-316.9] vs. AVB = 424.8 mm3 [115.9-563.2], p = 0.044), LCC left ventricular outflow tract (LVOT) (non-AVB = 2.1 mm3 [0-20.1] vs. AVB = 26.0 mm3 [0.1-138.0], p = 0.048), right coronary cusp (RCC) -LVOT (non-AVB = 0 mm3 [0-3.5] vs. AVB = 2.8 mm3 [0-29.0], p = 0.039), and consequently in total LVOT (non-AVB = 2.1 mm3 [0-20.1] vs. AVB = 26.0 mm3 [0.1-138.0], p = 0.02), while their MIS was significantly shorter than in non-AVB patients (non-AVB = 11.3 mm [9.9-13.4] vs. AVB = 9.44 mm [6.98-10.5]; p=0.014)). Partially, these group differences correlated positively (LCC -AV, r = 0.201, p = 0.012; RCC -LVOT, r = 0.283, p ≤ 0.001) or negatively (MIS length, r = -0.202, p = 0.008) with new-onset AVB III. We recommend including an MDCT in preoperative diagnostic testing for all patients undergoing surgical AVR for further risk stratification.

Assessment of Anatomical Variation of Styloid Process in Multidetector Computed Tomography

Objective: This study aimed to assess the anatomical variation of the styloid process of Nepalese individuals by using multi-detector computed tomography scans. It was carried out to establish the baseline for the normal length of the styloid process and to compare the variability of styloid process measurement between different age group and gender. Materials and methods: This quantitative, cross-sectional was performed in the Department of Radiology and Imaging, Tribhuvan University Teaching Hospital. Imaging data were collected over the period of January to April 2021 with the total number of 153 individuals. The age and gender of the individuals were noted. The measurement was done in the Multiplanar Reconstruction (MPR) coronal sections of Head and Neck, PNS and Cerebral Angiography. Various Styloid Process (SP) morphology parameters like RLSP, RGSP, LLSP, LGSP, Right Elongation Type, Right Calcification Type, Left Elongation Type, and Left Calcification Type was measured. Results: The measurement of the length of SP was found to be 3.06±0.72 cm (ranged 1.80-5.54 cm) in right SP while that of left SP was 3.08±0.72 cm (ranged 1.45-5.69 cm). The gap between the SP and the calcification pattern was found to be 0.51±0.30 cm (ranged 0.08-1.20 cm) in right SP while that of left SP was 0.63±0.43 cm (ranged 0.08- 1.97cm). Similarly, there was a statistical significant difference between the RLSP-RGSP and LLSP-LGSP. The length of styloid process was found to be higher among male than in female. But there was no statistical significant difference between male and female in the SP measurement. The series of elongation patterns were found to be normal SP, followed by elongated, distant elongated, pseudoarticulated, and segmented SP. The series of calcification patterns were found to be calcified SP, followed by nodular, partial, and outlined SP. Conclusion: In this study, the valuable information regarding anatomical length and variation of styloid process with respect to age and gender among the Nepalese individuals was found. 3D CT reconstruction is a gold standard investigation that helps in studying the relation of the SP with surrounding structures.

ULTRASONOGRAPHY COMPARED TO CT SCAN FOR THE ASSESEMENT OF SEVERITY IN PATIENTS WITH COVID-19 PNEUMONIA: EXPERIENCE OF A MAJOR TERTIARY REFERRAL HOSPITAL IN INDIA

A study was conducted to assess the severity of COVID-19 pneumonia by ultrasonography compared to computed tomography. 50 patients, older than 18 years, referred to a major territory care centre in India between June and December 2021 with any two of the three criteria: fever, Spo2&lt;94% on room air, and shortness of breath were studied. Patients proven to have COVID-19 pneumonia with either RT-PCR/RAT or Computed tomography scan were excluded from the study. Lung ultrasound was performed by two experienced physicians using a portable ultrasound device. A modied Lung Ultrasound Score for COVID-19 was compared with a computed tomography scan performed using a single inspiratory phase in a commercial multi-detector computed tomography scanner. Results: The correlation coefcient between the lung ultrasound score and the computed tomography severity score (r) was 0.79 (strong correlation) with a p value &lt;0.00001 (signicant as p value &lt;0.05). In patients with moderate to severe disease, the correlation was stronger. Conclusions: Our study showed that there is a good correlation between the lung ultrasound score and Computed tomography severity score. Lung ultrasound may help as an alternative method for diagnosing and isolating COVID-19 pneumonia patients during the peaks of the pandemic. Lung ultrasound score exhibited similar accuracy compared with chest computed tomography in the detection of lung abnormalities in COVID-19 patients.

Assessment of Utility of Computed Tomography Pulmonary Angiography in Pulmonary Embolism

Background: Among all the available diagnostic tools, computed tomography (CT) is the preferred diagnostic tool for clinically suspected pulmonary embolism (PE) cases. Further, with the development of multi–detector row CT (MDCT) technology, previous limitations of CT have been overcome effectively. For patients with clinical suspicion of PE, MDCT pulmonary angiography has become the first line of modality for the diagnosis. Aims and Objectives: To evaluate various common observations of CT pulmonary angiography (CTPA) in suspected cases of PE that could accurately determine the choice of management. Materials and Methods: Fifty patients with clinically suspected PE referred to the department of Radiodiagnosis for CTPA from various departments were studied in the cross-sectional study. CT images were obtained with a SIEMENS 64-slice multi-detector CT scanner (somatom definition AS). Images were reconstructed into 3D, axial, coronal, sagittal maximum intensity projection sections, and volume rendering techniques. The axial as well as reformatted coronal and sagittal images were evaluated. Results: The incidence of PE was 52%. The incidence of PE was highest in patients older than 60 years (30.8%) and males (30.3%; p=0.662). The most common symptoms evoking a suspicion of pulmonary embolism were dyspnea (69.2%), followed by chest pain (15.4%), cough (11.5%), and hemoptysis (3.8%). Out of 26 patients who had PE, 61.5% had right ventricular enlargement. DVT (23.1%) was the most common past history. The majority of the patients had thrombus in the right main pulmonary artery (21.1 %), followed by the left main pulmonary artery (19.3 %). Conclusion: In clinically suspected cases of PE, MDCT pulmonary angiography was a useful diagnostic tool. CTPA is the modality of choice for its rapid, minimally invasive, and well-tolerated nature.

Abstract OT1-12-03: Precision breast conserving surgery with the guidance of localization combined with multidetector CT 3-dimensional image reconstruction: a single center, prospective, cohort study

Abstract Introduction: Precision breast conserving surgery (PBCS) requires doctors to precisely remove the tumor while preserving as much normal tissue as possible. The aims of this study were to determine whether wire-guided localization (WGL) combined with multidetector CT (MDCT) guided 3D reconstruction could guide PBCS. Methods: From 2020 to 2022, 31 patients with unifocal breast cancer were enrolled for PBCS guided by WGL combined with MDCT guided 3D reconstruction. Surrounded WGL was performed under local anesthesia, followed by an immediate contrast enhanced MDCT scan. PBCS guided by MDCT guided 3D reconstruction was performed one day after the localization. Women who underwent palpation guided BCS were included as control, and logistic regression analysis was applied. Results: PBCS were performed in 31 patients. The mean tumor size in US was 19.48±5.86mm (9-32mm). Compare with control group, a smaller specimen diameter was observed in PBCS group (P=0.005), and the rate of the largest margin greater than or equal to 20mm were significantly lower (P=0.004). The operation time of PBCS was shortened (P=0.046). Moreover, PBCS does not affect the reoperation rate (P=0.514) or the rate of positive margins (P=0.660). Conclusion: For patients with unifocal breast cancer, WGL combined with MDCT guided 3D reconstruction could guide PBCS without affecting the safety. Table 1. Baseline characteristics of patients in PBCS group and control group. BMI, body mass index; US, ultrasound; HR, hormone receptor. Table 2. Surgical outcomes of patients in PBCS group and control group. Citation Format: Yiqin Xia, Da Cao, Lili Yang, Mingjie Zheng, Miaomiao Weng, Ke Shi, Ruoxi Wang, Meng Zhao, Hui Xie, Shui Wang. Precision breast conserving surgery with the guidance of localization combined with multidetector CT 3-dimensional image reconstruction: a single center, prospective, cohort study [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr OT1-12-03.

Can multidetector CT replace MRI for evaluating mesorectal fascia in rectal cancer?

Colorectal cancer is the fourth leading cause of cancer mortality. This study aims to compare the clinical outcomes of multidetector computed tomography (MDCT) with magnetic resonance imaging (MRI) for assessing mesorectal fascia (MRF) in patients with rectal cancer. This research was a cross-sectional study of 60 patients with rectal cancer referred to two centers in Isfahan, Al-Zahra, and Seyed-al-Shohada hospitals. Considered parameters included sex, tumoral location, nodal involvement, as well as tumoral description. To assess the invasion of MRF in rectal cancer, researchers used MRI, axial MDCT, and multiplanar reconstruction CT scan (MPRCT). Sensitivity, specificity, and techniques' positive and negative predictive values were measured. Also, to assess the statistical associations, the Kappa coefficient was used. There was no significant association between axial MDCT and MRI reports regarding MRF involvement (P>0.05). However, a statistical association was determined between the reports of multiplanar reconstruction CT (MPRCT) and MRI (P< 0.01, kappa=0.44). In addition, the association between MPRCT and MRI reports was statistically significant in patients with wall thickening and negative nodal involvement (Kappa = 0.699, P = 0.001). On the other hand, there was more agreement between MPRCT and MRI reports in patients with tumors in the middle or upper rectum. The association between MRI and MPRCT reports regarding MRF involvement was statistically significant in patients with wall thickening and negative nodal involvement in the upper and middle rectum. Consequently, it is possible to replace MRI with the MPRCT method for assessing MRF in some patients.

Construction of a computational MDCT model for simulations of the detector signals

ObjectiveTo develop a computational model of a multi-detector CT scanner (MDCT), which could be used to simulate the signal of each detector element in the MDCT by using the Monte Carlo method. MethodsThe CT scanner was modelled, including the X-ray source, the bowtie filter, the collimator, the couch and the detector panel. Under a general scanning condition, the signal in each detector element was simulated based on the model by using the MCNPX code. Both the energy spectra at different tube voltages and energy deposition in the detector panel at different collimations were simulated to test the robustness of the MDCT model built in this study. Furthermore, the simulated signals in each detector element were compared with their recorded signals. The accuracies were evaluated by the relative root mean square error (RRMSE) and the structural similarity (SSIM) for each detector element and the whole detector panel, respectively. ResultsThe simulated energy spectra before and after passing through the phantom and simulated energy deposition in the detector panel were rational. In the scan range from the apex of lung to pubic symphysis, the RRMSE of the 18 axial projections ranged from 0.02 to 0.17, with an average of 0.08. And the SSIMs were calculated to be 0.979 and 0.976 for projections with the largest peak signal and the smallest peak signal, respectively. ConclusionsThe computational model of the MDCT developed in this study is accurate and successful, it is helpful for further accurate simulations of the radiation dose and image quality of the MDCT.

Multidetector computed tomography angiography study of the renal arterial vasculature anatomy and its variations in a Bulgarian adult population.

Renal arterial anatomy has a great clinical importance during surgical and endovascular procedures. However, comprehensive data on renal arterial variations in the Bulgarian population has not yet been provided. The aim of this study was to conduct a detailed research about the normal anatomy and variations of the renal arteries in the Bulgarian population. Five hundred sixty-one patients underwent contrast-enhanced multidetector computed tomography scans for the period 2016-2021. The images were retrospectively reviewed. Number, branching pattern, origin level and course of the renal arteries were noted. Data were categorized on the basis of laterality, gender and symmetry. Only 46.3% of the patients exhibited normal renal arterial anatomy. Variations were observed in 301 patients (53.7%). The most common variant was the presence of accessory renal arteries (ARA), discovered in 41.2% of the subjects. There was no significant difference based on gender and laterality (p > 0.05). Hilar ARA (72.6%) were significantly more common than polar ARA (p < 0.001). The most common origin location of the main renal arteries and ARA was the aorta, followed by the common iliac arteries. Early division was observed in 21.7% of the patients, significantly more common on the right. Precaval course was found in 0.5% of the right main renal arteries and in 30% of ARA and the difference was significant (p < 0.001). These results show novel insight into the prevalence of renal arterial variations in the Bulgarian population. Anatomic renal vasculature variants are common therefore awareness is crucial for the success of surgical and interventional procedures.

A novel transit-time flow metric, diastolic resistance index, detects subcritical anastomotic stenosis in coronary artery bypass grafting.

Transit time flow measurement (TTFM) can detect critical anastomotic stenosis during coronary artery bypass grafting. However, the identification of subcritical stenosis remains challenging. We hypothesized that diastolic resistance index (DRI), a novel TTFM metric, is more effective in evaluating subcritical stenosis than the currently available TTFM metrics. DRI is used to measure changes in the diastolic versus systolic resistance of distal anastomosis. A total of 123 coronary bypass anastomoses in 35 patients were prospectively analyzed. During coronary artery bypass grafting, the mean graft flow (Qmean), pulsatility index, and diastolic filling were obtained. DRI was calculated using the intraoperative recordings of TTFM and arterial pressure. Postoperatively, stenosis of anastomoses was categorized into successful (<50%), subcritical (50%-74%), and critical (≥75%) via multidetector computed tomography scan. In total, 93 (76%), 13 (10%), and 17 (14%) anastomoses were graded as successful, subcritical, and critical, respectively. DRI and diastolic filling could distinguish subcritical from successful anastomoses (P<.01 and<.01, respectively), whereas Qmean and pulsatility index could not (P=.12 and .39, respectively). The receiver operating characteristic curves were established to evaluate the diagnostic ability for detecting ≥50% stenosis. In left anterior descending artery grafting (n=55), DRI had the highest area under the curve (0.91), followed by diastolic filling (0.87), Qmean (0.74), and pulsatility index (0.65). DRI and diastolic filling had a reliable diagnostic ability for detecting ≥50% stenosis during coronary artery bypass grafting. In left anterior descending artery grafting, DRI had a more satisfactory detection capability than other TTFM metrics.

Role of computed tomography imaging in the diagnosis of blunt and penetrating abdominal trauma injuries

Background: The present study was conducted with the primary aim of evaluating the role of computed tomography imaging in the assessment of blunt abdominal trauma (BAT) and penetrating abdominal trauma injuries. Methods: This prospective study comprised 53 patients with BAT and PAT injuries referred from the emergency department to the department of radio-diagnosis for ultrasonography and CT. Multidetector computed tomography scans were performed on GE Bright Speed Elite 16 slice CT Scanner. The various injuries seen on the CT images were grouped and examined based on the injury site and the organs involved. Results: The majority of the study subjects, i.e., 17/53 (32.08%) belonged age group of 20-30 yrs. Out of the 53 study subjects, 48 had BAT and 5 had PAT. The majority of study subjects who had BAT, i.e., 26/48 RTA, was the cause of trauma, and 5 out of 5 who had PAT assault was the cause of trauma. The most common organ injured was the spleen (18), followed by the liver (17), bowel (15), Anterior abdominal wall (6), pancreas (1), Kidney (1), Uterus (2), Multiple organs (1) and Hemoperitoneum without solid organ injury (1). CT showed 100% accuracy in the diagnosis of abdominal organ injuries. Conclusions: CT imaging plays a pivotal role in the rapid identification of life-threatening injuries and is helpful for prompt initiation of appropriate care, which leads to an increase in the chance of survival of patients with BAT and PAT injuries.