Multidetector-row CT angiography of the aorta and visceral arteries

Investigation of abdominal artery delineation by photon-counting detector CT

OBJECTIVES

To evaluate the ability of 50-keV virtual monoenergetic images (VMI) to depict abdominal arteries in abdominal CT angiography (CTA) compared with 70-keV VMI with photon-counting detector CT (PCD-CT).

METHODS

Fifty consecutive patients who underwent multiphase abdominal scans between March and April 2023 were included. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were quantitatively assessed for the abdominal aorta (AA), celiac artery (CeA), superior mesenteric artery (SMA), renal artery (RA), and right hepatic artery (RHA) at both 50- and 70-keV VMI. In addition, 3D images from CTA were analyzed to measure arterial lengths and evaluate the visualization of distal branches.

RESULTS

Significantly higher SNR and CNR were observed at 50-keV compared to 70-keV VMI for all arteries: AA (36.54 and 48.28 vs. 25.70 and 28.46), CeA (22.39 and 48.38 vs. 19.09 and 29.15), SMA (23.34 and 49.34 vs. 19.67 and 29.71), RA (22.88 and 48.84 vs. 20.15 and 29.41), and RHA (14.38 and 44.41 vs. 13.45 and 27.18), all p < 0.05. Arterial lengths were also significantly longer at 50-keV: RHA (192.6 vs. 180.3 mm), SMA (230.9 vs. 216.5 mm), and RA (95.9 vs. 92.0 mm), all p < 0.001.

CONCLUSION

In abdominal CTA with PCD-CT, 50-keV VMI demonstrated superior quantitative image quality compared to 70-keV VMI. In addition, 50-keV VMI 3D CTA allowed better visualization of abdominal artery branches, highlighting its potential clinical advantage for improved imaging and detailed assessment of abdominal arteries.

Distance measurements and origin levels of the coeliac trunk, superior mesenteric artery, and inferior mesenteric artery by multiple-detector computed tomography angiography

The aim of this study is to determine vertebral levels of the coeliac trunk, the superior mesenteric artery, and the inferior mesenteric artery originated from the abdominal aorta and to calculate the distance measurements between these arteries and between these arteries and the aortic bifurcation by multidetector computed tomography angiography technique. It was determined that the nine different vertebral levels of the coeliac trunk, the nine different vertebral levels of the superior mesenteric artery, and the eleven different vertebral levels of the inferior mesenteric artery. The distance measurements between the coeliac trunk and the superior mesenteric artery, the inferior mesenteric artery, the aortic bifurcation were found significant between female and male. In this study, it was determined more different levels than the levels described in classical anatomy. The preoperative information of these morphological variations can contribute to the reduction of surgical time and perioperative vascular complications especially for anterior lumbar interbody fusion and defining the location of the primary lymphatic drainage site for gastrointestinal malignancies.

Computed Tomography Imaging Findings of Acute Aortic Pathologies

Acute aortic syndromes (AAS) encompass a spectrum of life-threatening conditions characterized by acute aortic pain. AAS include acute aortic dissection, intramural hematoma, penetrating atherosclerotic ulcer, and aneurysm rupture. The prognosis of AAS is clearly related to prompt diagnosis and appropriate management. The different types of AAS cannot be reliably differentiated solely based on clinical presentation since the clinical features are indistinguishable. Multidetector-row computed tomography (MDCT) with electrocardiographic gating (ECG-gated MDCT) has been used in the acute emergency setting as a powerful clinical tool, which enables rapid and specific diagnosis of aortic pathologies. ECG-gated MDCT significantly reduces motion artifact and avoids potential pitfalls in the diagnosis of AAS. The aim of this review is to evaluate the role of MDCT imaging in the assessment of AAS and to discuss the differentiation of this spectrum of aortic diseases with reference to the key imaging findings.

Multidetector-row Computed Tomographic Angiography in the Planning of the Local Perforator Flaps

Supplemental Digital Content is available in the text.

The perforator vessels are highly variable in number, localization types, hemodynamic specifications, and the anatomical interactions with other structures. For these reasons, the identification of the best perforator before the operation is very important for the choice of the main feed vessel and the design of the perforator flap.

Tumor feeding artery reconstruction with multislice spiral CT in the diagnosis of pelvic tumors of unknown origin

PURPOSE

We aimed to compare multislice spiral computed tomography (MSCT) angiography diagnosis with both surgical findings and postoperative pathological results in patients with pelvic tumors of unknown origin. In addition, the diagnostic accuracy of MSCT angiography was compared with that of routine computed tomography for tumor feeding artery volume reconstruction to determine the origin and nature of pelvic tumors.

MATERIALS AND METHODS

The records of 43 patients with pelvic tumors of unknown origin who underwent MSCT angiography were retrospectively reviewed. Volume reconstructions using add vessel and merge views methods were performed for abdominal and pelvic blood vessels. The tumor origin was identified based on observations of the origin, number, morphology, starting/ending locations, route, and distribution of the tumor feeding arteries.

RESULTS

Overall, the mean tumor diameter was 9.8±3.5 cm (range, 4.2-23.5 cm); 11 tumors (25.6%) were cystic in nature; and 32 tumors (74.4%) were either solid/cystic or solid in nature. When considering all MSCT angiography examinations used to predict the nature of the tumor (e.g., malignant or benign), the sensitivity and specificity were 77.3% and 95.2%, respectively. The positive and negative predictive values were 94.4% and 80%, respectively. The overall diagnostic accuracy was 86.05% with an area under the curve of 0.961 (95% confidence interval, 0.913-1.000).

CONCLUSIONS

MSCT angiography volume reconstruction for pelvic tumor feeding arteries of unknown origin is highly valuable for localization, qualitative diagnosis, and quantitative diagnosis of pelvic tumors.

The importance of multidetector computed tomography in the vascular imaging

A több detektorsoros spirál-CT-berendezések és a hozzájuk tartozó speciális rekonstrukciós szoftverek bevezetése lehetővé tette az erek jó minőségű CT-vizsgálatát. Cél és módszerek: A szerzők ismertetik a CT-angiográfiai vizsgálatok elvét, technikáját, amelyet az elmúlt három évben közel 700 saját betegükön végzett vizsgálataik eredményeivel, tapasztalataival egészítenek ki. Bemutatják a CT-angiográfia jelentőségét, valamint annak más vascularis képalkotó eljárások helyett vagy melletti alkalmazhatóságát. Következtetések: A CT-angiográfia gyors, noninvazív vizsgálati módszer, amellyel – önmagában vagy más vizsgálattal kiegészítve – pontos diagnózis állítható fel.

Assessment of aortic pathology and peripheral arterial disease using multidetector computed tomographic angiography

The development of multidetector computed tomography represents a remarkable diagnostic advancement because this imaging modality has been widely used in the evaluation of the cardiovascular system. With scanner-adjusted image acquisition and contrast medium administration, multidetector computed tomographic angiography provides a cost-effective and accurate imaging assessment in patients with aortic pathologies or peripheral arterial occlusive disease. Multidetector computed tomographic angiography is associated with several advantages, including high image spatial resolution and rapid imaging acquisition speed. This diagnostic methodology allows accurate detection of a variety of intravascular lesions in the carotid artery, thoracic and abdominal aorta, renal arteries, and peripheral arterial systems. This article provides an overview of multidetector computed tomographic angiography in the assessment of arterial disease and reviews current literature about this diagnostic technology in the evaluation of aortic and peripheral arterial pathologies.

Comparison of neutral oral contrast versus positive oral contrast medium in abdominal multidetector CT

To determine whether neutral contrast agents with water-equivalent intraluminal attenuation can improve delineation of the bowel wall and increase overall image quality for a non-selected patient population, a neutral oral contrast agent (3% mannitol) was administered to 100 patients referred for abdominal multidetector row computed tomography (MDCT). Their results were compared with those of 100 patients given a positive oral contrast agent. Qualitative and quantitative measurements were done on different levels of the gastrointestinal tract by three experienced readers. Patients given the neutral oral contrast agent showed significant better qualitative results for bowel distension (P < 0.001), homogeneity of the luminal content (P < 0.001), delineation of the bowel-wall to the lumen (P < 0.001) and to the mesentery (P < 0.001) and artifacts (P < 0.001), leading to a significant better overall image quality (P < 0.001) than patients receiving positive oral contrast medium. The quantitative measurements revealed significant better distension (P < 0.001) and wall to lumen delineation (P < 0.001) for the patients receiving neutral oral contrast medium. The present results show that the neutral oral contrast agent (mannitol) produced better distension, better homogeneity and better delineation of the bowel wall leading to a higher overall image quality than the positive oral contrast medium in a non-selected patient population.

Pancreatic cancer--low survival rates

INTRODUCTION

Cancers of the pancreas are identified in 11 800 to 13 500 patients each year in Germany. Epidemiological studies prove smoking and chronic alcohol consumption as causes of about 30% of pancreatic cancers.

METHODS

Selective literature review.

RESULTS

Only patients within TNM stage I and II have after oncologic tumor extirpation a chance for long term survival. Controlled prospective clinical trials demonstrated adjuvant chemotherapy yielding an additional significant survival benefit. The 3- and 5-year-survival after R0-resection and adjuvant chemotherapy are about 30% and below 15% respectively. Using the criteria of observed 5-year-survival less than 2% of all pancreatic cancer patients are alive. After R0-resection the median survival time is between 17 and 28 months, after R1/2-resection between 8 and 22 months.

DISCUSSION

Pancreatic cancer is even today for more than 95% of the patients incurable. Strategies to prevent pancreatic cancer are intended to stop smoking and chronic alcohol consumption and early surgical extirpation of cystic neoplastic lesions. For patients with established pancreatic cancer risk a follow-up protocol is discussed.

Multidetector computed tomography of the renal arteries in vascular emergencies

Multidetector computed tomography (MDCT) has drastically changed the diagnostic imaging protocol in both traumatic and non-traumatic vascular emergencies, replacing almost completely the traditional primary role of catheter angiography. MDCT is a well-established tool for the elective evaluation of stenoses, malformations, and dysplasias in the settings of renovascular hypertension, but probably less used in the settings of acute traumatic and non-traumatic clinical situations. The aim of this review is to define the role of MDCT in renal arteries emergencies.

Postpartum Hemoperitoneum Due to Avulsion of Pelvic Uterine Adhesion Band

A 31-year-old nulliparous woman presented in labor with preterm rupture of membranes at 35 weeks of gestation. The ensuing intrapartum course was uneventful, and she delivered a healthy infant (birth weight, 2,850 g) vaginally. Four hours after delivery, the patient had a syncopal episode due to hypovolemic shock. At laparotomy, a fibrous band between the right fallopian tube and uterus was found to be avulsed and actively bleeding, confirming preoperative findings obtained with multidetector row computed tomographic angiography.

Thoracoabdominal aorta coarctation with bilateral renal artery involvement: diagnosis with multidetector CT angiography (MDCTA)

Atypical coarctation of the descending thoracic and abdominal aorta is a very uncommon vascular disease. Congenital, acquired, inflammatory, and infectious etiologies have been proposed. Patients typically presents with uncontrolled secondary hypertension in the upper half of the body or hypotension in the lower extremities in the first three decades of their lives. We report the case of a 20-year-old man with severe hypertension. Diffuse coarctation of thoracoabdominal aorta associated with bilateral renal artery stenosis was demonstrated clearly by multidetector CT angiography. This is the first case of atypical aortic coarctation diagnosed by MDCTA.

Low-attenuation oral GI contrast agents in abdominal-pelvic computed tomography

BACKGROUND

We designed and evaluated a low-attenuation oral contrast agent for abdominal-pelvic computed tomography (CT).

METHODS

In vitro studies, were performed initially to evaluate the imaging characteristics of multiple solutions. These studies resulted in two solutions being compared with the presently accepted oral CT agents of dilute iodinated contrast and water. Ninety-eight consecutive subjects already scheduled for routine outpatient abdominal-pelvic CT were enrolled. Subjects were randomized to water (n = 30), fiber solution (n = 32), polyethylene glycol (PEG; n = 11), or dilute iodinated solution (DI; n = 25). Examinations were then evaluated for gastric distention, small bowel distention, small bowel wall visualization, and colonic transit. A questionnaire was given to the study subjects for feedback concerning taste and potential side effects from these agents.

RESULTS

PEG tended to provide better bowel distention, wall visualization, and colonic transit compared with water, fiber solution, and DI. Areas of statistical significance included: (1) average bowel diameter in the left upper quadrant for water was 17.50 mm, whereas that for PEG was 21.88 mm (p < 0.05); (2) average bowel diameter in the pelvis for water was 14.79 mm, that for fiber was 15.67 mm, and that for PEG was 18.48 mm (p < 0.05); (3) wall visualization was better with PEG than with fiber (p < 0.05); (4) successful transit of contrast to the colon occurred in every subject who received PEG compared with only 20% of those received water and 39% of those who received fiber (p < 0.05). Similar trends for the superiority of PEG over DI were noted, although many of these did not reach statistical significance.

CONCLUSION

PEG solution has imaging characteristics related to bowel wall visualization, luminal distention, and colonic transit that make it an effective oral agent for abdominal pelvic CT examination.

Renal Multidector Row CT

Multidetector row CT is the most recent advance in CT technology. An increased number of detector rows and more powerful x-ray tubes result in faster scanning time, increased volume coverage, and improved spatial and temporal resolution. MDCT technology allows superior image quality, decreased examination time, and the ability to perform complex multiphase vascular and three-dimensional examinations.

Multidetector CT Angiography of the Abdomen

Multidetector CT angiography (MDCTA) is redefining traditional imaging strategies of the vascular structures of the abdomen. Angiographic depiction of normal and variant anatomy is becoming the standard for evaluation and has a significant impact in transplant and oncologic surgery. MDCTA is increasingly being used for assessing diseases affecting the vasculature of the abdominal organs, including the abdominal aorta for treatment planning and post therapy follow-up.

Acute aortic syndromes: aortic dissections, penetrating aortic ulcers and intramural aortic hematomas

Acute aortic syndromes, including dissections, intramural hematomas and penetrating aortic ulcers, are a catastrophic clinical entity that are relatively uncommon. A high index of clinical suspicion along with proper imaging modalities are critical in making a prompt and accurate diagnosis for immediate management and to improve survival of the patient.

[Cardiovascular whole-body MRI: possibilities and limitations in prevention]

Cardiovascular disease is a major challenge to the healthcare with increasing prevalence in western societies. Hence, early detection of cardiovascular pathologies and preventative strategies will experience growing relevance in the future. Magnetic resonance imaging (MRI) nowadays allows a comprehensive analysis of the cardiovascular system. By combining separate examinations of brain, arterial vasculature, and heart the technique permits early detection of pathological changes with high diagnostic accuracy void of adverse events. Such a protocol has been proven feasible and technically robust and can be performed within 45 min. Inherent limitations are low spatial resolution of whole-body MR angiography and lack of functional stress testing of the heart. However, while being suitable as a fast and comprehensive imaging technique for cardiovascular screening purposes, medical consequences and socioeconomic relevance must further be elucidated.