Hatem Alkadhi, M.D.

The HPS mode of 128-slice dual-source CT yields fewer artefacts inside the stent lumen compared with SPIR and SEQ, but image noise is higher. Read more

Our results indicate that DSCT provides reliable measurements of LV dimensions, volumes, and myocardial mass with similar values as compared with echocardiography. Read more

Detailed knowledge of aortic root geometry is a prerequisite to anticipate complications of transcatheter aortic valve (TAV) implantation. We determined coronary ostial locations and aortic root dimensions in patients with aortic stenosis (AS) and compared these values with normal subjects using computed tomography (CT). Read more

pECG(dual-step)128-slice DSCT is feasible for the evaluation of coronary arteries and cardiac function without heart rate control in patients in stable sinus rhythm at a low radiation dose. Read more

Case history: 51-year-old male patient who had suffered from single episode of rypical chest oain afrw days before wa referres ro cadiac CT to rule out significant stenoses of the coronary arteries. History of high cholesterol and a positive family history of cardiovascular disease. Since the patient showed a stable … Read more

We describe the case of a 59-year-old man who had aortic regurgitation and a hypoplastic aortic valve and for whom an echocardiography evaluation revealed a vascular tumor in the roof of the left atrium, which was suspected to be a hemangioma. Read more

Cardiac computed tomography (CT) represents a reliable and accurate modality for the diagnosis and exclusion of coronary artery disease. A huge number of studies have investigated the diagnostic performance of CT coronary angiography among different generations of CT scanners. Nevertheless, radiation doses still remain a matter of concern. Read more

To prospectively investigate computed tomographic (CT) image quality parameters by using different protocols and to calculate radiation dose estimates for noninvasive coronary angiography performed with dual-source CT in the step-and-shoot (SAS) mode. Read more

Editorial Journal of Cardiovascular Computed Tomography (2008) 2 The number of diagnostic cardiac imaging tests involving x-rays has increased in the past decades. For example, the volume of diagnostic catheter angiography procedures performed in the United States increased from 2.45 million in 1993 to 3.85 million in 2002. (1) Similarly, the … Read more

Abstract Objectives The aim of this study was to assess the value of multislice computed tomography (CT) for the assessment of valvular abnormalities in patients with infective endocarditis (IE) in comparison with transesophageal echocardiography (TEE) and intraoperative findings. Background Multislice CT has recently shown promising data regarding valvular imaging in a 4-dimensional … Read more

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Abstract Current evidence and most pertinent literature on the radiation dose of cardiac computed tomography (CT) for the noninvasive assessment of coronary artery disease are reviewed. The various means for adjusting CT protocols to lower the radiation to a level that is as low as reasonably achievable are discussed. It … Read more

Purpose: To assess the diagnostic performance of dual-energy dual-source computed tomography (CT) in the detection of endoleaks after endovascular abdominal aortic aneurysm (AAA) repair. Materials and Methods: This study was local ethics board approved, and written informed consent was obtained from all patients. One hundred eighteen patients (21 women, 97 men; mean age, … Read more

To overcome the limitations of the classical volume scoring method for quantifying coronary calcifications, including accuracy, variability between examinations, and dependency on plaque density and acquisition parameters, a mesh-based volume measurement method has been developed. It was evaluated and compared with the classical volume scoring method for accuracy, i.e., the normalized … Read more

Purpose The purpose of this study was to assess the radiation dose and associated image noise of previously suggested calcium scoring protocols using dual-source CT. Methods One hundred consecutive patients underwent coronary calcium scoring using dual-source CT. Patients were randomly assigned to five different protocols: retrospective ECG-gating and tube current reduction to … Read more

Bun Yok O. Dy, M.D., China, has sent the following question: Somatom vs Lightspeed CT750HD: We are considering acquisition of a high speed CT with coronary and peripheral capabilities, which would be a better choice, the Siemen’s Somatom DSCT or GE Lightspeed CT 750HD? Hatem Alkadhi, Institute of Diagnostic Radiology, University Hospital Zurich: Dear … Read more

We assessed the potential of dual-energy computed tomography (CT) for the differentiation between uric acid (UA)-containing and non-UA-containing urinary stones. Forty urinary stones of 16 different compositions in two sizes (< and >/= 5 mm) were examined in an ex vivo model. Thirty stones consisted of pure calcium oxalate (whewellite or … Read more

To assess reference values for left ventricular (LV) and left atrial (LA) dimensions, global LV function, and LV-myocardial mass for cardiac CT. We examined 120 subjects undergoing a coronary angiography using 64-slice and dual-source CT. All individuals had a low cardiovascular risk, normal ECG, negative biomarkers, and a normal cardiac CT … Read more

The following question has been sent by Bellalize Steenkamp, radiographer, Unitas Hospital, South Africa: 1) Would you say that the DSCT is better equipped to do Paediatrics than the normal multi-slice CT? 2) In certain cases, due to the less invasive procedure, would you say it is more appropriate than doing an … Read more

The following question has been sent by Bellalize Steenkamp, radiographer, Unitas Hospital, South Africa: Is there a place for DSCT in paediatric diagnoses? Hatem Alkadhi, M.D., University Hopsital Zurich, Switzerland: Dear Ms Steenkamp Thank you for your question regarding the use of DSCT in pediatric patients. The answer is: Yes. First, you may perform any DSCT … Read more

Abstract Objective We investigated the performance of low-dose dual-source computed tomography (DSCT) coronary angiography in the step-and-shoot (SAS) mode for the diagnosis of significant coronary artery stenoses in comparison with conventional coronary angiography (CCA). Design, Setting and Patients Prospective, single-center study conducted in a referral center enrolling 120 patients (71 males, age 68 +/-9 … Read more

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HISTORY A 71-year-old male patient presented with painful swelling of the first metatarsophalangeal joint of the left foot. The routine clinical-chemical work-up showed a slight hyperuricaemia and mild renal insufficiency. In order to conclusively assess the cause of arthritis the patient underwent puncture … Read more

The following question has been sent by Sofiane Hadjadj, MD, clinical research, Canada: For the diagnosis and follow-up of aortic aneurysms the aortic ECG guating ct scan have shown it accuracy beside echo, we still no have concensus about which phase we should measure the aortic diameters, some surgeons here prefere … Read more

Subvalvular aortic stenosis (SAS) represents a fixed obstruction of the left ventricular outflow tract (LVOT) by an endocardial fold, fibrous tissue, or fibromuscular ridge. Echocardiography including color Doppler is the modality of choice to establish the diagnosis and to assess the extent and hemodynamic severity of SAS. We present imaging … Read more

A 75-year-old woman was admitted to our emergency department with severe chest pain and mild dyspnea that started soon after a marital quarrel with her husband. Her 12-lead electrocardiogaphy (ECG) demonstrated an ST elevation in the precordial leads, and the plasma troponin T level was elevated to 0.29 ng/mL. An … Read more

Jul 11, 2008 to Jul 12, 2008. Institute for Diagnostic Radiology, University Hospitals Zurich, Switzerland Due to the positive resonance to our recent hands-on workshops, we have retained the workshop content essentially unchanged. We will offer another theoretical basic course that deals with the basics of anatomy and CT physics and goes on to explain the major indications … Read more

The advent of multidetector row spiral computed tomography (CT) is one of the most groundbreaking innovations in the field of diagnostic imaging over the past decade. Because of the high temporal and spatial resolution of recent single-source and dual-source CT scanner types, robust CT imaging of the coronary arteries has … Read more

Aims: To prospectively investigate the diagnostic accuracy of dual-source computed tomography coronary angiography (CTCA) to diagnose coronary stenoses in relation to body mass index (BMI), Agatston score (AS), and heart rate (HR) as compared with catheter coronary angiography (CCA). Methods and results: Hundred and fifty consecutive patients (47 female, mean age … Read more

The following question has been sent by Luke Riverstone, Radiographer, Qscan Radiology Clinics, Australia: We have recently obtained a Siemens DSCT.  We performed our first DE KUB the other day and the Dual Energy Software indicated that there was 1 Kidney stone that was of a Uric Acid composition and 1 was … Read more

Abstract Objectives: To assess the value of dual-energy contrast-enhanced computed tomography (CT) imaging for the detection of urinary stone disease using dual-source CT. Materials and Methods: Forty consecutive patients (mean age 46.6 ± 16.2 years, range 27–85 years) suspected of having urinary stone disease underwent dual-source CT of the urinary tract. A … Read more

Please click on the title to see the protocol. Read more

Case history A 51-year-old male patient, who had suffered a single episode of atypical chest pain a few days prior, was referred to cardiac CT to rule out severe calcification and significant stenoses of the coronary arteries. The patient had a history of high cholesterol as well as a positive family … Read more

The following question has been asked by Y.S.Lee, Singapore: Objective methods to determine minimal required Kv and mAs for DSCT cardiac: For DS cardiac CT, the optimal Kv and mAs used by radiographers at time can be suboptimum depending on their experiences. Using BMI method, can at … Read more

Abstract Objective: To prospectively investigate the diagnostic accuracy of dual-source 64-slice computed tomography coronary angiography (CTCA), calcium scoring (CS), and both methods combined for assessing significant coronary artery stenoses relative to conventional coronary angiography (CCA). Design, Setting and Patients: Prospective, single-center study conducted in a referral center enrolling 74 consecutive patients … Read more

SOMATOM Definition vascular CTA History A 71-year-old man arrives in the University Hospital Zurich with a long history of diabetes. After short walks of 100 meter the patient complains of severe pain in the lower extremities, forcing him to pause. In the initial ultrasound diagnosis a severe occlusion of the left arteria … Read more

Abstract The aim of this study was to determine the feasibility and image quality of dual-source computed tomography angiography (DSCTA) in patients with acute chest pain for the assessment of the lung, thoracic aorta, and for pulmonary and coronary arteries. Sixty consecutive patients (32 female, 28 male, mean age 58.1± 16.3 … Read more

Abstract The purpose of this study was to quantify radiation dose parameters of dual-source CT coronary angiography. Eighty patients underwent contrast-enhanced, retrospectively ECG-gated dual-source CT coronary angiography with heart rate-adapted ECG pulsing using two algorithms: In 40 patients, the tube current was reduced to 20% (Amin1) of the normal tube current … Read more

Recommendations for ECG-Pulsing Windowing Abstract Purpose: To evaluate reconstruction intervals and image quality in dual-source computed tomography (DSCT) coronary angiography for optimal placement of the ECG-pulsing window. Materials and Methods: DSCT coronary angiography was performed in 60 patients. Thirteen datasets were reconstructed in 5% increments from 20–80%. Two readers independently assessed image quality … Read more

Abstract The aim of this study was to assess the diagnostic accuracy of dual source computed tomography (DSCT) for evaluation of coronary artery disease (CAD) in a population with extensive coronary calcifications without heart rate control. Thirty patients (24 male, 6 female, mean age 63.1±11.3 years) with a high pre-test probability … Read more

Abstract Objective. The purpose of this study was to evaluate the effect of mean heart rate and heart rate variability on the image quality of dual-source CT coronary angiography. Subjects and methods. Eighty patients underwent dual-source CT coronary angiography. Thirteen data sets were reconstructed in 5% steps from 20–80% of the R-R … Read more