Virtual non-contrast images in photon-counting computed tomography: impact of different contrast phases.

Background: Photon-counting computed tomography (PCCT) enables new ways of image reconstruction, e.g. material decomposition and creation of virtual non-contrast (VNC) series with higher resolution and lower radiation dose than standard computed tomography (CT).

Change in tissue resistance after irreversible electroporation in liver tumors as an indicator of treatment success - A multi-center analysis with long term follow-up.

Introduction: A nationwide multicenter study was performed to examine whether there is a correlation between decrease in tissue resistance and time to local tumor recurrence after irreversible electroporation (IRE) in patients with hepatocellular carcinoma (HCC) and colorectal cancer liver metastases (CRCLM).

Methods: All patients treated with IRE for liver tumors in Sweden from 2011 until 2018 were included. Patient characteristics and recurrence patterns were obtained from medical records and radiological imaging.

No gadolinium K-edge detected on the first clinical photon-counting computed tomography scanner.

Purpose: This study aimed to elucidate whether gadolinium contrast in clinically relevant doses can be used with photon-counting computed tomography (PCCT) as an alternative contrast agent in clinical applications.

Material/methods: A CTDI phantom with 3D printed rods filled with different concentrations of gadolinium and iodine contrast was scanned in a PCCT and an energy-integrated computed tomography (EICT). Attenuation values at different monoenergetic steps were extracted for each contrast concentration.

Portal vein embolization with N-butyl-cyanoacrylate improves liver hypertrophy compared to microparticles - A Swedish multicenter cohort study.

Background: An adequate future liver remnant (FLR) is fundamental for major liver resections. To achieve sufficient FLR, portal vein embolization (PVE) may be used. The most effective material for PVE has yet to be determined.

Irreversible electroporation of hepatocellular carcinoma and colorectal cancer liver metastases: A nationwide multicenter study with short- and long-term follow-up.

Introduction: A nationwide multicenter study was performed to examine short- and long-term effects of irreversible electroporation (IRE) for hepatocellular carcinoma (HCC) and colorectal cancer liver metastases (CRCLM). IRE is an alternative method when thermal ablation is contraindicated because of risk for serious thermal complications.

Methods: All consecutive patients in Sweden treated with IRE because of HCC or CRCLM, were included between 2011 and 2018.

EVALUATION OF MODEL-BASED ITERATIVE RECONSTRUCTION IN ABDOMINAL COMPUTED TOMOGRAPHY IMAGING AT TWO DIFFERENT DOSE LEVELS.

The purpose of this study was to qualitatively evaluate recently introduced Model-based iterative reconstruction method (IMR) and routinely used iterative reconstruction algorithm iDose4 to investigate future dose reduction possibilities for abdominal CT exams. The study contained data from 34 patients who underwent abdominal CT in SkåneUniversityHospital Lund, Sweden. A low-dose scan (CTDIvol3.

Can iterative reconstruction algorithms replace tube loading compensation in low kVp hepatic CT? Subjective versus objective image quality.

Background: Hepatic computed tomography (CT) with decreased peak kilovoltage (kVp) may be used to reduce contrast medium doses in patients at risk of contrast-induced acute kidney injury (CI-AKI); however, it increases image noise. To preserve image quality, noise has been controlled by X-ray tube loading (mAs) compensation (TLC), i.e.

Pancreatic cancer: yesterday, today and tomorrow.

Pancreatic cancer is one of our most lethal malignancies. Despite substantial improvements in the survival rates for other major cancer forms, pancreatic cancer survival rates have remained relatively unchanged since the 1960s. Pancreatic cancer is usually detected at an advanced stage and most treatment regimens are ineffective, contributing to the poor overall prognosis.

Impact of iterative reconstructions on image noise and low-contrast object detection in low kVp simulated abdominal CT: a phantom study.

Background: Low kilovoltage (kVp) computed tomography (CT) may be used to reduce contrast medium dose in patients at risk of contrast nephropathy, at the cost of increased image noise.

Purpose: To evaluate: (i) the impact of iterative reconstructions (Siemens SAFIRE) on low-contrast object detection to compensate for increased noise instead of increased tube loading when decreasing tube potential; and (ii) the change in iodine attenuation in simulated abdominal CT.

Material And Methods: A phantom was scanned at 70, 80, 100, and 120 kVp at fixed effective tube loading (170 mAsEFF) and fixed radiation dose (CTDIVOL 10 mGy).

Anesthesia for catheter ablation procedures.

Over the past decade, the role of the anesthesiologist has evolved continuously into a sine qua non component of the EP team, having intimate knowledge of the complex interventional procedures and the specific demands of the EP environment. With emphasis on coordination of care, resource optimization, and implementation of a climate of teamwork and collaboration, the anesthesiologist very likely will assume an even more enhanced role in the future. Future design of the EP suite ergonomics must take into account the needs of the anesthesia team to improve procedural workflow and maintain the focus on the patient.

Ultralow contrast medium doses at CT to diagnose pulmonary embolism in patients with moderate to severe renal impairment: a feasibility study.

Objectives: To analyse 80-kVp 16-MDCT in patients with clinically suspected pulmonary embolism (PE) and diminished renal function after a reduction in dose of contrast medium (CM) from 200 to 150 mg I/kg.

Methods: Fifty patients with suspected PE and glomerular filtration rate (GFR) less than 50 mL/min underwent 80-kVp 16-MDCT with 150 mg I/kg. Mean density/image noise (1 standard deviation) was measured in a region of interest in the left pulmonary artery (LPA) and a lower lobe segmental artery (LLSA), and the contrast-to-noise ratio (CNR) was calculated.

Minimizing contrast medium doses to diagnose pulmonary embolism with 80-kVp multidetector computed tomography in azotemic patients.

Background: In diagnosing acute pulmonary embolism (PE) in azotemic patients, scintigraphy and magnetic resonance imaging are frequently inconclusive or not available in many hospitals. Computed tomography is readily available, but relatively high doses (30-50 g I) of potentially nephrotoxic iodine contrast media (CM) are used.

Purpose: To report on the diagnostic quality and possible contrast-induced nephropathy (CIN) after substantially reduced CM doses to diagnose PE in azotemic patients using 80-peak kilovoltage (kVp) 16-row multidetector computed tomography (MDCT) combined with CM doses tailored to body weight, fixed injection duration adapted to scan time, automatic bolus tracking, and saline chaser.

Eighty-peak kilovoltage 16-channel multidetector computed tomography and reduced contrast-medium doses tailored to body weight to diagnose pulmonary embolism in azotaemic patients.

The aim of this study was to assess the feasibility of minimising contrast-medium (CM) doses using 80-peak kilovoltage (kVp) 16-channel multidetector computed tomography (MDCT) with CM dose tailored to body weight, when diagnosing pulmonary embolism (PE) in azotaemic patients. Twenty-nine patients (68-93 years; 38-79 kg) with an estimated glomerular filtration rate of 12-49 ml/min underwent 80 kVp MDCT at a median dose of 200 mg iodine (I)/kg and 15 s injection time. Pulmonary artery (PA) enhancement where compared with our own reference material using 320 mg I/kg at 120 kVp and with reported figures in the literature at 120-140 kVp and a 42 g iodine CM dose.

Some pre- and postjunctional effects of castration in rabbit isolated corpus cavernosum and urethra.

Pre- and postjunctional effects of castration were investigated in isolated corpus cavernosum (CC) and prostatic and preprostatic urethral preparations obtained from rabbits that had been castrated surgically 14 days before investigation. Preparations obtained from untreated animals were used as controls. Castration did not change the relaxing effects of SIN-1 (NO donor) or papaverine in CC preparations contracted by noradrenaline (NA).

Effects of nicorandil on human isolated corpus cavernosum and cavernous artery.

Nitric oxide (NO) released from nonadrenergic-noncholinergic (NANC) nerves seems to be a principal mediator of the relaxation of penile erectile tissue necessary for erection, and drugs acting by release of NO have been shown to produce erection when injected intracorporeally into impotent patients. By producing hyperpolarization, K+ channel openers are effective in relaxing isolated penile erectile tissue from rabbit and man, and can produce tumescence and erection when injected intracorporeally into animals. Nicorandil is classified as a K+ channel opener, but it also acts as a donor of NO.

Regulation of tone in penile cavernous smooth muscle. Established concepts and new findings.

Since Benson, in 1983, reported on a potent nonadrenergic, noncholinergic (NANC) transmitter postulated to relax penile vessels and the corpus cavernosum, much new information on the mechanisms of contraction and relaxation of corporeal smooth muscle and penile vasculature has been obtained. The information currently available suggests that NANC transmitters may be involved in both contractile and relaxant responses of penile erectile tissues. There is good experimental evidence to allow the assumption that neurogenic nitric oxide (NO) is a mediator of penile erection, but even if NO probably is the most important factor for relaxation of penile vessels and the corpus cavernosum, this does not exclude the possibility that other agents released from nerves may have a modulatory function in this process.

Actions of 3-morpholinosydnonimin (SIN-1) on rabbit isolated penile erectile tissue.

The effects of the NO-donor 3-morpholinosydnonimin (SIN-1) on isometric tension, cyclic guanosine 3',5'-monophosphate (cyclic GMP) accumulation and neuronal release of 3H-noradrenaline were investigated in rabbit isolated corpus cavernosum (CC), and compared to the actions of sodium nitroprusside (SNP) and the cyclic GMP-specific phosphodiesterase inhibitor zaprinast. SIN-1, zaprinast and SNP concentration dependently relaxed rabbit CC preparations contracted by 1 microM. phenylephrine.

Endothelin-1-induced phosphoinositide hydrolysis and contraction in isolated rabbit detrusor and urethral smooth muscle.

1. Endothelin-1 (ET-1) caused a concentration-dependent increase in the formation of inositol phosphates (IPs) in isolated rabbit detrusor and urethral smooth muscle preparations prelabelled with myo-[3H]inositol. 2.

Preliminary results with the nitric oxide donor linsidomine chlorhydrate in the treatment of human erectile dysfunction.

Recent experimental studies showed an important role of endothelium derived relaxing factor for cavernous smooth muscle relaxation. Since nitric oxide seems to account for the biological actions of endothelium derived relaxing factor, a study was done to examine a possible role of the nitric oxide donor linsidomine chlorhydrate (SIN-1) in the treatment of erectile dysfunction. To determine a therapeutically useful dose 0.

Phospholipase C activation by endothelin-1 and noradrenaline in isolated penile erectile tissue from rabbit.

The effects of endothelin-1 and noradrenaline on phospholipase C activity in the rabbit isolated corpus cavernosum were investigated by measuring the accumulation of inositol phosphates. Both endothelin-1 and noradrenaline caused a time- and concentration-dependent increase in the accumulation of 3H-inositol phosphates in preparations prelabelled with 3H-myo-inositol. The reaction was slow in onset with no significant accumulation of 3H-inositol phosphates, including inositol trisphosphate, demonstrable during the first 15 minutes.

Functional effects, binding sites and immunolocalization of endothelin-1 in isolated penile tissues from man and rabbit.

Functional effects of endothelin-1 (ET-1) were investigated in isolated preparations of human and rabbit corpus cavernosum (CC) and human penile circumflex veins (CV). In all preparations, ET-1 induced slowly developing, concentration-dependent contractions. The threshold concentration of ET-1 in CV was approximately 10 and 112 times lower than the threshold concentrations in human and rabbit CC, respectively.