Spiral 2D T2-Weighted TSE Brain MR Imaging: Initial Clinical Experience.

BACKGROUND AND PURPOSE: Spiral MR imaging may enable improved image quality and higher scan speeds than Cartesian trajectories. We sought to compare a novel spiral 2D T2-weighted TSE sequence with a conventional Cartesian and an artifact-robust, non-Cartesian sequence named MultiVane for routine clinical brain MR imaging. MATERIALS AND METHODS: Thirty-one patients were scanned with all 3 sequences (Cartesian, 4 minutes 14 seconds; MultiVane, 2 minutes 49 seconds; spiral, 2 minutes 12 seconds) on a standard clinical 1.5T MR scanner. Three readers described the presence and location of abnormalities and lesions and graded images qualitatively in terms of overall image quality, the presence of motion and pulsation artifacts, gray-white matter differentiation, lesion conspicuity, and subjective preference. Image quality was objectivized by measuring the SNR and the coefficients of variation for CSF, GM, and WM. RESULTS: Spiral achieved a scan time reduction of 51.9% and 21.9% compared with Cartesian and MultiVane, respectively. The number and location of lesions were identical among all sequences. As for the qualitative analysis, interreader agreement was high (Krippendorff α > .75). Spiral and MultiVane both outperformed the Cartesian sequence in terms of overall image quality, the presence of motion artifacts, and subjective preference (P < .001). In terms of the presence of pulsation artifacts, gray-white matter differentiation, and lesion conspicuity, all 3 sequences performed similarly well (P > .15). Spiral and MultiVane outperformed the Cartesian sequence in coefficient of variation WM and SNR (P < .01). CONCLUSIONS: Spiral 2D T2WI TSE is feasible for routine structural brain MR imaging and offers high-quality, artifact-robust brain imaging in short scan times.

Preoperative portal vein or portal and hepatic vein embolization: DRAGON collaborative group analysis.

BACKGROUND: The extent of liver resection for tumours is limited by the expected functional reserve of the future liver remnant (FRL), so hypertrophy may be induced by portal vein embolization (PVE), taking 6 weeks or longer for growth. This study assessed the hypothesis that simultaneous embolization of portal and hepatic veins (PVE/HVE) accelerates hypertrophy and improves resectability. METHODS: All centres of the international DRAGON trials study collaborative were asked to provide data on patients who had PVE/HVE or PVE on 2016-2019 (more than 5 PVE/HVE procedures was a requirement). Liver volumetry was performed using OsiriX MD software. Multivariable analysis was performed for the endpoints of resectability rate, FLR hypertrophy and major complications using receiver operating characteristic (ROC) statistics, regression, and Kaplan-Meier analysis. RESULTS: In total, 39 patients had undergone PVE/HVE and 160 had PVE alone. The PVE/HVE group had better hypertrophy than the PVE group (59 versus 48 per cent respectively; P = 0.020) and resectability (90 versus 68 per cent; P = 0.007). Major complications (26 versus 34 per cent; P = 0.550) and 90-day mortality (3 versus 16 per cent respectively, P = 0.065) were comparable. Multivariable analysis confirmed that these effects were independent of confounders. CONCLUSION: PVE/HVE achieved better FLR hypertrophy and resectability than PVE in this collaborative experience.

Diffusion-Weighted Zonal Oblique Multislice-EPI Enhances the Detection of Small Lesions with Diffusion Restriction in the Brain Stem and Hippocampus: A Clinical Report of Selected Cases.

Diffusion restriction is the morphologic hallmark of acute ischemic infarcts and excitotoxic brain injury in various cerebral pathologies. Diffusion restriction is visible as hyperintensity on DWI and as hypointensity on ADC maps. Due to the vicinity of multiple anatomic structures in the brain stem and hippocampus, very small lesions with diffusion restriction may result in severe clinical symptomatology, but these small lesions easily go undetected on standard cerebral DWI due to insufficient spatial resolution, T2* blurring, and image artifacts caused by susceptibility-related image distortions. Diffusion-weighted zonal oblique multislice-EPI with reduced FOV acquisition permits a considerable increase in spatial resolution and enhances the visualization of very small pathologic lesions in the brain stem and hippocampus. Improved performance in the depiction of different pathologic lesions with diffusion restriction in the brain stem and hippocampus using this sequence compared with standard DWI in selected cases is presented.

How Common Is Signal-Intensity Increase in Optic Nerve Segments on 3D Double Inversion Recovery Sequences in Visually Asymptomatic Patients with Multiple Sclerosis?

BACKGROUND AND PURPOSE: In postmortem studies, subclinical optic nerve demyelination is very common in patients with MS but radiologic demonstration is difficult and mainly based on STIR T2WI. Our aim was to evaluate 3D double inversion recovery MR imaging for the detection of subclinical demyelinating lesions within optic nerve segments. MATERIALS AND METHODS: The signal intensities in 4 different optic nerve segments (ie, retrobulbar, canalicular, prechiasmatic, and chiasm) were evaluated on 3D double inversion recovery MR imaging in 95 patients with MS without visual symptoms within the past 3 years and in 50 patients without optic nerve pathology. We compared the signal intensities with those of the adjacent lateral rectus muscle. The evaluation was performed by a student group and an expert neuroradiologist. Statistical evaluation (the Cohen κ test) was performed. RESULTS: On the 3D double inversion recovery sequence, optic nerve segments in the comparison group were all hypointense, and an isointense nerve sheath surrounded the retrobulbar nerve segment. At least 1 optic nerve segment was isointense or hyperintense in 68 patients (72%) in the group with MS on the basis of the results of the expert neuroradiologist. Student raters were able to correctly identify optic nerve hypersignal in 97%. CONCLUSIONS: A hypersignal in at least 1 optic nerve segment on the 3D double inversion recovery sequence compared with hyposignal in optic nerve segments in the comparison group was very common in visually asymptomatic patients with MS. The signal-intensity rating of optic nerve segments could also be performed by inexperienced student readers.

Cirse Quality Assurance Document and Standards for Classification of Complications: The Cirse Classification System.

Interventional radiology provides a wide variety of vascular, nonvascular, musculoskeletal, and oncologic minimally invasive techniques aimed at therapy or palliation of a broad spectrum of pathologic conditions. Outcome data for these techniques are globally evaluated by hospitals, insurance companies, and government agencies targeting in a high-quality health care policy, including reimbursement strategies. To analyze effectively the outcome of a technique, accurate reporting of complications is necessary. Throughout the literature, numerous classification systems for complications grading and classification have been reported. Until now, there has been no method for uniform reporting of complications both in terms of definition and grading. The purpose of this CIRSE guideline is to provide a classification system of complications based on combining outcome and severity of sequelae. The ultimate challenge will be the adoption of this system by practitioners in different countries and health economies within the European Union and beyond.

[Evaluation in medical residency training programs]. / Evaluation in der Assistenzarztausbildung.

BACKGROUND: For resident doctors the acquisition of technical and professional competence is decisive for the successful practice of their activities. Competency and professional development of resident doctors benefit from regular self-reflection and assessment by peers. While often promoted and recommended by national educational authorities, the implementation of a robust evaluation process in the clinical routine is often counteracted by several factors. OBJECTIVE: The aim of the study was to test a self-developed digital evaluation system for the assessment of radiology residents at our institute for practicality and impact with regard to the radiological training. MATERIAL AND METHODS: The intranet-based evaluation system was implemented in January 2014, which allowed all Radiology consultants to submit a structured assessment of the Radiology residents according to standardized criteria. It included 7 areas of competency and 31 questions, as well as a self-assessment module, both of which were filled out electronically on a 3-month basis using a 10-point scale and the opportunity to make free text comments. The results of the mandatory self-evaluation by the residents were displayed beside the evaluation by the supervisor. Access to results was restricted and quarterly discussions with the residents were conducted confidentially and individually. RESULTS AND DISCUSSION: The system was considered to be practical to use and stable in its functionality. The centrally conducted anonymous national survey of residents revealed a noticeable improvement of satisfaction with the institute assessment for the criterion "regular feedback"compared to the national average. Since its implementation the system has been further developed and extended and is now available for other institutions.

[Unusual course of a planned lumbar microdiscectomy]. / Ungewöhnlicher Verlauf einer elektiv geplanten lumbalen Bandscheibenoperation.

We report the case of a 30-year-old female patient who underwent unilateral transverse sinus stenosis stenting due to a newly diagnosed idiopathic intracranial hypertension (Pseudotumor cerebri) with symptoms of papilledema, decreased visual acuity and headache. Resolution of the symptoms and improvement of magnetic resonance and ophthalmiologic findings could be documented.

[Inferior vena cava thrombosis after laparoscopy]. / Thrombose der Vena cava Inferior nach Diagnostischer Laparoskopie.

HISTORY AND FINDINGS: A previously healthy 43-year-old woman was admitted because of pain in the lower abdomen. Abdominal and transvaginal ultrasound revealed a cystic structure in the right ovary, providing the indication for an exploratory laparoscopy. A hemorrhagic corpus luteum was enucleated. Laboratory tests had merely shown a raised C-reactive protein level and marginally elevated leukocytes. A family history of thrombotic episodes had been elicited. FURTHER COURSE, DIAGNOSIS AND TREATMENT: Although heparin had been applied increasing swelling developed in both thighs and lower legs at day six, indicating thrombosis of the inferior vena cava. Laboratory tests revealed a mutation in factor V (Leiden). Computed tomography showed complete thrombotic IVC occlusion. Thrombolytic treatment with recombinant tissue plasminogen was initiated, direct thrombus aspiration attempted and a filter inserted in the IVC. Low molecular heparin was infused, replaced by oral anticoagulation with phenprocoumon. Subsequent Doppler ultrasound examination demonstrated almost complete resolution of the thrombus, except for a few small residual thrombi. CONCLUSION: This case demonstrates that even minor laparoscopic interventions carry the risk of an IVC thrombosis as a late complication, indicating appropriate measures to prevent thrombosis.

Insula-specific responses induced by dental pain. A proton magnetic resonance spectroscopy study.

OBJECTIVES: To evaluate whether induced dental pain leads to quantitative changes in brain metabolites within the left insular cortex after stimulation of the right maxillary canine and to examine whether these metabolic changes and the subjective pain intensity perception correlate. METHODS: Ten male volunteers were included in the pain group and compared with a control group of 10 other healthy volunteers. The pain group received a total of 87-92 electrically induced pain stimuli over 15 min to the right maxillary canine tooth. Contemporaneously, they evaluated the subjective pain intensity of every stimulus using an analogue scale. Neurotransmitter changes within the left insular cortex were evaluated by MR spectroscopy. RESULTS: Significant metabolic changes in glutamine (+55.1%), glutamine/glutamate (+16.4%) and myo-inositol (-9.7%) were documented during pain stimulation. Furthermore, there was a significant negative correlation between the subjective pain intensity perception and the metabolic levels of Glx, Gln, glutamate and N-acetyl aspartate. CONCLUSION: The insular cortex is a metabolically active region in the processing of acute dental pain. Induced dental pain leads to quantitative changes in brain metabolites within the left insular cortex resulting in significant alterations in metabolites. Negative correlation between subjective pain intensity rating and specific metabolites could be observed.

Endovascular stent treatment for symptomatic benign iliofemoral venous occlusive disease: long-term results 1987-2009.

Venous stenting has been shown to effectively treat iliofemoral venous obstruction with good short- and mid-term results. The aim of this study was to investigate long-term clinical outcome and stent patency. Twenty patients were treated with venous stenting for benign disease at our institution between 1987 and 2005. Fifteen of 20 patients (15 female, mean age at time of stent implantation 38 years [range 18-66]) returned for a clinical visit, a plain X-ray of the stent, and a Duplex ultrasound. Four patients were lost to follow-up, and one patient died 277 months after stent placement although a good clinical result was documented 267 months after stent placement. Mean follow-up after stent placement was 167.8 months (13.9 years) (range 71 (6 years) to 267 months [22 years]). No patient needed an additional venous intervention after stent implantation. No significant difference between the circumference of the thigh on the stented side (mean 55.1 cm [range 47.0-70.0]) compared with the contralateral thigh (mean 54.9 cm [range 47.0-70.0]) (p=0.684) was seen. There was a nonsignificant trend toward higher flow velocities within the stent (mean 30.8 cm/s [range 10.0-48.0]) and the corresponding vein segment on the contralateral side (mean 25.2 cm/s [range 12.0-47.0]) (p=0.065). Stent integrity was confirmed in 14 of 15 cases. Only one stent showed a fracture, as documented on x-ray, without any impairment of flow. Venous stenting using Wallstents showed excellent long-term clinical outcome and primary patency rate.

Ultrasound-guided antegrade femoral access: comparison between the common femoral artery and the superficial femoral artery.

PURPOSE: The aim of this study was to compare ultrasound-guided access of the superficial femoral artery and the common femoral artery. MATERIAL AND METHODS: 100 patients were randomized to ultrasound-guided access either into the SFA or the CFA. The two groups were compared with respect to technical success, access time and complications. In addition, a subgroup analysis was performed to compare the complication rate using manual compression versus closure devices for haemostasis. RESULTS: In the SFA group 49/50 patients were successfully accessed in the assigned location, compared to 41/50 in the CFA group (p = 0.016). The median access time was significantly faster in the SFA group (3 min 25 s) compared to the CFA group (5 min 26 s) (p < 0.001). The most frequent complications in the SFA group were pseudoaneurysms (16.3%) whereas access site haematomas (14.6%) were the most common complication in the CFA group. However, when looking at subgroup with closure devices there was no difference between the SFA group compared to CFA group (p = 1.000). CONCLUSION: Accessing the SFA was more often successful and significantly faster than puncturing the CFA. The pseudoaneurysm rate was higher in the SFA group when using manual compression, but similar when using closure devices.

Compression of the inferior vena cava by the right iliac artery: a rare variant of May-Thurner syndrome.

May-Thurner syndrome is known as compression of the left common iliac vein by the right common iliac artery. We describe a case of an atypical compression of the inferior vena cava by the right common iliac artery secondary to a high aortic bifurcation. Despite an extensive collateral network, there was a significant venous gradient between the iliac veins and the inferior vena cava above the compression. After stenting the venous pressure gradient disappeared. Follow-up 4 months later revealed a good clinical response with a patent stent.

Distribution of neuromedin U binding sites in the rat CNS revealed by in vitro receptor autoradiography.

Neuromedin U (NMU), a neuropeptide implicated in feeding, inflammation, pain control and anxiety-related behaviours, is widely distributed in peripheral organs and the CNS. These effects are thought to be mediated by its receptors NMU(1) and NMU(2). Since its precise sites of interaction in the CNS were to date unknown, we studied the distribution of in vitro binding sites for (125)I-NMU-23 in the rat CNS by receptor autoradiography. High-density specific binding was found in discrete areas of the brain and spinal cord, namely in the limbic system (hippocampal formation, septohippocampal nucleus, indusium griseum, hypothalamus, amygdaloid nuclei), superior colliculus, dorsal raphé, and substantia gelatinosa of the spinal cord. Our findings provide further supportive evidence for a multifunctional role for the peptide in the brain and spinal cord.

Primary stenting of subclavian and innominate artery occlusive disease: a single center's experience.

PURPOSE: To review immediate and midterm results of primary stenting for innominate and subclavian artery occlusive lesions. METHODS: Retrospective data were collected from 48 consecutive symptomatic patients (27 men and 21 women, median age 64 years) having 49 subclavian and innominate artery lesions treated with stenting. Of the patients 52% had concomitant ischemic heart disease, and 30% had carotid and/or vertebral artery disease. Indication for treatment was vertebrobasilar insufficiency (VBI) in 16.6% of the patients; upper limb ischemia (ULI) in 31.3%; VBI and ULI in 12.5%; transient ischemic attack in 16.7%; angina in 12.5% before or after left internal mammary artery-to-coronary artery bypass grafting; and leg claudication in 10.4% before or after axillofemoral bypass grafting. Balloon-expandable stents were used in 44 lesions and self-expandable stents in 5 lesions. In total, 53 stents were placed in 48 patients. RESULTS: Technical success was 96%, and clinical success 94%. We encountered four complications (two puncture site hematomas, one distal hand embolization and one transient cerebral ischemia). Two patients died within 30 days from other causes, and seven patients were lost to follow-up. Mean follow-up time was 16.7 months (range 0.3 to 68.2). Five patients had recurrent lesions treated by surgical (n = 2) or endovascular (n = 3) means. Cumulative primary patency rate was 91.7% and 77% at 12 and 24 months, respectively. Cumulative secondary patency rate was 96.5% and 91.7% at 12 and 24 months, respectively. CONCLUSION: Stenting of subclavian and innominate artery lesions resulted in immediate resolution of patients' symptoms with durable midterm effect and few complications in a larger patient group with serious comorbid conditions.

Inhibitors of the Plasmodium falciparum parasite aspartic protease plasmepsin II as potential antimalarial agents.

Malaria is a very serious infectious disease against which the currently available drugs are loosing effectiveness. The main problem is the emergence and the spreading of resistant parasite strains. New treatments are needed in order to regain control over the disease. Drug discovery efforts towards this goal are likely to be more successful, if they focus towards novel mechanisms of action. Such efforts will result in drugs that are functionally and structurally different from the existing drugs and therefore will overcome existing resistances. Here we focus on the aspartic protease plasmepsin II, which is a promising new drug target. We review the drug discovery efforts that were published in the literature on this enzyme, and we present the compounds synthesized at Actelion Pharmaceuticals Ltd.

Patient's assessment of discomfort during MR arthrography of the shoulder.

PURPOSE: To assess patient discomfort during (a) intraarticular contrast material injection (arthrography) and (b) magnetic resonance (MR) imaging in patients referred for MR arthrography of the shoulder and to compare the relative discomfort associated with each part of the examination. MATERIALS AND METHODS: With use of a visual analogue scale (VAS) and relative ratings, 202 consecutive patients referred for MR arthrography of the shoulder rated the expected discomfort and that actually experienced during both arthrography and MR imaging. The Student t test was used for statistical analysis. RESULTS: The average VAS score (0 = "did not feel anything," 100 = "unbearable") was 16.1 +/- 16.4 (SD) for arthrography and 20.2 +/- 25.0 for MR imaging. This difference was statistically significant (P =.036, paired t test). The discomfort experienced during arthrography was as expected in 90 (44.6%) patients, less than expected in 110 (54.4%), and worse than expected in two (1.0%). MR imaging-related discomfort was as expected in 114 (56.4%) patients, less than expected in 66 (32.7%), and worse in 22 (10.9%). Arthrography was rated worse than MR imaging by 53 (26.2%) patients, equal to MR imaging by 69 (34.2%), and less uncomfortable than MR imaging by 80 (39.6%). CONCLUSION: Arthrography-related discomfort was well tolerated, often less severe than anticipated, and rated less severe than MR imaging-related discomfort.

Osteoid osteoma: technique of computed tomography-controlled percutaneous resection using standard equipment available in most orthopaedic operating rooms.

Symptoms of osteoid osteoma are cured by removing the nidus. 'En-bloc' resection is often not successful because the nidus is hard to find and remove totally. Recently, minimally invasive procedures have been advocated for the resection of osteoid osteoma. Preceding investigators have used a set of special instruments. The nidus is best localized with computed tomography (CT). Surgery under CT control is only possible with minimal invasive procedures. A technique using standard equipment usually available in the operating room can be used successfully for CT-guided removal of the nidus. We report our preliminary results with 17 patients (12 men, 5 women) with an average age of 22 years (range 6-57 years). All patients were pain-free immediately after the operation. The average follow-up was 8.4 months (range 1-22 months) and the average operating time 75 min (range 50-130 min). Ten patients could be treated as outpatients. The average time in hospital after surgery was 1.5 days (range 1-3 days). There were two complications, one superficial wound infection and one change of operative technique to an open procedure due to a technical problem. The diagnosis could be confirmed histologically.

Utility of nonselective abdominal aortography in demonstrating ovarian artery collaterals in patients undergoing uterine artery embolization for fibroids.

PURPOSE: To review the incidence of ovarian collateral supply to uterine fibroids as demonstrated by nonselective abdominal aortography before uterine artery embolization (UAE) and to evaluate the effect of such visualization on interventional management. MATERIALS AND METHODS: The aortograms of 51 consecutive patients (mean age, 42.4 y; range, 30--53 y) undergoing UAE for symptomatic uterine fibroids were reviewed retrospectively for the visualization of ovarian arteries extending into the pelvis. If ovarian arteries were visualized, their size relative to the ipsilateral external iliac artery was measured. Arteries believed large enough to represent a significant blood supply to the uterine fibroids were further evaluated after UAE to determine whether flow persisted. RESULTS: In 13 of 51 patients (25%), a total of 18 ovarian arteries were identified. They were bilateral in five patients and unilateral in eight. Their sizes relative to the ipsilateral external iliac artery ranged from 8% to 57% (mean, 26%). Eight ovarian arteries with a relative size > or = 25% were further evaluated. Five of the eight (62.5%) were not visible after UAE. Of the three persistent ovarian collateral arteries, two were successfully embolized. The patient with the untreated collateral artery experienced persistent menorrhagia. CONCLUSION: Preembolization aortography with the catheter tip at level of the renal arteries demonstrated ovarian collateral arteries in 25% of patients with uterine fibroids. However, their detection influenced treatment in only 6% of the reported cases.

MR arthrography of the glenohumeral joint: two concentrations of gadoteridol versus Ringer solution as the intraarticular contrast material.

PURPOSE: To compare two concentrations of gadoteridol with Ringer solution as the contrast material for magnetic resonance (MR) arthrography of the glenohumeral joint. MATERIALS AND METHODS: One hundred fifty-six consecutive MR arthrograms were randomly obtained with either 2 mmol/L gadoteridol (n = 52), 4 mmol/L gadoteridol (n = 52), or Ringer solution (n = 52). MR arthrograms were assessed quantitatively (for contrast-to-noise ratio [CNR]) and qualitatively (for overall image quality, image contrast, degree of joint distention, and motion artifacts). MR diagnoses were compared with arthroscopic or surgical reports in 88 patients. RESULTS: The mean CNR at imaging was 40.4 with 2 mmol/L gadoteridol, 45.6 with 4 mmol/L gadoteridol, and 48.7 with Ringer solution. The CNR with 2 mmol/L gadoteridol was significantly lower than that with 4 mmol/L gadoteridol (P =.025) and Ringer solution (P =.012). Qualitative differences between the two gadoteridol concentrations were not significant. Ringer solution was significantly worse with regard to overall quality, motion artifacts, image contrast, and joint distention compared with both gadoteridol concentrations. Ringer solution was slightly more sensitive and less specific than the gadoteridol solutions in the detection of supraspinatus tears and less sensitive and more specific in enabling diagnosis of superior labrum anteroposterior lesions. CONCLUSION: MR arthrograms of the shoulder obtained with gadoteridol and those obtained with Ringer solution provided equivalent diagnostic accuracy. The authors, however, preferred the image quality of the gadoteridol-enhanced arthrograms.