Non-ischemic cerebral enhancing (NICE) lesions after flow diversion for intracranial aneurysms: a multicenter study.

BACKGROUND: Non-ischemic cerebral enhancing (NICE) lesions have been reported as a rare complication of various neuroendovascular procedures, but information on their incidence after flow diversion is scant. It is unclear if specific devices or novel coating technologies may impact their occurrence. METHODS: We conducted a multicenter study on the incidence of NICE lesions after flow diverter (FD) implantation for cerebral aneurysm treatment. RESULTS: Eight centers identified 15 patients and provided detailed data. The clinical presentation ranged from asymptomatic to hemiplegia and cognitive impairment. The mean time to diagnosis after treatment was 65.1±101.5 days. Five centers disclosed information on all of their 1201 FD procedures during the inclusion period (2015-2022), during which 12 patients were diagnosed with NICE lesions in these institutions-that is, an incidence of 1%. FD coatings did not increase the incidence (6/591 patients (1%) treated with surface-modified FD vs 6/610 patients (1%) treated with bare FD; P=1.00). Significantly increased rates of 3.7% (6 cases in 161 procedures; P<0.01) and 3.3% (5 cases in 153 procedures; P<0.01) were found with stents of two specific product lines. The use of one product line was associated with a significantly lower incidence (0 cases in 499 procedures (0%); P<0.01). CONCLUSIONS: Novel stent coatings are not associated with an increased incidence of NICE lesions. The incidence rate of 1% suggests that these lesions may occur more often after flow diversion than after other endovascular treatments. We found a concerning accumulation of NICE lesion cases when FDs from two product families were used.

Value of high-field magnetic resonance imaging for diagnosis and classification of acute colonic diverticulitis.

OBJECTIVES: Due to limited and outdated literature, the role of magnetic resonance imaging (MRI) in the diagnostic work-up of acute colonic diverticulitis (ACD) is still under debate. The purpose of this study was to compare the performance of modern high-field MRI and multidetector computed tomography (MDCT) in the diagnosis and classification of ACD. METHODS: In our prospective study 24 emergency patients with the clinical diagnosis of ACD received MDCT and high-field MRI. Imaging features of ACD were assessed and categorized according to the classification of diverticular disease (CDD) by three independent readers. Results were matched with the final clinical report. RESULTS: MRI with a specialized examination protocol clearly depicted all relevant findings of ACD. Statistical analysis resulted in an almost perfect strength of agreement between CT and MRI across all readers for the final CDD category (κ = 0.94) and the stage-related image features (κ = 0.98). Moderate agreement was seen for the detection of micro-abscesses (κ = 0.78), with a slight advantage for MRI. CONCLUSION: Modern high-field MRI is fully comparable to MDCT in the assessment of ACD and has the potential to serve as a first-line imaging tool.

Respiratory motion artefacts in Gd-EOB-DTPA (Primovist/Eovist) and Gd-DOTA (Dotarem)-enhanced dynamic phase liver MRI after intensified and standard pre-scan patient preparation: A bi-institutional analysis.

OBJECTIVE: The objective of this study is to evaluate if intensified pre-scan patient preparation (IPPP) that comprises custom-made educational material on dynamic phase imaging and supervised pre-imaging breath-hold training in addition to standard informative conversation with verbal explanation of breath-hold commands (standard pre-scan patient preparation-SPPP) might reduce the incidence of gadoxetate disodium (Gd-EOB-DTPA)-related transient severe respiratory motion (TSM) and severity of respiratory motion (RM) during dynamic phase liver MRI. MATERIAL AND METHODS: In this bi-institutional study 100 and 110 patients who received Gd-EOB-DTPA for dynamic phase liver MRI were allocated to either IPPP or SPPP at site A and B. The control group comprised 202 patients who received gadoterate meglumine (Gd-DOTA) of which each 101 patients were allocated to IPPP or SPPP at site B. RM artefacts were scored retrospectively in dynamic phase images (1: none- 5: extensive) by five and two blinded readers at site A and B, respectively, and in the hepatobiliary phase of the Gd-EOB-DTPA-enhanced scans by two blinded readers at either site. RESULTS: The incidence of TSM was 15% at site A and 22.7% at site B (p = 0.157). IPPP did not reduce the incidence of TSM in comparison to SPPP: 16.7% vs. 21.6% (p = 0.366). This finding was consistent at site A: 12% vs. 18% (p = 0.401) and site B: 20.6% vs. 25% (p = 0.590). The TSM incidence in patients with IPPP and SPPP did not differ significantly between both sites (p = 0.227; p = 0.390). IPPP did not significantly mitigate RM in comparison to SPPP in any of the Gd-EOB-DTPA-enhanced dynamic phases and the hepatobiliary phase in patients without TSM (all p≥0.072). In the Gd-DOTA control group on the other hand, IPPP significantly mitigated RM in all dynamic phases in comparison to SPPP (all p≤0.031). CONCLUSIONS: We conclude that Gd-EOB-DTPA-related TSM cannot be mitigated by education and training and that Gd-EOB-DTPA-related breath-hold difficulty does not only affect the subgroup of patients with TSM or exclusively the arterial phase as previously proposed.

Misplacement of a Port Catheter: A Differentiated View.

Clinical radiological controls after the insertion of central venous catheters (CVC) are of high importance. Misplacement of the CVC, outside of large vessels, as described in our first case, occurs in more than 7% of cases and may be associated with life-threatening events. A persistent left-sided superior vena cava (PLSSVC) occurs in 0.3-0.5% of the standard population. In one of the cases a CT scan of the chest showed the catheter in a PLSSVC. Neoadjuvant radiochemotherapy was indicated in a patient with an adenocarcinoma of the oesophagus. Under hospitalised monitoring, full-dose chemotherapy was given. Consequences for the patients arise when the findings are known for future interventions. If a PLSSVC is expected and a CVC is to be inserted, the venous return to the heart should be evaluated first, to preclude a possible backflow to the left atrium. With this constellation, a right-to-left shunt can be expected in in 10% of cases. Affected patients face a high risk of developing cardioembolic events.

Improvement of Contrast Media Enhancement in CTA Evaluating Pulmonary Embolism by Utilizing 'Delayed' Bolus Tracking in the Descending Aorta.

BACKGROUND: As standard bolus triggering in the pulmonary trunk sometimes fails to achieve sufficient enhancement in the pulmonary arteries, the study investigates an alternative, 'delayed' position of the tracking ROI in the descending aorta. MATERIAL/METHODS: Retrospective analysis of 143 patients suspected of pulmonary embolism investigated with 3 different scanners (16 to 80 rows) in clinical routine. Bolus triggering with 120 hounsfield units (HU) was performed using the pulmonary trunk (n=70) or descending aorta (n=73) after application of 70 to 120 mL of contrast agent, Iomeprol 300. Student's t-test was applied to compare vascular enhancement. Additional factors were analysed by a regression analysis. RESULTS: Positioning of the tracking ROI in the descending aorta achieved a significantly higher contrast enhancement in the pulmonary trunk with a mean increase of 63 HU (p<0.001). CONCLUSIONS: In CTA, delayed acquisition by using the descending aorta for bolus triggering can improve the enhancement of the pulmonary trunk to investigate a pulmonary embolism. Furthermore, the scan protocol simultaneously allows to rule out aortic pathologies as an alternative cause for a similar clinical condition.

Bipolar radiofrequency ablation of spinal tumors: predictability, safety and outcome.

BACKGROUND: Bone metastases are often the cause of tumor-associated pain and reduction of quality of life. For patients that cannot be treated by surgery, a local minimally invasive therapy such as radiofrequency ablation can be a useful option. In cases in which tumorous masses are adjacent to vulnerable structures, the monopolar radiofrequency can cause severe neuronal damage because of the unpredictability of current flow. PURPOSE: The aim of this study is to show that the bipolar radiofrequency ablation provides an opportunity to safely treat such spinal lesions because of precise predictability of the emerging ablation zone. STUDY DESIGN: Prospective cohort study of 36 patients undergoing treatment at a single institution. PATIENT SAMPLE: Thirty-six patients in advanced tumor stage with primary or secondary tumor involvement of spine undergoing radiofrequency ablation. OUTCOME MEASURES: Prediction of emerging ablation zone. Clinical outcome of treated patients. METHODS: X-ray-controlled treatment of 39 lesions by bipolar radiofrequency ablation. Magnetic resonance imaging was performed pre- and postinterventionally. Patients were observed clinically during their postinterventional stay. RESULTS: The extent of the ablation zones was predictable to the millimeter because it did not cross the peri-interventional planned dorsal and ventral boundaries in any case. No complications were observed. CONCLUSIONS: Ablation of tumorous masses adjacent to vulnerable structures is feasible and predictable by using the bipolar radiofrequency ablation. Damage of neuronal structures can be avoided through precise prediction of the ablation area.

Immunocompetent young man with cerebral abscess and cortical venous infarction mimicking cerebritis caused by Gemella morbillorum.

Gemella morbillorum is an anaerobic gram-positive diplococcus and in most cases a harmless commensal, which occasionally causes infections in the central nervous system. We report on an immunocompetent young man with focal neurological symptoms and cephalgia caused by a cerebral abscess. Although successful treatment was done with neurosurgical intervention and antibiotic therapy, he suffered from a venous infarction 5 weeks after first diagnosis, which mimicked cerebritis as an early stage of relapsing abscess. Imaging and investigation of cerebrospinal fluid was necessary for sufficient differential diagnosis and antibiotic therapy could be stopped after altogether 8 weeks of treatment. In summary, G morbillorum causes not only biphasic infections, but also can be accompanied by infarction in the central nervous system despite sufficient antibiotic therapy.

Bipolar radio frequency ablation of spinal neoplasms in late stage cancer disease: a report of three cases.

STUDY DESIGN: Case report. OBJECTIVE: To avoid neuronal damage by using the bipolar radio frequency ablation of spinal tumors. SUMMARY OF BACKGROUND DATA: Radio frequency ablation of tumorous masses is an established procedure and is increasingly used as pain therapy of unresectable spine tumors. Ablation of lesions adjacent to vulnerable structures remains a challenging task because flow of current is insufficiently controlled by monopolar probes. Using this technique, a prediction of the induced necrosis accurate to the millimeter is not feasible. METHODS: Three patients with metastases of the spine were treated using the bipolar radio frequency ablation. RESULTS: In all 3 cases collateral damage of neuronal structures could be avoided even though tumorous masses touched the cauda equina or were very close to vulnerable structures, respectively. The induction of necrosis was predictable to the millimeter. CONCLUSION: Ablation of tumorous masses adjacent to neural structures by bipolar technique, is feasible and predictable. Spinal cord damage can be avoided by exact planning of the induced necrosis.