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288 result(s) for "Extravasation of Diagnostic and Therapeutic Materials - diagnostic imaging"
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Postprocedural CT for perivertebral cement leakage in percutaneous vertebroplasty is not necessary—results from VERTOS II
Introduction During percutaneous vertebroplasty (PV), perivertebral cement leakage frequently occurs. There is some concern that cement deposits may migrate towards the lungs via the veins during follow-up. We used baseline and follow-up computed tomography (CT) to assess the incidence and extend of late cement migration in a large consecutive patient cohort. Methods VERTOS II is a prospective multicenter randomized controlled trial comparing PV with conservative therapy for osteoporotic vertebral compression fractures (OVCFs). Patients assigned to PV had baseline postprocedural CT scans of the treated vertebral bodies. After a mean follow-up of 22 months, 54 of 78 patients (69%) had follow-up CT. CT scans were analyzed and compared for perivertebral venous, discal, and soft tissue leakage. Results Perivertebral cement leakage occurred in 64 of 80 treated vertebrae (80%; 95% CI, 70% to 87%). All patients remained asymptomatic. Perivertebral venous leakage was present in 56 vertebrae (88%), mostly in the anterior external venous plexus (46 of 56, 82%). Discal leakage occurred in 22 of 64 vertebrae (34%) and soft tissue leakage in two of 64 (4%). Mean injected cement volume in vertebrae with leakage was higher (4.5 versus 3.7 cm 3 , p  = 0.04). Follow-up CT scan showed unchanged perivertebral cement leakages without late cement migration. Conclusion Perivertebral cement leaks during PV for OVCFs occurred frequently in the VERTOS II trial. Cement leakage occurred more frequently with higher injected volumes. However, all patients remained asymptomatic, and late cement migration during follow-up did not occur. Standard postprocedural CT of the treated vertebral body in PV is not necessary.
Intracardiac cement embolism during percutaneous vertebroplasty: incidence, risk factors and clinical management
ObjectiveTo evaluate the incidence and risk factors for ICE during a PV.Materials and methodsSingle-center retrospective analysis of 1512 consecutive patients who underwent 1854 PV procedures for osteoporotic (34 %), malignant (39.9 %) or other cause (26.1 %) of vertebral compression fractures (VCFs)/spine tumor lesions. Only thoracic or lumbar PVs were included. PVs were performed with polymethylmethacrylate (PMMA) low-viscosity bone cement under fluoroscopic guidance. Chest imaging (X-ray or CT) was performed the same day after PV in patients with high clinical suspicion of ICE. All post-procedural chest-imaging examinations were reviewed, and all ICEs were agreed upon in consensus by two radiologists.ResultsICEs were detected in 72 patients (92 cement embolisms). In 86.1 % of the cases, concomitant pulmonary artery cement leakage was detected. Symptomatic ICEs were observed in six cases (8.3% of all ICEs; 0.32% of all PV procedures). No ICE led to death or permanent sequelae. Multiple levels treated during the same PV session were associated with a higher ICE rate [OR: 3.59, 95% CI: (1.98-6.51); p < 0.001]; the use of flat panel technology with a lower ICE occurrence [OR: 0.51, 95% CI: (0.32-0.83); p = 0.007].ConclusionIntracardiac cement embolism after PV has a low incidence (3.9 % in our study). Symptomatic complications related to ICE are rare (0.3%); none was responsible for clinical sequelae in our series.Key Points• The incidence of intracardiac cement embolism (ICE) during PVP is low (3.9%).• Having a high number of treated vertebrae during the same session is a significant risk factor for ICE.• Symptomatic intracardiac cement embolisms have a low incidence (8.3% of patients with ICE).
The role of dual energy CT in differentiating between brain haemorrhage and contrast medium after mechanical revascularisation in acute ischaemic stroke
Objectives To assess the feasibility of dual energy computed tomography (DE-CT) in intra-arterially treated acute ischaemic stroke patients to discriminate between contrast extravasation and intracerebral haemorrhage. Methods Thirty consecutive acute ischaemic stroke patients following intra-arterial treatment were examined with DE-CT. Simultaneous imaging at 80 kV and 140 kV was employed with calculation of mixed images. Virtual unenhanced non-contrast (VNC) images and iodine overlay maps (IOM) were calculated using a dedicated brain haemorrhage algorithm. Mixed images alone, as “conventional CT”, and DE-CT interpretations were evaluated and compared with follow-up CT. Results Eight patients were excluded owing to a lack of follow-up or loss of data. Mixed images showed intracerebral hyperdense areas in 19/22 patients. Both haemorrhage and residual contrast material were present in 1/22. IOM suggested contrast extravasation in 18/22 patients; in 16/18 patients this was confirmed at follow-up. The positive predictive value (PPV) of mixed imaging alone was 25 %, with a negative predictive value (NPV) of 91 % and accuracy of 63 %. The PPV for detection of haemorrhage with DE-CT was 100 %, with an NPV of 89 % and accuracy improved to 89 %. Conclusions Dual energy computed tomography improves accuracy and diagnostic confidence in early differentiation between intracranial haemorrhage and contrast medium extravasation in acute stroke patients following intra-arterial revascularisation. Key Points • Contrast material and haemorrhage have similar density on conventional 120-kV CT. • Contrast material hinders interpretation of CT in stroke patients after recanalisation. • Iodine and haemorrhage have different attenuation at lower kVs. • Dual energy CT improves accuracy in early differentiation of haemorrhage and contrast extravasation. • Early differentiation between iodine and haemorrhage helps to initiate therapy promptly.
CT-based multi-regional radiomics model for predicting contrast medium extravasation in patients with tumors: A case-control study
To develop a non-contrast CT based multi-regional radiomics model for predicting contrast medium (CM) extravasation in patients with tumors. A retrospective analysis of non-contrast CT scans from 282 tumor patients across two medical centers led to the development of a radiomics model, using 157 patients for training, 68 for validation, and 57 from an external center as an independent test cohort. The different volumes of interest from right common carotid artery/right internal jugular vein, right subclavian artery/vein and thoracic aorta were delineated. Radiomics features from the training cohort were used to calculate radiomics scores (Rad scores) and develop radiomics model. Non-contrast CT radiomics features were combined with clinical factors to develop an integrated model. A nomogram was created to visually represent the integration of radiomic signatures and clinical factors. The model's predictive performance and clinical utility were evaluated using receiver operating characteristic (ROC) curve analysis and decision curve analysis (DCA), respectively. Calibration curves were also used to assess the concordance between the model-predicted probabilities and the observed event probabilities. Thirteen radiomics features were selected to determine the Rad score. The radiomic model outperformed the clinical model in the training, validation, and external test cohorts, achieving a greater area under the ROC curve (AUC) with values of 0.877, 0.866, 0.828 compared to the clinical model's 0.852, 0.806, 0.740. The combined model yielded better AUC of 0.945, 0.911, and 0.869 in the respective cohorts. The nomogram identified females, the elderly, individuals with hypertension, long term chemotherapy, radiomic signatures as independent risk factors for CM extravasation in patients with tumors. Calibration and DCA validated the high accuracy and clinical utility of this model. Radiomics models based on multi-regional non-contrast CT image offered improved prediction of CM extravasation compared with clinical model alone.
Comparison of extraarticular leakage values of radiopharmaceuticals used for radionuclide synovectomy
Radionuclide synovectomy is a reliable therapy in patients with chronic synovitis. However, radiation doses delivered to non-target organ systems due to leakage of radioactive material from the articular cavity are an important disadvantage of this procedure. In this study we compared extraarticular leakage values of the 3 commonly used radiopharmaceuticals; 90Y-citrate, 90Y-silicate and 186Re-sulfide colloid. Thirty-five patients with persistent synovitis were enrolled in the study. Twenty-two hemophilic, 8 rheumatoid arthritis and 5 patients with pigmented villonodular synovitis were studied. 90Y labeled silicate and citrate were used for knee joints and 186Re-sulfide for intermediate sized joints. Radiocolloid leakage values were evaluated using a gamma camera with 20% window centered over the bremsstrahlung photopeak of 90Y and a respective window over the 137 keV photopeak of 186Re. Regions of interest were drawn over the injection site, the regional lymph nodes and the background areas. Leakage of radiocolloid was calculated by dividing the counts/pixel in the regional lymph node area to the counts/pixel in the injection site. No visible leakage was observed. The median leakage values calculated for 90Y-citrate, 90Y-silicate and 186Re-sulfide were found as 1.9%, 2.4% and 2.7%, respectively. The difference between the variability of leakage values was not statistically significant (p > 0.05). There was no significant difference in terms of extraarticular leakage between 9Y-citrate, 9Y-silicate and 186Re-sulfide radiocolloids.
Risk factor analyses of contrast leakage and contrast-induced encephalopathy following coil embolization for unruptured intracranial aneurysm
BackgroundContrast-induced encephalopathy (CIE) following endovascular interventions is a rare but serious complication. This study aimed to investigate the risk factors of contrast leakage (CL) and CIE in patients who underwent coil embolization of unruptured intracranial aneurysms (UIAs).MethodsPatients with UIAs who underwent coil embolization at a single tertiary institute between January 2019 and January 2022 were enrolled retrospectively. CL was defined as cortical or subcortical contrast enhancement with effacement of the cortical sulci. CIE was defined as the new onset of neurological deficits associated with CL. Following the procedure, all patients underwent CT scans, and MRI scans were performed on those with symptoms. Patient and procedural risk factors were investigated.ResultsIn total, 459 patients were analyzed. The median procedure time and contrast dose were 69 min and 96 mL, respectively. CL was evident in 35 patients. In the multivariate analysis, hypertension, large aneurysm, longer procedure time, and greater contrast dose were associated with CL. CIE was diagnosed in 19 patients, and the risk factors included large aneurysm, longer procedure time, and greater contrast dose. The procedure time was predictive of both CL (P<0.001) and CIE (P=0.01). The optimal cut-off value for procedure time was 81.5 min. All CIE patients recovered completely within 8–96 hours.ConclusionsA large aneurysm and prolonged procedure time may increase the patient’s risk of CL and CIE due to increased contrast exposure. Patients who underwent a procedure that exceeded 1.5 hours necessitate post-procedure evaluation and monitoring.
Clinical significance of contrast extravasation on computed tomography immediately after thermal ablation for hepatic tumors
Background To evaluate the clinical significance of contrast extravasation observed on post-ablation computed tomography (CT) performed immediately following thermal ablation of hepatic tumors. Methods Between October 2014 and December 2023, 1,274 patients with 1,745 primary or metastatic hepatic tumors underwent ablation, including radiofrequency ablation, microwave ablation, and cryoablation. Among them, 30 patients (median age: 66 years) with contrast extravasation observed on post-ablation CT scans were retrospectively analyzed. The pre- and post-ablation hemoglobin and hematocrit levels were measured. Local tumor progression-free survival (LTPFS) and overall survival (OS) rates were evaluated. Results Among the 30 patients, angiography was performed in 6 patients. Contrast extravasation was observed on angiography in only two patients; contrast extravasation from the right inferior phrenic artery and intercostal artery was noted, and successful transarterial embolization was achieved. Conservative management was considered adequate without additional treatment in 28 of 30 patients. No significant differences were observed between the 1 day before and after ablation hemoglobin (12.9 g/dL; 12.0–13.8 g/dL vs. 12.5 g/dL; 11.5–13.8 g/dL, P  = 0.102) and hematocrit (38.3%; 36.0–40.1% vs. 37.0%; 34.8–39.2%, P  = 0.100) levels. During a mean follow up period of 23.3 ± 17.8 months, the LTPFS rates were 96.4% and 84.3% at 1 and 2 years, respectively. The OS rate after the procedure was 96.7%. Conclusion The presence of contrast extravasation on post-ablation CT was not clinically significant, when extravasation confined to intrahepatic or venous origins. However, transarterial embolization is required if contrast extravasation is detected in the extrahepatic arteries.
Evaluating the risk of extrusion with laser-activated irrigation techniques in root canal systems: a cadaver-based study
Objectives The objective of this study is to evaluate the incidence and volume of contrast medium extrusion when activated with a laser and to compare these outcomes with those of other irrigation techniques. Materials and methods Sixteen cadaver mandibles containing 116 single-rooted teeth were prepared using conventional rotary instrumentation. The teeth were randomly assigned to four irrigation groups: side-vented needle, sonic irrigation, laser activation at the orifice, and laser activation at the middle third of the canal. Gastrografin, an iodinated contrast medium, was used to simulate irrigants. Cone Beam Computed Tomography (CBCT) scans were obtained pre- and post-irrigation to assess the incidence and volume of extrusion. Two blinded observers evaluated the images for the presence or absence of extrusion. Data were statistically analyzed using ANOVA and chi-square tests. Results The observers reached a consensus on 116 out of 116 cases, resulting in a percent agreement of 100%. None of the experimental groups, side-vented needle ( n  = 29), sonic irrigation ( n  = 29), laser activation at the orifice ( n  = 29), and laser activation in the middle third ( n  = 29), demonstrated any radiographic evidence of extrusion. Conclusion This cadaver-based model, combined with CBCT, provides a clinically relevant assessment of irrigant behavior during endodontic treatment. While the findings from this study suggest that LAI at the orifice or in the middle third of the canal may be a safe method for enhancing irrigation in endodontics, clinicians should remain cautious regarding the potential risks of irrigant extrusion. Clinical significance Laser-activated irrigation has the potential to improve debridement and disinfection by enhancing the delivery of irrigants to the apical third of the root canal system. However, clinicians must exercise caution with the depth of laser tip placement to minimize the risk of irrigant extrusion. The cadaver-based model used in this study offers valuable insights into real-world clinical conditions and can serve as an effective tool for evaluating irrigation techniques in future research.
Role of urgent contrast-enhanced multidetector computed tomography for acute lower gastrointestinal bleeding in patients undergoing early colonoscopy
Background The clinical significance of performing computed tomography (CT) for acute lower gastrointestinal bleeding (LGIB) remains unknown. This study aimed to evaluate the role of urgent CT in acute LGIB settings. Methods The cohort comprised 223 patients emergently hospitalized for LGIB who underwent early colonoscopy within 24 h of arriving at the hospital, including 126 who underwent CT within 3 h of arrival. We compared the bleeding source rate between two strategies: early colonoscopy following urgent CT or early colonoscopy alone. Results No significant differences in age, sex, comorbidities, vital signs, or laboratory data were observed between the strategies. The detection rate was higher with colonoscopy following CT for vascular lesions (35.7 vs. 20.6 %, p  = 0.01), leading to more endoscopic therapies (34.9 vs. 13.4 %, p  < 0.01). Of the 126 who underwent colonoscopy following CT, 26 (20.6 %) had extravasation and 34 (27.0 %) had nonvascular findings. The sensitivity and specificity of CT extravasation and nonvascular findings for predicting vascular lesions and inflammation or tumors were 37.8 and 88.9 and 81.3 and 80.9 %, respectively. A high κ agreement (0.83, p  < 0.01) for active bleeding locations was found between CT and subsequent colonoscopy. There were no cases of contrast-induced nephropathy after 1 week of CT. Conclusions Urgent CT before colonoscopy had about 15 % additional value for detecting vascular lesion compared to colonoscopy alone and thus enabled subsequent endoscopic therapies. Contrast-enhanced CT in acute LGIB settings was safe and correctly identified the presence and location of active bleeding, as well as severe inflammation or tumor stenosis, facilitating decision making.
Clinical management of active bleeding: what the emergency radiologist needs to know
Active bleeding is a clinical emergency that often requires swift action driven by efficient communication. Extravasation of intravenous (IV) contrast on computed tomography (CT) is a hallmark of active hemorrhage. This can be seen on exams performed for a variety of indications and can occur anywhere in the body. As both traumatic and non-traumatic etiologies of significant blood loss are clinical emergencies, exams demonstrating active bleeding are often performed in emergency departments and read by emergency radiologists. Prompt communication of these findings to the appropriate emergency medicine and surgical providers is crucial. Although many types of active hemorrhage can be managed by interventional radiology techniques, endoscopic and surgical management or clinical observation may be appropriate in certain cases. To facilitate optimal care, it is important for emergency radiologists to understand the scope of indications for embolization of bleeding by interventional radiologists (IR) and when an IR consultation is warranted. Similarly, timely comprehensive diagnostic radiology reporting including pertinent positive and negative findings tailored for IR colleagues can expedite the appropriate intervention.