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1.
J Vasc Interv Radiol ; 34(2): 244-252.e1, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36241152

RESUMEN

PURPOSE: To prove the utility of magnetic resonance (MR) imaging response as a surrogate end point of treatment efficacy and survival after yttrium-90 transarterial radioembolization (TARE) for colorectal liver metastases (CRLMs), and to investigate whether outcomes can be predicted at baseline using MR imaging or clinical variables. MATERIALS AND METHODS: A total of 50 (135) patients with TARE for CRLMs between August 2008 and January 2020 and peri-interventional MR imaging within defined timeframes were included for tumor segmentation. Pretreatment and posttreatment target tumor volumes were measured according to the volumetric Response Evaluation Criteria In Solid Tumors (vRECIST) and the quantitative European Association for the Study of the Liver (qEASL) criteria. Cox regression models were used to analyze the impact of MR morphologic response, vascularity at baseline, and clinical variables on patient survival. Logistic regression analyses were used to evaluate the predictors of MR morphologic response at baseline. RESULTS: The median survival was 337 days (95% confidence interval [CI], 243-431). As opposed to the vRECIST, the application of the qEASL criteria 3 months after the treatment allowed for a significant (P < .05) separation of the survival curves for partial response, stable disease, and progressive disease with a median survival of 412 days (95% CI, 57-767) in responders. High tumor burden and technetium-99m lung shunt significantly decreased the probability of survival. MR morphologic response was not predictable at baseline using imaging or clinical data. CONCLUSIONS: MR response according to the qEASL criteria outperformed the vRECIST in measuring the biologic impact of TARE and predicting patient survival. Baseline contrast enhancement did not predict MR response to treatment, which may reflect elevated dose requirements in tumors with a high proportion of viable tumor volume.


Asunto(s)
Neoplasias Colorrectales , Embolización Terapéutica , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/patología , Radioisótopos de Itrio/efectos adversos , Embolización Terapéutica/métodos , Imagen por Resonancia Magnética/métodos , Resultado del Tratamiento , Neoplasias Colorrectales/patología , Estudios Retrospectivos
2.
Eur Radiol ; 32(7): 4687-4698, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35230518

RESUMEN

OBJECTIVES: This study aims to better characterize potential responders of Y-90-radioembolization at baseline through analysis of clinical variables and contrast enhanced (CE) MRI tumor volumetry in order to adjust therapeutic regimens early on and to improve treatment outcomes. METHODS: Fifty-eight HCC patients who underwent Y-90-radioembolization at our center between 10/2008 and 02/2017 were retrospectively included. Pre- and post-treatment target lesion volumes were measured as total tumor volume (TTV) and enhancing tumor volume (ETV). Survival analysis was performed with Cox regression models to evaluate 65% ETV reduction as surrogate endpoint for treatment efficacy. Univariable and multivariable logistic regression analyses were used to evaluate the combination of baseline clinical variables and tumor volumetry as predictors of ≥ 65% ETV reduction. RESULTS: Mean patients' age was 66 (SD 8.7) years, and 12 were female (21%). Sixty-seven percent of patients suffered from liver cirrhosis. Median survival was 11 months. A threshold of ≥ 65% in ETV reduction allowed for a significant (p = 0.04) separation of the survival curves with a median survival of 11 months in non-responders and 17 months in responders. Administered activity per tumor volume did predict neither survival nor ETV reduction. A baseline ETV/TTV ratio greater than 50% was the most important predictor of arterial devascularization (odds ratio 6.3) in a statistically significant (p = 0.001) multivariable logistic regression model. The effect size was strong with a Cohen's f of 0.89. CONCLUSION: We present a novel approach to identify promising candidates for Y-90 radioembolization at pre-treatment baseline MRI using tumor volumetry and clinical baseline variables. KEY POINTS: • A decrease of 65% enhancing tumor volume (ETV) on follow-up imaging 2-3 months after Y-90 radioembolization of HCC enables the early prediction of significantly improved median overall survival (11 months vs. 17 months, p = 0.04). • Said decrease in vascularization is predictable at baseline: an ETV greater than 50% is the most important variable in a multivariable logistic regression model that predicts responders at a high level of significance (p = 0.001) with an area under the curve of 87%.


Asunto(s)
Carcinoma Hepatocelular , Embolización Terapéutica , Neoplasias Hepáticas , Anciano , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/radioterapia , Embolización Terapéutica/métodos , Femenino , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/radioterapia , Masculino , Selección de Paciente , Estudios Retrospectivos , Resultado del Tratamiento , Radioisótopos de Itrio/uso terapéutico
3.
J Vasc Interv Radiol ; 31(5): 720-727, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32127321

RESUMEN

PURPOSE: To quantify the occurrence of tumor seeding in computed tomography (CT)-guided high-dose-rate brachytherapy (HDRBT) and to identify potential risk factors. MATERIALS AND METHODS: CT-HDRBT is a minimally invasive therapeutic option for local ablation of unresectable tumors. The procedure involves CT-guided placement of an enclosed catheter and high-dose-rate brachytherapy using iridium-192. Transcutaneous puncture of a tumor with subsequent retraction of the applicator has the potential risk of tumor seeding along the puncture tract. A total of 1,765 consecutive CT-HDRBT procedures were performed at this center between 2006 and 2017 and were retrospectively analyzed. In addition, a distinction was made between whether the puncture tract was irradiated or not. Follow-up imaging datasets were evaluated for tumor seeding along the former puncture tracts. Descriptive and exploratory statistical analyses of the data were performed. RESULTS: Tumor seeding was observed in 25 cases (25 of 1,765 cases [1.5%]). A total of 0.008 cases occurred per person-age. Patient age was identified as a potential risk factor with an odds ratio of 1.046 (95% confidence interval, 1.003-1.091; P = .04). There were no differences between whether the puncture tract was irradiated or not (P = .552). CONCLUSIONS: Tumor seeding along the puncture tract can occur in CT-HDRBT but is rare.


Asunto(s)
Braquiterapia , Neoplasias del Sistema Digestivo/radioterapia , Radioisótopos de Iridio/administración & dosificación , Siembra Neoplásica , Dosis de Radiación , Exposición a la Radiación , Radiografía Intervencional , Radiofármacos/administración & dosificación , Tomografía Computarizada por Rayos X , Factores de Edad , Anciano , Braquiterapia/efectos adversos , Neoplasias del Sistema Digestivo/diagnóstico por imagen , Neoplasias del Sistema Digestivo/patología , Femenino , Humanos , Radioisótopos de Iridio/efectos adversos , Masculino , Persona de Mediana Edad , Punciones , Exposición a la Radiación/efectos adversos , Radiografía Intervencional/efectos adversos , Radiofármacos/efectos adversos , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Tomografía Computarizada por Rayos X/efectos adversos , Resultado del Tratamiento
4.
Acta Radiol ; 61(10): 1421-1430, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32122149

RESUMEN

BACKGROUND: In computed tomography (CT) scans, artifacts caused by metallic orthopedic implants still hamper the visualization of important, periprosthetic tissues. Smart MAR metal artifact reduction tool is a promising three-stage, projection-based, post-processing algorithm. PURPOSE: To determine whether the Smart MAR tool improves subjective and objective image quality and diagnostic confidence in patients with orthopedic implants of the hip, spine, and shoulder. MATERIAL AND METHODS: Seventy-two patients with orthopedic screws, hip/shoulder replacement, or spine spondylodesis were included. CT scans were performed on a single-source multislice CT scanner, raw data were post-processed using Smart MAR. Image quality was evaluated both quantitatively (ROI-based) and qualitatively (rater-based) and compared to iterative reconstructions (ASIR V). As comparative standard for artificial prosthetic breaks or loosening, follow-up examinations were used. RESULTS: Smart MAR reconstructions of the hip (n = 23), spine (n = 26), and shoulder (n = 23) showed a significantly reduced attenuation and noise of regions adjacent to metallic implants (P<0.002). Subjective image quality (P<0.005, shoulder P = 0.038/P = 0.046) and overall diagnostic confidence were higher in Smart MAR (all regions P<0.002). Signal-to-noise ratio (SNR; P = 0.72/P = 0.96) was not improved. Compared to standard ASIR V new, artificial metal extinctions (up to 50%) or periprosthetic hem lines (48%-73%) were introduced by Smart MAR. CONCLUSION: Smart MAR improved image quality of the hip, spine, and shoulder CT scans resulting in higher diagnostic confidence in evaluation of periprosthetic soft tissues. As shown for spine implants, it should be used with caution and as a complementary tool for evaluation of periprosthetic loosening or integrity of metal implant, as in many cases it introduced new artifacts.


Asunto(s)
Cadera/diagnóstico por imagen , Prótesis e Implantes , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Hombro/diagnóstico por imagen , Columna Vertebral/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Anciano , Artefactos , Femenino , Humanos , Masculino , Metales , Persona de Mediana Edad , Dosis de Radiación , Relación Señal-Ruido
5.
Acta Radiol ; 61(7): 936-944, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31698929

RESUMEN

BACKGROUND: Process optimization in computed tomography (CT) and telemedicine. PURPOSE: To compare image quality and objective diagnostic accuracy of medical-grade and consumer-grade digital displays/computer terminals for detection of intracranial aneurysms. MATERIAL AND METHODS: Four radiologists with different levels of experience retrospectively read a total of 60 patients including 30 cases of proven therapy-naïve intracranial aneurysm detectable on a medical-grade grayscale calibrated display. They had 5 min per case reading the first 20 datasets using only axial slices, the next 20 patients using axial slices and multiplanar reconstructions (MPRs), and the last 20 patients using axial slices, MPRs, and maximum intensity projections (MIPs). Three months after the first reading session on a medical-grade display, they read all datasets again under the same standardized conditions but on a consumer-grade display. Diagnostic performance, subjective diagnostic confidence, and reading speed were analyzed and compared. Readers rated image quality on a five-point Likert scale. RESULTS: Diagnostic accuracy did not differ significantly with areas under the curve of 0.717-0.809 for all readers on both display devices. Sensitivity and specificity did not increase significantly when adding MPRs and/or MIPs. Reading speed was similar with both devices. There were no significant differences in subjective image quality scores, and overall inter-reader variability of all subjective parameters correlated positively between the two devices (P <0.001-0.011). CONCLUSION: Diagnostic accuracy and readers' diagnostic confidence in detecting and ruling out intracranial aneurysm were similar on commercial-grade and medical-grade displays. Additional reconstructions did not increase sensitivity/specificity or reduce the time needed for diagnosis.


Asunto(s)
Presentación de Datos/normas , Procesamiento de Imagen Asistido por Computador/métodos , Aneurisma Intracraneal/diagnóstico por imagen , Evaluación de Procesos, Atención de Salud , Telemedicina/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Femenino , Humanos , Yohexol/análogos & derivados , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
6.
Acta Radiol ; 60(4): 425-432, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29950111

RESUMEN

BACKGROUND: Virtual monochromatic images (VMI) generated using spectral computed tomography (CT) are promising recently available tools to improve diagnostic performance in oncologic patients. PURPOSE: To investigate if virtual monochromatic datasets are suitable for clinical routine use in patients with hypervascularized abdominal tumors. MATERIAL AND METHODS: A total of 41 patients with hypervascularized hepatocellular carcinoma (HCC), renal cell carcinoma (RCC), or neuroendocrine tumors (NET) were enrolled in the study; 451 CT series were analyzed. In an intra-individual study design, virtual monochromatic datasets of the arterial phase of each scan were computed. Image quality was assessed objectively by determining signal-to-noise ratio (SNR) and contrast-to-noise ratios (CNR) and subjectively by using five-point Likert-scales. The volume CT dose index (CTDIvol) was taken from each radiation dose report. The increase in reading time was estimated from the increase in the number of images. RESULTS: Intra-individual comparison of the spectral mode in the arterial phase with the portal venous phase revealed no significant increase in the applied dose. SNR, CNRtumor-to-liver , and CNRtumor-to-muscle were significantly increased by lowering virtual monochromatic energy. Subjective image quality scores revealed an increase of contrast in low energy datasets, resulting in significantly higher diagnostic confidence, but an increased image noise at low energies. While diagnostic confidence improved, taking all datasets into account resulted in a significantly longer estimated reading time. CONCLUSION: In clinical practice, the use of low energy VMI improved diagnostic confidence without a significant increase in dose. The main disadvantage is a decrease in efficiency due to longer reading times.


Asunto(s)
Neoplasias Abdominales/diagnóstico por imagen , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Neuroendocrino/diagnóstico por imagen , Carcinoma de Células Renales/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Neoplasias Abdominales/irrigación sanguínea , Anciano , Carcinoma Hepatocelular/irrigación sanguínea , Carcinoma Neuroendocrino/irrigación sanguínea , Carcinoma de Células Renales/irrigación sanguínea , Femenino , Humanos , Hígado/irrigación sanguínea , Hígado/diagnóstico por imagen , Neoplasias Hepáticas/irrigación sanguínea , Masculino , Persona de Mediana Edad , Neovascularización Patológica/diagnóstico por imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Relación Señal-Ruido , Estómago/irrigación sanguínea
7.
Acta Radiol ; 59(11): 1316-1325, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29430936

RESUMEN

Background Endovascular aneurysm repair (EVAR) requires lifelong surveillance by computed tomography angiography (CTA). This is attended by a substantial accumulation of radiation exposure. Iterative reconstruction (IR) has been introduced to approach dose reduction. Purpose To evaluate adaptive statistical iterative reconstruction (ASIR) at different levels of tube voltage concerning image quality and dose reduction potential in follow-up post EVAR. Material and Methods One hundred CTAs in 67 patients with EVAR were examined using five protocols: protocol A (n = 40) as biphasic standard using filtered back projection (FBP) at 120 kV; protocols B (n = 40), C (n = 10), and D1 (n = 5) biphasic using ASIR at 120, 100, and 80 kV, respectively; and protocol D2 (n = 5) with a monophasic splitbolus ASIR protocol at 80 kV. Image quality was assessed quantitatively and qualitatively. Applied doses were determined. Results Applied doses in ASIR protocols were significantly lower than FBP standard (up to 75%). Compared to protocol A, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) (e.g. arterial CNR intra-/extra-stent lumen: A = 35.4 ± 13.5, B = 34.2 ± 10.0, C = 29.6 ± 6.8, D1 = 32.1 ± 6.3, D2 = 40.8 ± 23.1) in protocol B were equal and in protocols C and D equal to partially inferior, however not decisive for diagnostic quality. Subjective image quality ratings in all protocols were good to excellent without impairments of diagnostic confidence (A-D2: 5), with high inter-rater agreement (60-100%). Conclusion ASIR contributes to significant dose reduction without decisive impairments of image quality and diagnostic confidence. We recommend an adapted follow-up introducing ASIR and combined low-kV in the long-term surveillance after EVAR.


Asunto(s)
Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/cirugía , Angiografía por Tomografía Computarizada/métodos , Procedimientos Endovasculares/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Dosis de Radiación , Anciano , Aorta Abdominal/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Complicaciones Posoperatorias/diagnóstico por imagen , Estudios Prospectivos , Reproducibilidad de los Resultados , Resultado del Tratamiento
8.
J Comput Assist Tomogr ; 41(4): 668-674, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28099226

RESUMEN

OBJECTIVE: The aim of the study was to evaluate the impact of iterative reconstruction (IR) and low-kilovolt technique on dose reduction and image quality of chest computed tomography scans obtained in patients with cystic fibrosis (CF). METHODS: A total of 124 CF patients were examined; group A (n = 63) was examined with a dose reduction protocol using IR and group B (n = 61) with a standard protocol using filtered back projection. Further subgroups with tube voltage modulations were established. Quantitative and qualitative image quality was assessed. RESULTS: The radiation dose in groups with comparable image quality was approximately 40% lower using IR compared with filtered back projection. The IR protocol combined with 80-kV tube voltage showed adequate image quality with a mean effective dose of only 0.47 mSv. CONCLUSIONS: Iterative reconstruction helps extensively reduce radiation dose by improving image quality. It permits the use of low-kilovolt protocols without significantly degrading image reading ability in the monitoring of the predominantly young patients with CF.


Asunto(s)
Fibrosis Quística/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Dosis de Radiación , Tomografía Computarizada por Rayos X/métodos , Adulto , Femenino , Humanos , Pulmón/diagnóstico por imagen , Masculino , Adulto Joven
9.
Acta Radiol ; 57(3): 362-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25852193

RESUMEN

BACKGROUND: Rising numbers of computed tomography (CT) examinations worldwide have led to a focus on dose reduction in the latest developments in CT technology. Iterative reconstruction (IR) models bear the potential to effectively reduce dose while maintaining adequate image quality. PURPOSE: To assess the impact of adaptive statistical iterative reconstruction (ASIR) technique on dose reduction and image quality in a dedicated whole body CT (WBCT) protocol for trauma patients. MATERIAL AND METHODS: A total of 122 subjects with multiple trauma was prospectively included in our study. Subjects who had to undergo a WBCT following a severe trauma were randomly assigned to two different groups: Group A was examined with an ASIR protocol for the body series (n = 64), group B (n = 58) was examined using a standard filtered back projection (FBP) protocol. Image quality was assessed both quantitatively by calculating signal-to-noise ratio (SNR) and contrast-to-noise ratios (CNRs) and qualitatively by two observers who evaluated image quality using a 5-point scale system. Applied dose was analyzed as CTDIvol (mGy), total DLP (mGyxcm), and effective dose (mSv). RESULTS: Applied dose for the body series in group A was about 23% lower than in group B (P < 0.05). SNR and CNRs for different tissues were not significantly different. Subjective image quality ratings were excellent and showed no significant difference, with a high inter-reader agreement. CONCLUSION: ASIR contributes to a relevant dose reduction without any loss of image quality in a dedicated WBCT protocol for patients with multiple trauma.


Asunto(s)
Traumatismo Múltiple/diagnóstico por imagen , Dosis de Radiación , Exposición a la Radiación/estadística & datos numéricos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Imagen de Cuerpo Entero/métodos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Estudios Prospectivos , Reproducibilidad de los Resultados , Relación Señal-Ruido
11.
Cardiovasc Intervent Radiol ; 47(8): 1025-1036, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38884781

RESUMEN

This CIRSE Standards of Practice document is aimed at interventional radiologists and provides best practices for performing liver regeneration therapies prior to major hepatectomies, including portal vein embolization, double vein embolization and liver venous deprivation. It has been developed by an expert writing group under the guidance of the CIRSE Standards of Practice Committee. It encompasses all clinical and technical details required to perform liver regeneration therapies, revising the indications, contra-indications, outcome measures assessed, technique and expected outcomes.


Asunto(s)
Embolización Terapéutica , Venas Hepáticas , Regeneración Hepática , Vena Porta , Humanos , Vena Porta/diagnóstico por imagen , Embolización Terapéutica/métodos , Venas Hepáticas/diagnóstico por imagen , Hepatectomía/métodos , Radiografía Intervencional , Hígado/irrigación sanguínea , Hígado/diagnóstico por imagen
12.
Eur J Surg Oncol ; 50(7): 108429, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38788357

RESUMEN

PURPOSE: To assess the efficacy and safety of computed tomography (CT)-guided high-dose-rate HDR) brachytherapy in treating recurrent hepatocellular carcinoma (HCC) not amenable to repeated resection or radiofrequency ablation. MATERIALS AND METHODS: From January 2010 to January 2022, 38 patients (mean age, 70.1 years; SD ± 9.0 years) with 79 nodular and four diffuse intrahepatic HCC recurrences not amenable to repeated resection or radiofrequency ablation underwent CT-guided HDR brachytheapy in our department. Tumor response was evaluated by cross-sectional imaging 6 weeks after CT-guided HDR brachytherapy and every 3 months thereafter. Local tumor control (LTC), progression-free survival (PFS) and overall survival (OS) were assessed using Kaplan-Meier curves (KPCs). Severity of procedure-related complications (PRCs) was classified as recommended by the Society of Interventional Radiology (SIR). RESULTS: Patients were available for MRI evaluation for a mean follow-up of 33.1 months (SD, ±21.6 mm, range 4-86 months; median 29 months). Patients had a mean of 2.3 (SD, ±1.4) intrahepatic tumors. Mean tumor diameter was 43.2 mm (SD, ±19.6 mm). 13 of 38 (34.2%) patients showed local tumor progression after CT-guided HDR brachytherapy. Mean LTC was 29.3 months (SD, ±22.1). Distant tumor progression was seen in 12 patients (31.6%). The mean PFS was 20.8 months (SD, ±22.1). Estimated 1-, 3-, and 5-year PFS rates were 65.1%, 35.1% and 22.5%, respectively. 13 patients died during the follow-up period. Mean OS was 35.4 months (SD, ±21.7). Estimated 1-, 3-, and 5-year OS rates were 91.5%, 77.4% and 58.0%, respectively. SIR grade 1 complications were recorded in 8.6% (5/38) and SIR grade 2 complications in 3.4% (2/58) of interventions. CONCLUSION: CT-guided HDR brachytherapy is a safe and efficient therapeutic option for managing large or critically located HCC recurrences in the remaining liver after prior hepatic resection.


Asunto(s)
Braquiterapia , Carcinoma Hepatocelular , Neoplasias Hepáticas , Recurrencia Local de Neoplasia , Tomografía Computarizada por Rayos X , Humanos , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/patología , Braquiterapia/métodos , Carcinoma Hepatocelular/radioterapia , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Anciano , Masculino , Femenino , Persona de Mediana Edad , Radioterapia Guiada por Imagen/métodos , Ablación por Radiofrecuencia/métodos , Anciano de 80 o más Años , Estudios Retrospectivos , Dosificación Radioterapéutica , Tasa de Supervivencia , Supervivencia sin Progresión
13.
Sci Rep ; 14(1): 16399, 2024 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-39014057

RESUMEN

Metal artifacts notoriously pose significant challenge in computed tomography (CT), leading to inaccuracies in image formation and interpretation. Artifact reduction tools have been designed to improve cone beam computed tomography (CBCT) image quality by reducing artifacts caused by certain high-density materials. Metal artifact reduction (MAR) tools are specific algorithms that are applied during image reconstruction to minimize or eliminate artifacts degrading CBCT images. The purpose of the study is to evaluate the effect of a MAR algorithm on image quality in CBCT performed for evaluating patients before transarterial radioembolization (TARE). We retrospectively included 40 consecutive patients (aged 65 ± 13 years; 23 males) who underwent 45 CBCT examinations (Allura FD 20, XperCT Roll protocol, Philips Healthcare, Best, The Netherlands) in the setting of evaluation for TARE between January 2017 and December 2018. Artifacts caused by coils, catheters, and surgical clips were scored subjectively by four readers on a 5-point scale (1 = artifacts affecting diagnostic information to 5 = no artifacts) using a side-by-side display of uncorrected and MAR-corrected images. In addition, readers scored tumor visibility and vessel discrimination. MAR-corrected images were assigned higher scores, indicating better image quality. The differences between the measurements with and without MAR were most impressive for coils with a mean improvement of 1.6 points (95%CI [1.5 1.8]) on the 5-point likert scale, followed by catheters 1.4 points (95%CI [1.3 1.5]) and clips 0.7 points (95%CI [0.3 1.1]). Improvements for other artifact sources were consistent but relatively small (below 0.25 points on average). Interrater agreement was good to perfect (Kendall's W coefficient = 0.68-0.95) and was higher for MAR-corrected images, indicating that MAR improves diagnostic accuracy. A metal artifact reduction algorithm can improve diagnostic and interventional accuracy of cone beam CT in patients undergoing radioembolization by reducing artifacts caused by diagnostic catheters and coils, lowering interference of metal artifacts with adjacent major structures, and improving tumor visibility.


Asunto(s)
Algoritmos , Artefactos , Tomografía Computarizada de Haz Cónico , Metales , Humanos , Tomografía Computarizada de Haz Cónico/métodos , Femenino , Anciano , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/diagnóstico por imagen , Embolización Terapéutica/métodos , Procesamiento de Imagen Asistido por Computador/métodos
14.
Insights Imaging ; 15(1): 193, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39112682

RESUMEN

OBJECTIVES: Transjugular intrahepatic portosystemic shunt (TIPS) is a catheter-based, minimally invasive procedure to reduce portal hypertension. The aim of the study was to investigate dysfunction and mortality after TIPS and to identify factors associated with these events. METHODS: A retrospective analysis of 834 patients undergoing TIPS implantation in a single center from 1993-2018 was performed. Cumulative incidence curves were estimated, and frailty models were used to assess associations between potentially influential variables and time to dysfunction or death. RESULTS: 1-, 2-, and 5-year mortality rates were 20.9% (confidence interval (CI) 17.7-24.1), 22.5% (CI 19.1-25.8), and 25.0% (CI: 21.1-28.8), 1-year, 2-year, and 5-year dysfunction rates were 28.4% (CI 24.6-32.3), 38.9% (CI 34.5-43.3), and 52.4% (CI 47.2-57.6). The use of covered stents is a protective factor regarding TIPS dysfunction (hazard ratio (HR) 0.47, CI 0.33-0.68) but does not play a major role in survival (HR 0.95, CI 0.58-1.56). Risk factors for mortality are rather TIPS in an emergency setting (HR 2.78, CI 1.19-6.50), a previous TIPS dysfunction (HR 2.43, CI 1.28-4.62), and an increased Freiburg score (HR 1.45, CI 0.93-2.28). CONCLUSION: The use of covered stents is an important protective factor regarding TIPS dysfunction. Whereas previous TIPS dysfunction, emergency TIPS implantation, and an elevated Freiburg score are associated with increased mortality. Awareness of risk factors could contribute to a better selection of patients who may benefit from a TIPS procedure and improve clinical follow-up with regard to early detection of thrombosis/stenosis. CRITICAL RELEVANCE STATEMENT: The use of covered stents reduces the risk of dysfunction after transjugular intrahepatic portosystemic shunt (TIPS). TIPS dysfunction, emergency TIPS placement, and a high Freiburg score are linked to higher mortality rates in TIPS patients. KEY POINTS: The risk of dysfunction is higher for uncovered stents compared to covered stents. Transjugular intrahepatic portosystemic shunt dysfunction increases the risk of instantaneous death after the intervention. A higher Freiburg score increases the rate of death after the intervention. Transjugular intrahepatic portosystemic shunt implantations in emergency settings reduce survival rates.

15.
Diagnostics (Basel) ; 13(20)2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37892098

RESUMEN

Marfan syndrome (MFS) is an autosomal-dominant multisystem connective tissue disorder that is based on mutations in the FBN1 gene and variably affects different organs, including the heart. In this study, we investigated cardiac function with a focus on the left atrium (LA) in a relatively large cohort of patients with MFS. After screening of 1165 patients that had been examined in our center between 2016 and 2020, 231 adult MFS patients with and without aortic operation were included in our study and compared to a healthy control group (n = 106). Cardiac function was assessed by transthoracic echocardiography and NT-proBNP was used as a secretory marker. Most (94.8%) of the patients received genetic testing. Left ventricular function was within normal ranges and not impaired. Interestingly, we found that LA size and secretory activity were increased in MFS patients, despite normal left ventricular filling pressures. This finding was even more pronounced in MFS patients with prior aortic surgery. A correlation between LA size or NT-proBNP levels and the type of pathogenic FBN1 variant could not be identified. Right ventricular function and right atrial size were increased only in MFS patients that had undergone aortic surgery. In conclusion, these findings suggest that MFS leads to structural changes in the LA that are not solely resulting from left ventricular dysfunction, but probably can be considered a primary pathology of MFS.

16.
Curr Oncol ; 30(2): 1502-1515, 2023 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-36826076

RESUMEN

Spectral computed tomography (SCT) allows iodine content (IC) calculation for characterization of hypervascularized neoplasms and thus might help in the staging of neuroendocrine tumors (NETs). This single-center prospective study analyzed the association between SCT-derived IC and tumor response in the follow-up of metastasized NETs. Twenty-six patients with a median age of 70 years (range 51-85) with histologically proven NETs and a total of 78 lesions underwent SCT for staging. Because NETS are rare, no primary NET types were excluded. Lesions and intralesional hotspots were measured in virtual images and iodine maps. Tumor response was classified as progressive or nonprogressive at study endpoint. Generalized estimating equations served to estimate associations between IC and tumor response, additionally stratified by lesion location. Most commonly affected sites were the lymph nodes, liver, pancreas, and bones. Median time between SCT and endpoint was 64 weeks (range 5-260). Despite statistical imprecision in the estimate, patients with higher IC in lymphonodular metastases had lower odds for disease progression (adjusted OR = 0.21, 95% CI: 0.02-2.02). Opposite tendencies were observed in hepatic and pancreatic metastases in unadjusted analyses, which vanished after adjusting for therapy and primary tumor grade.


Asunto(s)
Tumores Neuroendocrinos , Neoplasias Pancreáticas , Humanos , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Tumores Neuroendocrinos/patología , Estudios Prospectivos , Estudios de Seguimiento , Tomografía Computarizada por Rayos X/métodos , Neoplasias Pancreáticas/patología
17.
J Contemp Brachytherapy ; 15(1): 15-26, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36970444

RESUMEN

Purpose: To compare the effectivity and toxicity of monotherapy with computed tomography-guided high-dose-rate brachytherapy (CT-HDRBT) vs. combination therapy of transarterial chemoembolization with irinotecan (irinotecan-TACE) and CT-HDRBT in patients with large unresectable colorectal liver metastases (CRLM) with a diameter of > 3 cm. Material and methods: Forty-four retrospectively matched patients with unresectable CRLM were treated either with mono-CT-HDRBT or with a combination of irinotecan-TACE and CT-HDRBT (n = 22 in each group). Matching parameters included treatment, disease, and baseline characteristics. National Cancer Institute Common Terminology Criteria for Adverse Events (version 5.0) were used to evaluate treatment toxicity and the Society of Interventional Radiology classification was applied to analyze catheter-related adverse events. Statistical analysis involved Cox regression, Kaplan-Meier estimator, log-rank test, receiver operating characteristic curve analysis, Shapiro-Wilk test, Wilcoxon test, paired sample t-test, and McNemar test. P-values < 0.05 were deemed significant. Results: Combination therapy ensued longer median progression-free survival (PFS: 5/2 months, p = 0.002) and significantly lower local (23%/68%, p < 0.001) and intrahepatic (50%/95%, p < 0.001) progress rates compared with mono-CT-HDRBT after a median follow-up time of 10 months. Additionally, tendencies for longer local tumor control (LTC: 17/9 months, p = 0.052) were found in patients undergoing both interventions. After combination therapy, aspartate and alanine aminotransferase toxicity levels increased significantly, while total bilirubin toxicity levels showed significantly higher increases after monotherapy. No catheter-associated major or minor complications were identified in each cohort. Conclusions: Combining irinotecan-TACE with CT-HDRBT can improve LTC rates and PFS compared with mono-CT-HDRBT in patients with unresectable CRLM. The combination of irinotecan-TACE and CT-HDRBT shows satisfying safety profiles.

18.
Magn Reson Med ; 68(2): 600-5, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22213345

RESUMEN

The in vivo pain treatment was successfully performed with the patient in a prone position. The PD-weighted TSE with echo time = 10 ms rendered contrast-to-noise-ratio values of 27 ± 10 for needle/fat, 1.6 ± 5 for needle/muscle, and 4 ± 4.7 for needle/nerve tissue. The mean diameter of the needle artifact was 1.2 ± 0.2 mm. In the T(1)-weighted gradient echo, the needle's artifact diameter was 6 ± 2 mm; the needle's contrast-to-noise ratio relative to muscle tissue was 4 ± 2, 7.6 ± 1.5 for needle/fat, and 5 ± 1 for needle/nerve tissue. With the PD-weighted TSE (echo time = 10 ms) and the T(1)-weighted gradient echo, the needle was imaged reliably throughout the intervention. The butterfly surface coil is feasible for the guidance of spinal interventions in a prone patient.


Asunto(s)
Bupivacaína/administración & dosificación , Dolor de la Región Lumbar/tratamiento farmacológico , Imagen por Resonancia Magnética Intervencional/instrumentación , Imagen por Resonancia Magnética/instrumentación , Magnetismo/instrumentación , Bloqueo Nervioso/instrumentación , Transductores , Anestésicos Locales/administración & dosificación , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Aumento de la Imagen/instrumentación , Inyecciones Espinales/instrumentación , Dolor de la Región Lumbar/diagnóstico , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Resultado del Tratamiento
19.
Ann Transl Med ; 10(5): 240, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35402581

RESUMEN

Background: Aim of this study was to investigate short-term and long-term treatment outcome, complication rates, and patient satisfaction after MRI-guided laser ablation (LA) of osteoid osteoma (OO). Methods: Thirty-five patients with OO in typical and atypical localizations were treated by MRI-guided LA with MRI thermometry in an open 1.0 T system. Twenty-nine patients underwent a standardized telephone interview including questions about recurrence, residual pain or functional symptoms, and satisfaction for short-term follow-up after a mean of 31 months. Twenty-one of these patients were available for long-term telephone follow-up after a mean of 116 months. Results: Technical success of MRI-guided LA was 100% without major complications. Two minor complications included transient local inflammation and transient damage of the peroneal nerve associated with improper patient positioning during the procedure. Primary clinical success was 92% (11/12) in typically located OO and 82% (14/17) in atypically located OO. Secondary clinical success after repeat ablation was 100% regardless of OO location. Patient satisfaction and acceptance of the intervention were very good at both short-term (97%) and long-term (100%) follow-up. Conclusions: MRI-guided LA of OO is a safe and effective treatment option resulting in high short-term and long-term patient satisfaction and acceptance rates. Recurrence and adverse events were more common in patients with atypically located OO. Level of Evidence: Level 3, non-randomized follow-up study.

20.
Insights Imaging ; 13(1): 73, 2022 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-35416547

RESUMEN

BACKGROUND: TIPS is an established treatment for portal hypertension. The aim was to analyze how patient selection for TIPS implantation and procedural aspects have changed over 25 years. Routinely collected demographic, clinical, laboratory, and procedural data of 835 patients treated with TIPS in a single center were used. Time trends over the observational period from 1993 to 2018 were retrospectively analyzed. Descriptive statistical analysis was performed. RESULTS: The most common indication for TIPS implantation has changed significantly from secondary prevention of variceal hemorrhage in the early years to treatment of recurrent ascites. During the observation period, increasingly more severely ill patients became TIPS candidates. There was little change in MELD scores over this period (in total median 13.00; IQR 10.00-18.00). The proportion of patients with Child-Pugh C cirrhosis increased. The most frequent underlying diseases in total were alcohol-related liver disease (66.5%) and viral hepatitis (11.9%). However, shares of cryptogenic liver cirrhosis, autoimmune hepatitis, and NASH increased over time. The proportion of patients post liver transplant also increased. While bare metal stents were standard in the past, use of covered stents increased. The success rate of TIPS (defined by successful implantation and a decrease in the portosystemic pressure gradient ≤ 12 mmHg) increased significantly over time. The total success rate according to this definition was 84.9%. CONCLUSION: The results of our analysis reflect technical developments in TIPS, especially in terms of stent material and gains in clinical experience, particularly regarding indications and patient selection for TIPS implantation.

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