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1 Purpose of the Study:
The purpose of this retrospective study was to assess the volumetric changes of our institutional pediatric neuroblastoma in response to various therapeutic protocols.
2 Materials and Methods:
A retrospective study was conducted on children with neuroblastoma from different anatomical locations including suprarenal, paraspinal, pelvic, mediastinal and cervical neuroblastoma primaries. These children underwent tumor-stage based therapeutic protocols in Johann Wolfgang Goethe University Hospital, Frankfurt am Main, Germany, between January 1996 and July 2008. The study included 72 patients (44 males and 28 females). Patient demographics (age and gender), disease-related symptoms, laboratory results (tumor biomarkers including ferritin, neuron specific enolase, and urine catecholamine) and histopathological reports were collected from the electronic medical archiving system and subsequently analyzed.
Patients were classified into following groups according the anatomical origin of the primary neuroblastoma into:
1) Suprarenal neuroblastoma Group: This group included patients with neuroblastoma arising from the suprarenal gland. This group composed of 54 patients with male to female ratio (32:22).
2) Paravertebral neuroblastoma Group: This group composed of 6 male patients.
3) Mediastinal neuroblastoma Group: This group included patients with mediastinal neuroblastoma and composed of 3 patients (1 male and 2 females).
4) Pelvic neuroblastoma Group: This group included patients with pelvic neuroblastoma and composed of 6 patients (3 males and 3 females).
5) Cervical neuroblastoma Group: This group included patients with cervical neuroblastoma and composed of 2 male patients.
3 Results:
The mean volume of all suprarenal neuroblastoma group involved in the study before therapy was 176.62 cm3 (SD: 234.15) range: 239.4-968.9cm3. The mean initial volume of all suprarenal neuroblastoma group who underwent observation protocol was 86.0378 cm3 (SD: 114.44) range: 5.2-347.94cm3. Volumetric evaluation of suprarenal neuroblastoma following observation (Wait and See) protocol revealed continuous reduction of the tumor volumes in a statistically significant manner during the follow up periods up to 12 months with p value of less than 0.05. The volumetric changes afterwards were statistically insignificant.
The mean initial volume of all suprarenal neuroblastoma group who underwent primary surgery protocol was 42.4 cm3 (SD: 28.5) range: 7.5-90cm3. Complete surgical resection of the tumor was not feasible in all lesions due to local tumor extension and / or infiltration with the associated risk of injury of nearby organs or structures. However statistical analysis of the volumetric changes in the successive follow up periods did not reveal statistical significance.
Volumetric estimation of the tumor in the subsequent follow up periods revealed significant changes within the period first (3-9 month periods). The changes afterwards were statistically non significant. On the other hand, the mean initial volume of all suprarenal neuroblastoma group who underwent combined chemotherapy and Stem cell transplantation protocol only without surgical interference was 99.98cm3 (SD:46.2) range: 48.48-160.48 cm3. In this group the volumetric changes were variable and difference in volumes in follow up was statistically non significant during the follow up period.
The mean initial volume of all abdominal paravertebral neuroblastoma group was 249.197cm3 (SD: 249.63) range: 9.6-934cm3. The mean initial volume of all pelvic neuroblastoma group was 118.88cm3 (SD: 50.61) range: 73.4-173.4cm3. The mean initial volume of all mediastinal neuroblastoma group was 189.7cm3 (SD: 139.057) range: 10.7-415 cm3. The mean initial volume of all cervical neuroblastoma group was 189.7cm3 (SD: 139.057) range: 10.7-415 cm3. The volumetric measurements in the corresponding follow up periods according to the therapeutic protocol of abdominal paravertebral neuroblastoma, pelvic neuroblastoma, mediastinal and cervical neuroblastoma revealed significant change in the tumor volume within the early 3-6 months from the initial therapy while subsequently the tumor volumetric changes were statistically non significant.
4 Conclusion:
In conclusion, the role of MRI volumetry in the evaluation of tumor response is dependent on the risk adapted concept of neuroblastoma with the combination of different imaging modalities as well the therapeutic protocol. MRI Volumetry in addition to new protocols such as Whole-body imaging and 3D visualization techniques are gaining more importance and acceptance.
Purpose of the Study: The purpose of the current study was to evaluate the role of radiofrequency (RF) and microwave (MW) ablation in the treatment of pulmonary neoplasms. Materials and Methods: From March 2004 to January 2009, 164 patients (92 males, 72 females; mean age 59.7 years, SD: 10.2) underwent computed tomography (CT)-guided percutaneous RFA of pulmonary malignancies. RFA was performed on 248 lung lesions (20 primary lesions and 228 metastatic lesions) in 248 sessions (one lesion per session). Tumors were pathologically proven and were classified as primary lung neoplasms in 20 patients (non-small cell lung cancer) and as metastatic lung neoplasms in 144 patients. RFA was performed using: a) CelonProSurge bipolar internally cooled applicator b) RITA®StarburstTMXL. From December 2007 to October 2009, 80 patients (30 males, 50 females; mean age 59.7 years, range: 48-68, SD: 6.4) underwent computed tomography (CT) guided percutaneous MW ablation of pulmonary metastases from variable histopathological primaries. MW was performed on 130 lung lesions in 130 sessions (one lesion per session) using Valleylab TM system. Results: The overall success rate of RFA was 67.7% (168/248 lesions), with overall failure rate either due to tumor residue or recurrence on follow up in 32.3% (80/248) with mean time to tumor progress was 5.6 months SD: 2.99 (Range:1-18 months). Complete successful ablation was achieved in patients treated by MWA in 73.1% (95/130 lesions), with failure rate either due to tumor residue or recurrence on follow up in 26.9% (35/130) with mean time to tumor progress 6 months SD: 2.83 (Range:1-12months). Correlation of the histopathological type of the lesion and the end result of ablation therapy revealed insignificant correlation in both RFA and MWA (p > 0.1). The preablation tumor size was one of the most significant factors that determined the end result of ablation. In RFA successful tumor ablation was significant statistically for lesions with maximal axial diameter up to 2.5 cm (110/140) in comparison to lesions of more than 2.5 cm in maximal axial diameter (58/108) (Fisher’s exact test: p < 0.0001). While in MW ablated lesions successful tumor ablation was significant statistically for lesions with maximal axial diameter up to 3 cm (90/110) in comparison to lesions of more than 3 cm in maximal axial diameter (5/20) (Fisher’s exact test: p < 0.001). The location of the lesion was another important factor that determined the end result of ablation. In both RFA and MWA successful ablation was significantly more correlated to peripheral lesions (RFA: 120/160, 80% / MWA: 80/100, 80%) than centrally located lesions (RFA: 48/88, 50%; MWA: 15/30, 50%) (Fisher’s Exact Test: p > 0.001). For successfully RFA ablated cases mean preablation tumor volumes 1.9 cc SD: 0.9 (range: 0.3 - 4.25 cc) while for failed cases the mean tumor volume was 3.7 SD: 2.4 (range: 0.8 – 6.8cc). For successfully MW ablated cases the mean preablation tumor volume: 2.4 cc SD: 2.2 (range: 0.25-8.2 cc) while for failed cases the mean tumor volume was 3.5 SD: 2.6 (range: 0.3 – 7.1 cc). In RFA the survival rates at 12, 24 and 36 months were 90%, 78% and 68% respectively while in MWA treated patients the survival rate within 12 months follow up period was 96% while at 20 month the survival rate was 77%. Complications associated with the ablation therapy were: a) procedure related mortality: 0.4% (1/248) in RFA due to massive pulmonary hemorrhage versus 0% (0/130) in MWA, b) pneumothorax: 11.3% (28/240) in RFA versus 8.5% (11/130) in MWA, c) pulmonary Hemorrhage: 17.7% (44 of 248 sessions) of which one patient had massive uncontrolled bleeding and immediate death versus 6.2% (8/130) in MWA, d) pleural effusion: 3.2 % (8 of 248 sessions) in RFA versus 3.8 % (6/130) in MWA, e) hemoptysis: 4% (10/248) in RFA versus 4.6% (6/130) in MWA ranging from mild tinged sputum to frank bleeding, f) infection: 0.4% (1/248) in RFA, versus 0% in MWA, and g) post ablation pain: 10% (25/248) in RFA versus 9.2% (12/130) in MWA. Pain was generally adequately controlled by analgesics. Conclusion: Radiofrequency and microwave ablation are effective minimally invasive tools and may be safely applied for management of lung malignancy. The success of ablation therapy is significantly correlated to the preablation tumor size, volume and tumor location.
2.1. Background & purpose The recent introduction of new technical innovations such as CT perfusion (CTP) and dual energy CT (DECT) increases the diagnostic abilities of CT for imaging of the head and neck (H&N). The aim of this work was to evaluate the role of CTP and DECT in head and neck imaging. The first part tests whether CTP can differentiate between malignant H&N tumors and surrounding muscle, and discusses the impact of arterial input selection and tumor region of interest (ROI) on CTP of H&N cancer. The second part of the study evaluates radiation dose and image quality of DECT of the H&N. Finally the use of DE derived weighted averaging to improve lesion delineation and image quality is discussed. 2.2. Patients and methods CT perfusion Retrospective analysis of CTP was done for a total number of 55 cases of H&N tumors. Perfusion parameters were calculated for 33 cases of squamous cell carcinoma (SCC) and compared to those of muscles. CTP parameters of 50 cases of H&N tumors calculated using different arterial input functions were compared. CTP was calculated for 28 SCC cases using the single dynamic CT section that shows maximal tumor dimension compared to using average values obtained from all tumor-containing dynamic CT sections. Dual energy CT of head and neck This prospective part of the study was further divided into 2 parts. In the first part 32 consecutive patients underwent DECT of the H&N and were compared to a standard single energy CT (SE) control group. Radiation doses were compared. Weighted-average images from raw data of the 2 DE tubes (weighting factor 0.3 from 80 kVp and 0.7 from 140 KVp) were compared to SE images. Image noise was compared at 5 anatomic levels. Two blinded readers compared subjective overall image quality on a 5-point grading scale. In the second part 35 proved SCC cases underwent DECT of the neck. Pure 140 kVp and 80 kVp image datasets as well as weighted-average images from raw data of the 2 DE tubes at weighting factors 0.3, 0.6, 0.8 (30%, 60% and 80% from 80 kVp raw data respectively) were reconstructed. Objective image noise, contrast to noise ratio (CNR) and subjective image quality were compared between the 5 image datasets. Results CT perfusion Tumor perfusion parameters were significantly higher than those of muscle (p <0.05). Significant high correlation with no significant differences between the means (p >0.05) were observed between perfusion parameters obtained using internal carotid artery (ICA) versus external carotid artery (ECA) and ipsilateral versus contralateral ICA. High correlation was observed between perfusion parameters calculated using one section with maximal tumor dimension and the average of multiple sections. Differences between the means were non significant, p values>0.05. The 95% limits of agreement between repeated measurements using average of multiple sections were slightly narrower for blood volume and permeability than those of repeated measurements using one section. Dual energy CT of head and neck CTDIvol was 12% lower with DE than SECT (p<0.0001). There were no significant differences in objective noise between DECT and SECT at any of the anatomic levels (p >0.05). There were no significant differences between DE- and SECT in attenuation measurements, all p values >0.05. No significant differences in subjective image quality scores were observed between DE- and SECT at any of the 5 anatomic levels (p >0.05). At weighting factor 0.6 the lesion CNR was significantly higher than at weighting factor 0.3 and at pure 140 kVp image dataset (p< 0.0001); while non significantly lower than at weighting factor 0.8 and pure 80 kVp (p=1.00). The 0.6 weighting factor was rated the best at subjective image quality and lesion delineation. 2.4. Conclusion In conclusion; this study demonstrated the ability of CTP to differentiate SCC from surrounding muscle tissue. The choice of arterial input selection has no significant impact on quantitative CTP of H&N tumors. CTP of SCC calculated from one section with maximal tumor dimensions and the average values from multiple sections are not significantly different. The second part of the study showed that DE scanning can be routinely used for H&N imaging; preserving high diagnostic image quality even when the radiation dose was lowered by 12%. Average weighting of DE raw data, with a weighting factor 0.6, results in significant improvement in both tumor delineation and image quality.
Aim: To study the changes in leiomyoma volume following uterine artery embolization (UAE) and to correlate these changes with the initial leiomyoma volume and location within the uterus and to evaluate the impact of preprocedural prediction of the best tube angle obliquity for visualization of the uterine artery origin using 3D-reconstructed contrast-enhanced MR angiography (CE-MRA) on the radiation dose, fluoroscopy time and contrast medium volume used during UAE. Materials and Methods: The study was performed in two parts. The first part was retrospectively done on 28 patients (age range: 37-57 years, mean: 48 years, SD: 4.81) in whom UAE was performed. All leiomyomas in all patients were evaluated. In total, 84 leiomyomas were evaluated. MRI studies were performed before, 3 months and 1 year after UAE. The volumes and location of each leiomyoma in each patient were evaluated in consensus by two radiologists. The second part included 40 consecutive patients (age range: 37-56 years, mean: 46 years, SD: 4.49) and was done in a controlled prospective/retrospective manner. In 20 sample patients (prospective part) pre-procedural prediction of the best tube angle obliquity was predicted using 3D-reconstructed CE-MRA and provided to the interventionalist. 3D-reconstruction was done using Inspace application. The radiation dose, fluoroscopy time and contrast medium volume for those patients were compared with the data of the last 20 procedures (control) performed by the same interventionalist (retrospective part). Results: For the first part the mean pre-embolization volume was 51.6 cm3 range:0.72-371.1cm3, SD=79.3). At 3-month follow-up 83 (98.8%) leiomyomas showed a mean volume reduction of 52.62% (range: 12.79–96.67%, SD=21.85) and 1 leiomyoma (1.2%) increased in volume. At 1-year follow-up 5 (6%) leiomyomas were not detectable, 72 (85.7%) showed a further mean of 20.5% (range: 2.52–58.72%, SD=11.92) volume reduction compared to the 3-month follow-up volume and 7 (8.3%) leiomyomas increased in volume. A statistically significant (p=0.026 at 3-month, p=0.0046 at 1-year) difference in percentage of volume change was observed based on leiomyoma location; submucous leiomyomas showed the largest volume reduction. The initial leiomyoma volume showed a weak negative correlation (Spearman's correlation-coefficient =-0.35 at 3m and -0.36 at 1y) with the leiomyoma volume change. For the second part the tube angle prediction resulted in a significant reduction of the radiation dose utilized (p<0.001), fluoroscopy time (p=0.002) and contrast medium volume (p<0.001) for the sample patients when compared with the control patients. The overall radiation dose was reduced from a mean of 11044 μGym2 to a mean of 4172.5 μGym2, fluoroscopy time was reduced from a mean of 15.45 minutes to 8.81 minutes and contrast medium volume was reduced from a mean of 135 ml to 75 ml. Conclusion: UAE results in significant leiomyoma volume reduction at 3-month and 1- year follow-up. The leiomyoma location plays an important role in volume changes while the initial leiomyoma volume plays a minor role. Pre-procedural prediction of the best tube angle obliquity for visualization of the origin of the uterine artery using 3D-reconstructed CE-MRA results in a significant reduction of the radiation dose, fluoroscopy time and contrast medium volume used during UAE.
Purpose: The aim of this work was to retrospectively identify prognostic factors for patients with neuroendocrine liver metastases (NELM) undergoing conventional transarterial chemoembolization (c-TACE), microwave ablation (MWA) or laser interstitial thermal therapy (LITT) and to determine the most effective therapy in terms of volume reduction and survival.
Method: Between 1996 and 2020, 130 patients (82 men, 48 women) were treated with c-TACE, 41 patients were additionally treated with thermoablative procedures.
Survival was retrospectively analyzed by using Kaplan-Meier-method. Prognostic factors were derived by using cox-regression. To find predictive factors for volume reduction due to c-TACE, a mixed-effects model was used.
Results: With c-TACE, an overall median volume reduction of 23.5 % was achieved. An average decrease of tumor volume was shown until the 6th c-TACE treatment, then the effect stopped. So, the median volume reduction off all lesions takes on a negative value from the 7th c-TACE intervention onwards. The mixed-effects model demonstrated that c-TACE interventions were most effective at the beginning of c-TACE therapy, and that treatment breaks longer than 90 days negatively influenced the outcome. For all patients evaluable for survival, Kaplan-Meier analysis showed a 1-year survival rate of 75 % and a 5-year survival rate of 36 %. Significant prognostic factors for survival were number of liver lesions (p = 0.0001) and therapeutical intention (p < 0.0001). Considering the clinical indication, 90.9 % of curative patients and 43.6 % of palliative patients responded to c-TACE therapy and thus could be submitted to a thermoablative procedure. Minor and one major complication occurred in 20.3 % of LITT and only in 8.6 % of MWA interventions. Complete ablation was observed in 95.7 % (LITT) and 93.1 % (MWA) of interventions
Conclusions: C-TACE is an effective treatment for volume reduction of NELM, however efficacy decreases after the 6th intervention and treatment breaks longer than 90 days should be avoided. With thermal ablation, a high rate of complete ablation was achieved and survival improved. Significant factors for survival were found and may be used as prognostic factors in the future.
Background: In the Computer Tomography imaging, examinations for the diagnosis of lesions of the upper abdomen currently use water-soluble, iodinated, non-ionic contrast agents with low molecular weight. One possibility to reduce the time of the examination and X-ray exposure is to increase the injection rate. However, higher injections rates lead to increased hypersensitivity reactions and extravasation rates. Furthermore, cardiac pump function does not always allow for the transportation of such a large volume within one heartbeat. With a contrast agent of higher iodine concentration, the injection rate may be reduced without decreasing the iodine delivery rate while reducing the volume load of the heart.
Aim: to compare the performance and image quality of two injection protocols of contrast medium for multiphasic CT imaging of malignant hepatic lesions; one using Imeron 300 at an injection rate of 5 ml/ sec and the second using Imeron 400 at an injection rate of 3,7 ml/ sec, for multiphasic CT imaging of malignant hepatic lesions, in order to optimise the iodine concentration and injection rate of the contrast agent Imeron in the Multislice Spiral-CT of the upper abdomen.
Materials and methods: the current prospective, single centre, double-blinded, randomised and interindividual comparison study included 50 patients (29 males and 21 females) with a mean age of 63,3 years. Patients were randomised to one of the two injection protocols. Image evaluation included qualitative assessment (technical quality, presence of artefacts and overall contrast quality) and quantitative assessment (measuring the difference in HU between the lesion and the surrounding hepatic tissue). The difference between both protocols was tested for statistical significance using the Wilcoxon-Mann-Whitney test and the Two-Sample t-test.
Results: there was no statistically significant difference between both protocols regarding the technical quality of images, both in the AP (p = 0,46) and in the venous phase (p = 0,48). Additionally, no statistically significant difference was found regarding the presence of artefacts related to the contrast medium, both in the AP (p = 0,46) and in the venous phase (p = 0,46), as well as regarding the overall contrast quality of images both in the AP (p = 0,50) and in the venous phase (p = 0,48). Quantitative assessment showed no statistically significant difference regarding the difference in HU measurement between the hepatic lesion and the surrounding hepatic tissue, both in the AP (p = 0,36) and in the venous phase (p = 0,92).
Conclusion: in the multiphasic CT imaging of the liver, reducing the injection rate of the contrast medium Imeron from 5 ml/ sec to 3,7 ml/ sec while increasing the iodine strength of the agent from 300 to 400 mg/ml, respectively, and thus keeping the iodine injection flow rate constant, produces similar signal intensities and results in similar technical, image and overall contrast qualities..
Keywords: Contrast-medium, injection rate, iodine concentration, hepatic malignancy, multiphasic CT