Real-time MR-guided brain biopsy using 1.0-T open MRI scanner.

OBJECTIVES: To evaluate the safety, feasibility and diagnostic performance of real-time MR-guided brain biopsy using a 1.0-T open MRI scanner. METHODS: Medical records of 86 consecutive participants who underwent brain biopsy under the guidance of a 1.0-T open MRI scanner with real-time and MR fluoroscopy techniques were evaluated retrospectively. All procedures were performed under local anaesthesia and intravenous conscious sedation. Diagnostic yield, diagnostic accuracy, complication rate and procedure duration were assessed. The lesions were divided into two groups according to maximum diameters: ≤ 1.5 cm (n = 16) and > 1.5 cm (n = 70). The two groups were compared using Fisher's exact test. RESULTS: Diagnostic yield and diagnostic accuracy were 95.3% and 94.2%, respectively. The diagnostic yield of lesions ≤ 1.5 cm and > 1.5 cm were 93.8% and 95.7%, respectively. There was no significant difference in diagnostic yield between the two groups (p > 0.05). Mean procedure duration was 41 ± 5 min (range 33-49 min). All biopsy needles were placed with one pass. Complication rate was 3.5% (3/86). Minor complications included three cases of a small amount of haemorrhage. No serious complications were observed. CONCLUSIONS: Real-time MR-guided brain biopsy using a 1.0-T open MRI scanner is a safe, feasible and accurate diagnostic technique for pathological diagnosis of brain lesions. The procedure duration is shortened and biopsy work flow is simplified. It could be considered as an alternative for brain biopsy. KEY POINTS: • Real-time MRI-guided brain biopsy using a 1.0-T open MRI scanner is safe, feasible and accurate. • No serious complications occurred in real-time MRI-guided brain biopsy. • Procedure duration is shortened and biopsy work flow is simplified.

1.0T MR-guided percutaneous coaxial cutting needle biopsy in pancreatic lesion diagnosis.

BACKGROUND: Pancreatic carcinoma is a common cause of cancer deaths worldwide. Biopsy is often required for the initial diagnosis of pancreatic masses. Biopsy can be performed endoscopically or percutaneously with computed tomography (CT) and ultrasound (US) guidance. MRI offers many inherent advantages over CT and US. PURPOSE/HYPOTHESIS: To prospectively evaluate the feasibility, accuracy, and safety of MRI-guided percutaneous coaxial cutting needle biopsy of pancreatic lesions using an open 1.0T high-field MR scanner. STUDY TYPE: Prospective. POPULATION: Thirty-one patients with 31 pancreatic lesions underwent MR-guided percutaneous coaxial cutting needle biopsy. FIELD STRENGTH/SEQUENCE: 1.0T T2 WI-TSE PDW-aTSE T1 WI-TFE. ASSESSMENT: Final diagnosis was confirmed by surgery and clinical follow-up for at least 12 months. The accuracy, sensitivity, and specificity were calculated. Complications were recorded. STATISTICAL TESTS: There was no statistical analysis in this study. RESULTS: The procedure was technically successful and final biopsy samples were adequate for histopathological examination in all patients. Biopsy pathology revealed malignant pancreatic tumor in 25 patients (25/31, 80.6%), and benign pancreatic lesions were present in six patients (6/31, 19.4%). The final diagnosis was pancreatic malignancy in 27 patients and benign disease in four patients, which was confirmed by surgery and clinical follow-up. Two biopsy results were false-negative. The diagnostic accuracy in biopsies was 93.5% (29 of 31). The sensitivity to detect a malignant disease was 92.6% (25 of 27), and the specificity was 100%. All patients tolerated the procedure well; minor peripancreatic hemorrhage was found in two patients after the procedure, and none had major complications either during or after the procedure. DATA CONCLUSION: MRI-guided percutaneous biopsy of pancreatic lesions using an open 1.0T high-field scanner has high diagnostic accuracy, which is feasible and safe for use in clinical practice. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2018;48:382-388.

MR-guided percutaneous biopsy of solitary pulmonary lesions using a 1.0-T open high-field MRI scanner with respiratory gating.

OBJECTIVES: To prospectively evaluate the feasibility, safety and accuracy of MR-guided percutaneous biopsy of solitary pulmonary lesions using a 1.0-T open MR scanner with respiratory gating. METHODS: Sixty-five patients with 65 solitary pulmonary lesions underwent MR-guided percutaneous coaxial cutting needle biopsy using a 1.0-T open MR scanner with respiratory gating. Lesions were divided into two groups according to maximum lesion diameters: ≤2.0 cm (n = 31) and >2.0 cm (n = 34). The final diagnosis was established in surgery and subsequent histology. Diagnostic accuracy, sensitivity and specificity were compared between the groups using Fisher's exact test. RESULTS: Accuracy, sensitivity and specificity of MRI-guided percutaneous pulmonary biopsy in diagnosing malignancy were 96.9 %, 96.4 % and 100 %, respectively. Accuracy, sensitivity and specificity were 96.8 %, 96.3 % and 100 % for lesions 2.0 cm or smaller and 97.1 %, 96.4 % and 100 %, respectively, for lesions larger than 2.0 cm. There was no significant difference between the two groups (P > 0.05). Biopsy-induced complications encountered were pneumothorax in 12.3 % (8/65) and haemoptysis in 4.6 % (3/65). There were no serious complications. CONCLUSIONS: MRI-guided percutaneous biopsy using a 1.0-T open MR scanner with respiratory gating is an accurate and safe diagnostic technique in evaluation of pulmonary lesions. KEY POINTS: • MRI-guided percutaneous lung biopsy using a 1.0-T open MR scanner is feasibility. • 96.9 % differentiation accuracy of malignant and benign lung lesions is possible. • No serious complications occurred in MRI-guided lung biopsy.

MRI-guided percutaneous transpedicular biopsy of thoracic and lumbar spine using a 0.23t scanner with optical instrument tracking.

PURPOSE: To prospectively evaluate the safety and accuracy of magnetic resonance imaging (MRI)-guided percutaneous transpedicular biopsy of thoracic and lumbar spine using 0.23T magnetic resonance imaging with optical tracking. MATERIALS AND METHODS: Sixty-seven thoracic and lumbar spine lesions in 67 patients underwent MRI-guided percutaneous transpedicular biopsy using 0.23T MRI with optical tracking. These lesions were divided into two groups according to the location: 16 lesions in the thoracic spine and 51 lesions in the lumbar spine. The diagnostic accuracy, sensitivity, and specificity were calculated, and comparison of the two groups was performed using Fisher's exact test. Each patient was monitored for complications. RESULTS: All specimens obtained were sufficient for diagnosis. Histological examination of MRI-guided percutaneous biopsy revealed 38 malignant and 29 benign lesions. The final diagnoses from surgery or clinical follow-up were 42 malignant lesions and 25 benign lesions. The combined diagnostic performance of MRI-guided percutaneous transpedicular thoracic and lumbar biopsy in diagnosing malignant tumors was as follows: accuracy, 94%; sensitivity, 89%; and specificity, 100%. There was no significant difference between the two groups (P = 1, Fisher's exact test). No serious complications occurred. CONCLUSION: MRI-guided percutaneous transpedicular biopsy is a safe and accurate diagnostic technique to evaluate thoracic and lumbar spine lesions.

Dosimetric evaluation of iodine-125 brachytherapy for brain tumors using MR guidance combined with a three-dimensional non co-planar template.

PURPOSE: To investigate the consistency between preoperative and postoperative dosimetry when 125I brachytherapy for brain tumors is performed with magnetic resonance (MR) guidance and a three-dimensional non co-planar template (3DNPT). METHODS AND MATERIALS: Thirty patients with brain tumors (metastatic or gliomas) underwent radioactive 125I seed implantation. A preoperative treatment plan was determined with MR imaging, and the operation was done under 3DNPT assistance and MR guidance. The dosimetry was verified postoperatively based on postoperative CT-MR fusion images. Postoperative dosimetric parameters and implant quality indices were defined and compared with those in the preoperative treatment plan. Furthermore, a comparison of preoperative and postoperative doses to normal brain tissues and organs at risk was also performed. RESULTS: All mean postoperative dosimetries were calculated. Target coverage parameters D90, D100, %CTV100, %CTV150, and %CTV200 were 143.6 cGy, 76.6 cGy, 88.2%, 63.1%, and 41.4%, respectively. The values of implant quality indices CI, EI, and HI were 0.75, 0.14, and 0.28, respectively. No significant differences between most preoperative and postoperative dosimetric parameters were found (p > 0.05). The differences were also insignificant for organs at risk. Postoperative %CTV150 and %CTV200 were higher than the preoperative, whereas postoperative HI was significantly lower than in the treatment plan. CONCLUSIONS: Magnetic resonance guidance combined with 3DNPT allows accurate positioning and direction in 125I brachytherapy for brain tumors. However, seed distribution and dose homogeneity require further improvement.

Three-dimensional template combined with MR-guided iodine-125 brachytherapy for recurrent brain metastases.

Purpose: Treatment of recurrent brain metastases is extremely challenging. Here, we evaluated the feasibility and efficacy of an individualized three-dimensional template combined with MR-guided iodine-125 (125I) brachytherapy in the treatment of recurrent brain metastases. Material and methods: Twenty-eight patients with recurrent 38 brain metastases underwent 125I brachytherapy from December, 2017 to January, 2021. A pre-treatment brachytherapy plan and three-dimensional template were generated according to isovoxel T1-weighted MR images. 125I seeds were implanted under the guidance of three-dimensional template and 1.0-T open MR imaging. Dosimetry verification was performed based on CT/MR fusion images. Pre-operative and post-operative dosimetry parameters of D90, V100, and conformity index (CI) were compared. Overall response rate (ORR), disease control rate (DCR) at 6 months, and 1-year survival rate were calculated. Median overall survival (OS) measured from the date of 125I brachytherapy was estimated using Kaplan-Meier method. Results: No significant differences were observed between pre-operative and post-operative D90, V100, and CI values (p > 0.05). The ORR and DCR at 6 months were 91.3% and 95.7%, respectively. The 1-year survival rate was 57.1%. The median OS was 14.1 months. Two cases of minor hemorrhage and 5 cases of symptomatic brain edema were observed during the study. All clinical symptoms were alleviated after corticosteroid treatment applied for 7 to 14 days. Conclusions: A three-dimensional template combined with MR-guided 125I brachytherapy in the treatment of recurrent brain metastases is feasible, safe, and effective. This novel 125I brachytherapy strategy is an attractive alternative in the treatment of brain metastases.

A Comparative Study of Antitumor Immunity Induced by Radiofrequency Microwave and Cryoablation in Hepatocellular Carcinoma.

PURPOSE: This study aimed to compare the immune responses induced by microwave ablation (MWA), radiofrequency ablation (RFA), and cryoablation (CRYO) in hepatocellular carcinoma (HCC) and identify differences in immune responses and the timing of immune changes. MATERIALS AND METHODS: A bilateral subcutaneous model was established in C57 mice, and the successfully modeled mice were divided into the microwave (n = 15), radiofrequency (n = 15), CRYO (n = 15), control (n = 9), and blank groups (n = 3). Mice in the control group were dissected before ablation, whereas mice in the three ablation groups underwent ultrasound-guided ablation of one axillary tumor. Three mice were sacrificed and dissected at 1-4 weeks after ablation. After tissue processing, flow cytometry was used to detect the levels of CD8 + T and regulatory T (Treg) cells in the tissue, and western blotting was used to assess the level of programmed cell death ligand 1 (PD-L1) protein in the tumor tissue. RESULTS: The pattern of immune changes after the three types of ablation was consistent, with immune changes occurring at 3-4 weeks. CRYO induced the most significant increase in the percentage of CD8 + T cells. There were no significant differences in the levels of Treg cells and the level of PD-L1 protein among the three types of ablation (p > 0.05), but the decline in Treg cells and PD-L1 protein level caused by CRYO was the most pronounced. CONCLUSION: In the HCC mouse model, the immune changes following the three types of ablation were consistent, with immune changes occurring at 3-4 weeks. Among them, CRYO elicited the strongest adaptive immune response, and RFA outperformed MWA.

Magnetic resonance-guided repeat biopsy of suspicious malignant lung lesions after an initial negative computed tomography-guided Biopsy.

Objective: This study sought to establish the diagnostic utility of performing a second biopsy using an magnetic resonance (MR)-guided percutaneous transthoracic needle biopsy (PTNB) approach in patients with suspicious malignant lung lesions that had already undergone an initial negative computed tomography (CT)-guided biopsy. Materials and Methods: This study evaluated 31 patients with suspicious lung lesions (18 males, 13 females; mean age: 62.1 ± 11.3 years) that had previously undergone CT-guided PTNB with negative pathological findings January 2015-November 2020. A final histopathological diagnosis was made based on resected lung lesion specimens or, when resection was not conducted, on clinical diagnosis following a ≥6-month follow-up. The diagnostic accuracy of MR-guided secondary lung biopsy was determined by comparing the lung biopsy results for each patient to their final diagnosis. Results: 1.0T open MR-guided secondary lung biopsy was performed for 31 lesions (20 central, 11 peripheral; mean size, 5.3 ± 2.0 cm). The pathological results revealed 20/31 (64.5%) lesions to be malignant (14 adenocarcinoma, 4 squamous cell carcinoma, and 2 small-cell lung cancer) as detected by 1.0T open MR-guided PTNB and confirmed by surgical pathology and clinical follow-up. There were three instances of biopsy-induced complications including hemorrhage in 6.5% of the patients (2/31) and pneumothorax in 3.2% of the patients (1/31). No patients experienced severe complications. Conclusion: For individuals with clinically suspicious lung lesions that initially received negative CT-guided PTNB findings, 1.0T open MR-guided secondary lung biopsy is a safe and effective secondary diagnostic approach.

Multiparametric magnetic resonance-guided and monitored microwave ablation in liver cancer.

PURPOSE: The objective of our study was to prospectively evaluate the feasibility, effectiveness, and safety of 1.0T open multiparametric magnetic resonance (MR)-guided and monitored microwave ablation (MWA) of liver cancer. MATERIALS AND METHODS: Fifty-six liver lesions (12 - initial hepatocellular carcinoma, 34 - recurrent hepatocellular carcinoma, and 10 - metastatic liver cancers) in 45 patients were treated with MWA ablation using MR guidance and monitoring. The mean diameter of the liver lesions was 1.7 ± 0.9 cm (range, 0.5-4.6 cm). The 56 liver lesions were divided into 3 groups according to diameter: the <1.0 cm group (17 lesions), the 1.0-2.0 cm group (19 lesions), and the >2.0 cm group (20 lesions). Technical success, technical effectiveness, local tumor progression, procedure duration, and complications were assessed. Primary technical effectiveness was assessed 3 months after the MWA, while local tumor progression was assessed more than 3 months after the MWA. The follow-up time for assessment of treatment response ranged from 12 to 30 months (median, 23 months). RESULTS: The technical success rate was 100%. Primary technical effectiveness was achieved in 52/56 (92.8%) lesions. Local tumor progression was detected in three tumors after initial technical effectiveness. The median duration of the intervention per tumor was 66 min (range, 40-156 min). There were no significant differences between lesion groups in the technical success rate, primary technical effectiveness rate, or local tumor progression rate. There were no major complications following the ablation therapy. CONCLUSIONS: 1.0T open multiparametric MR-guided and MR-monitored MWA for liver cancer is safe and feasible and decreases the risk of local tumor progression; it also provides good primary technique effectiveness rates and is especially suitable when ultrasound and CT facilitated treatments are inappropriate.

Magnetic resonance-guided ablation of liver tumors: A systematic review and pooled analysis.

PURPOSE: The purpose of this study is to study the clinical outcomes of different types of magnetic resonance (MR)-guided ablation for the treatment of liver tumors by performing a systematic review and pooled analysis. MATERIALS AND METHODS: A comprehensive literature search was performed for clinical trials published from January 1997 to October 2019 in PubMed, the Web of Science, Embase, and the Cochrane Library. Pooled analyses were performed to obtain the complete ablation (CA), complication, progression-free survival (PFS), and overall survival (OS) rates. RESULTS: Thirty studies were eligible, including four studies on MR-guided microwave ablation (MWA); 14 studies on MR-guided radiofrequency ablation (RFA); one study on both MR-guided MWA and RFA; eight studies on MR-guided, laser-induced thermotherapy (LITT); two studies on MR-guided percutaneous cryoablation (PC); and one study on MR-guided percutaneous ethanol injection (PEI). The CA rates in patients who underwent RFA, MWA, LITT, PC, and PEI were 95.60%, 98.86%, 77.78%, 47.92%, and 85.71%, respectively. The most frequent complications were pain (27.66%, 13/47) and postablation syndrome (27.66%, 13/47) in the PC group; pleural effusion (8.11%, 119/1,468) and subcapsular hematoma (2.25%, 33/1,468) in the LITT group; pleural effusion (2.67%, 2/75) in the MWA group; and subcapsular hematoma (4.18%, 20/478) and post-ablation syndrome (2.93%, 14/478) in the RFA group. There were few studies reporting PFS and OS. CONCLUSIONS: MR-guided ablation is a practicable alternative treatment for liver tumors, especially MR-guided RFA and MWA, which have high rates of CA and low occurrences of complications.

A novel three-dimensional template combined with MR-guided 125I brachytherapy for recurrent glioblastoma.

BACKGROUND: At present, the treatment of recurrent glioblastoma is extremely challenging. In this study, we used a novel three-dimensional non-coplanar template (3DNPT) combined with open MR to guide 125I seed implantation for recurrent glioblastoma. The aim of this study was to evaluate the feasibility, accuracy, and effectiveness of this technique. METHODS: Twenty-four patients of recurrent glioblastoma underwent 3DNPT with open MR-guided 125I brachytherapy from August 2017 to January 2019. Preoperative treatment plan and 3DNPT were made according to enhanced isovoxel T1-weighted MR images. 125I seeds were implanted using 3DNPT and 1.0-T open MR imaging guidance. Dosimetry verification was performed after brachytherapy based on postoperative CT/MR fusion images. Preoperative and postoperative dosimetry parameters of D90, V100, V200, conformity index (CI), external index (EI) were compared. The objective response rate (ORR) at 6 months and 1-year survival rate were calculated. Median overall survival (OS) measured from the date of brachytherapy was estimated by Kaplan-Meier method. RESULTS: There were no significant differences between preoperative and postoperative dosimetry parameters of D90, V100, V200, CI, EI (P > 0.05). The ORR at 6 months was 75.0%. The 1-year survival rate was 58.3%. Median OS was 12.9 months. One case of small amount of epidural hemorrhage occurred during the procedure. There were 3 cases of symptomatic brain edema after brachytherapy treatment, including grade three toxicity in 1 case and grade two toxicity in 2 cases. The three patients were treated with corticosteroid for 2 to 4 weeks. The clinical symptoms related to brain edema were significantly alleviated thereafter. CONCLUSIONS: 3DNPT combined with open MR-guided 125I brachytherapy for circumscribed recurrent glioblastoma is feasible, effective, and with low risk of complications. Postoperative dosimetry matched the preoperative treatment plan. The described method can be used as a novel implantation technique for 125I brachytherapy in the treatment of recurrent gliomas. TRIAL REGISTRATION: The study was approved by the Institutional Review Board of Shandong Provincial Hospital Affiliated to Shandong University (NSFC:NO.2017-058), registered 1st July 2017.

MR-guided Percutaneous Biopsy of Focal Hepatic Dome Lesions with Free-hand Combined with MR Fluoroscopy Using 1.0-T Open High-field Scanner.

AIM: To prospectively estimate the safety, feasibility and accuracy of 1.0T open-magnetic resonance (MR)-guided percutaneous biopsy in free-hand of focal lesions located in the hepatic dome. MATERIALS AND METHODS: All percutaneous MR-guided biopsies of the lesions were performed at the Shandong Medical Imaging Research Institute. Thirty-six patients with focal liver lesions located in the hepatic dome measuring 6-36 mm in the maximum diameter were included in this study. Lesions were divided into two groups on the basis of maximum nodule diameters: ≤1.5 cm (n=14) and >1.5 cm (n=22). Surgical pathology of nodules or clinical and imaging follow-up for at least 12 months were used to establish final diagnosis. Diagnostic accuracy, specificity, sensitivity, average procedure time and complications were recorded and analyzed. RESULTS: All obtained samples were sufficient for diagnosis. Accuracy, sensitivity and specificity of MRI-guided percutaneous liver lesions biopsy in diagnosing malignant tumors were 97.2%, 96.7% and 100%, respectively. Accuracy, sensitivity and specificity were 92.9%, 90.9% and 100% for the lesions that were 1.5 cm or smaller in diameter and 100%, 100% and 100% for lesions larger than 1.5 cm in diameter, respectively. There was no significant difference between the two groups (p>0.05). The average procedure time for each pass of the needle from skin entry to the target lesion was 1.1 min and the total procedural time was 28.5 min. Biopsy-induced complications included peri-hepatic hemorrhage in 8.3% (3/36) of cases. No serious complications occurred. CONCLUSION: 1.0T open-MR-guided free-hand percutaneous biopsy is a safe, feasible and highly accurate diagnostic method for pathological diagnosis of focal liver lesions located in the hepatic dome.

[Inhibitory effect of gefitinib and lapatinib on proliferation of HEL cells].

This study was aimed to investigate the therapeutic effect of two molecular targeted therapeutic drugs, tyrosine kinase inhibitors gefitinib and lapatinib, on JAK2 V617F positive myeloproliferative disorders (MPD). The human leukemia cell line (HEL cell line) carrying JAK2 V617F mutation was treated with gefitinib (0.5, 1, 5, 10, 25 µmol/L) and lapatinib (0.5, 1, 2, 4, 8, 16 µmol/L) respectively. MTT method was used to detect HEL cell proliferation. The apoptotic rate and cell cycle were measured by flow cytometry. The results showed that gefitinib could significantly inhibit the proliferation of HEL cells in a dose-dependent manner, it's correlation coefficients for 24 and 48 h were 0.991 and 0.895 respectively. IC(50) at 48 h was 5.4 µmol/L. Gefitinib could effectively induce apoptosis of HEL cells in a dose-dependent manner (r = 0.896). Otherwise, gefitinib could arrest HEL cells at G(0)/G(1) phase. The inhibitory effect of lapatinib was less than gefitinib, it's IC(50) of inhibiting proliferation of HEL cells was 19.6 µmol/L. It is concluded that both gefitinib and lapatinib can inhibit the proliferation of HEL cells. These two tyrosine kinase inhibitors can be used for researching of targeted therapy of JAK2 V617 positive MPD.