Post-treatment Magnetic Resonance Imaging Research Articles

Cryoballoon-Induced Circumferential Pulmonary Vein Fibrosis, Assessed by Late Gadolinium-Enhancement Cardiac Magnetic Resonance Imaging, and Its Correlation with Clinical Atrial Fibrillation Recurrence.

Prior studies evaluating post-atrial fibrillation (AF) ablation pulmonary vein (PV) ostial gaps via magnetic resonance imaging (MRI) have shown circumferential PV fibrosis in a minority of patients, and their correlation with AF recurrence was weak. These studies were mostly based on radio-frequency AF ablations. We aimed to assess cryoballoon ablation-induced PV fibrosis via MRI and its correlation with AF recurrence. This was a prospective study of consecutive patients with symptomatic AF who underwent pre- and post-ablation MRI to assess baseline and ablation-induced fibrosis, respectively. Post-ablation PV gaps were assessed by new semi-quantitative visual analysis assisted by computerized ADAS analysis. AF recurrence monitored via multiple ECGs and event monitoring at 6 and 12 months post ablation. Nineteen patients with 80 PVs were included, age 56 ± 11, with paroxysmal and persistent AF in 17/19 and 2/19 patients, respectively. Baseline MRI showed minimal LA fibrosis. All patients underwent successful cryoballoon PV electrical isolation. Post-ablation MRI revealed circumferential PV fibrosis among 63/80 (78.8%) PVs and partial fibrosis with major gaps among 17/80 (21.2%) PVs. AF recurred within one year in 5/9 (55.5%) patients with partial PV fibrosis, while no AF recurred among the 10 patients in whom all PVs had circumferential fibrosis (p < 0.01). Similarly, there were significantly more PVs without circumferential fibrosis (due to major gaps) among patients with AF recurrence as compared with patients without AF recurrence (42.9% vs. 13.5%; p < 0.01). Cryoballoon AF ablation results in circumferential PV fibrosis in the majority of PVs, as assessed by a new clinically relevant MRI-LGE analysis. Significant correlation was found between major PV gaps on post-ablation MRI and AF recurrence, suggesting that MRI might have the ability to predict AF recurrence.

Efficacy of Percutaneous Image-Guided Rupture of Lumbar Facet Cysts: A Retrospective Study.

Percutaneous rupture of lumbar facet cysts (LFC) is the only nonsurgical treatment which is effective in directly reducing cysts. However, this is not yet a common procedure, and its effectiveness, including the associated complications, remains unclear. Therefore, this study aimed to evaluate the clinical outcomes of percutaneous rupture for LFC and elucidate whether this minimally invasive procedure could become an alternative to surgeries for cases resistant to conservative treatments. This study investigated 57 symptomatic patients with LFC for whom conservative treatments were ineffective and underwent percutaneous rupture of the LFC. All patients were followed up for >2 years posttreatment. Clinical evaluations (visual analogue scale (VAS) and recovery rate calculated using the Japanese Orthopedic Association (JOA) scores) and radiographic evaluations (size of LFC based on magnetic resonance imaging (MRI)) were performed from pretreatment to the final follow-up examination. Successful LFC rupture, without hospitalization and general anesthesia, was achieved in 48 patients. No severe complications occurred during treatment through the last observation. Satisfactory clinical results with significant improvements in the VAS and JOA scores were obtained (VAS: pre/posttreatment: 80.7 mm/11.2 mm, JOA: pre/posttreatment: 15.6 points/26.7 points, and recovery rate: 82.3%). A significant reduction in the LFC was also observed in all cases based on the posttreatment MRI findings. No successful rupture cases required subsequent surgical treatments, although four cases of LFC recurrence required additional percutaneous rupture treatment. Percutaneous rupture for LFC is not only a safe and minimally invasive procedure without any severe complications or requirements for hospitalization and general anesthesia but also a beneficial procedure that can eliminate the need for surgery in cases resistant to conservative treatments.

PET-MRI for evaluation of response to radiochemotherapy in patients with locally advanced cervical cancer

ObjectiveWe aimed to analyze the diagnostic test accuracy of positron emission tomography and a magnetic resonance imaging scan (PET-MRI) fusion in evaluating tumor response after radiochemotherapy in patients with locally...

Underlying Hippocampal Mechanism of Posttraumatic Stress Disorder Treatment Outcome: Evidence From Two Clinical Trials

BackgroundThe hippocampus plays an important role in the pathophysiology of posttraumatic stress disorder (PTSD) and its prognosis. Accumulating findings suggest that individuals with larger pretreatment hippocampal volume are more likely to benefit from PTSD treatment, but the mechanism underlying this effect is unknown. We investigated whether further increase in hippocampal volume during treatment explains the better prognosis of individuals with greater pretreatment hippocampal volume. MethodsWe collected structural magnetic resonance imagesfrom patients with PTSD before and after treatment. We examined whether larger hippocampal volume moderates the effect of increased hippocampal volume during treatment on symptom reduction. Given the relatively small sample sizes of treatment studies with pre- and posttreatment magnetic resonance imaging, we focused on effect sizes and sought to replicate findings in an external sample. We tested our hypothesis in study 1 (N = 38; prolonged exposure therapy) and then tested whether the results could be externally replicated in study 2 (N = 20; ketamine infusion followed by exposure therapy). ResultsFindings from study 1 revealed that increased right hippocampal volume during treatment was associated with greater PTSD symptom reduction only in patients with greater pretreatment right hippocampal volume (p = .03; η2 = 0.13, a large effect). Findings were partially replicated in study 2 for depressive symptoms (p = .034; η2 = 0.25, a very large effect) and for PTSD symptoms (p = .15; η2 = 0.15, a large effect). ConclusionsElucidating increased hippocampal volume as one of the neural mechanisms predictive of therapeutic outcome for individuals with larger pretreatment hippocampal volume may help identify clinical targets for this subgroup.

Abstract TP103: Neuronal Dysfunction And Hemodynamic Disturbance Due To Venous Congestion In Dural Arteriovenous Fistula Revealed By 123 I-iomazenil Single-photon Emission Computed Tomography

Objective: Retrograde leptomeningeal venous drainage (RLVD) of a dural arteriovenous fistula (dAVF) is related to neurological morbidity and unfavorable outcomes. However, the direct damage to cortical neurons by dAVF with RLVD has not been elucidated. 123 I-iomazenil ( 123 I-IMZ) single-photon emission computed tomography (SPECT) can reveal cerebral blood flow and cortical neuronal damage in early and late images, respectively. This study aimed to assess the relationship association between cerebral venous congestive encephalopathy caused by dAVF using 123 I-IMZ SPECT. Methods: Based on the pre- and post-treatment magnetic resonance imaging findings, patients were divided into three groups: normal, edema, and infarction groups. Radioactivities in the early and late images of 123 I-IMZ SPECT were investigated using the affected-to-contralateral side asymmetry ratio (ACR). Results: None of the patients in the normal group showed any symptoms related to venous congestion. In contrast, all the patients in the edema and infarction groups developed neurological symptoms. The ACR in early images in the edema group was significantly lower than that in the normal group and significantly higher than that in the infarction group. The ACR in the late images of the infarction group was significantly lower than those of the normal and edema groups. After treatment, the neurological signs disappeared in the edema group, but only partial improvement was observed in the infarction group. The ACR in early images significantly improved after treatment in the edema group; however, that in late images did not change in any groups. Conclusions: 123 I-IMZ SPECT is useful for evaluating hemodynamic disturbances and neuronal damage in dAVFs. The reduction in early images was correlated with the severity of venous congestive encephalopathy, and the significant reduction in late images is a reliable indicator of irreversible venous infarction caused by RLVD.

Machine learning applied to MRI evaluation for the detection of lymph node metastasis in patients with locally advanced cervical cancer treated with neoadjuvant chemotherapy.

Concurrent cisplatin-based chemotherapy and radiotherapy (CCRT) plus brachytherapy is the standard treatment for locally advanced cervical cancer (LACC). Platinum-based neoadjuvant chemotherapy (NACT) followed by radical hysterectomy is an alternative for patients with stage IB2-IIB disease. Therefore, the correct pre-treatment staging is essential to the proper management of this disease. Pelvic magnetic resonance imaging (MRI) is the gold standard examination but studies about MRI accuracy in the detection of lymph node metastasis (LNM) in LACC patients show conflicting data. Machine learning (ML) is emerging as a promising tool for unraveling complex non-linear relationships between patient attributes that cannot be solved by traditional statistical methods. Here we investigated whether ML might improve the accuracy of MRI in the detection of LNM in LACC patients. We analyzed retrospectively LACC patients who underwent NACT and radical hysterectomy from 2015 to 2020. Demographic, clinical and MRI characteristics before and after NACT were collected, as well as information about post-surgery histopathology. Random features elimination wrapper was used to determine an attribute core set. A ML algorithm, namely Extreme Gradient Boosting (XGBoost) was trained and validated with tenfold cross-validation. The performances of the algorithm were assessed. Our analysis included n.92 patients. FIGO stage was IB2 in n.4/92 (4.3%), IB3 in n.42/92 (45%), IIA1 in n.1/92 (1.1%), IIA2 in n.16/92 (17.4%) and IIB in n.29/92 (31.5%). Despite detected neither at pre-treatment and post-treatment MRI in any patients, LNM occurred in n.16/92 (17%) patients. The attribute core set used to train ML algorithms included grading, histotypes, age, parity, largest diameter of lesion at either pre- and post-treatment MRI, presence/absence of fornix infiltration at pre-treatment MRI and FIGO stage. XGBoost showed a good performance (accuracy 89%, precision 83%, recall 78%, AUROC 0.79). We developed an accurate model to predict LNM in LACC patients in NACT, based on a ML algorithm requiring few easy-to-collect attributes.

The Association of Tissue Change and Treatment Success During High-intensity Focused Ultrasound Focal Therapy for Prostate Cancer

BackgroundTissue preservation strategies have been increasingly used for the management of localized prostate cancer. Focal ablation using ultrasound-guided high-intensity focused ultrasound (HIFU) has demonstrated promising short and medium-term oncological outcomes. Advancements in HIFU therapy such as the introduction of tissue change monitoring (TCM) aim to further improve treatment efficacy. ObjectiveTo evaluate the association between intraoperative TCM during HIFU focal therapy for localized prostate cancer and oncological outcomes 12 mo afterward. Design, setting, and participantsSeventy consecutive men at a single institution with prostate cancer were prospectively enrolled. Men with prior treatment, metastases, or pelvic radiation were excluded to obtain a final cohort of 55 men. InterventionAll men underwent HIFU focal therapy followed by magnetic resonance (MR)-fusion biopsy 12 mo later. Tissue change was quantified intraoperatively by measuring the backscatter of ultrasound waves during ablation. Outcome measurements and statistical analysisGleason grade group (GG) ≥2 cancer on postablation biopsy was the primary outcome. Secondary outcomes included GG ≥1 cancer, Prostate Imaging Reporting and Data System (PI-RADS) scores ≥3, and evidence of tissue destruction on post-treatment magnetic resonance imaging (MRI). A Student's t - test analysis was performed to evaluate the mean TCM scores and efficacy of ablation measured by histopathology. Multivariate logistic regression was also performed to identify the odds of residual cancer for each unit increase in the TCM score. Results and limitationsA lower mean TCM score within the region of the tumor (0.70 vs 0.97, p = 0.02) was associated with the presence of persistent GG ≥2 cancer after HIFU treatment. Adjusting for initial prostate-specific antigen, PI-RADS score, Gleason GG, positive cores, and age, each incremental increase of TCM was associated with an 89% reduction in the odds (odds ratio: 0.11, confidence interval: 0.01–0.97) of having residual GG ≥2 cancer on postablation biopsy. Men with higher mean TCM scores (0.99 vs 0.72, p = 0.02) at the time of treatment were less likely to have abnormal MRI (PI-RADS ≥3) at 12 mo postoperatively. Cases with high TCM scores also had greater tissue destruction measured on MRI and fewer visible lesions on postablation MRI. ConclusionsTissue change measured using TCM values during focal HIFU of the prostate was associated with histopathology and radiological outcomes 12 mo after the procedure. Patient summaryIn this report, we looked at how well ultrasound changes of the prostate during focal high-intensity focused ultrasound (HIFU) therapy for the treatment of prostate cancer predict patient outcomes. We found that greater tissue change measured by the HIFU device was associated with less residual cancer at 1 yr. This tool should be used to ensure optimal ablation of the cancer and may improve focal therapy outcomes in the future.

Abstract 14457: Cardiac MRI Results Following RFA and Cryoballoon Ablation: DECAAF II Subanalysis

Introduction: Radiofrequency (RFA) and cryoballon ablation are standard approaches for rhythm control of atrial fibrillation. Both strategies involve scar formation of the left atrial tissue. To date there have been no studies using post ablation cardiac magnetic resonance imaging (MRI) to assess residual fibrosis and scar created by standard radiofrequency and cryoballoon ablation. Methods: The current study is a sub analysis of the control group of the Delayed-Enhancement MRI Determinant of Successful Catheter Ablation of Atrial Fibrillation trial (DECAAF II). This was a multicenter, randomized, controlled, single blindedtrial that evaluated atrial arrhythmia recurrence (AAR) between PVI alone and PVI plus fibrosis guided ablation. Baseline MRI and 3-month post ablation MRI were obtained to assess lesion and scar formation. Results: Of the 843 patients randomized in the trial, 428 patients were in the control arm that received standard PVI alone. Of those 428 patients, 367 patients (85.7%) underwent RFA and 61 (14.3%) underwent cryoballoon ablation. Average procedure duration was 147 minutes for RFA and 107 minutes for cryoballoon (p = 0.001). The rate of AAR at 451 days was 42.0% in the RFA group and 45.9% in the cryoballoon group (p = 0.66). At the 3-month post MRI the RFA arm had significantly more left atrial scar formation compared to cryoballoon arm (8.8% vs. 6.4%, p = 0.001). Also, the RFA arm had more covered fibrosis (3.6% vs. 2.9%, p = 0.02) and less non-covered fibrosis (14.9% vs. 17.2%, p = 0.05) compared to the cryoballoon arm. The amount of scar formation did not predict AAR (p = 0.07). Conclusions: In this subanalysis of the DECAAF II trial, there was no significant difference in the rate of AAR between RFA and cryoballoon ablation. However, RFA caused significantly more left atrial scar compared to cryoballoon ablation on 3-month post MRI.

Percutaneous MR Imaging–Guided Laser Ablation for the Treatment of Symptomatic Cervicofacial Vascular Malformations

PurposeTo evaluate the safety and effectiveness of percutaneous magnetic resonance (MR) imaging–guided laser ablation for the treatment of symptomatic soft tissue vascular malformations (VMs) in the face and neck. Materials and MethodsAn institutional review board–approved retrospective review was undertaken of all consecutive patients who underwent MR imaging–guided and monitored laser ablation for treatment of symptomatic, cervicofacial soft tissue VM. Preablation and postablation MR imaging findings were independently reviewed. Preablation and postablation VM sizes were documented. Preablation T2 signal characteristics and enhancement patterns as well as postablation change in both signal and enhancement were semiquantitatively assessed. Changes in VM size were compared using a paired t test. ResultsThirteen patients (women, 9; age, 14.5–69.5 years) with 13 VMs were treated for moderate-to-severe pain (n = 4), swelling/mass effect (n = 8), or predominantly cosmesis (n = 1) with 22 total ablation sessions. The baseline maximum VM diameter was 5.7 cm ± 4.2. At baseline, all VMs (100%) demonstrated variable T2-weighted signal hyperintensity and enhancement. For painful VM, the baseline pain score was 8 ± 1. Clinical follow-up was available for 10 patients. Of patients with available follow-up, 3 (100%) treated for moderate-to-severe pain and 7 (100%) treated for swelling/mass effect reported subjective complete or partial symptomatic relief. The patient treated predominantly for cosmetic reasons was lost to follow-up. Two patients (15.4%) experienced minor adverse events by the Society of Interventional Radiology standards. There were no major adverse events. ConclusionsMR imaging–guided and monitored percutaneous laser ablation is safe and effective for the treatment of symptomatic, cervicofacial VMs.

433P Pre-treatment and post-treatment MRI extramural venous invasion, predicts disease-free survival and overall survival, in locally advanced rectal cancer

Presence of extramural venous invasion (EMVI) by magnetic resonance imaging (MRI) is an independent poor prognostic factor in locally advanced rectal cancer (LARC). Nevertheless, the efficacy of both pre-neoadjuvant therapy (NAT) and post-NAT MRI EMVI assessment to predict pathological response and long-term benefit (in terms of disease-free survival (DFS) and overall survival (OS) has not been clearly established. We analyzed 239 patients with LARC receiving NAT with continuous infusion fluorouracil (n=229) or capecitabine (n=10) diagnosed between 2009 and 2019. Baseline and post-NAT MRI EMVI status was assessed in 214 and 173 patients respectively by two radiologists with more than 20-year and 5-year experience. When discrepancies, EMVI status was decided by consensus. Post-surgical pathologic assessment detached good-responders (ypT0N0 and ypT1-2N0) from poor-responders (ypT3Nx or ypTxN1/2). Three-year DFS and 5-year OS were estimated using Kaplan-Meier product-limit method. Baseline EMVI positive (91/214; 42%) was significantly associated with poor pathological response (74/91; 81%) vs. EMVI negative (52/123; 43%), p=0.0001. In the subset of patients evaluated with pre and post MRI, 69/173 (40%) presented positive EMVI at baseline. 21/69 (30%) patients with positive baseline EMVI became negative after therapy (EMVI (+/-)). Three-year DFS was 80.9% in EMVI (-/-), 66.7% in EMVI (+/-), and 45.2% in EMVI (+/+), HR 1.84 (95% CI 1.38-2.44), p=0.000026. Five-year OS was 82.6%, 73.9% and 57.3%, respectively, with HR 1.67 (95% CI 1.26-2.23), p=0.0004. Baseline EMVI accurately predicted pathological efficacy after conventional NAT. Patients that negativized EMVI (+/-) showed significantly better DFS and OS compared to patients that remained positive EMVI (+/+).

Cryoablation of Soft Tissues Low-Flow Vascular Malformations: Clinical Outcomes and Safety.

To report the clinical effectiveness and the safety of cryoablation in first or second-line therapy in symptomatic soft tissues vascular malformation, a mini-invasive therapeutic alternative to sclerotherapy or surgery. This retrospective and monocentric study included patients with symptomatic low-flow vascular malformation. The interventions were carried out under computed tomography (CT) scan, Cone-beam CT (CBCT) and/or USA guidance. Clinical response was evaluated by collecting the Numerical Rating Scale (NRS) for symptoms before and after the ablation. Safety was assessed based on criteria proposed by the Cardiovascular and Interventional Radiological Society of Europe. Imaging response was evaluated with post-ablation Magnetic Resonance Imaging. Twenty-one patients were included. Cryoablation was the first operative treatment for 12 patients (12/21, 57%). The remaining patients had already undergone surgery (2/21, 9%) or one or more sclerotherapy procedures (7/21, 33%).Symptoms assessed by Numerical Rating Scale dropped from a median of 7 [IQR 6-8] before the procedure to a median of 1 [IQR 0-2] after cryoablation (p < 0.001). Half of the patients declared a full effectiveness of cryoablation on their symptoms (11/21). No major complications and four minor adverse events (two skin lesions, two patients with neuropathic pain) were reported (19%). Lesional volume significantly decreased after cryoablation (median from 3.7 cm3 [1-10.4] to 0.25 cm3 [0-2.0], p < 0.001). Cryoablation seems to be a safe and effective first- or second-line therapy for soft tissue vascular malformations.

Comparison of Functional and Structural Neural Network Features in Older Adults With Depression With vs Without Apathy and Association With Response to Escitalopram

Apathy is prevalent among individuals with late-life depression and is associated with poor response to pharmacotherapy, including chronicity and disability. Elucidating brain networks associated with apathy and poor treatment outcomes can inform intervention development. To assess the brain network features of apathy among individuals with late-life depression and identify brain network abnormalities associated with poor antidepressant response. This secondary analysis of a single-group, open-label nonrandomized clinical trial of escitalopram conducted at an outpatient geriatric psychiatry clinic enrolled 40 adults aged 59 to 85 years with major depressive disorder from July 1, 2012, to July 31, 2019. After a 2-week washout period, participants received escitalopram titrated to a target of 20 mg/d for 12 weeks. Baseline and posttreatment magnetic resonance imaging (MRI), clinical, and cognitive assessments were conducted. Functional MRI was used to map group differences in resting state functional connectivity (rsFC) of the salience network, and diffusion MRI connectometry was performed to evaluate pathway-level disruptions in structural connectivity. The Apathy Evaluation Scale was used to quantify apathy, and the Hamilton Depression Rating Scale (HAM-D) was used to quantify the primary outcome of depression severity. Forty participants (26 women [65%]; mean [SD] age, 70.0 [6.6] years [range, 59-85 years]) with depression were included; 20 participants (50%) also had apathy. Relative to nonapathetic participants with depression, those with depression and apathy had lower rsFC of salience network seeds with the dorsolateral prefrontal cortex (DLPFC), premotor cortex, midcingulate cortex, and paracentral lobule and greater rsFC with the lateral temporal cortex and temporal pole (z score >2.7; Bonferroni-corrected threshold of P < .0125). Compared with participants without apathy, those with apathy had lower structural connectivity in the splenium, cingulum, and fronto-occipital fasciculus (t score >2.5; false discovery rate-corrected P = .02). Twenty-seven participants completed escitalopram treatment; 16 (59%) achieved remission (HAM-D score <10). Lower insula-DLPFC/midcingulate cortex rsFC was associated with less symptomatic improvement (HAM-D % change) (β [df] = 0.588 [26]; P = .001) and a higher likelihood of nonremission (odds ratio, 1.041 [95% CI, 1.003-1.081]; P = .04) after treatment and, in regression models, was a mediator of the association between baseline apathy and persistence of depression. Lower dorsal anterior cingulate-DLPFC/paracentral rsFC was associated with residual cognitive difficulties on measures of attention (β [df] = 0.445 [26]; P = .04) and executive function (β [df] = 0.384 [26]; P = .04). This study suggests that disturbances in connectivity between the salience network and other large-scale networks that support goal-directed behavior may give rise to apathy and may be associated with poor response of late-life depression to antidepressant pharmacotherapy. These network disturbances may serve as targets for novel interventions. ClinicalTrials.gov Identifier: NCT01728194.

A Prospective Study of Magnetic Resonance Imaging-guided Focal Salvage High-dose-Rate Brachytherapy for Radiorecurrent Prostate Cancer: Updated Results of 30 Patients

PurposeLimited prospective data on focal salvage high-dose-rate (HDR) prostate brachytherapy is available. We sought to explore the toxicities, health-related quality of life (HRQoL), and efficacy of focal salvage HDR brachytherapy in a prospective clinical trial. This report presents the updated results of previously published data. Methods and MaterialsPatients with locally recurrent prostate cancer after previous external beam radiation therapy and/or brachytherapy were enrolled. Patients received magnetic resonance imaging (MRI)-guided, ultrasound-based focal HDR brachytherapy delivered over 2 fractions of 13.5 Gy delivered 1 to 2 weeks apart. Androgen deprivation therapy (ADT) was not used. ResultsThirty patients were treated between 2012 and 2019. At a median follow-up time of 39 months, the 3-year biochemical failure-free rate was 61.8% (95% confidence interval, 44.0%-86.6%), and the 3-year ADT/salvage therapy-free rate was 86.0% (95% confidence interval, 74.1%-99.8%). Seventeen patients experienced subsequent biochemical failure, 9 received ADT and/or further local salvage, and no patients died of prostate cancer. Of the 28 patients who had posttreatment MRI, 26 had a local treatment response. No acute grade ≥3 genitourinary/gastrointestinal toxicity was observed. One temporary late grade 3 genitourinary toxicity event occurred, but no late grade ≥3 gastrointestinal toxicity was seen. No significant decline in urinary or bowel HRQoL was observed. ConclusionsFocal salvage HDR brachytherapy has a favorable side effect profile, no significant decline in HRQoL, and the 3-year biochemical control rates are in line with those of other salvage options. Early MRI response at the treated site is common, but does not preclude subsequent biochemical failure.

Short-term natural course of esophageal thermal injury after ablation for atrial fibrillation.

Esophageal injury is rare but potentially a devastating complication of atrial fibrillation (AF)ablation.The goal here was to provide insight into the short-term natural history of esophageal thermal injury (ETI) after radiofrequency catheter ablation (RFCA) for AFby esophagogastroduodenoscopy (EGD). We screened patients who underwent RFCA for AF and EGD based on esophageal late gadolinium enhancement (LGE) in postablation magnetic resonance imaging. Patients with ETI diagnosed with EGD were included. We defined severity of ETI according to Kansas City classification: type 1: erythema; type 2: ulcers (2a: superficial; 2b deep); type 3 perforation (3a: perforation; 3b: perforation with atrioesophageal fistula [AEF]). Repeated EGD was performed within 1-14 days after the last EGD if recommended and possible until any certain healing signs (visible reduction in size without deepening of ETI or complete resolution) were observed. ETI was observed in 62 of 378 patients who underwent EGD after RFCA. Out of these 62 patients with ETI, 21% (13) were type 1, 50% (31) were type 2a and 29% (18) were type 2b at the initial EGD. All esophageal lesions, but one type 2b lesion that developed into an AEF, showed signs of healing in repeated EGD studies within 14 days after the procedure. The one type 2b lesion developing into an AEF showed an increase in size and ulcer deepening in repeat EGD 8 days after the procedure. We found that all ETI which did not progress to AEF presented healing signs within 14 days after the procedure and that worsening ETI might be an early signal for developing esophageal perforation.

Shorter distance between the esophagus and the left atrium is associated with higher rates of esophageal thermal injury after radiofrequency ablation.

Esophageal thermal injury (ETI) is a known and potentially serious complication of catheter ablation for atrial fibrillation. We intended to evaluate the distance between the esophagus and the left atrium posterior wall (LAPW) and its association with esophageal thermal injury. A retrospective analysis of 73 patients who underwent esophagogastroduodenoscopy (EGD) after LA radiofrequency catheter ablation for symptomatic atrial fibrillation and pre-ablation magnetic resonance imaging (MRI) was used to identify the minimum distance between the inner lumen of the esophagus and the ablated atrial endocardium (pre-ablation atrial esophageal distance; pre-AED) and occurrence of ETI. Parameters of ablation index (AI, Visitag Surpoint) were collected in 30 patients from the CARTO3 system and compared with assess if ablation strategies and AI further impacted risk of ETI. Pre-AED was significantly larger in patients without ETI than those with ETI (5.23 ± 0.96 mm vs. 4.31 ± 0.75 mm, p < .001). Pre-AED showed high accuracy for predicting ETI with the best cutoff value of 4.37 mm. AI was statistically comparable between Visitag lesion markers with and without associated esophageal late gadolinium enhancement (LGE) detected by postablation MRI in the low-power long-duration ablation group (LPLD, 25-40 W for 10-30 s, 393.16 [308.62-408.86] vs. 406.58 [364.38-451.22], p = .16) and high-power short-duration group (HPSD, 50 W for 5-10 s, 336.14 [299.66-380.11] vs. 330.54 [286.21-384.71], p = .53), respectively. Measuring the distance between the LA and the esophagus in pre-ablation LGE-MRI could be helpful in predicting ETI after LAPW ablation.

The α-RECIST (RECIST 1.1 Combined With Alpha Fetoprotein): A Novel Tool for Identifying Tumor Response of Conversion-Radiotherapy for Unresectable Hepatocellular Carcinoma Before Hepatectomy.

PurposeTo develop a novel criterion based on the response evaluation criteria in solid tumors (RECIST) 1.1 and alpha fetoprotein (AFP) and evaluate its performance in tumor response for patients with unresectable hepatocellular carcinoma (uHCC) receiving conversion-radiotherapy before hepatectomy.MethodFrom June 2012 to December 2020, a total of 39 patients with uHCC, who received intensity-modulated radiotherapy (IMRT) before hepatectomy, were retrospectively included in this study. Pre- and post-treatment contrast-enhanced magnetic resonance imaging (CE-MRI) scans were performed in all patients. Eight modified criteria were developed with the combination of RECIST 1.1, modified RECIST (mRECIST), and the percentage change of AFP, baseline AFP. The endpoint events were recurrence-free survival (RFS).ResultsThe median RFS and OS was 26.5 (IQR, 15.7-43.1), 38.8 (IQR, 18.4-53.6) months. An optimal revised evaluation criterion named α-RECIST (alpha fetoprotein-RECIST 1.1) was developed by combining the RECIST 1.1 with the AFPΔ (cut-off value, 76%). Patients defined as responders by α-RECIST showed significantly better RFS and OS than those defined as non-responders (p = 0.035, 0.048). The other criteria (RECIST 1.1, mRECIST, αΔ-mRECIST, α&Δ-RECIST, α&Δ-mRECIST, αBL-RECIST, αBL-mRECIST, α&BL-RECIST, α&BL-mRECIST) all failed to identify responders from non-responders (p = 0.405, 0.201, 0.773, 0.424, 0.266, 0.060, 0.721, 0.644, 0.910, respectively) when correlated with RFS. Responders according to α-RECIST showed significant better RFS compared to non-responders [HR, 0.31 (95% CI: 0.10, 0.98); p=0.046], but no statistical significance was observed in terms of OS [HR, 0.33 (95% CI: 0.11, 1.05); p = 0.06].ConclusionsPatients identified as responders by α-RECIST provided significant better RFS. The α-RECIST criteria might be a promising tool for identifying tumor response of conversion-radiotherapy for unresectable hepatocellular carcinoma before hepatectomy.

Acute safety and efficacy outcome of pulmonary vein isolation using pulsed field ablation technology

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Pulsed field ablation (PFA) is a new technology for electrical isolation of pulmonary veins (PVI) using electroporation for irreversible cell death. First data imply a very low complication rate in terms of esophageal lesion, phrenic nerve palsy and pulmonary vein stenosis. We present our datas of our first patients concerning acute safety and efficacy. Method 38 patients with paroxysmal and persistent atrial fibrillation (AF) consecutively underwent PFA ablation including complete PVI of all pulmonary veins in all cases (including 14 redo cases ), mean age 68,3 year, and a mean ejection fraction of 56 %, mean CHADSVASC Score 3. 19 patients had paroxysmal AF, in 21 patients additional posterior wall isolation was performed. Additional anatomical and voltage characterization with CARTO was performed before and after ablation. Post ablation, all patients underwent endoscopic evaluation of the esophagus and all eligible patients were screened for silent cerebral lesions (SCL) using cerebral magnetic resonance imaging (MRI). All acute procedure data and complications were documented. Results In all 38 patients effective PVI using only PFA catheter was achieved (100 %) within a mean procedure time of 81±15 min and a mean fluoroscopy time of 18± 5 min. In 2 patients left atrial macroreentrant tachycardia was effectively terminated with PFA pulses in the PV-mitral-annular isthmus region. In no patient an esophageal lesion could be detected (0%). Cerebral MRI was performed in 18 cases and revealed SCLs (47 %) in 5 patients (3 patients with multiple lesions, 2 patiens with 3 lesions, max size of 8 mm). No symptomatic complications including pericardial effusion or access site complications were noted. Conclusion PFA is a highly effective method for acute PVI. No relevant symptomatic complications were noted. Of note, no patient had esophageal injury related to the ablation but 40% of patients undergoing post-ablation MRI had documented SCE. Further data have to be collected to discuss these findings properly.

The added influence of genomics and post-MRI confirmatory biopsy results to MRI results alone on medical decision making for men with favorable risk prostate cancer being considered for active surveillance.

We examined how the results of genomic classifier (GC) or post-magnetic resonance imagingconfirmatory biopsy (pMRI-CBx) influenced management strategy for men with an MRI considering active surveillance (AS). We reviewed the Michigan Urological Surgery Improvement Collaborative registry for men with favorable-risk prostate cancer. Among men with an MRI after the diagnostic biopsy (n = 1162) a subset also had GC (n = 126) or pMRI-CBx (n = 309). Results of MRI, GC, and pMRI-CBx were deemed reassuring (RA) or non-reassuring (Non-RA). We assess the association of the combination of test results obtained with the selection of AS. Proportions were compared with the Fisher's exact test. Multivariable logistic regression models were fit for an association of test results with the selection of AS. The results of pMRI-CBx tended to influence management decisions greater than that of GC, especially in situation where testing results were discordant with the MRI result. Fewer men with a RA MRI and non-RA pMRI-CBx where managed with AS compared with RA MRI alone (31% vs. 86%, p < 0.001). non-RA genomics did not seem to have the same influence on management as non-RA pMRI-CBx as a similar proportion of men with RA MRI and non-RA genomics were managed with AS compared with RA MRI alone (85% vs. 86%, p = 0.753). More men with non-RA MRI and RA pMRI-CBx were managed with AS compared with non-RA MRI alone (89% vs. 40%, p < 0.001). Alternatively, a similar proportion of men with non-RA MRI and RA genomics were managed with AS compared with non-RA MRI alone (42% vs. 40%, p > 0.999). In the multivariable models, pMRI-CBx results influenced the decision for AS versus treatment. In men with newly diagnosed prostate cancer and an MRI, the additional information provided by pMRI-CBx influenced the decision of AS versus treatment, while the addition of GC results were less influential.

Shrinkage of the non-malignant prostate gland volume after receiving incidental radiotherapy for rectal cancer.

BackgroundThe purpose of this study was to assess the impact of coincidental radiotherapy on the volume of the non-malignant prostate gland in rectal cancer patients treated with neo-adjuvant radiotherapy.Materials and methodsIn this retrospective analysis, thirty male patients with rectal cancer who had neoadjuvant radiotherapy met the inclusion criteria. These patients had pre-treatment magnetic resonance imaging (MRI) and at least one post-treatment MRI of the pelvis and the whole of their prostate volume received the full prescribed radiotherapy dose; 45 Gy in 25 fractions (n = 22), 45 Gy in 20 fractions (n = 4) and 25 Gy in 5 fractions (n = 4).ResultsThe median age of this patient cohort was 66 years (range: 30–87). With a median interval between pre-treatment MRI and first MRI post-treatment of 2 months (range: 1–11), the mean prostate volume reduced from 36.1 cm3 [standard deviation (SD) 14.2] pre-radiotherapy to 31.3 cm3 (SD 13.0) post radiotherapy and this difference was significant (p = 0.0004).ConclusionRadiotherapy may cause shrinkage in volume of normal (non-malignant) prostate. Further research is required in this field, since these results may be of some comfort to men contemplating the consequences of radiotherapy on their quality of life. The authors suggest recording flow-rate and international prostate symptom score (IPSS) during rectal radiotherapy as a next step.

Radiomics-based tumor phenotype determination based on medical imaging and tumor microenvironment in a preclinical setting

Background and purposeRadiomics analyses have been shown to predict clinical outcomes of radiotherapy based on medical imaging-derived biomarkers. However, the biological meaning attached to such image features often remains unclear, thus hindering the clinical translation of radiomics analysis. In this manuscript, we describe a preclinical radiomics trial, which attempts to establish correlations between the expression of histological tumor microenvironment (TME)- and magnetic resonance imaging (MRI)-derived image features. Materials & MethodsA total of 114 mice were transplanted with the radioresistant and radiosensitive head and neck squamous cell carcinoma cell lines SAS and UT-SCC-14, respectively. The models were irradiated with five fractions of protons or photons using different doses. Post-treatment T1-weighted MRI and histopathological evaluation of the TME was conducted to extract quantitative features pertaining to tissue hypoxia and vascularization. We performed radiomics analysis with leave-one-out cross validation to identify the features most strongly associated with the tumor’s phenotype. Performance was assessed using the area under the curve (AUCValid) and F1-score. Furthermore, we analyzed correlations between TME- and MRI features using the Spearman correlation coefficient ρ. ResultsTME and MRI-derived features showed good performance (AUCValid,TME = 0.72, AUCValid,MRI = 0.85, AUCValid,Combined=0.85) individual tumor phenotype prediction. We found correlation coefficients of ρ=−0.46 between hypoxia-related TME features and texture-related MRI features. Tumor volume was a strong confounder for MRI feature expression. ConclusionWe demonstrated a preclinical radiomics implementation and notable correlations between MRI- and TME hypoxia-related features. Developing additional TME features may help to further unravel the underlying biology.