Preoperative MRIs Research Articles

Predicting ACL Size in Adolescents

The purpose of this study was to evaluate the predictive value of MRI in determining hamstring autograft size preoperatively for pediatric ACL reconstructions. Children and adolescents from 10-20 years old that had undergone ACL reconstruction using hamstring autograft were identified from 2017-2018. Semitendinosus and gracilis cross-sectional area and diameter were measured on preoperative knee MRIs using the field of interest (FOI) and distance measurement tools. The slice used for measurement was identified as the largest section by the measuring surgeon. Two surgeons independently measured all MRIs. Preoperative demographic data (height, weight, body mass index (BMI), gender) and operative data (graft size) was collected. Data was analyzed by an independent statistician. Ordinal regression analysis was performed to determine the relationship between demographic data and graft size. A Classification and Regression Tree (CART) was constructed to identify predictors for the pre-determined graft sizes of 8 mm. Receiver operating characteristics (ROC) analysis were then created to assess the performance of the predictive model and determine sensitivity and specificity. All analyses were performed using SPSS v. 24 with alpha set at p<0.05 to declare significance. One hundred and ten children (54 boys, 56 girls) were included in this study with an average age of 15.93 years (range 11.81-20.22) and average BMI of 25.98 (range 16.02-40.08). CART analysis determined that if the sum of the cross-sectional areas of the semitendinosus and gracilis tendons were greater than 31.17 mm then 87.5% of children had graft sizes of 8 mm or greater. The ROC analysis determined the model to have an 80% sensitivity and 74% specificity for predicting a graft size of 8 mm or larger. A preoperative summation of the cross-sectional areas of the semitendinosus and gracilis tendons greater than 31.17 mm predicts an intraoperative graft size of 8 mm or larger in 87.5% of children.

Multi-institutional noninvasive in vivo characterization of IDH, 1p/19q, and EGFRvIII in glioma using neuro-Cancer Imaging Phenomics Toolkit (neuro-CaPTk).

BackgroundGliomas represent a biologically heterogeneous group of primary brain tumors with uncontrolled cellular proliferation and diffuse infiltration that renders them almost incurable, thereby leading to a grim prognosis. Recent comprehensive genomic profiling has greatly elucidated the molecular hallmarks of gliomas, including the mutations in isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2), loss of chromosomes 1p and 19q (1p/19q), and epidermal growth factor receptor variant III (EGFRvIII). Detection of these molecular alterations is based on ex vivo analysis of surgically resected tissue specimen that sometimes is not adequate for testing and/or does not capture the spatial tumor heterogeneity of the neoplasm.MethodsWe developed a method for noninvasive detection of radiogenomic markers of IDH both in lower-grade gliomas (WHO grade II and III tumors) and glioblastoma (WHO grade IV), 1p/19q in IDH-mutant lower-grade gliomas, and EGFRvIII in glioblastoma. Preoperative MRIs of 473 glioma patients from 3 of the studies participating in the ReSPOND consortium (collection I: Hospital of the University of Pennsylvania [HUP: n = 248], collection II: The Cancer Imaging Archive [TCIA; n = 192], and collection III: Ohio Brain Tumor Study [OBTS, n = 33]) were collected. Neuro-Cancer Imaging Phenomics Toolkit (neuro-CaPTk), a modular platform available for cancer imaging analytics and machine learning, was leveraged to extract histogram, shape, anatomical, and texture features from delineated tumor subregions and to integrate these features using support vector machine to generate models predictive of IDH, 1p/19q, and EGFRvIII. The models were validated using 3 configurations: (1) 70–30% training–testing splits or 10-fold cross-validation within individual collections, (2) 70–30% training–testing splits within merged collections, and (3) training on one collection and testing on another.ResultsThese models achieved a classification accuracy of 86.74% (HUP), 85.45% (TCIA), and 75.15% (TCIA) in identifying EGFRvIII, IDH, and 1p/19q, respectively, in configuration I. The model, when applied on combined data in configuration II, yielded a classification success rate of 82.50% in predicting IDH mutation (HUP + TCIA + OBTS). The model when trained on TCIA dataset yielded classification accuracy of 84.88% in predicting IDH in HUP dataset.ConclusionsUsing machine learning algorithms, high accuracy was achieved in the prediction of IDH, 1p/19q, and EGFRvIII mutation. Neuro-CaPTk encompasses all the pipelines required to replicate these analyses in multi-institutional settings and could also be used for other radio(geno)mic analyses.

Breast and tumor volumes on 3D-MRI and their impact on the performance of a breast conservative surgery (BCS).

Breast conservation rate is being increasingly used nowadays as a marker of breast cancer care among hospitals. Searching for the ideal technique to predict the feasibility of BCS is ongoing. For this matter, the preoperative MRIs of 169 patients operated with radical or conservative surgery were reviewed. We estimated the tumor volume (TV) and breast volume (BV) on enhanced 3D-MRI and compared the tumor-to-breast volume ratio (TV/BV) in both groups. The mean ratio was 9.5% in the mastectomy group and 1.7% in the BCS group. A tumor-to-breast volume ratio less than 4% seemed to favor the adoption of a conservative option. Our data suggest that preoperative 3D-MRI can orient the surgical approach by assessing the TV/BV ratio, increasing lumpectomy rates with clear margins and good cosmetic outcome.

RARE-11. QUANTITATIVE MR IMAGING FEATURES ASSOCIATED WITH UNIQUE TRANSCRIPTIONAL CHARACTERISTICS IN PEDIATRIC ADAMANTINOMATOUS CRANIOPHARYNGIOMA: A POTENTIAL GUIDE FOR THERAPY

METHODSThrough the Advancing Treatment for Pediatric Craniopharyngioma (ATPC) consortium we accumulated preoperative MRIs and tumor RNA for 50 unique ACP patients. MRIs were assessed quantitatively for 28 different features and analyzed using Multiple Factor Analysis (MFA) and optimal clustering was determined via maximization of Bayesian Information Criterion (BIC). Following bulk RNAseq, differential expression and pathway enrichment were performed using standard methodologies (i.e., DESeq2 and GSEA).RESULTSMRI features were well represented in the first 3 dimensions of MFA (variance explained=67.32%); specifically tumor/cyst size, ventricular size, and cyst fluid diffusivity. Using this three-way axis, we identified 3 patient subgroups. Transcriptional differences between these subgroups indicated one group was enriched for DNA damage response and MYC related pathways, one group enriched for SHH, and one group enriched for WNT/β-catenin and EMT-related pathways.CONCLUSIONThis preliminary work suggests that there may be unique gene expression variants within ACP, which may be identified preoperatively using easily quantifiable MRI parameters. These radiogenomic signatures could provide prognostic information and/or guidance in the selection of antitumor therapies for children with ACP.

NCOG-03. FACTORS ASSOCIATED WITH ADJACENT LEVEL TUMOR PROGRESSION IN PATIENTS RECEIVING SEPARATION SURGERY FOLLOWED BY SPINE STEREOTACTIC RADIOSURGERY FOR METASTATIC EPIDURAL SPINAL CORD COMPRESSION

Abstract INTRODUCTION Separation surgery followed by spine stereotactic radiosurgery (SSRS) has been shown to achieve favorable rates of local tumor control and patient-reported outcomes in patients with metastatic epidural spinal cord compression (MESCC). If left untreated, MESCC causes severe pain, progressive neurological impairment, and eventual paraplegia with a median survival of 3-6 months. The present study aimed to identify factors associated with adjacent level progression and examine its impact on overall survival (OS) in this population. METHODS This study included 39 patients who received separation surgery followed by SSRS for MESCC. Preoperative, postoperative, and post-SSRS MRIs were used to measure amount of epidural disease, amount of local bone marrow involvement, and adjacent level epidural (AEP) and osseous (AOP) progression. Factors associated with AEP and AOP were examined using the log-rank test and cox proportional hazards modeling. RESULTS Median OS in our cohort was 14.7 mo (2.07-96.3). AEP and AOP were observed in 4/39 (10.3%) and 16/39 (41.0%) patients at a mean of 6.1±5.4 mo and 5.3±5.3 mo post-SSRS, respectively. AEP (7.52 vs. 17.1 mo, p = 0.014) and AOP (13.0 vs. 17.1 mo, p = 0.047) were each significantly associated with decreased OS. Factors associated with AEP included primary tumor histology, low-dose hypofractionated SSRS, increased time from surgery to SSRS, and greater amount of local epidural disease preoperatively (p &amp;lt; 0.05). Factors associated with AOP included greater amount of local bone marrow infiltration by tumor pre- and postoperatively and greater amount of local epidural disease postoperatively (p &amp;lt; 0.05). Primary tumor histology and increased time from surgery to SSRS were associated with AOP by trend (p &amp;lt; 0.10). CONCLUSION This study identifies factors associated with adjacent level progression and shows that AEP and AOP are associated with shorter OS in patients receiving separation surgery followed by SSRS for MESCC.

MGMT methylation may benefit overall survival in patients with moderately vascularized glioblastomas

ObjectivesTo assess the combined role of tumor vascularity, estimated from perfusion MRI, and MGMT methylation status on overall survival (OS) in patients with glioblastoma.MethodsA multicentric international dataset including 96 patients from NCT03439332 clinical study were used to study the prognostic relationships between MGMT and perfusion markers. Relative cerebral blood volume (rCBV) in the most vascularized tumor regions was automatically obtained from preoperative MRIs using ONCOhabitats online analysis service. Cox survival regression models and stratification strategies were conducted to define a subpopulation that is particularly favored by MGMT methylation in terms of OS.ResultsrCBV distributions did not differ significantly (p > 0.05) in the methylated and the non-methylated subpopulations. In patients with moderately vascularized tumors (rCBV < 10.73), MGMT methylation was a positive predictive factor for OS (HR = 2.73, p = 0.003, AUC = 0.70). In patients with highly vascularized tumors (rCBV > 10.73), however, there was no significant effect of MGMT methylation (HR = 1.72, p = 0.10, AUC = 0.56).ConclusionsOur results indicate the existence of complementary prognostic information provided by MGMT methylation and rCBV. Perfusion markers could identify a subpopulation of patients who will benefit the most from MGMT methylation. Not considering this information may lead to bias in the interpretation of clinical studies.Key Points• MRI perfusion provides complementary prognostic information to MGMT methylation.• MGMT methylation improves prognosis in glioblastoma patients with moderate vascular profile.• Failure to consider these relations may lead to bias in the interpretation of clinical studies.

Radiomics risk score may be a potential imaging biomarker for predicting survival in isocitrate dehydrogenase wild-type lower-grade gliomas.

Isocitrate dehydrogenase wild-type (IDHwt) lower-grade gliomas of histologic grades II and III follow heterogeneous clinical outcomes, which necessitates risk stratification. We aimed to evaluate whether radiomics from MRI would allow prediction of overall survival in patients with IDHwt lower-grade gliomas and to investigate the added prognostic value of radiomics over clinical features. Preoperative MRIs of 117 patients with IDHwt lower-grade gliomas from January 2007 to February 2018 were retrospectively analyzed. The external validation cohort consisted of 33 patients from The Cancer Genome Atlas. A total of 182 radiomic features were extracted. Radiomics risk scores (RRSs) for overall survival were derived from the least absolute shrinkage and selection operator (LASSO) and elastic net. Multivariable Cox regression analyses, including clinical features and RRSs, were performed. The integrated areas under the receiver operating characteristic curves (iAUCs) from models with and without RRSs were calculated for comparisons. The prognostic value of RRS was assessed in the validation cohort. The RRS derived from LASSO and elastic net independently predicted survival with hazard ratios of 9.479 (95% confidence interval [CI], 3.220-27.847) and 6.148 (95% CI, 3.009-12.563), respectively. Those RRSs enhanced model performance for predicting overall survival (iAUC increased to 0.780-0.797 from 0.726), which was externally validated. The RRSs stratified IDHwt lower-grade gliomas in the validation cohort with significantly different survival. Radiomics has the potential for noninvasive risk stratification and can improve prediction of overall survival in patients with IDHwt lower-grade gliomas when integrated with clinical features. • Isocitrate dehydrogenase wild-type lower-grade gliomas with histologic grades II and III follow heterogeneous clinical outcomes, which necessitates further risk stratification. • Radiomics risk scores derived from MRI independently predict survival even after incorporating strong clinical prognostic features (hazard ratios 6.148-9.479). • Radiomics risk scores derived from MRI have the potential to improve survival prediction when added to clinical features (integrated areas under the receiver operating characteristic curves increased from 0.726 to 0.780-0.797).

Utilization of breast MRI and breast MRI-guided biopsy in clinical practice: results of a survey in Qu\xe9bec and France

BackgroundTo investigate the practice regarding breast MRI exams and breast MRI-guided biopsies in two countries with different health care systems, France and Québec. A 12-item questionnaire was distributed online among radiologists from France and Québec, attempting to determine: demographic characteristics and breast MRI diagnostic and MRI-guided practices (indications, workload, availability, and waiting time assessment).ResultsOne hundred and seventy radiologists (France, 132 respondents (28.5%); Quebec, 38 respondents (35.2%)) participated in the survey, most of them based in non-academic centers. Thirty-eight percent of Quebec and 2.3% of French radiologists did not perform breast MRI in their daily practice. Nearly 50% of French and Quebec respondents interpreted 1–10 breast MRI exams per week. Decision-making factors of preoperative MRI were similar in both countries (pathology, age, and breast density), with a heavier emphasis placed on the surgeon’s opinion in Quebec (47.8% versus 21.8% (p = 0.009)). Quebec demonstrated a higher waiting time than France (1–2 weeks in 40% versus less than 1 week in 40%). MRI-guided breast biopsies (less than 5 MRI-guided biopsies per week) were being performed by a minority of the respondents (36% in France and 43% in Québec).ConclusionMost of radiologists performing breast MRIs work in non-academic institutions in both countries. Waiting time is higher in Quebec, but most of preoperative breast MRIs are performed within 3 weeks in both countries. The surgeon plays an important role in recommending preoperative MRI in Quebec. MRI-guided breast biopsies are not widely available in both countries.

A Practical Pre-Operative Predictive Model for Determining Hamstring Autograft Size for Anterior Cruciate Ligament Reconstruction in Children and Adolescents

Objectives:The most commonly used graft for pediatric and adolescent anterior cruciate ligament (ACL) reconstruction is the hamstring autograft. Recent evidence has suggested that graft sizes less than 8 mm and age less than 20 years old are the most significant factors influencing graft failure. Additionally, studies examining the role of augmenting smaller grafts with allograft have demonstrated mixed results and potentially increased failure rates. Efforts to predict hamstring size preoperatively using MRI and ultrasound in the adult population have shown promise. However, there have been no studies in an entirely pediatric population. The purpose of this study was to evaluate the predictive value of MRI in determining hamstring autograft size preoperatively for pediatric ACL reconstructions.Methods:Children and adolescents from 10-20 years old that had undergone ACL reconstruction using hamstring autograft were identified from 2017-2018. Semitendinosus and gracilis cross-sectional area and diameter were measured on preoperative knee MRIs using the field of interest (FOI) and distance measurement tools. The slice used for measurement was identified as the largest section by the measuring surgeon. Two surgeons independently measured all MRIs. Preoperative demographic data (height, weight, body mass index (BMI), gender) and operative data (graft size) was collected. Data was analyzed by an independent statistician. Ordinal regression analysis was performed to determine the relationship between demographic data and graft size. A Classification and Regression Tree (CART) was constructed to identify predictors for the pre-determined graft sizes of 8 mm. Receiver operating characteristics (ROC) analysis were then created to assess the performance of the predictive model and determine sensitivity and specificity. All analyses were performed using SPSS v. 24 with alpha set at p<0.05 to declare significance.Results:One hundred and ten children (54 boys, 56 girls) were included in this study with an average age of 15.93 years (range 11.81-20.22) and average BMI of 25.98 (range 16.02-40.08). CART analysis determined that if the sum of the cross-sectional areas of the semitendinosus and gracilis tendons were greater than 31.17 mm then 87.5% of children had graft sizes of 8 mm or greater. The ROC analysis determined the model to have an 80% sensitivity and 74% specificity for predicting a graft size of 8 mm or larger.Conclusion:A preoperative summation of the cross-sectional areas of the semitendinosus and gracilis tendons greater than 31.17 mm predicts an intraoperative graft size of 8 mm or larger in 87.5% of children.Figure 1.Table 1:Magnetic resonance imaging (MRI) measurements comparing children with graft sizes less than 8 mm with those 8 mm or greater. 95% Confidence Interval Mean Lower Upper P-value Height (cm)<8162.28159.66164.908+169.02166.56171.47<0.001Weight (kg)<867.3562.2772.438+76.8871.1682.600.014BMI<825.3823.7726.998+26.5725.1228.020.274Age (years)<815.8915.3916.388+15.9715.5716.370.793Semitendinosus<815.8314.8616.81 Cross-sectional Area8+19.1518.1420.16<0.001Semitendinosus Diameter<84.824.664.99 (Anteroposterior)8+5.174.975.370.009Semitendinosus Diameter<84.023.844.21 (Medial/lateral)8+4.494.334.65<0.001Gracillis<89.849.2210.46 Cross-sectional Area8+11.3310.6811.980.001Gracillis Diameter<84.224.094.36 (Anteroposterior)8+4.584.364.800.01Gracillis Diameter<82.872.752.99 (Medial/lateral)8+3.102.973.220.013Semitendinosus + Gracillis<825.6724.3227.02 Cross-sectional Area8+30.4829.0331.93<0.001Diameter Sum<815.9415.5516.338+17.3316.9017.77<0.001

Performance of preoperative breast MRI based on breast cancer molecular subtype

PurposeTo assess the performance of preoperative breast MRI biopsy recommendations based on breast cancer molecular subtype. MethodsAll preoperative breast MRIs at a single academic medical center from May 2010 to March 2014 were identified. Reports were reviewed for biopsy recommendations. All pathology reports were reviewed to determine biopsy recommendation outcomes. Molecular subtypes were defined as Luminal A (ER/PR+ and HER2-), Luminal B (ER/PR+ and HER2+), HER2 (ER-, PR- and HER2+), and Basal (ER-, PR-, and HER2-). Logistic regression assessed the probability of true positive versus false positive biopsy and mastectomy versus lumpectomy. ResultsThere were 383 patients included with a molecular subtype distribution of 253 Luminal A, 44 Luminal B, 20 HER2, and 66 Basal. Two hundred and thirteen (56%) patients and 319 sites were recommended for biopsy. Molecular subtype did not influence the recommendation for biopsy (p = 0.69) or the number of biopsy site recommendations (p = 0.30). The positive predictive value for a biopsy recommendation was 42% overall and 46% for Luminal A, 43% for Luminal B, 36% for HER2, and 29% for Basal subtype cancers. The multivariate logistic regression model showed no difference in true positive biopsy rate based on molecular subtype (p = 0.78). Fifty-one percent of patients underwent mastectomy and the multivariate model demonstrated that only a true positive biopsy (odds ratio: 5.3) was associated with higher mastectomy rates. ConclusionBreast cancer molecular subtype did not influence biopsy recommendations, positive predictive values, or surgical approaches. Only true positive biopsies increased the mastectomy rate.

To scan or not to scan: An evaluation of preoperative MRI use in primary breast cancer assessments.

e14146 Background: Breast cancer (BC) is the most common invasive cancer in adult females.The role of preoperative MRI in assessing the extent of primary breast cancer remains controversial. This study’s objective is to determine if MRIs performed after the diagnosis of invasive/non-invasive-breast cancer will identify additional breast cancers. We hypothesize that preoperative MRIs will result in the discovery of additional significant lesions, leading to changes in surgical treatment. Methods: A retrospective study of 389 BC patient charts were reviewed, dated from January 2000- July 2019. Files were collected from an office in the Breast Cancer Surgery Department. Information on each patient’s imaging studies, treatment, demographics, surgery, and pathology were collected and stored in anonline cloud system. Summary statistics, including proportions, percentages, and difference of proportion hypothesis tests were utilized to interpret the data. All statistical tests were conducted at a 95% confidence interval. Results: We reviewed the charts of 335 patients that met eligibility criteria. In 221 newly diagnosed cancers, a preoperative MRI was taken before treatment. 127 cancers (57.5%)showed additional finding.In BC patients with additional preoperative MRI findings, we observed 61.4%true positive and 38.6%false positive results. These values are comparable to prior studies.We determined that the treatment plan was altered in 17.6%of all patients who received an MRI and in 30.7%of patients with a true positive MRI finding, which is also consistent with previous literature.A majority of the treatment changes were from Lumpectomy to Mastectomy. Conclusions: Literature on MRI use in BC diagnosis exists; our study differs by focusing on newly diagnosed breast cancers.We discovered 35.3% of preoperative MRIs identified a true additional finding in known breast cancer. In addition, our true positive rate (61.4%) and false positive rate (22.2%) of MRI findings is comparable to those of previous studies. Plans were changed in 30.7% of additional findings supporting the idea that preoperative MRI studies are useful when organizing surgical treatment. Further studies to demonstrate the impact on local recurrence rates and overall survival, may clarify the true role of pre-operative MRI in these cases.

Femoral and tibial bone bruise volume is not correlated with ALL injury or rotational instability in patients with ACL-deficient knee.

Some researchers have suggested that bone bruises are evidence of rotational instability. The hypothesis was that the extent of lateral bone edema is correlated with the presence of an anterolateral ligament (ALL) injury. The main objective was to determine whether there was a correlation between the presence of an ALL injury the extent of bone bruises. A prospective diagnostic study enrolled all the patients who suffered an acute anterior cruciate ligament (ACL) who were operated on within 8weeks. The extent of bone bruising according to the ICRS classification was measured on preoperative MRIs by two independent blinded raters twice with an interval of 4weeks. Dynamic ultrasonography (US) to look for ALL injury and the pivot shift test were performed before the ACL surgery. The correlation between ALL injury and bone bruises, and the correlation between an ALL injury and a high-grade pivot shift test were determined. Sixty-one patients were included; 52% of patients had an ALL injury on US. The extent of lateral bone bruise was not related to the presence of an ALL injury, nor related to the presence of a high-grade pivot shift. A grade 2 or 3 pivot shift was significantly correlated with an ALL injury (p < 0.0001). Inter- and intra-rater reliability for the bone bruise rating was excellent. The extent of lateral bone bruise is not correlated with ALL injury or a high-grade pivot shift; thus, it is not correlated with rotational instability of the knee. II.

Diagnostic performance of the LR-M criteria and spectrum of LI-RADS imaging features among primary hepatic carcinomas.

To evaluate the diagnostic performance of LR-M criteria for differentiating hepatocellular carcinoma, intrahepatic mass-forming cholangiocarcinoma, and combined hepatocellular-cholangiocarcinoma and to compare the imaging features of each type. In this retrospective study, 110 patients were surgically diagnosed with cholangiocarcinoma (n = 67) and combined hepatocellular-cholangiocarcinoma (n = 43) at a single tertiary hospital between 2013 and 2018. Among them, those with risk factors were enrolled (16 cholangiocarcinomas and 33 combined hepatocellular-cholangiocarcinomas). Forty-nine other patients with size-matched hepatocellular carcinoma were selected as a control group. Two independent readers evaluated the imaging findings of the preoperative MRIs based on LI-RADS version 2018 and assigned an LI-RADS category. The diagnostic performance of the LR-M criteria for diagnosing cholangiocarcinoma or combined hepatocellular-cholangiocarcinoma was evaluated, and the imaging features were compared. The imaging findings of the tumors in patients without risk factors (51 cholangiocarcinomas and 10 combined hepatocellular-cholangiocarcinomas) were evaluated for subgroup analysis. In the non-hepatocellular carcinoma group, 33 patients were categorized into LR-M and 14 patients into LR-5 (67.3% and 28.6%, respectively), while 5 patients with hepatocellular carcinoma were categorized into LR-M and 38 patients into LR-5 (10.2% and 77.6%, respectively). Sensitivity and specificity of the LR-M criteria were 67.3% and 89.8%, respectively. When more than two LR-M features were present, cholangiocarcinoma or combined hepatocellular-cholangiocarcinoma were suggested with a specificity of 95.9%. The diagnostic performance of the LR-M criteria is acceptable with moderate sensitivity and high specificity for both cholangiocarcinoma and combined hepatocellular-cholangiocarcinoma. Imaging findings of primary hepatic carcinomas should be understood as a spectrum.

Lateral meniscal slope negatively affects post-operative anterior tibial translation at 1 year after primary anterior cruciate ligament reconstruction.

The aim of this study was to assess the correlation between posterior tibial slope and meniscal slope over postoperative anterior tibial translation during the first 18months after primary anterior cruciate ligament (ACL) reconstruction. The main hypothesis was that PTS and MS would be positively correlated with post-operative ATT-SSD after ACL reconstruction. Patients (28 males and 15 females) with confirmed ACL tears were selected from an in-house registry and included if they were over 16years old, had primary ACL-reconstruction and healthy contralateral knee. Patients meeting one of the following criteria were excluded: previous knee surgeries, intraarticular fractures, associated ligamentous lesions, previous or concomitant meniscectomy or extraarticular procedures. Lateral posterior tibial slope, medial posterior tibial slope, lateral meniscal slope and medial meniscal slope were measured using preoperative MRIs. The side-to-side-difference in anterior tibial translation was evaluated 9-18months postoperatively. Forty-three patients were included, (28 males/15 females; mean age 25 ± 8years). Mean postoperative anterior tibial translation was 1.0 ± 1.1mm at a mean time of 12 ± 1months. Mean slope values were: lateral posterior tibial slope 4.7° ± 2.2°, medial posterior tibial slope 4.0° ± 2.8°, lateral meniscal slope 3.0° ± 2.2° and medial meniscal slope 2.0° ± 2.8°. The anterior tibial translation was significantly correlated with lateral meniscal slope (r = 0.63; p < 0.01). For each 1° increase in lateral meniscal slope, a 0.3mm 95% CI [0.2, 0.4] (p < 0.01) increase in anterior tibial translation was observed. A lateral meniscal slope greater or equal to 4.0° was estimated as optimal threshold for increased risk of abnormal side-to-side difference in postoperative anterior tibial translation (≥ 1.2mm). The lateral meniscal slope was positively correlated to side-to-side difference in anterior tibial translation after primary ACL reconstruction. A lateral meniscal slope greater or equal to 4.0° was detected as threshold for an increased risk of abnormal side-to-side difference in postoperative anterior tibial translation in patients who underwent primary ACL reconstruction. This confirms that soft tissue slopes have an impact on the outcomes after reconstructive surgery. Level of evidence III.

Prognostic Value of Preoperative MRI Metrics for Diffuse Lower-Grade Glioma Molecular Subtypes.

Despite the improved prognostic relevance of the 2016 WHO molecular-based classification of lower-grade gliomas, variability in clinical outcome persists within existing molecular subtypes. Our aim was to determine prognostically significant metrics on preoperative MR imaging for lower-grade gliomas within currently defined molecular categories. We undertook a retrospective analysis of 306 patients with lower-grade gliomas accrued from an institutional data base and The Cancer Genome Atlas. Two neuroradiologists in consensus analyzed preoperative MRIs of each lower-grade glioma to determine the following: tumor size, tumor location, number of involved lobes, corpus callosum involvement, hydrocephalus, midline shift, eloquent cortex involvement, ependymal extension, margins, contrast enhancement, and necrosis. Adjusted hazard ratios determined the association between MR imaging metrics and overall survival per molecular subtype, after adjustment for patient age, patient sex, World Health Organization grade, and surgical resection status. For isocitrate dehydrogenase (IDH) wild-type lower-grade gliomas, tumor size (hazard ratio, 3.82; 95% CI, 1.94-7.75; P < .001), number of involved lobes (hazard ratio, 1.70; 95% CI, 1.28-2.27; P < .001), hydrocephalus (hazard ratio, 4.43; 95% CI, 1.12-17.54; P = .034), midline shift (hazard ratio, 1.16; 95% CI, 1.03-1.30; P = .013), margins (P = .031), and contrast enhancement (hazard ratio, 0.34; 95% CI, 0.13-0.90; P = .030) were associated with overall survival. For IDH-mutant 1p/19q-codeleted lower-grade gliomas, tumor size (hazard ratio, 2.85; 95% CI, 1.06-7.70; P = .039) and ependymal extension (hazard ratio, 6.34; 95% CI, 1.07-37.59; P = .042) were associated with overall survival. MR imaging metrics offers prognostic information for patients with lower-grade gliomas within molecularly defined classes, with the greatest prognostic value for IDH wild-type lower-grade gliomas.

A PRACTICAL PRE-OPERATIVE PREDICTIVE MODEL FOR DETERMINING HAMSTRING AUTOGRAFT SIZE FOR ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION IN CHILDREN AND ADOLESCENTS

Background:The most commonly used graft for pediatric/adolescent anterior cruciate ligament (ACL) reconstruction is the hamstring autograft. Recent evidence has suggested that graft sizes less than 8 mm and age less than 20 years old are the most significant factors influencing graft failure. Additionally, studies examining the role of augmenting smaller grafts with allograft have demonstrated mixed results and potentially increased failure rates. Efforts to predict hamstring size preoperatively using MRI and ultrasound in the adult population have shown promise. However, there have been no studies in an entirely pediatric population.Hypothesis/Purpose:The purpose of this study was to evaluate the predictive value of MRI in determining hamstring autograft size preoperatively for pediatric ACL reconstructions.Methods:Children and adolescents from 10-20 years old that had undergone ACL reconstruction using hamstring autograft were identified from 2017-2018. Semitendinosus and gracilis cross-sectional area and diameter were measured on preoperative knee MRIs using the field of interest and distance measurement tools. The slice used for measurement was identified as the largest section by the measuring surgeon. Two surgeons independently measured all MRIs. Preoperative demographic data (height, weight, body mass index (BMI), gender) and operative data (graft size) was collected. Ordinal regression analysis was performed to determine the relationship between demographic data and graft size. A Classification and Regression Tree (CART) was constructed to identify predictors for the pre-determined graft sizes of 8 mm. Receiver operating characteristics (ROC) analysis were then created to assess the performance of the predictive model and determine sensitivity and specificity.Results:One hundred and ten children (54 boys, 56 girls) were included in this study with an average age of 15.93 years (range 11.81-20.22) and average BMI of 25.98 (range 16.02-40.08). CART analysis determined that if the sum of the cross-sectional areas of the semitendinosus and gracilis tendons were greater than 31.17 mm then 87.5% of children had graft sizes of 8 mm or greater. The ROC analysis determined the model to have an 80% sensitivity and 74% specificity for predicting a graft size of 8 mm or larger.Conclusion:A preoperative summation of the cross-sectional areas of the semitendinosus and gracilis tendons greater than 31.17 mm predicts an intraoperative graft size of 8 mm or larger in 87.5% of children.Table 1:Demographic data comparing children with graft sizes less than 8 mm with those 8 mm or greater. Table 2:Magnetic resonance imaging (MRI) measurements comparing children with graft sizes less than 8 mm with those 8 mm or greater. Figure 1:Magnetic resonance imaging (MRI) of a right knee cross-section demonstrating the measurement technique for determining the cross-sectional area of the semitendinosus and gracillis tendons using the field of interest (FOI) tool.

Texture analysis on preoperative contrast-enhanced magnetic resonance imaging identifies microvascular invasion in hepatocellular carcinoma

BackgroundRadiomic texture analysis quantifies tumor heterogeneity. The aim of this study is to determine if radiomics can predict biologic aggressiveness in HCC and identify tumors with MVI. MethodsSingle-center, retrospective review of HCC patients undergoing resection/ablation with curative intent from 2009 to 2017. DICOM images from preoperative MRIs were analyzed with texture analysis software. Texture analysis parameters extracted on T1, T2, hepatic arterial phase (HAP) and portal venous phase (PVP) images. Multivariate logistic regression analysis evaluated factors associated with MVI. ResultsMVI was present in 52.2% (n = 133) of HCCs. On multivariate analysis only T1 mean (OR = 0.97, 95%CI 0.95–0.99, p = 0.043) and PVP entropy (OR = 4.7, 95%CI 1.37–16.3, p = 0.014) were associated with tumor MVI. Area under ROC curve was 0.83 for this final model. Empirical optimal cutpoint for PVP tumor entropy and T1 tumor mean were 5.73 and 23.41, respectively. At these cutpoint values, sensitivity was 0.68 and 0.5, respectively and specificity was 0.64 and 0.86. When both criteria were met, the probability of MVI in the tumor was 87%. ConclusionTumor entropy and mean are both associated with MVI. Texture analysis on preoperative imaging correlates with microscopic features of HCC and can be used to predict patients with high-risk tumors.

36: Correlation of endometriosis on preoperative MRI and surgical pathology

The aim of this study is to assess whether the use of MRI as part of preoperative workup in the setting of patients with chronic pelvic pain and presumed diagnosis of endometriosis is predictive of pathology-proven endometriosis. Retrospective chart review of patients operated on by one fellowship trained minimally invasive gynecologist over the course of 16 months was completed. All surgical cases performed at one of two tertiary hospitals between November 2017 and February 2019 were reviewed and laparoscopic cases were identified. Laparoscopic cases in which a preoperative MRI was performed were then identified. These cases were reviewed to assess for presence or absence of: (1) a preoperative prediction of endometriosis, (2) identification of endometriosis on preoperative MRI, and (3) surgical diagnosis of endometriosis based on intraoperative findings or surgical pathology. 25 surgical cases had MRI performed preoperatively. 10 predicted endometriosis preoperatively and all had pathology confirmed endometriosis. Of the patients with positive MRIs and positive pathology for endometriosis, 5(50%) were stage 4, 3(30%) stage 3, 1(10%) stage 2, and 1(10%) stage 1. Of the 15 of the preoperative MRIs that did not predict endometriosis, 7 had pathology confirmed endometriosis and 8 were pathology confirmed negative for endometriosis. Of the patients with negative MRIs and positive pathology for endometriosis, 4(57.1%) were stage 1, 2(28.6%) stage 2, and 1(14.3%) stage 3. A Fisher exact test for equality of accuracy in the patients showed that patients who had a positive MRI had a significantly higher endometriosis pathologic diagnosis accuracy than patients who had a negative MRI (p<0.05). Ultrasound is the most common form of imaging done in the setting of suspected endometriosis. The advanced dynamic ultrasound techniques in the literature for endometriosis assessment is not universally available in the US. Preoperative MRI may be used as part of the workup of patients with presumed endometriosis because it allows for evaluation of all pelvic compartments as well as increased accuracy in suspected diagnosis. MRI is also less susceptible to interobserver variability that can be associated with ultrasound, which is dependent on the technician and the radiologist. Preoperative MRI was predictive for both presence and absence of endometriosis. The MRI was more predictive of advanced stage endometriosis. Advanced disease endometriosis is best treated by a surgeon with advanced surgical skills and experience with endometriosis so that the patient has clear expectations of outcomes and recurrence, to optimize resection, to minimize complications, and to reduce need for repeat surgery due to inadequate resection.

Fatty infiltration of the cervical extensor musculature, cervical sagittal balance, and clinical outcomes: An analysis of operative adult cervical deformity patients

PurposeTo assess preliminary associations between fatty-infiltration (FI) of cervical spine extensor musculature, cervical sagittal balance, and clinical outcomes in cervical deformity (CD) patients. MethodsOperative CD patients (C2-C7 Cobb > 10°, CL > 10°, cSVA > 4 cm, or CBVA > 25°) with pre-operative (BL) MRIs and 1-year (1Y) post-operative MRIs or CTs were assessed for fatty-infiltration of cervical extensor musculature, using dedicated imaging software at each C2-C7 intervertebral level and the apex of deformity (apex). FI was gauged as a ratio of fat-free-muscle-cross-sectional-area (FCSA) over total-muscle-CSA (TCSA), with lower ratio values indicating greater FI. BL-1Y associations between FI, sagittal alignment, and clinical outcomes were assessed using appropriate parametric and non-parametric tests. Results22 patients were included (Age 59.22, 71.4%F, BMI 29.2, CCI:0.75, Frailty: 0.43). BL deformity presentation: TS-CL: 29.0°, C2-C7 Sagittal Cobb:-1.6°, cSVA:30.4 mm. No correlations were observed between BL fatty-infiltration, sagittal alignment, frailty, or clinical outcomes (p > 0.05). Following surgical correction, C2-C7 (BL: 0.59 vs 1Y:0.67, p = 0.005) and apex (BL: 0.59 vs. 1Y: 0.66, p = 0.33) fatty-infiltration decreased. Achievement of lordotic curvature correlated with C2-C7 fatty infiltration reduction (Rs: 0.495, p < 0.05), and patients with residual postoperative TS-CL and cSVA malalignment were associated with greater apex fatty-infiltration (Rs: −0.565, −0.561; p < 0.05). C2-C7 FI improvement was associated with NRS back pain reduction (Rs: −0.630, p < 0.05), and greater apex fatty-infiltration at BL was associated with minor perioperative complication occurrence (Rs: 0.551, p = 0.014). ConclusionsDeformity correction and sagittal balance appear to influence the reestablishment of cervical muscle tone from C2-C7 and reduction of back pain for severely frail CD patients. This analysis helps to understand cervical extensor musculature’s role amongst CD patients.

Biplanar ascending opening-wedge high tibial osteotomy increases tibial tubercle–trochlear groove distance and decreases patellar height

ObjectivesTo assess the impact of a biplanar ascending opening-wedge high tibial osteotomy (OWHTO) on the alignment of the knee extensor mechanism and patellar height using preoperative and postoperative MRI.MethodsMedical records of all patients submitted to ascending biplanar OWHTO between July 2008 and March 2017 were retrospectively assessed. Five parameters of the patellofemoral joint—tibial tubercle–trochlear groove distance (TT-TG), patellofemoral (PF) axial engagement index, lateral patellar tilt, Blackburne-Peel index (BPI) and Caton-Deschamps index (CDI)—were measured by two blinded independent observers on both preoperative and postoperative MRIs. Interobserver reliability was assessed with the intraclass correlation coefficient (ICC). Paired t-test was performed to compare preoperative and postoperative measurements. The association of the amount of HTO opening and the assessed PF joint parameters was also investigated with Pearson correlation coefficient.Results26 patients who underwent ascending biplanar OWHTO were enrolled in this imaging analysis (63.4%) with a mean follow-up of 16.3 months (SD, 16.9). ICC for all measurements ranged between 73.3% and 89.3%. Postoperatively, TT-TG distance significantly increased by 2.0 mm±2.3 mm (p<0.001). Patellar height significantly decreased when evaluated by the BPI (p<0.001) and CDI (p=0.001). The amount of osteotomy opening significantly correlates with the postoperative BPI (p=0.023) and CDI (p=0.013).ConclusionThis study comprehensively reports significant increase on TT-TG distance after an ascending biplanar OWHTO using MRI. Small but significant decreases in patellar height were also observed and are correlated to the amount of axis correction.Level of evidenceLevel IV, retrospective case study.