Magnetic Resonance Imaging Reports Research Articles

Evaluating the Reliability Of MRI In Predicting The Degree Of ACL Tears In Pre-operative Planning For The Surgical Treatment Of ACL Tears: A Retrospective Study

Objectives: Anterior cruciate ligament (ACL) repair has regained interest in recent years as it has been demonstrated to provide favorable outcomes in patients with proximal ACL tears or avulsions. Magnetic resonance imaging (MRI) is the primary method uses to pre-operatively evaluate the ACL injury and help decide whether to perform an ACL repair or reconstruction. However, intraoperative findings often do not correspond with the MRI findings. This discrepancy may cause the surgeon to deviate from their initial surgical plan. Furthermore, some surgeons may disregard the possibility of performing an ACL repair solely due to the MRI report. Thus, potential candidates for ACL repair may be ignored due to the MRI report. This study aims to evaluate the reliability of MRI in predicting the degree of ACL tears planning for surgical treatment. Methods: We reviewed patients that underwent ACL repairs by a single surgeon at our institution between June 2015 to August 2018. All patients were initially seen for an ACL injury and were consulted for both ACL reconstruction and ACL repair. The final treatment decision was made following diagnostic arthroscopy. An ACL repair was performed only if the patient had a proximal tear, an intact but vertical ACL graft from a previous ACLR, or a tibial spine avulsion. Any patients that were missing MRI reports or operative reports were excluded. Pre-operative MRI of sagittal views of the ACL were then reviewed by a single radiologist and rated on integrity of the ligament’s midsubstance, and its tibial and femoral attachments. Intraoperative reports were then compared with the MRI reports. Results: We identified 40 consecutive ACL repairs of which 25 were included. Fifteen patients were excluded due to missing either operative or MRI reports. Of the included patients, 16 were males (64%) and the mean ± SD of age was 33.5±9.5 years (range 14-50 years). Two patients also had previous ACL reconstructions that failed and were subsequently revised with an ACL repair. MRIs demonstrated 15 full thickness tears with 9 torn at midsubstance, 2 torn at the tibial attachment, and 4 torn at the femoral attachment. Nine were reported as partial tears, with 4 torn at midsubstance, 2 torn at tibial attachment, and 3 torn at femoral attachment. One MRI reported no tear present. Intraoperatively, the surgeon identified 11 full-thickness tears, 11 partial tears, 2 tibial spine avulsions, and 2 incidences where a previous ACL reconstruction had failed due to a vertical graft. All of the full-thickness and partial tears were at the femoral attachment. The overall MRI sensitivity for the presence of an ACL injury was 96% with 2 false positives (8%), both of which revisions for failed ACLR. The overall accuracy was 32%, with specificity for tear-degree and tear-location 44% and 36%, respectively. Conclusion: Our results suggest that MRI may not be completely reliable in assessing the degree and location of an ACL tear. Furthermore, our results demonstrate that some patients who had repairable ACLs had MRI reports that suggested otherwise. Thus, our findings suggest that the surgeon should not solely rely on MRI imaging for ruling out possible ACL repair. This may also suggest that diagnostic tools, such as in-office diagnostic arthroscopy, be used in conjunction with MRI to more accurately assess the nature of an ACL tear. Future prospective studies with a larger sample size are necessary to confirm our findings that MRI may be less reliable for assessing ACL repair candidates.

MRI in the Follow-up of Testicular Cancer: Less is More.

This study aimed to report the location of abdominal relapse in patients with testicular cancer. This is a retrospective cross-sectional study including patients who underwent abdominal magnetic resonance imaging (MRI) after treatment of testicular germ cell cancer. MRI reports were classified as negative or positive, and positive results were cross-checked with follow-up imaging and biopsy results. Positive histology or cytology defined a true-positive finding. The location of relapse was registered according to the anatomical site. In a 2-year period, 2,315 MRI examinations were performed. Relapse was detected in 0.7% (95% CI=0.4-1.1) of the examinations. Among these, 75% were seminomas and 25% were non-seminomas. Retroperitoneal lymph nodes were affected in 88% of cases, and pelvic and inguinal lymph nodes affected in 12% of cases. No metastases were found in parenchymatous organs or bony structures. All cases of abdominal relapse occurred in retroperitoneal or pelvic lymph nodes. This suggests that MRI should be directed towards the retroperitoneum and pelvis only.

Magnetic Resonance Imaging Findings in Pediatric Pseudotumor Cerebri Syndrome

BackgroundRevised diagnostic criteria for pseudotumor cerebri syndrome require three of four neuroimaging findings in the absence of papilledema. We examined the sensitivity and specificity of three or more of four of these magnetic resonance imaging (MRI) findings for pseudotumor cerebri syndrome in children. MethodsAs part of clinical care, patients in whom there was suspicion for pseudotumor cerebri syndrome underwent neurological and fundoscopic examinations, lumbar puncture, MRI, or magnetic resonance venogram. For this retrospective study, we used this information to classify 119 subjects into definite (n = 66) or probable pseudotumor cerebri syndrome (n = 12), elevated opening pressure without papilledema (n = 23), or controls who had normal opening pressure without papilledema (n = 24). A neuroradiologist, unaware of the clinical findings or original MRI report, reviewed MRIs for pituitary gland flattening, flattening of the posterior sclera, optic nerve sheath distention, and transverse venous sinus stenosis. ResultsThe presence of three or more MRI findings has a sensitivity of 62% (95% confidence interval: 47% to 75%) and a specificity of 95% (95% confidence interval: 77% to 100%), compared with controls. Two of three (transverse venous sinus stenosis, pituitary gland flattening, flattening of the posterior sclera) had a similar sensitivity and specificity. Transverse venous sinus stenosis alone had a slightly higher sensitivity (74%, 95% confidence interval: 60% to 85%) and specificity (100%, 95% confidence interval: 80% to 100%). ConclusionsIn children, three of four of the proposed neuroimaging criteria and transverse venous sinus stenosis alone have a moderate sensitivity and robust specificity for pseudotumor cerebri syndrome. MRIs should be reviewed for these criteria, and their presence should raise suspicion for pseudotumor cerebri syndrome in children, particularly if the presence of papilledema is uncertain.

Radiologist and multidisciplinary team clinician opinions on the quality of MRI rectal cancer staging reports: how are we doing?

To evaluate the current opinion of magnetic resonance imaging (MRI) reports amongst specialist clinicians involved in colorectal cancer multidisciplinary teams (CRC MDTs). Active participants at 16 UK CRC MDTs across a population of 5.7 million were invited to complete a questionnaire, this included 22 closed and three open questions. Closed questions used ordinal (Likert) scales to judge the subjective inclusion of tumour descriptors and impressions on the clarity and consistency of the MRI report. Open (free-text) questions allowed overall feedback and suggestions. A total of 69 participants completed the survey (21 radiologists and 48 other CRC MDT clinicians). Both groups highlighted that reports commonly omit the status of the circumferential resection margin (CRM; 83% versus 81% inclusion, other clinicians and radiologists, respectively, p>0.05), presence or absence of extra-mural venous invasion (EMVI; 67% versus 57% inclusion, p>0.05), and lymph node status (90% inclusion in both groups). Intra-radiologist agreement across MRI examinations is reported as 75% by other clinicians. Free-text comments included suggestions for template-style reports. Both groups recognise a proportion of MRI reports are suboptimal with key tumour descriptors omitted. There are also concerns around the presentation style of MRI reports and inter- and intra-radiologist report variability. The widespread implementation of standardised report templates may improve completeness and clarity of MRI reports for rectal cancer and thus clinical management and outcomes in rectal cancer.

Longitudinal Visualization of Viable Cancer Cell Intratumoral Distribution in Mouse Models Using Oatp1a1-Enhanced Magnetic Resonance Imaging.

Multimodality reporter gene imaging provides valuable, noninvasive information on the fate of engineered cell populations. To complement magnetic resonance imaging (MRI) measures of tumor volume and 2-dimensional reporter-based optical measures of cell viability, reporter-based MRI may offer 3-dimensional information on the distribution of viable cancer cells in deep tissues. Here, we engineered human and murine triple-negative breast cancer cells with lentivirus encoding tdTomato and firefly luciferase for fluorescence imaging and bioluminescence imaging (BLI). A subset of these cells was additionally engineered with lentivirus encoding organic anion transporting polypeptide 1a1 (Oatp1a1) for MRI. Oatp1a1 operates by transporting gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) into cells, and it concomitantly improves BLI substrate uptake. After orthotopic implantation of engineered cells expressing or not expressing Oatp1a1, longitudinal fluorescence imaging, BLI, and 3-Tesla MRI were performed. Oatp1a1-expressing tumors displayed significantly increased BLI signals relative to control tumors at all time points (P < 0.05). On MRI, post-Gd-EOB-DTPA T1-weighted images of Oatp1a1-expressing tumors exhibited significantly increased contrast-to-noise ratios compared with control tumors and precontrast images (P < 0.05). At endpoint, tumors expressing Oatp1a1 displayed intratumoral MR signal heterogeneity not present at earlier time points. Pixel-based analysis of matched in vivo MR and ex vivo fluorescence microscopy images revealed a strong, positive correlation between MR intensity and tdTomato intensity for Oatp1a1-expressing tumors (P < 0.05), but not control tumors. These results characterize Oatp1a1 as a sensitive, quantitative, positive contrast MRI reporter gene for 3-dimensional assessment of viable cancer cell intratumoral distribution and concomitant BLI enhancement. This multimodality reporter gene system can provide new insights into the influence of viable cancer cell intratumoral distribution on tumor progression and metastasis, as well as improved assessments of anticancer therapies.

Feasibility of point-of-care knee ultrasonography for diagnosing anterior cruciate and posterior cruciate ligament tears in the ED

ObjectiveTo evaluate the feasibility of point-of-care knee ultrasonography (POCUS) compared with knee magnetic resonance imaging (MRI) for diagnosing anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) tears in patients with acute knee trauma. Material and methodsA prospective study was conducted in a tertiary hospital emergency department; acute (within 1-week) knee trauma patients with suspected ACL or PCL tear were recruited. Two POCUS performers (a board-certified emergency physician and a musculoskeletal radiologist) independently evaluated the ACL and PCL using POCUS. Findings were classified as normal appearance or ligament tear. Final radiology reports of knee MRI were used as the reference standard. We calculated the diagnostic values (sensitivity, specificity, and accuracy) for POCUS obtained by both POCUS performers. Kappa values (k) were calculated for inter-observer agreement between the two POCUS performers. ResultsSixty-two patients were enrolled. Compared with the reference standard, POCUS showed acceptable sensitivity (90.6–100%), specificity (90.0–97.7%), and accuracy (91.9–96.8%). Inter-observer agreement between the two POCUS performers was excellent (k = 0.853–0.903). ConclusionPOCUS demonstrates excellent precision as compared to MRI in the diagnosis of ACL and PCL tears. The findings of POCUS could be used for immediate diagnosis and further pre-operative imaging in patients with acute knee trauma.

Impact of pelvic MRI in routine clinical practice on staging of IB1-IIA2 cervical cancer.

Purpose: To evaluate the impact of pelvic magnetic resonance imaging (MRI) on staging of IB1–IIA2 cervical cancer in routine clinical practice.Patients and Methods: A total of 1,016 patients with IB1-IIA2 cervical cancer who underwent primary surgery and preoperative pelvic MRI between January 2009 and December 2015 were identified in a retrospective multicentre study. Data on clinical stage, MRI reports and surgicopathologic findings were extracted from medical records. The impact of MRI on clinical staging was evaluated by comparison before and after combination of MRI. Using surgicopathologic findings as the reference standard, the impact of pelvic MRI on the accuracy of clinical staging was evaluated. Furthermore, the impact on the accuracy of individual staging parameters such as maximal tumor diameter, vaginal involvement or parametrial infiltration were also evaluated.Results: After combination of pelvic MRI, clinical stage remained unchanged in 59.7%, upstaged in 17.2%, and downstaged in 23.0% of the patients. The overall accuracy of clinical staging increased from 61.0% to 81.4% in our study (P<0.05). As for individual staging parameters, the area under the curve (AUC) for maximal tumor diameter increased from 0.58 to 0.81 (P<0.05). However, the AUC for vaginal involvement decreased from 0.61 to 0.57 (P>0.05). The AUC for parametrial infiltration was also suboptimal (AUC=0.56, P<0.05).Conclusion: In routine clinical practice, MRI could increase the overall accuracy of clinical staging in IB1–IIA2 cervical cancer. For staging parameters, it only significantly increased the accuracy of maximal tumor diameter.

Structured reports of pelvic magnetic resonance imaging in primary endometrial cancer: Potential benefits for clinical decision-making.

BackgroundAlthough evidence is increasing that the implementation of structured reports (SRs) may increase the standardization of reports and improve communication between radiologists and end-users, it is unclear whether these alternative formats of Chinese radiological narratives are appealing or even acceptable to radiologists and clinicians.ObjectiveTo compare the effect of SRs and non-structured reports (NSRs) of pelvic magnetic resonance imaging (MRI) in patients with primary endometrial cancer on referring gynecologists’ satisfaction, further decision-making and efficiency.MethodsForty-one patients with histologically proven endometrial cancer were included in this study. SRs and NSRs for local MRI staging of endometrial cancer were generated for all subjects. NSRs were generated during clinical routine practice. The same 41 uterine studies were reviewed by the same radiologist using structured reporting system after a period of time. Two radiologists compared SRs on the number of key features related to cancer staging and writing efficiency with NSRs together. Five gynecologists filled in questionnaires regarding satisfaction with content, clinical usefulness, report’ quality and time consumption. Statistical analysis included Kendall’s W test, paired-sample t test and Wilcoxon signed rank test.ResultsThere was no significant difference in the number of key features in NSRs comparison to SRs (p = 0.055). A statistically significant difference was observed in the satisfaction with linguistic quality for NSRs versus SRs by three gynaecologists (reader 1: 4.02 vs. 4.63, p = 0.002; reader 3: 3.86 vs. 4.02, p = 0.035; reader 4: 4.05 vs. 4.27, p = 0.024). The radiologist spent less time finishing SRs compared with NSRs (727.22 ± 38.42 sec vs. 616.44 ± 60.00 sec, p = 0.037).ConclusionsThe application of SRs significantly increased the value of female pelvic MRI reports by increasing radiologists’ work efficiency and gynaecologists' satisfaction.

Prevalence of extramedullary hematopoiesis, renal cysts, splenic and hepatic lesions, and vertebral hemangiomas among thalassemic patients: a retrospective study from the Myocardial Iron Overloadin Thalassemia (MIOT) network.

We determined the prevalence of incidental extracardiac findings (IEF) at Magnetic Resonance Imaging (MRI) potentially related to anemia and hypoxia in age- and sex-matched populations (N = 318) with thalassemia major (TM) and thalassemia intermedia (TI) enrolled in the Myocardial Iron Overload in Thalassemia network. Overall, IEFs were detected in 33.3% and 25.8% of patients with TI and TM, respectively (P = 0.114). TI and TM patients had elevated but comparable prevalence of renal, splenic and liver cysts, and vertebral hemangiomas while TI patients had a significant higher frequency of extramedullary hematopoiesis (EMH) (15.1% vs 4.4%; P = 0.002). The prevalence of total IEFs increased with advancing age. TI non-transfusion-dependent patients had a significantly lower frequency of renal cysts than TI transfusion-dependent patients (8.8% vs 26.4%; P = 0.005). The prevalence of renal cysts in the thalassemic population was significantly higher than that in the general population (19.2% vs 1.9%; P < 0.0001). Our data on renal cysts indicate a significant higher prevalence of these IEFs compared to the general population, suggesting the role of the inappropriate activation of the hypoxia-inducible factor system linked to the chronic hypoxia. The significant prevalence of IEF in thalassemia patients undergoing MRI for iron quantification should prompt the discussion of the inclusion of IEF in the MRI report.

Is routine MRI of the spine necessary in trauma patients with ankylosing spinal disorders or is a CT scan sufficient?

BackgroundAnkylosing spinal disorder (ASD) patients are at a greater risk for spinal fractures due to osteoporosis and rigidity of the spinal column. These fractures are associated with a high risk of neurologic compromise resulting from delayed or missed diagnoses. Although computed tomography (CT) is usually the initial imaging modality, magnetic resonance imaging (MRI) has been proposed as mandatory to help identify spinal injuries in ASD patients with unexplained neck or back pain or known injuries to help identify noncontiguous fractures. However, some studies have also shown that neurological injury can result from the required patient transfer and positioning for an MRI. PurposeThe purpose of our study was to assess the frequency with which an MRI identified an injury not previously identified with CT, and whether this affected the treatment and outcome of the patient. Secondarily, we attempted to identify clinical or CT findings that may render an MRI particularly useful. Study DesignRetrospective review. Patient SamplePatients with ASD who sustained acute spine fractures from 2005 to 2015. Outcome MeasuresAcute fractures identified by CT scan and MRI upon admission; neurologic status upon admission and discharge, mode of injury, type of fracture, and final intervention before and after MRI assessment. MethodsA total of 124 patients with a diagnosis of diffuse idiopathic skeletal hyperostosis (DISH) or ankylosing spondylitis (AS) were identified by searching the radiology database of a level I trauma center with diagnosis keywords. Final radiology reports were assessed to determine presence and type of fracture(s) from CT. MRI report was then reviewed to assess if additional fractures or injuries were identified beyond that already known from the CT. Neurologic status upon admission and discharge, mode of injury, type of fracture, and final intervention were determined by inpatient notes and/or operative reports. No source funding or conflict of interest was present pertaining to this study. ResultsIn the designated time frame, 124 ASD patients with injuries of the spine were identified who had obtained both a baseline CT and MRI. Six patients (4.8%) had additional injuries on MRI that had not been identified with CT. Four of these six patients had a change in treatment plan (three operative and one nonoperative) based on subsequent MRI findings. These included a (1) C4–5 hyperextension injury, (2) C6–7 hyperextension injury, (3) C7 bony fracture with C5–T4 epidural hematoma, and (4) C5–C6 hyperextension injury treated in a brace. Two of the six patients that had additional injuries identified on MRI had no change in their treatment plan. One patient had an additional lumbar extension injury identified above a previously diagnosed injury on CT, which was managed with a Thoracolumbosacral Orthosis (TLSO) according to the original plan. One patient died who had a known odontoid fracture and a suspected C6–7 hyperextension injury, and was identified on MRI as also having a C3–C4 hyperextension injury and a C2 spinal cord transection. ConclusionsIn this study, 3.2% (4/124) of patients with ASD who presented to a level I trauma center with an acute spine injury identified with CT required a change in their treatment plan based on subsequent MRI findings. Only one fracture was missed on CT imaging, with the other missed injuries all being either disco-ligamentous hyperextension injuries through mobile discs or intracanal pathology. Our recommendation is that the routine use of MRI be limited to patients with nonankylosed levels in which a disco-ligamentous injury may have occurred, and in patients with neurological deficits that require investigation of the spinal canal to assess for causes of neurological injury.

A proposal for standardized magnetic resonance imaging (MRI) descriptors of abnormally invasive placenta (AIP)-From the International Society for AIP.

Abnormally invasive placenta (AIP) is used to describe a placenta that does not separate naturally after delivery and cannot be extirpated without causing abnormally high blood loss. Recently, the use of a standardized terminology for descriptors of AIP signs seen on ultrasound has been prosed but to date no such unified descriptors have been developed for magnetic resonance imaging (MRI). The purpose of this paper is to propose a unified terminology based on a consensus opinion from the members of the International Society for AIP (IS-AIP) that include obstetricians, gynecologists, radiologists, pathologists, anesthesiologists and basic science researchers. We assume that using these standardized MRI descriptors for AIP will be useful for clinical use, education, teaching and future research projects, thus assumably improving care of patients with this condition. In addition, using a uniform terminology for AIP should become the first step of a standardized MRI report.

Standardised reports with a template format are superior to free text reports: the case for rectal cancer reporting in clinical practice

PurposeRectal cancer staging with magnetic resonance imaging (MRI) allows accurate assessment and preoperative staging of rectal cancers. Therefore, complete MRI reports are vital to treatment planning. Significant variability may exist in their content and completeness. Template-style reporting can improve reporting standards, but its use is not widespread. Given the implications for treatment, we have evaluated current clinical practice amongst specialist gastrointestinal (GI) radiologists to measure the quality of rectal cancer staging MRI reports.Materials and methodsSixteen United Kingdom (UK) colorectal cancer multi-disciplinary teams (CRC-MDTs) serving a population over 5 million were invited to submit up to 10 consecutive rectal cancer primary staging MRI reports from January 2016 for each radiologist participating in the CRC-MDT. Reports were compared to a reference standard based on recognised staging and prognostic factors influencing case managementResultsFour hundred ten primary staging reports were submitted from 41 of 42 (97.6%) eligible radiologists. Three hundred sixty reports met the inclusion criteria, of these, 81 (22.5%) used a template. Template report usage significantly increased recording of key data points versus non-template reports for extra-mural venous invasion (EMVI) status (98.8% v 51.6%, p < 0.01) and circumferential resection margin (CRM) status (96.3% v 65.9%, p < 0.01). Local tumour stage (97.5% v 93.5%, NS) and nodal status (98.8% v 96.1%, NS) were reported and with similar frequency.ConclusionRectal cancer primary staging reports do not meet published standards. Template-style reports have significant increases in the inclusion of key tumour descriptors. This study provides further support for their use to improve reporting standards and outcomes in rectal cancer.Key Points• MRI primary staging of rectal cancer requires detailed tumour descriptions as these alter the neoadjuvant and surgical treatments.• Currently, rectal cancer MRI reports in clinical practice do not provide sufficient detail on these tumour descriptors.• The use of template-style reports for primary staging of rectal cancer significantly improves report quality compared to free-text reports.

Abstract P1-15-15: Accuracy of MRI after neoadjuvant therapy for invasive lobular carcinoma of the breast

Abstract Background: Invasive lobular carcinoma of the breast (ILC) has higher rates of false negative imaging than invasive ductal carcinoma, and lower rates of neoadjuvant therapy (NAT) use. We evaluated the accuracy of Breast Imaging Reporting And Data System (BIRADS) findings on magnetic resonance imaging (MRI) after either neoadjuvant chemotherapy or endocrine therapy, and determined whether imaging change correlates with disease free survival. Methods: We queried a database of 674 ILC cases treated at UCSF from 1981-2017 and identified all patients treated with NAT. We reviewed MRI reports and recorded BIRADS descriptors of findings, maximal tumor diameter for mass or non-mass enhancement (NME), and subjective radiologist comments on progression or improvement. We used the t-test, chi-squared test, Pearson's correlation, and Kaplan Meier survival estimates to evaluate the accuracy of MRI after NAT compared to true tumor size on pathology, and the relationship between imaging change and disease free interval in Stata 14.2. Results: Of 136 patients with ILC treated with NAT, we included 101 women who had a post-treatment breast MRI report available. Of these, 58.4% received neoadjuvant chemotherapy, and 41.6% neoadjuvant endocrine therapy. After NAT, MRI findings were mass only in 43%, both mass/NME in 33%, NME only in 18%, and neither in 5%. Maximal diameter of mass on post-treatment MRI underestimated true size by a mean of 3.3 cm (range -3.6 to 15.3 cm). NME size on post-treatment MRI underestimated true size by a mean of 1.87 cm (range -7.2 to 9.7 cm). Mass size on MRI underestimated true size by ≥1 cm in 61.5% of cases; this size discrepancy was associated with increased positive margins (46.4% versus 20%, p=0.011). NME size on MRI underestimated true size by at ≥1 cm in 65.6%. The correlation coefficient between mass size on MRI and true size was 0.34 (p=0.0041), which increased to 0.67 (p&amp;lt;0.0001) when excluding those with associated NME. The correlation coefficient between NME size on MRI and true size was 0.28 (p=0.1239). Subjective progression on post-treatment MRI was associated with increased recurrence rates (80% versus 18.3%, p=0.001). In those with subjective improvement on MRI, there was a trend towards longer disease free interval (89% versus 73% disease free at 4 years, p=0.13). Table 1.Patient and tumor characteristics. Neoadjuvant chemotherapy (n=59)Neoadjuvant endocrine therapy (n=42)P valueMean age (yrs, 95% CI)53.6 (50.9-56.3)61.3 (58.4-64.1)0.0002Subtype 0.105ER+ PR+ HER2-29 (53.7%)23 (62.16%) ER+ PR- HER2-14 (25.9%)13 (35.14%) ER- PR- HER2-1 (1.85%)0 HER2+10 (18.5%)1 (2.7%) Grade 0.076114 (25%)16 (38.1%) 237 (66.1%)26 (61.9%) 35 (8.93%)0 Surgical stage &amp;lt;0.001I17 (28.81%)28 (66.67%) II26 (44.07%)6 (14.29%) III16 (27.12%)8 (19.1%) Mean follow-up time (yrs, 95% CI)5.6 (4.53-6.75)5.1 (3.84-6.27)0.48 Conclusions: Maximal tumor diameter on MRI after NAT in ILC vastly underestimates true tumor size. While these findings suggest using caution when using an MRI for surgical planning in patients with ILC, particularly if there is associated NME, the trend towards improved disease free survival in those with a subjective improvement is intriguing and suggests that MRI changes could become an early predictor of outcomes. Citation Format: Fahrner-Scott KE, Wong JM, Piper M, Ewing C, Alvarado M, Esserman LJ, Hylton N, Mukhtar RA. Accuracy of MRI after neoadjuvant therapy for invasive lobular carcinoma of the breast [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-15-15.

Primary diagnosis of pulmonary embolism with unenhanced MRI for patients not eligible for CTPA: Clinical outcome

PurposeTo follow up the clinical outcome of patients with suspected pulmonary embolism (PE), in those only imaged using unenhanced, free-breathing magnetic resonance imaging (MRI). Methods and materialsFifty-seven patients aged 29–99 years (mean 70, SD 18) that could not undergo Computed Tomography Pulmonary Angiography (CTPA) were offered alternative imaging diagnostics in parallel with ongoing methodological studies validating MRI vs CTPA. Contraindications included renal failure (n = 44), severe iodine contrast allergy (n = 10), pregnancy (n = 2) and radioactive iodine therapy (n = 1). The unenhanced MRI protocol was based on free-breathing, steady-state free precession with no cardiac or respiratory gating. Retrospective review of the electronic medical record (EMR) was made of 0–12 months post-imaging and was collected during 2012–2018. ResultsAll 57 MRIs were of diagnostic quality and 12 pulmonary embolisms were diagnosed. Of the 57 patients, 44 were already on, or had started anticoagulation therapy due to clinical suspicion of PE. Four of the patients were put on anticoagulation after the positive MRI and 13 were taken off anticoagulation after a negative MRI report. Other diagnoses reported (considering dyspnea) were pleural effusion (n = 24), consolidation (n = 12) and pericardial effusion (n = 2). One patient had a deep vein thrombosis (DVT) within three months of our negative MRI result and then had a stroke within one year. Another patient suffered a stroke within three months of being diagnosed (by MRI) with PE and given anticoagulation as treatment. ConclusionsOur method supported or altered clinical decision-making and treatment in this cohort. A diagnostic tool for PE without intravenous contrast agent or radiation is of great benefit for certain patients.

Incidence of Intraspinal and Extraspinal MRI Abnormalities in Patients With Adolescent Idiopathic Scoliosis

Study DesignRetrospective study with follow-up. ObjectivesThe purpose of this study was to determine the incidence of intraspinal and extraspinal MRI abnormalities in a consecutive series of patients with adolescent idiopathic scoliosis (AIS) and to describe the evaluation and management of these abnormalities. Summary of Background DataIndications for preoperative magnetic resonance imaging (MRI) in patients with AIS remain controversial. Previous studies have reported a wide range of abnormality rates; however, the majority of these studies focus on a nonconsecutive series of patients, and none of these studies report the incidence of extraspinal abnormalities. MethodsWe studied a consecutive series of patients with AIS managed with spinal deformity surgery. All patients underwent a routine neural axis MRI prior to surgery. MRI reports were reviewed, and intraspinal and extraspinal abnormalities were recorded. Additional chart review and follow-up was performed to determine the rates of evaluation and management for these abnormalities. Descriptive statistics were used to describe the incidence and types of abnormalities, as well as the rates of evaluation and management. ResultsThis study included a consecutive series of 259 patients with AIS. MRI abnormalities were noted in 115 patients (44%). After excluding patients with degenerative changes, MRI abnormalities were noted in 64 patients (25%). The incidence of Chiari malformation was 4.2% and syringomyelia was 5%. Extraspinal abnormalities were noted in 10% of patients, and these findings ranged from benign cysts to malignant soft tissue tumor. Approximately 10% of patients needed additional evaluation because of their preoperative MRI findings, and 0.7% of patients required surgical management prior to spinal deformity surgery. ConclusionsSignificant MRI abnormalities were noted in patients with AIS, and some patients required further evaluation prior to surgery. Additional study including cost-effectiveness analysis is needed to better define the role of preoperative MRI in patients with AIS. Level of EvidenceLevel II.

Preoperative Assessment of the Peroneal Tendons in Lateral Ankle Instability: Examining Clinical Factors, Magnetic Resonance Imaging Sensitivity, and Their Relationship

The purpose of our study was to examine the preoperative clinical factors and magnetic resonance imaging (MRI) findings associated with peroneal pathology in chronic lateral ankle instability patients, as well as the clinical factors associated with peroneal lesions being detected on MRI. Peroneal pathology was determined from intraoperative findings. Patients with/without peroneal pathology were compared regarding their preoperative clinical findings. MRI reports were examined to determine the sensitivity of detecting peroneal pathologies. Clinical factors were compared between patients (N = 238) with undetected and detected peroneal lesions on MRI. Conservative treatment, preoperative physical therapy, and lack of a traumatic inciting event were associated with peroneal pathology. MRI had a sensitivity of 61.11% for detecting peroneal pathology. No clinical factors were significantly different between “detected” and “undetected” cases. Certain historical factors were associated with peroneal pathology in patients with chronic lateral ankle instability, and MRI had a high false-negative rate. Surgeons should exercise caution when ruling out peroneal pathology based on preoperative physical examination or MRI.

An audit of performance, interpretation, and influence of pretherapeutic MRI in rectal cancer: a Swedish population-based cohort study.

Background The performance of magnetic resonance imaging (MRI) interpretation and communication of findings and its implication on treatment decisions has not fully been explored in rectal cancer. Purpose To investigate in a region the adherence to MRI protocol standards and the relation between MRI interpretation and selection to preoperative therapy in rectal cancer. Material and Methods Data on consecutive patients who underwent elective rectal cancer surgery in the region from January to June 2010 were obtained from the National Colorectal Cancer Registry. Pretherapeutic MRI images were re-evaluated. Agreement between the original reports and the re-evaluation was compared using Cohen’s kappa coefficient. Results Among the 94 patients included, 81 (86%) had pretherapeutic MRI in accordance with defined imaging guidelines. In 34% of the original MR reports, data on extramural venous invasion (mrEMVI) and mrT category were not reported. Complete tumor staging was not possible because of missing data in 33 (35%) of the patients. The agreement between the original MR reports and the re-evaluation regarding tumor stage was moderate (κ = 0.48). For decided treatment compared to recommended preoperative treatment according to the re-evaluation, the agreement was fair (κ = 0.33). Conclusion Established MRI protocol standards were not universally applied. Missing data and inadequacies in original MRI reports resulted in moderate agreement between the original report and the re-evaluation indicating a risk of inappropriate treatment selection. The results call for further educational efforts in rectal cancer MRI acquisition and repeated audits of image protocol adherence and interpretation quality.

Sensitivity of orbital magnetic resonance imaging in acute demyelinating optic neuritis

ObjectiveTo determine the sensitivity of orbital magnetic resonance imaging (MRI) in acute demyelinating optic neuritis (ON) in routine clinical practice, and the added value of a dedicated neuroradiology interpretation. DesignRetrospective chart review. ParticipantsPatients with clinically proven ON evaluated between 2004 and 2014 in the University of Michigan neuro-ophthalmology clinics. Inclusion criteria involved visual recovery and orbital MRI completed within 30days of symptom onset and before corticosteroid treatment. MethodsDemographics, clinical examination, and MRI report data (high T2 signal, gadolinium contrast enhancement) were abstracted for each eligible eye. Every MRI was reinterpreted by a neuroradiologist masked to the affected side. Descriptive statistics summarized patient and eye characteristics. Interrater agreement between the neuroradiologist and the radiology report for the radiographic diagnosis of ON was assessed with Cohen's kappa statistic. ResultsOf 92 patients who met all inclusion criteria, 70 (76.1%) were reported to have at least 1 MRI feature consistent with ON. After dedicated review by a neuroradiologist, 77 (83.7%) were determined to have a positive MRI for ON. Agreement between the neuroradiologist and MRI report was moderate (κ = 0.63). Gadolinium enhancement was the most common feature in MRI positive ON (72 [78.3%] of neuroradiology reviewed MRIs; 66 [71.7%] of clinical MRI reports). ConclusionsThe sensitivity of MRI in ON was lower than previously reported and confirms the importance of making a clinical diagnosis of ON without relying on neuroimaging for confirmation. MRI interpretation by a skilled neuroradiologist increased sensitivity, underscoring the complexity of orbital MRI interpretation.

In Vitro Neural Differentiation of Bone Marrow Mesenchymal Stem Cells Carrying the FTH1 Reporter Gene and Detection with MRI.

Magnetic resonance imaging (MRI) based on the ferritin heavy chain 1 (FTH1) reporter gene has been used to trace stem cells. However, whether FTH1 expression is affected by stem cell differentiation or whether cell differentiation is affected by reporter gene expression remains unclear. Here, we explore the relationship between FTH1 expression and neural differentiation in the differentiation of mesenchymal stem cells (MSCs) carrying FTH1 into neuron-like cells and investigate the feasibility of using FTH1 as an MRI reporter gene to detect neurally differentiated cells. By inducing cell differentiation with all-trans retinoic acid and a modified neuronal medium, MSCs and MSCs-FTH1 were successfully differentiated into neuron-like cells (Neurons and Neurons-FTH1), and the neural differentiation rates were (91.56±7.89)% and (92.23±7.64)%, respectively. Neuron-specific markers, including nestin, neuron-specific enolase, and microtubule-associated protein-2, were significantly expressed in Neurons-FTH1 and Neurons without noticeable differences. On the other hand, FTH1 was significantly expressed in MSCs-FTH1 and Neurons-FTH1 cells, and the expression levels were not significantly different. The R2 value was significantly increased in MSCs-FTH1 and Neurons-FTH1 cells, which was consistent with the findings of Prussian blue staining, transmission electron microscopy, and intracellular iron measurements. These results suggest that FTH1 gene expression did not affect MSC differentiation into neurons and was not affected by neural differentiation. Thus, MRI reporter gene imaging based on FTH1 can be used for the detection of neurally differentiated cells from MSCs.

P.015 Mesial Temporal Sclerosis is a rare occurrence in Intractable Pediatric Temporal Lobe Epilepsies

Background: Temporal lobe epilepsy (TLE) accounts for approximately 20% of pediatric epilepsy cases. Of those, many are considered medically intractable and require surgical interventions. In this study, we hypothesized that mesial temporal sclerosis (MTS) was less common in patients who had undergone surgery for intractable pediatric TLE than in adult series. We further hypothesized that there was a radiological and pathological discordance in identifying the cause of pediatric TLE. Methods: We retrospectively reviewed the charts of pediatric patients with TLE who had undergone surgical treatments as part of the University of Alberta’s Comprehensive Epilepsy Program between 1988 and 2018. Along with preoperative magnetic resonance imaging (MRI) reports, post-surgical pathology results and seizure outcomes were studied Results: Of the 83 pediatric patients who had undergone temporal lobe epilepsy surgery, 28% had tumors, 22% had dual pathologies, 18% had MTS, 11% had focal cortical dysplasia, and 22% had other pathologies. In addition, for 36% of these patients, discordance between their pre-surgical MRI reports and post-surgical pathology reports were found. Conclusions: This was one of the largest retrospective cohort studies of pediatric patients who had undergone surgery for intractable TLE. This study showed that tumors, and not MTS, were the most common pathology in surgical pediatric TLE.