Preoperative Magnetic Resonance Imaging Assessment Research Articles

Preoperative CT and MRI assessment of the longitudinal tumor extent of extrahepatic bile duct cancer after biliary drainage

To examine the diagnostic performance for the longitudinal extent of extrahepatic bile duct (EHD) cancer on computed tomography (CT) after biliary drainage (BD) and investigate the appropriate timing of magnetic resonance imaging (MRI) acquisition. This retrospective study included patients who underwent curative-intent surgery for EHD cancer and CT pre- and post-BD between November 2005 and June 2021. The biliary segment-wise longitudinal tumor extent was evaluated according to the 2019 Korean Society of Abdominal Radiology consensus recommendations, with pre-BD CT, post-BD CT, and both pre- and post-BD CT. The performance for tumor detectability was compared using generalized estimating equation (GEE) method. When preoperative MRI was performed, patients were divided into two subgroups according to the timing of MRI with respect to BD, and the performance of MRI obtained pre- and post-BD was compared. In 105 patients (mean age: 67 ± 8 years; 74 men and 31 women), the performance for tumor detectability was superior using both CT scans compared with using post-BD CT alone (reader 1: sensitivity, 72.6% vs. 64.6%, P < 0.001; specificity, 96.9% vs. 94.8%, P = 0.063; reader 2: sensitivity, 77.2% vs. 72.9%, P = 0.126; specificity, 97.5% vs. 94.2%, P = 0.003), and it was comparable with using pre-BD CT alone. In biliary segments with a catheter, higher sensitivity and specificity were observed using both CT scans than using post-BD CT (reader 1: sensitivity, 74.4% vs. 67.5%, P = 0.006; specificity, 92.4% vs. 88.0%, P = 0.068; reader 2: sensitivity, 80.5% vs. 74.4%, P = 0.013; specificity, 94.3% vs. 88.0%, P = 0.016). Post-BD MRI (n = 30) exhibited a comparable performance to pre-BD MRI (n = 55) (reader 1: sensitivity, 77.9% vs. 75.0%, P = 0.605; specificity, 97.2% vs. 94.9%, P = 0.256; reader 2: sensitivity, 73.2% vs. 72.6%, P = 0.926; specificity, 98.4% vs. 94.9%, P = 0.068). Pre-BD CT provided better diagnostic performance in the preoperative evaluation of EHD cancer. The longitudinal tumor extent could be accurately assessed with post-BD MRI, which was similar to pre-BD MRI. The acquisition of pre-BD CT could be beneficial for the preoperative evaluation of EHD cancer when BD is planned. Post-BD MRI would not be significantly affected by BD in terms of the diagnostic performance of the longitudinal tumor extent.

Predictive value of preoperative MRI using the #ENZIAN classification score in patients with deep infiltrating endometriosis.

The aim of this study is to investigate the correlation between the magnetic resonance imaging (MRI) and intraoperative findings of deep infiltrating endometriosis using the #ENZIAN score. This retrospective study included 64 patients who underwent surgery for deep infiltrating endometriosis between January 2017 and August 2020. Preoperative abdominopelvic MRI assessment was evaluated and scored using the #ENZIAN classification. Operative scores were considered the gold standard, and the sensitivity, specificity, and positive and negative predictive values (PPV and NPV) of MRI for each category were calculated. MRI has higher sensitivity and specificity in showing the lesions of the compartments O (ovarian lesions), A (rectovaginal septum and posterior vaginal fornix), and B (uterosacral ligaments and parametrium) (100-100%, 100-100%, and 97-100%, respectively, p < 0.001) compared to the other compartments. The lowest sensitivity, specificity, accuracy, and PPV of the MRI was found in compartment P (14%, 76%, 70%, and 7%, respectively). We demonstrated that the #ENZIAN classification in MRI reports has significant sensitivity and specificity in compartments A, B (uterosacral ligaments and parametrium), and O. Furthermore, the determination of peritoneal lesions via MRI is inadequate.

Does magnetic resonance imaging impact pre-operative plans in adolescent idiopathic scoliosis patients? A retrospective study

Objectives: Adolescent idiopathic scoliosis (AIS) has been rigorously discussed in academia for the better part of a century, primarily due to its nuanced and complex management. To date, there are no universal criteria for its management. The use of pre-operative magnetic resonance imaging (MRI) in all patients with AIS is still debatable. We aimed to determine the necessity of using pre-operative routine MRI assessment in all patients treated for AIS. Methods: A retrospective and descriptive medical chart review study was done. We examined AIS patients diagnosed between 10 and 18 years of age who underwent surgical treatment between 2016 and 2020. A full medical history and a complete spine clinical examination were performed on all patients. Results: Of 267 consecutive patients with verified AIS who underwent surgical correction, 176 were included in the analysis. All patients had normal pre-operative physical and neurological examinations. There were 138 (78%) female and 38 (22%) male patients. MRI findings of neural axis abnormalities were observed in eight of 176 patients (4.54%). Conclusion: In our study, the incidence of abnormalities in the neural axis was low and no additional neurosurgical procedures were performed. This could be due to our strict inclusion criteria. However, we cannot establish a recommendation regarding the routine use of pre-operative MRI. A meta-analysis of the currently available data may provide a better assessment in terms of cost-effectiveness and pave the way for the implementation of guidelines for screening protocols.

Hill-Sachs Remplissage Procedure and its Role in Arthroscopic Stabilisation of the Shoulder

The arthroscopic Hill-Sachs Remplissage procedure was first described in 2004 and published in 2008. It consists of an arthroscopic posterior capsulodesis combined with an infraspinatus tenodesis to achieve a “filling in” effect of posterior humeral head defects. The technique was put forward as a solution to high rates of Bankart repair failure, in the presence of large Hill-Sachs lesions. We describe the evolution of the technique and its outcomes and report on the evolving surgical indications over the last decade in response to new paradigm shifts. Due to a better understanding of the pathophysiology of shoulder instability, emphasis was given to both Bankart soft tissue repair and to the associated bony injuries, accounting for both glenoid and humeral head (bipolar) bone loss. We present the transition from the concept of “engaging” Hill-Sachs lesions to the concept of “on-track” / “off-track” lesions and the current role of Remplissage in shoulder instability surgery which remains paramount. We believe that in view of the critical role of bipolar bone defects in shoulder instability, preoperative magnetic resonance imaging assessment of the glenoid track of Hill-Sachs lesions is becoming increasingly important in preoperative planning. This allows the orthopaedic surgeon to detect an “off-track” lesion, select the appropriate surgical technique and improve surgical outcomes.

Predictors of invasive disease in patients preoperatively diagnosed with ductal carcinoma without stromal invasion, with breast magnetic resonance imaging (MRI) and ultrasound (US).

A preoperative diagnosis of ductal carcinoma in situ (DCIS) is sometimes upstaged to invasive disease postoperatively. Our objective was to clarify the predictive factors of invasive disease using preoperative imaging and to investigate the positive ratio of sentinel lymph nodes (SLN) and the incidence of invasive disease. The subjects were 402 patients with preoperatively diagnosed ductal carcinoma without stromal invasion who underwent breast surgery with concomitant SLN surgery in January 2007 to December 2016. Of the 306 included patients, all 306 patients underwent preoperative MRI and US assessment. Outcomes were analyzed for significance using univariate and multivariate analyses. Of the 306 patients, 115 (37.6%) had invasive disease and 191 (62.4%) had DCIS only. Of the 115 patients with invasive disease, 5 (4.4%) and 4 (3.5%) had macro- and micrometastases in SLN. On the other hand, of the 191 patients with DCIS, only 1 (0.5%) had a micrometastasis. Predictors of invasive disease in the univariate analysis included having a palpable mass, were varied by biopsy method, having a US hypoechoic mass, MRI enhancement, or MRI large enhanced lesion; the size of the mass enhancement ≥ 1.1cm or a spread of non-mass enhancement ≥ 3.1cm (P = 0.003). Predictors of invasive disease in the multivariate analysis included US hypoechoic mass and MRI large enhanced lesion. We need to perform SLN biopsy for preoperatively diagnosed DCIS when patients have predictors of invasive disease, but SLN biopsy will no longer be essential for patients when they have no predictors of invasive disease.

Avoiding Injury to the Popliteal Neurovascular Bundle in All-Inside Suturing of the Posterior Horn of the Lateral Meniscus: A Magnetic Resonance Imaging Assessment of Portal Selection and Safety

We assessed the risk of injury to the popliteal neurovascular bundle (PNVB) while suturing the posterior horn of the lateral meniscus (PHLM). We simulated all-inside suturing of the PHLM using magnetic resonance imaging of 60 knees. Lines were drawn from the medial and the lateral edges of the patellar tendon to the PHLM at increasing distances from the posterior cruciate ligament (PCL) to simulate suturing device trajectory. Distance from each line to the PNVB was measured (d). A similar analysis was performed using lines drawn from 1cm medial and 1cm lateral to the patellar tendon. We compared the average "d" at increasing distances from the PCL, between the different simulated portal entry points. We have also analyzed the association between different demographic characteristics and the shortest distance from the PVNB to the PHLM. Of 1200 measurements performed, the simulated suturing trajectory transected the PNVB 343 times (28.6%). At 0mm from the PCL, the safest portal was the 1-cm lateral portal (P < .001), with an average "d" of 2.7mm. At 3mm, 6mm, 9mm, and 12mm from the PCL, the safest portal was the 1-cm medial portal (P < .001), with average "d" of 3.8mm, 6.9mm, 10.1mm, and 13.5mm, respectively. Average distance between the PHLM and the PNVB was 7.8mm. Shorter distance between the PHLM and the PNVB was associated with younger age and female sex (P= .014 and .001, respectively). All-inside suturing of the PHLM at 0mm from the PCL is safer with a more lateral portal. Beyond 3mm from the PCL, a more medial portal carries a lower risk to the PNVB. Young and female patients have a shorter distance between the PHLM and the PNVB, suggesting a greater risk for injury to the PNVB. Careful preoperative magnetic resonance imaging assessment may assist in safer portal selection when planning repair of the PHLM. This study describes a magnetic resonance imaging-based risk assessment for injury of the PVNB while suturing the PHLM. It allows the orthopaedic surgeon a better understanding of the anatomic relationship between the popliteal neurovascular bundle and the lateral meniscus and can assist in portal selection and safety.

Can Preoperative Magnetic Resonance Imaging Predict Intraoperative Autograft Size for Anterior Cruciate Ligament Reconstruction? A Systematic Review.

This systematic review explored the utility of preoperative magnetic resonance imaging (MRI) as a tool for predicting intraoperative graft size for anterior cruciate ligament (ACL) reconstruction. Three databases (EMBASE, PubMed, and MEDLINE) were searched in November 2017 for English-language studies of all levels of evidence that aimed to correlate preoperative MRI measurements of common primary ACL autograft sources to intraoperative measurements of the harvested graft. Two reviewers applied predetermined inclusion/exclusion criteria to independently complete title, abstract, and full-text review of eligible studies. Data abstraction, quality assessment, and descriptive statistics are presented. A systematic screen of 930 titles resulted in 14 studies satisfying inclusion/exclusion criteria. These studies examined 762 patients of mean age 28.6 (9-67) years, with 37.3% females. Comparing the correlation of preoperative MRI measurements to intraoperative harvested measures, the strength was very highly positive for quadriceps tendon (QT) (one study, 29 patients, intraclass correlation coefficient [ICC] = 0.96), highly positive for patellar tendon (two studies, 28 patients, ICC: 0.77-0.87), negligible-highly positive for semitendinosus-only tendon (eight studies, 439 patients, r: 0.16-0.81), and negligible-moderately positive for gracilis-only tendon (four studies, 143 patients, r: 0.29-0.59). When combined semitendinosus-gracilis tendon grafts were considered, the correlation ranged from low-very highly positive (10 studies, 517 patients, r: 0.42-0.93). Preoperative MRI assessment of both QT and bone-patellar tendon-bone autografts most highly correlates with intraoperative measurements of autograft diameter. Considerable variability exists when viewing hamstring tendons either individually or together, where most studies indicate at least a moderate correlation. This highlights the advantage of MRI during the preoperative planning process in equipping the surgeon with a better ability to ensure the diameter of the intended autograft will suffice. This is a Level IV study, systematic review of Levels II to IV studies.

ACCURACY OF TRANSPERINEAL ULTRASOUND RELATIVE TO MAGNETIC RESONANCE IMAGING IN EVALUATION OF PERIANAL FISTULAS

Background&#x0D; Ano-rectal fistula is a chronic inflammation of perianal tissues affecting 1/10.000 individuals. Traditionally, treatment is surgical with the possibility of recurrence reaching up to a quarter of cases, therefore preoperative appropriate evaluations and imaging are necessary to decrease recurrence rate. &#x0D; Objectives &#x0D; Determining accuracy of transperineal ultrasound relative to magnetic resonance imaging in evaluation of perianal fistulas. &#x0D; Methods&#x0D; A prospective study was conducted on 51 patients with clinically diagnosed perianal fistula. Transperineal ultrasound (TPUS) and magnetic resonance imaging (MRI) were done for all patients. The following variables were recorded by each of the tests and the results were compared one to one: Firstly the number of the tracts, their relation to the anal sphincters. Secndly the number of internal openings, their sites and distances from the anal verge. Thirdly any associated findings, including perianal abscess, extension (branching) or local inflammatory phlegmons. Descriptive statistics were used. P-values ≤ 0.05 were considered statistically significant.&#x0D; Results&#x0D; Relative to the MRI, the accuracy of TPUS in detection of fistula tract was 96%. Finding of at least one relation of the tract to the anal sphincter was 86.7%, detection of internal opening was 82%, and localization of the internal opening was 82% with comparable result in measuring their distance from the anal verge (P value = 0.15). Lastly the overall accuracy of TPUS to find at least one associated finding was 92%. Among detected associated findings, TPUS was able to accurately classify them with no significant difference between TPUS and MRI (P-Value &gt; 0.05). Three superficial fistula tracts were detected by TPUS and proved by surgical operation while they were undetectable by MRI.&#x0D; Conclusion&#x0D; TPUS is an accurate imaging investigation in the evaluation of perianal fistula and its results was comparable to those of MRI in preoperative assessment of perianal fistula diseases.

Role of intravoxel incoherent motion MR imaging in preoperative assessing HER2 status of gastric cancers.

PurposeTo explore the role of intravoxel incoherent motion (IVIM) magnetic resonance (MR) imaging in evaluating human epidermal growth factor receptor 2 (HER2) status of gastric cancers preoperatively.ResultsThe apparent diffusion coefficient (ADC) and pure diffusion coefficient (D) values correlated positively with HER2 scores of gastric cancers significantly (r = 0.276, P = 0.048; r = 0.481, P < 0.001, respectively). The ADC and D values of HER2 positive gastric cancers were significantly higher than those of HER2 negative tumors (P = 0.033, 0.007, respectively). With a cut-off value of 1.321 and 1.123 × 10−3 mm2/sec, the ADC and D values could distinguish HER2 positive gastric cancers from HER2 negative ones with an area under the curve of 0.733 and 0.762, respectively (P = 0.023, 0.011, respectively).Materials and methodsFifty-three patients with gastric cancers underwent IVIM MR imaging preoperatively. The values of ADC, D, pseudo diffusion coefficient (D*) and perfusion related fraction (f) of the lesions were obtained. Partial correlation test including tumor volume was performed to analyze correlations between IVIM values and HER2 scores excluding the impact of tumor size. IVIM parameters of gastric cancers with different HER2 status were compared using independent samples t test. Diagnostic performance of IVIM parameters in distinguishing HER2 positive gastric cancers from negative ones was tested with receiver operating characteristic analysis.ConclusionsWe confirmed the feasibility of IVIM MR imaging in preoperative assessment of HER2 status of gastric cancers, which might make up the shortfall of biopsy and facilitate personalized treatment for patients with gastric cancers.

Indications of the Magnetic Resonance Method in Breast Pathology.

The high incidence of breast cancer is a known fact. The 5-year survival rate for women with correctly treated breast cancer is 90% around the world, and 50% in Romania, respectively. Correct diagnostic evaluation of the breasts allows for a competent therapeutic management. The primary diagnosis of breast cancer includes clinical examination of the breasts, breast ultrasound and mammography. Magnetic resonance imaging (MRI) examination is not a first line type of investigation, but targeted to selected patient groups. MRI exam is indicated in: screening of breast cancer in women at high risk for breast cancer, in cases with equivocal diagnosis or with contradictory diagnoses at mammography-ultrasound examinations, and in patients with mammographically dense breasts. Mammary MRI exam is the best imaging method in assessing the real dimensions of the initial tumour, in the detection of multifocal and multicentric lesions and of nodular axillary post-lumpectomy lesions. Also, MRI exam is recommended for preoperative breast cancer staging, for assessment of the breast operated on, and for evaluating chemotherapy. Preoperative MRI assessment of the breast reduces the number of surgical interventions required to obtain surgical negative resection margins, decreases breast cancer recurrence rates, and increases long-term life expectancy (survival). MRI is a potential method for monitoring early responses during neoadjuvant therapy, identifying chemoresistant tumours, and allowing guided re-excision, as well as identifying residual tumours after completion of the neoadjuvant therapy course. The exam is very useful in diagnosing mammary pathology in men and is recommended prior to augmentation or reconstructive breast surgery, to appreciate the integrity of the breast implant.

Prognostic Value of Cardiac MR Imaging for Preoperative Assessment of Patients with Severe Functional Tricuspid Regurgitation.

Purpose To explore the prognostic value of cardiac magnetic resonance (MR) imaging in predicting postoperative cardiac death in patients with severe functional tricuspid regurgitation (TR). Materials and Methods This study was approved by the institutional review board, and written informed consent was obtained from all patients. Prospectively collected data included cardiac MR images, New York Heart Association (NYHA) functional class, a comprehensive laboratory test, and clinical events over the follow-up period in 75 consecutive patients (61 women and 14 men; mean age ± standard deviation, 59 years ± 9) undergoing corrective surgery for severe functional TR. Cox proportional hazards models were used to assess the association between cardiac MR parameters and outcomes. Results During a median follow-up period of 57 months (range, 21-82 months), cardiac mortality and all-cause mortality were 17.3% and 26.7%, respectively, with a surgical mortality of 6.7%. Cardiac death risk was lower with a higher right ventricular (RV) ejection fraction (EF) on cardiac MR images (hazard ratio per 5% higher EF = 0.790, P = .048). By adjusting for confounding variables, RV EF remained a significant predictor for cardiac death (P < .05) and major postoperative cardiac events (P < .05). The area under the receiver operating characteristic curve (AUC) confirmed the incremental role of RV EF on cardiac MR images in the prediction of postoperative cardiac death (AUC, 0.681-0.771; P = .041) and major postoperative cardiac events (AUC, 0.660-0.745; P = .044) on top of NYHA class. RV end-systolic volume index was also independently associated with these outcomes but failed to increase the AUC significantly. Conclusion Preoperative assessment of cardiac MR imaging-based RV EF provides independent and incremental prognostic information in patients undergoing corrective surgery for severe functional TR. (©) RSNA, 2016 Online supplemental material is available for this article.

Prognostic significance of a preoperative magnetic resonance imaging assessment of the distance of mesorectal extension in clinical T3 lower rectal cancer.

The aim of this study was to evaluate the association between the mesorectal extensions on high-resolution magnetic resonance imaging (MRI) and the prognosis of patients with clinical T3 lower rectal cancer. Fifty-eight patients with clinical T3 lower rectal cancer were investigated using high-resolution MRI. One radiologist who was blinded to the clinicopathological findings retrospectively examined the MRI-predicted circumferential resection margin (mrCRM) and the distance of mesorectal extension (mrDME) on the scans. If the imaging showed a tumor ≤1mm from the mesorectal fascia, then the mrCRM involvement was defined as potentially present. The tumors were divided into two groups: mrDME ≤4mm and mrDME >4mm. A survival analysis showed that mrCRM-positive patients had a significantly poorer prognosis in the RFS (p<0.01) and LRFS (p<0.01). Patients with mrDME >4mm revealed a significantly poorer prognosis than those with mrDME ≤4mm in the OS (p=0.04), RFS (p<0.01), and LRFS (p=0.04). A multivariate analysis revealed that both mrCRM and mrDME on MRI had a significant impact on the RFS (p=0.01 and 0.03, respectively). The mrDME, as well as the mrCRM, may be an important preoperative prognostic factor for patients with clinical T3 lower rectal cancer.

MRI versus Ultrasonography to Assess Meniscal Abnormalities in Acute Knees

While magnetic resonance imaging (MRI) is often considered the "gold standard" diagnostic imaging modality for detection of meniscal abnormalities, it is associated with misdiagnosis in as high as 47% of cases, is costly, and is not readily available to a large number of patients. Ultrasonographic examination of the knee has been reported to be an effective diagnostic tool for this purpose with the potential to overcome many of the shortcomings of MRI. The purpose of this study is to determine the clinical usefulness of ultrasonography for diagnosis of meniscal pathology in patients with acute knee pain and compare its diagnostic accuracy to MRI in a clinical setting. With Institutional Review Board approval, patients (n = 71) with acute knee pain were prospectively enrolled with informed consent. Preoperative MRI (1.5 T) was performed on each affected knee using the hospital's standard equipment and protocols and read by faculty radiologists trained in musculoskeletal MRI. Ultrasonographic assessments of each affected knee were performed by one of two faculty members trained in musculoskeletal ultrasonography using a 10 to 14 MHz linear transducer. Arthroscopic evaluation of affected knees was performed by one of three faculty orthopedic surgeons to assess and record all joint pathology, which served as the reference standard for determining presence, type, and severity of meniscal pathology. All evaluators for each diagnostic modality were blinded to all other data. Data were collected and compared by a separate investigator to determine sensitivity (Sn), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), correct classification rate (CCR), likelihood ratios (LR[+] and LR[-]), and odds ratios. Preoperative ultrasonographic assessment of meniscal pathology was associated with Sn = 91.2%, Sp = 84.2%, PPV = 94.5%, NPV = 76.2%, CCR = 89.5%, LR(+) = 5.78, and LR(-) = 0.10. Preoperative MRI assessment of meniscal pathology was associated with Sn = 91.7%, Sp = 66.7%, PPV = 84.6%, NPV = 80.0%, CCR = 81.1%, LR(+) = 2.75, and LR(-) = 0.13. Ultrasonography was two times more likely than MRI to correctly determine presence or absence of meniscal pathology seen arthroscopically in this study. Ultrasonography is a useful tool for diagnosis of meniscal pathology with potential advantages over MRI. Based on these data and available portable equipment, ultrasonography could be considered for use as a point-of-injury diagnostic modality for meniscal injuries.

Preoperative Magnetic Resonance Imaging Assessment of Circumferential Resection Margin Predicts Disease-Free Survival and Local Recurrence: 5-Year Follow-Up Results of the MERCURY Study

The prognostic relevance of preoperative high-resolution magnetic resonance imaging (MRI) assessment of circumferential resection margin (CRM) involvement is unknown. This follow-up study of 374 patients with rectal cancer reports the relationship between preoperative MRI assessment of CRM staging, American Joint Committee on Cancer (AJCC) TNM stage, and clinical variables with overall survival (OS), disease-free survival (DFS), and time to local recurrence (LR). Patients underwent protocol high-resolution pelvic MRI. Tumor distance to the mesorectal fascia of ≤ 1 mm was recorded as an MRI-involved CRM. A Cox proportional hazards model was used in multivariate analysis to determine the relationship of MRI assessment of CRM to survivorship after adjusting for preoperative covariates. Surviving patients were followed for a median of 62 months. The 5-year OS was 62.2% in patients with MRI-clear CRM compared with 42.2% in patients with MRI-involved CRM with a hazard ratio (HR) of 1.97 (95% CI, 1.27 to 3.04; P < .01). The 5-year DFS was 67.2% (95% CI, 61.4% to 73%) for MRI-clear CRM compared with 47.3% (95% CI, 33.7% to 60.9%) for MRI-involved CRM with an HR of 1.65 (95% CI, 1.01 to 2.69; P < .05). Local recurrence HR for MRI-involved CRM was 3.50 (95% CI, 1.53 to 8.00; P < .05). MRI-involved CRM was the only preoperative staging parameter that remained significant for OS, DFS, and LR on multivariate analysis. High-resolution MRI preoperative assessment of CRM status is superior to AJCC TNM-based criteria for assessing risk of LR, DFS, and OS. Furthermore, MRI CRM involvement is significantly associated with distant metastatic disease; therefore, colorectal cancer teams could intensify treatment and follow-up accordingly to improve survival outcomes.

The accuracy of magnetic resonance imaging for preoperative deep myometrium assessment in endometrial cancer

ObjectiveTo evaluate the accuracy of preoperative magnetic resonance imaging (MRI) to detect deep myometrial invasion in patients with endometrial cancer. Materials and MethodsWe retrospectively reviewed 66 cases of women with endometrial cancer, who underwent preoperative MRI assessment and surgical staging between January 2006 and October 2010. The MRI findings were then compared with the pathology results. The diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MRI in detecting deep myometrium invasion were evaluated. ResultsThe sensitivity, specificity, accuracy, PPV, and NPV results of MRI for the detection of deep myometrium invasion were 92.52%, 74.35%, 81.81%,71.42%, and 93.54%, respectively, with a kappa of 0.64. In the postmenopausal group, the values were 100%, 55.5%, 74.19%, 61.9%, and 100%. In the premenopausal women, they improved to 85.7%, 90.47%, 88.57%, 88.71%, and 90.47%. The sensitivity (100%) was better than the specificity (55.56%) in the postmenopausal women. The predictive value was markedly higher in the premenopausal women than the postmenopausal women (85.7% vs. 61.9%). ConclusionIn patients with endometrial cancer, a preoperative MRI contributes to accurate staging, allowing planning for the scale of surgery and preoperative counseling. In our study, the pretreatment identification of myometrium invasion provided the opportunity for small-scale surgery in the premenopausal women with early endometrial cancer. However, for the postmenopausal patients, the standard surgical procedure is indicated even if the degree of myometrium invasion is low.

Relationship between MRI-based mechanical activation delays and direct intraoperative measurements of electrical delay in patients undergoing cardiac resynchronization

Background Magnetic Resonance Imaging (MRI) can be used to create maps of left ventricular (LV) mechanical activation delay by analyzing time-dependent radial motion of the myocardium. Local electrograms (EGM) can be obtained during the CRT procedure to measure local electrical activation delay in the LV myocardium. Preoperative MRI assessment of regional dyssynchrony would be useful to guide CRT lead placement. However, the relationship between electrical and mechanical dyssynchrony has not been studied in humans. We hypothesized that intraoperative electrical delay times will correlate with MR-based mechanical delay times.

One millimetre is the safe cut-off for magnetic resonance imaging prediction of surgical margin status in rectal cancer

A pathologically involved margin in rectal cancer is defined as tumour within 1 mm of the surgical resection margin. There is no standard definition of a predicted safe margin on magnetic resonance imaging (MRI). The aim of this study was to assess which cut-off (1, 2 or 5 mm) was the best predictor of local recurrence based on preoperative MRI assessment of the circumferential resection margin (CRM). Data were collected prospectively on the distance between the tumour and mesorectal fascia for patients with documented radiological margin status in the MERCURY study. Positive margin and local recurrence rates were compared for MRI distances from the tumour to the mesorectal fascia of 1 mm or less, more than 1 mm up to 2 mm, more than 2 mm up to 5 mm, and more than 5 mm. The Cox proportional hazard regression method was used to determine the effect of level of margin involvement on time to local recurrence. Univariable analysis showed that, relative to a distance measured by MRI of more than 5 mm, the hazard ratio (HR) for local recurrence was 3·90 (95 per cent confidence interval 1·99 to 7·63; P < 0·001) for a margin of 1 mm or less, 0·81 (0·36 to 1·85; P = 0·620) for a margin of more than 1 mm up to 2 mm, and 0·33 (0·10 to 1·08; P = 0·067) for a margin greater than 2 mm up to 5 mm. Multivariable analysis of the effect of MRI distance to the mesorectal fascia and preoperative treatment on local recurrence showed that a margin of 1 mm or less remained significant regardless of preoperative treatment (HR 3·72, 1·43 to 9·71; P = 0·007). For preoperative staging of rectal cancer, the best cut-off distance for predicting CRM involvement using MRI is 1 mm. Using a cut-off greater than this does not appear to identify patients at higher risk of local recurrence.

Study of the Anatomical Variations of Vertebral Artery in C2 Vertebra With Magnetic Resonance Imaging and Its Application in the C1–C2 Transarticular Screw Fixation

Use of magnetic resonance imaging (MRI) with Constructive Interference in Steady State (CISS) sequence and isometric voxels to demonstrate the anatomic variations of vertebral artery in C2 vertebra. To determine the transarticular screw trajectory on CISS MRI and to identify patients with anatomic variations of vertebral artery in C2 vertebra. Atlantoaxial transarticular screw fixation has been reported to be biomechanically superior to other posterior techniques for atlantoaxial arthrodesis. Vertebral artery injury can be associated with catastrophic sequelae. Anatomic variation of vertebral artery is well recognized and computed tomography scan is the traditional preoperative assessment. However, no report has evaluated the use of MRI in preoperative assessment for the screw trajectories and the anatomic variation of vertebral artery. The 3-dimensional (3D) CISS MRI with isometric voxels was performed in 30 local Chinese patients. The 3D reconstruction images were created to determine the proposed screw trajectories and their relationship with the vertebral arteries. In 12 patients (40%), the vertebral arteries were lying within the screw trajectories prohibiting transarticular screw fixation on at least one side. Bilateral variations with high risk of vertebral artery injuries were found in 6 patients. The remaining 6 patients had unilateral variations prohibiting the insertion of transarticular screws on one side. The 3D CISS MRI with isometric voxels is a safe and simple imaging technique to outline the vertebral arteries in C2. Reconstruction images are easily created and undistorted. It is one of the useful imaging in preoperative planning of transarticular screw fixation and determination of anatomy of vertebral artery.

The “Lateral Gutter Drive-Through” Sign: An Arthroscopic Indicator of Acute Femoral Avulsion of the Popliteus Tendon in Knee Joints

Acute avulsions of the popliteus tendon and the lateral collateral ligament of the femur (peel-off lesion) are common and can both be missed during preoperative assessment and later overlooked during surgery if not specifically sought out. Arthroscopic observation of the direct avulsion sign of the torn end of the popliteus tendon occurs less frequently in patients with acute and subacute injuries. This study describes an arthroscopic sign that detects these tears when they either involve only the popliteal tendon or include the lateral collateral ligament assessed from the lateral gutter of the joint. The “lateral gutter drive-through,” visualized during diagnostic arthroscopy, is described as entering of the arthroscope into the posterolateral compartment through the interval between the popliteal tendon and the lateral femoral condyle. A positive sign indicates (1) the presence of femoral avulsion tears of the popliteal tendon or concomitant lateral collateral ligament, (2) the presence of repairable posterolateral corner tears, and (3) the enablement of mini-open surgery for the repair of these avulsion tears with a recess or reattachment procedure. In addition, arthroscopic evaluation of the lateral compartment and preoperative magnetic resonance imaging assessment are used to eliminate the multiple-level injuries of the popliteus tendon and lateral collateral ligament.

Endometriosis: Contribution of 3.0-T Pelvic MR Imaging in Preoperative Assessment—Initial Results

To determine the accuracy of 3.0-T pelvic magnetic resonance (MR) imaging in the preoperative assessment of endometriosis and to evaluate colon wall involvement after intrarectal gel administration. Institutional review board approval for this study was obtained, and each patient gave written informed consent. Forty-one consecutive patients with clinical suspicion of endometriosis underwent pelvic MR imaging at 3.0 T before surgery. Single-shot and high-spatial-resolution axial T2-weighted, sagittal fat-suppressed T2-weighted, and axial fat-suppressed T1-weighted sequences were performed. T2-weighted sequences were repeated after the rectum was filled with ultrasonographic (US) gel. Two blinded readers interpreted images independently. Image quality was scored by using a four-point scale. Detailed mapping of deep endometriosis was performed. Colon wall infiltration was graded (none, serosa, muscularis, submucosa, mucosa). MR imaging results were compared with surgical and pathologic findings. Interobserver agreement was assessed by using kappa statistics. Nonparametric tests were performed to compare colon wall infiltration scores without and those with US gel and between observers. Twenty-seven of 41 patients had deep endometriosis at surgery and histopathologic examination. Sensitivity, specificity, positive and negative predictive values, and accuracy for the diagnosis of deep endometriosis at MR imaging were 96.3% (26 of 27), 100% (14 of 14), 100% (26 of 26), 93.3% (14 of 15), and 97.6% (40 of 41), respectively. kappa Values ranged from 0.65 to 1.0, depending on the location of deep endometriosis. Colon wall infiltration assessment by both readers correlated well with pathologic findings (Spearman coefficient, >0.93), although median wall involvement scores were lower at pathologic examination than for both readers both before (P = .042 and P = .011) and after (P = .079 and P = .011) intrarectal gel filling. MR imaging of the pelvis at 3.0 T is accurate in the diagnosis and staging of deep endometriosis for the preoperative assessment of patients clinically suspected of having endometriosis.