Inconclusive Magnetic Resonance Imaging Research Articles

Magnetic Resonance Imaging and 99Tc WBC-SPECT/CT Scanning in Differential Diagnosis between Osteomyelitis and Charcot Neuroarthropathy: A Case Series.

Distinguishing between Charcot Neuroarthropathy (CN), osteomyelitis (OM), and CN complicated with superimposed OM in diabetic patients is crucial for the treatment choice. Given that current diagnostic methods lack specificity, advanced techniques, e.g., magnetic resonance imaging (MRI) and 99mTc-HMPAO-WBC Single Photon Emission Computed Tomography (SPECT/CT), are needed. This study addresses the challenges in distinguishing OM and CN. We included diabetic patients with CN and soft tissue ulceration. MRI and 99mTc-HMPAO-WBC SPECT/CT were used for the diagnosis. The patients were classified into three probability levels for OM (i.e., Definite, Probable, and Unlikely) according to the Consensus Criteria for Diabetic Foot Osteomyelitis (CC-DFO). Eight patients met the eligibility criteria. MRI, supported by SPECT-CT and CC-DFO, showed consistency with the OM diagnosis in three cases. The key diagnostic features included the location of signal abnormalities and secondary features such as skin ulcers, sinus tracts, and abscesses. Notably, cases with inconclusive MRI were clarified by SPECT/CT, emphasizing its efficacy in challenging scenarios. The primary objective of this study was to compare the results of MRI and 99mTc-HMPAO-WBC SPECT/CT with the CC-DFO score in the diabetic foot with CN and suspected OM. Advanced imaging offers a complementary approach to distinguish between CN and OM. This can help delineate the limits of the disease for presurgical planning. While MRI is valuable, 99mTc-HMPAO-WBC SPECT/CT provides additional clarity, especially in challenging cases or when metallic implants affect MRI accuracy.

Clinical decision-making based on 11C-methionine PET in recurrent Cushing's disease with equivocal MRI findings.

Diagnosis and accurate localization of recurrent tumors in Cushing's disease (CD) are challenging, especially after multiple transsphenoidal surgeries (TSSs) or radiosurgery. Even experts face difficulties in detecting these recurrent tumors, and a favorable surgical outcome is not guaranteed. In this report, the authors aimed to determine the usefulness of 11C-methionine positron emission tomography (MET-PET) for evaluating patients with recurrent CD with inconclusive magnetic resonance imaging (MRI) lesions and to develop a treatment protocol for these cases. In this retrospective study of patients with recurrent CD in the period between April 2018 and December 2022, the authors assessed the usefulness of MET-PET in determining whether equivocal MRI findings were recurrent tumors or postsurgical cavities and deciding further treatment options. All patients had undergone at least one TSS, and most had undergone multiple TSSs and had pathologically confirmed corticotroph tumors with hypercortisolemia. Overall, 15 patients with recurrent CD (10 females and 5 males) were included, all of whom had undergone MET-PET. All patients had been subjected to multiple treatments, including TSSs or radiosurgeries. Their MRI scans demonstrated less-enhanced lesions that were not confirmed as recurrences even with cutting-edge MRI because they could not be distinguished from postsurgical changes with confidence. MET uptake was positive in 8 patients (9 examinations) and negative in 7. Following MET-PET, repeat TSS was performed in 5 patients. Corticotroph tumors were identified in all 5 patients, even though one of them had negative MET uptake. The MET uptake precisely identified a tumor location on the opposite side of the MRI-suspected lesion in 2 patients. Meanwhile, patients with negative uptake and mild hypercortisolism were only observed. Nonsurgical options were also used in other patients: temozolomide (TMZ) was administered in 2 patients owing to a prior history of multiple TSSs and radiosurgery and the drug-resistant nature of the disease. TMZ was highly effective in these patients; their Cushing's symptoms ameliorated, and their adrenocorticotropic hormone and cortisol levels continued to decline. Interestingly, MET uptake disappeared following TMZ treatment. MET-PET is extremely useful for confirming equivocal lesions on MRI in patients with recurrent CD and for deciding further treatment options. The authors propose a novel protocol based on MET-PET results for treating patients with relapsing CD in whom the recurrent tumors cannot be confirmed with MRI.

P11.75.B PSEUDOPROGRESSION IN A REAL-WORLD GLIOBLASTOMA COHORT: INCIDENCE, MANAGEMENT, PROGNOSTIC IMPACT, AND ASSOCIATED FACTORS

Abstract BACKGROUND Radiotherapy remains a cornerstone in glioblastoma (GBM) management. A continued and unmet need in neuro-oncology is efficient non-invasive methods to differentiate post-radiation magnetic resonance imaging (MRI) changes from progressive disease (PD) in GBM patients. The clinical challenge is two-sided; avoid termination of effective therapy in case of pseudoprogression (PsP) and continuation of ineffective therapy in case of PD. We retrospectively assessed incidence, management, prognostic impact, and associated factors with PsP in a real-world GBM patient cohort. MATERIAL AND METHODS Adult (≥18 years) GBM patients diagnosed in the South-Eastern Health Region of Norway from 2015 to 2018, had received radiotherapy, and follow-up MRIs were included. Patient, tumor, and treatment characteristics were analyzed in relationship to re-evaluated MRI examinations at three and six months post-radiation using response assessment in neuro-oncology criteria. RESULTS PsP incidences at three and six months post-radiation were 20% and 8%, respectively. In adjusted analyses, methylated O6-methylguanine-DNA methyltransferase (MGMT) promoter and absence of neurological deterioration were associated with PsP at both three (p<0.001 and p=0.04, respectively) and six months (p=0.003 and p=0.04, respectively) post-radiation. Patients with PsP at MRI three months post-radiation had a median OS of 24.8 months compared to 11.4 months for patients with PD and 18.7 months in patients with stable disease (SD); the difference was significant only when comparing patients with PsP and PD (p<0.001). There was no survival benefit of treatment change for patients retrospectively evaluated as PD three months post-radiation (p=0.8). Median OS for patients in the PsP group was 31.8 months and thus longer than in the PD group (13.1 months) and the SD group (24.1 months). The difference was only significant when comparing patients with PsP and PD (p<0.001). CONCLUSION PsP incidence in this retrospective material was similar to previous reports. In addition to the previously described correlation of methylated MGMT promoter with PsP, we also found that the absence of neurological deterioration significantly correlated to PsP. Continuation of temozolomide courses did not compromise survival for patients with PD at three months post-radiation; therefore, we recommend continuing adjuvant temozolomide courses in case of inconclusive MRI findings. Funding: European Union's Horizon 2020 Programme European Research Council Grant 758657-ImPRESS.

Abnormal Spontaneous Blood Oxygenation Level Dependent Fluctuations in Children with Focal Cortical Dysplasias: Initial Findings in Surgically Confirmed Cases.

Focal cortical dysplasias (FCD) are a frequent cause of drug-resistant epilepsy in children but are often undetected on structural magnetic resonance imaging (MRI). We aimed to measure and validate the variation of resting state functional MRI (rs-fMRI) blood oxygenation level dependent (BOLD) metrics in surgically proven FCDs in children, to assess the potential yield for detecting and understanding these lesions. We prospectively included pediatric patients with surgically proven FCD with inconclusive structural MRI and healthy controls, who underwent a ten-minute rs-fMRI acquired at 3T. Rs-fMRI data was pre-processed and maps of values of regional homogeneity (ReHo), degree centrality (DC), amplitude of low frequency fluctuations (ALFF) and fractional ALFF (fALFF) were calculated. The variations of BOLD metrics within the to-be-resected areas were analyzed visually, and quantitatively using lateralization indices. BOLD metrics variations were also analyzed in fluorodeoxyglucose-positron emission tomography (FDG-PET) hypometabolic areas. We included 7 patients (range: 3-15 years) and 6 aged-matched controls (range: 6-17 years). ReHo lateralization indices were positive in the to-be-resected areas in 4/7 patients, and in 6/7 patients in the additional PET hypometabolic areas. These indices were significantly higher compared to controls in 3/7 and 4/7 patients, respectively. Visual analysis revealed a good spatial correlation between high ReHo areas and MRI structural abnormalities (when present) or PET hypometabolic areas. No consistent variation was seen using DC, ALFF, or fALFF. Resting-state fMRI metrics, noticeably increase in ReHo, may have potential to help detect MRI-negative FCDs in combination with other morphological and functional techniques, used in clinical practice and epilepsy-surgery screening.

MRI-negative Cushing's Disease: Management Strategy and Outcomes in 15 Cases Utilizing a Pure Endoscopic Endonasal Approach.

BackgroundCushing’s disease (CD) is among the most common etiologies of hypercortisolism. Magnetic resonance imaging (MRI) is often utilized in the diagnosis of CD, however, up to 64% of adrenocorticotropic hormone (ACTH)-producing pituitary microadenomas are undetectable on MRI. We report 15 cases of MRI negative CD who underwent surgical resection utilizing a purely endoscopic endonasal approach.MethodsEndoscopic endonasal transsphenoidal surgery (EETS) was performed on 134 CD cases by a single surgeon. Fifteen cases met inclusion criteria: no conclusive MRI studies and no previous surgical treatment. Data collected included signs/symptoms, pre- and post-operative hormone levels, and complications resulting from surgical or medical management. Data regarding tumor diameter, location, and tumor residue/recurrence was obtained from both pre- and post-operative MRI. Immunohistochemistry was performed to assess for tumor hormone secretion.ResultsAside from a statistically significant difference (P = 0.001) in histopathological results between patients with negative and positive MRI, there were no statistically significant difference between these two groups in any other demographic or clinical data point. Inferior petrosal sinus sampling (IPSS) with desmopressin (DDAVP®) administration was performed on the 15 patients with inconclusive MRIs to identify the origin of ACTH hypersecretion via a central/peripheral (C/P) ratio. IPSS in seven, five and three patients showed right, left, and central side lateralization, respectively. With a mean follow-up of 5.5 years, among MRI-negative patients, 14 (93%) and 12 patients (80%) achieved early and long-term remission, respectively. In the MRI-positive cohort, over a mean follow-up of 4.8 years, 113 patients (94.9%) and 102 patients (85.7%) achieved initial and long-term remission, respectively.ConclusionsSurgical management of MRI-negative/inconclusive Cushing’s disease is challenging scenario requiring a multidisciplinary approach. An experienced neurosurgeon, in collaboration with a dedicated endocrinologist, should identify the most likely location of the adenoma utilizing IPSS findings, followed by careful surgical exploration of the pituitary to identify the adenoma.

Paediatric patients with Cushing disease and negative pituitary MRI have a higher risk of nonremission after transsphenoidal surgery.

Diagnostic workup of Cushing disease (CD) involves imaging evaluation of the pituitary gland, but in many patients no tumour is visualised. The aim of this study is to describe the association of magnetic resonance imaging (MRI) findings with the postoperative course of paediatric and adolescent patients with CD. Patients with a diagnosis of CD at less than 21 years of age with MRI evaluation of the pituitary before first transsphenoidal surgery were included. Clinical, imaging and biochemical data were analysed. One hundred and eighty-six patients with paediatric or adolescent-onset CD were included in the study. Of all patients, 127 (68.3%) had MRI findings consistent with pituitary adenoma, while the remaining had negative or inconclusive MRI. Patients with negative MRI were younger in age and had lower morning cortisol and adrenocorticotropin levels. Of 181 patients with data on postoperative course, patients with negative MRI had higher odds of not achieving remission after the first surgery (odds ratio = 2.6, 95% confidence intervals [CIs] = 1.1-6.0) compared to those with positive MRI. In patients with remission after first transsphenoidal surgery, long-term recurrence risk was not associated with the detection of a pituitary adenoma in the preoperative MRI (hazard risk = 2.1, 95% CI = 0.7-5.8). Up to one-third of paediatric and adolescent patients with CD do not have a pituitary tumour visualised in MRI. A negative MRI is associated with higher odds of nonremission after surgery; however, if remission is achieved, long-term risk for recurrence is not associated with the preoperative MRI findings.

MAGNETIC RESONANCE IMAGING OF LATERAL MENISCAL POSTERIOR ROOT TEARS IN THE ADOLESCENT KNEE: IS THE DIAGNOSIS MISSED, MENTIONED, OR MADE?

Background:The meniscal roots play a vital role in maintaining proper knee kinematics. Neglected meniscal root tears place excess stress on the articular cartilage and increase the risk of premature osteoarthritis. As opposed to medial meniscal root tears, lateral meniscal posterior root tears (LMPRTs) are more likely to be associated with anterior cruciate ligament (ACL) pathology. Failure to identify and address meniscal root tears may place undue loads on ACL grafts and lead to inferior post-surgical outcomes.Purpose:To examine preoperative knee magnetic resonance imaging (MRI) radiologist interpretations for the identification of lateral meniscal root pathology in children and adolescents.Methods:We performed a retrospective review of children and adolescents that underwnent knee arthroscopy between 3/1/2010 and 4/1/2020 and had an arthroscopically confirmed LMPRT. Arthroscopic findings were compared to the reading radiologist’s preoperative MRI interpretations. LMPRTs were graded using the LaPrade classification. ANOVA was performed to assess if body mass index (BMI), open physes, time from injury to MRI, time from MRI to surgery, MRI magnet field strength, musculoskeletal radiologist designation, insurance type and tear grade were associated with the preoperative MRI identification of a LMPRT.Results:During the study period, 1285 knee arthroscopies were performed. 607 of which were ACL reconstructions. 54 children were found to have a LMPRT arthroscopically and all were associated with an ACL tear 54/607 (9%). One patient had 2 preoperative MRIs for a total of 55 MRIs in 54 pateints. Average age was 16 years (range 14-21). Preoperative MRI diagnosis of a LMPRT was made in only 14/55 (25%) and missed in 22/55 (40%). In 19/55 (35%), pathology of the lateral meniscus nonspecific to the root was mentioned. Lateral joint line tenderness was present in 23/54 (46%). There was no statistical significance found in regards to patient BMI, skeletal maturity, time from injury to MRI, time from MRI to surgery, MRI magnet strength, if the radiologist was musculoskeletal fellowship-trained, or insurance type, with a reliable diagnosis. (Table)Conclusion:The final interpretation of preoperative MRIs did not provide a clear definitive diagnosis of a LMPRT in 75 % in patients. As the intraoperative management of LMPRTs can be involved and diverge from standard meniscal work, preoperative diagnosis would be advantageous. All LMPRTs in this study were associated with a concomitant ACL tear. Surgeons caring for ACL tears in children and adolescents should be prepared to treat a LMPRT regardless of a inconclusive MRI interpretation for meniscal root pathology.

Automated fusion of multimodal imaging data for identifying epileptogenic lesions in patients with inconclusive magnetic resonance imaging.

Many methods applied to data acquired by various imaging modalities have been evaluated for their benefit in localizing lesions in magnetic resonance (MR) negative epilepsy patients. No approach has proven to be a stand‐alone method with sufficiently high sensitivity and specificity. The presented study addresses the potential benefit of the automated fusion of results of individual methods in presurgical evaluation. We collected electrophysiological, MR, and nuclear imaging data from 137 patients with pharmacoresistant MR‐negative/inconclusive focal epilepsy. A subgroup of 32 patients underwent surgical treatment with known postsurgical outcomes and histopathology. We employed a Gaussian mixture model to reveal several classes of gray matter tissue. Classes specific to epileptogenic tissue were identified and validated using the surgery subgroup divided into two disjoint sets. We evaluated the classification accuracy of the proposed method at a voxel‐wise level and assessed the effect of individual methods. The training of the classifier resulted in six classes of gray matter tissue. We found a subset of two classes specific to tissue located in resected areas. The average classification accuracy (i.e., the probability of correct classification) was significantly higher than the level of chance in the training group (0.73) and even better in the validation surgery subgroup (0.82). Nuclear imaging, diffusion‐weighted imaging, and source localization of interictal epileptic discharges were the strongest methods for classification accuracy. We showed that the automatic fusion of results can identify brain areas that show epileptogenic gray matter tissue features. The method might enhance the presurgical evaluations of MR‐negative epilepsy patients.

Adolescent Athlete Stress Fractures Associated with Vitamin D Insufficiency: Three Cases with Review of the Literature.

The authors present 3 adolescent athletes who presented with stress fractures in their lower extremities, initially diagnosed as tumors. All 3 patients received an inconclusive magnetic resonance imaging before referral; fractures were confirmed on radiographs and computed tomography. All were found to have vitamin D insufficiency. Vitamin D insufficiency is a global epidemic mainly focused on adults and young-adult athletes. These case reports raise concerns about a growing prevalence of vitamin D insufficiency in adolescents, the potential risk of stress fracture, and the need for screening and possible supplementation in adolescent athletes to improve their bone health.

Quistes pancreáticos: valor agregado de EUS-FNA sobre EUS y RMI. Experiencia de un hospital universitario de alta complejidad

Background. Endoscopic ultrasound (EUS) and magnetic resonance imaging (MRI) are valuable tools in the assessment of cystic pancreatic lesions (CPLs). However, preoperative diagnosis of CPLs still remains a challenge. EUS-guided fine needle aspiration (FNA) provides a method to obtain cyst fluid for analysis to gain additional information. Aim. Compare the concordance between the diagnosis of the cyst by FNA, with that obtained by two diagnostic imaging methods (EUS morphology and MRI). Evaluate if EUS-FNA offered any benefit in cases of inconclusive MRI. Material and methods. We performed a retrospective analysis of a prospectively collected database at a tertiary-care academic medical center between January 2015 and December 2018. All patients who were referred for EUS were reviewed, and patients with diagnosis of pancreatic cysts were included. Imaging, pancreatic cyst fluid (PCF) and follow-up were analyzed. Results. A total of 2238 EUS were performed during the study period and 319 of them had a final diagnosis of pancreatic cyst. FNA was performed on 139 cysts: 62 were diagnosed as mucinous by PCF. The agreement between the diagnosis of the cyst by FNA, with that obtained by EUS morphology was 89.2% (Kappa 0.78, p < 0.001). The concordance between the diagnosis of the cyst by FNA and that obtained by MRI was 72.66 (Kappa 0.41, p < 0.001). From the 319 patients with pancreatic cysts, 60 (18.8%) had inconclusive results on MRI and EUS morphology was able to make a diagnosis in 31 of them. When we analyzed the 139 punctured cysts, MRI was indeterminate in 40 patients and FNA diagnosed 36 of the 40 patients (90%). Discussion. In our study, EUS +/- FNA was superior to MRI specially in cases of inconclusive MRI.

Immune mediated pediatric encephalitis \u2013 need for comprehensive evaluation and consensus guidelines

BackgroundAutoimmune encephalitis is characterized by neuropsychiatric symptoms associated with brain inflammation. The differential is usually broad and Psychiatry often collaborates with Neurology in diagnostic clarification and symptom management. At least 40% of neuroencephalitis cases are of unknown etiology which adds to difficulties in making the right diagnosis and deciding on the appropriate treatment (Granerod et al., Lancet Infect Dis 10:835-44, 2010). The aim of this case series was to present four cases with complicated psychiatric symptomatology and isolated neurologic signs and symptoms, evaluated at a large tertiary medical center and treated for suspected autoimmune encephalitis, demonstrating the complexity of diagnosis and treatment.Case presentationFour diagnostically challenging and heterogeneous cases displayed clinical symptomatology suggestive of autoimmune encephalitis. All cases presented with neurologic and psychiatric symptoms, but had negative autoantibody panels, normal or inconclusive magnetic resonance imaging results and non-specific cerebrospinal fluid changes. All were challenged with immunosuppressive/immunomodulatory treatments with overall poor response rates.ConclusionsThere is a heterogeneous presentation of autoimmune encephalitis in pediatric populations. In the absence of positive findings on testing, individuals who do not meet proposed criteria for seronegative encephalitis may be misdiagnosed, and/or may not respond adequately to treatment. In those cases, comprehensive evaluation and stringent application of consensus guidelines is necessary.

Negative Predictive Value of Contrast-Enhanced Ultrasound of Liver and Kidney Thermal Ablation Sites for Local Tumour Progression During Long-term Follow-up: A Retrospective Consecutive Study

PurposeTo determine negative predictive value (NPV) of contrast-enhanced ultrasound (CEUS) to demonstrate local tumour progression (LTP) at thermal ablation (TA) sites. MethodsOur institutional review board approved this retrospective study; acquisition of consent was waived. Consecutive CEUS examinations performed between 2004-2014 for TA site evaluation on patients who could not undergo enhanced computed tomography (CT) or magnetic resonance imaging (MRI), or had inconclusive CT or MRI, were retrospectively reviewed. Those reported as no abnormal enhancement in or surrounding TA site were included. CEUS examination was considered true-negative based on stability or lack of enhancement/washout on follow-up imaging for at least 1 year, and false-negative (FN), if there was an arterially enhancing focus with wash-out at or surrounding TA site on subsequent follow-up imaging. ResultsStudy population included 56 tumours in 54 patients, 11 women, 43 men; mean age 71 years. Two patients had TA of two different hepatocellular carcinomas. Thirty-six examinations were for hepatic TA and twenty for renal TA. Lesion sizes ranged from 1 cm to 7 cm (mean 3.1 ± 1.2). Mean diameter of 7 recurrences was 13.8 mm. Overall FN rate was 12.5% (7/56). Corresponding numbers were 0% (0/20) for renal TA and 19.4% (7/36) for hepatic TA.Overall NPV of CEUS was 87.5% (49/56) (confidence interval [CI]: 78.8%–96.2%). NPV for renal TA was 100% (20/20) (CI: 100%–100%) and for hepatic TA 81.5% (29/36) (CI: 67.6 %-93.5%). ConclusionIn this cohort, CEUS showed high NPV for exclusion of LTP at renal TA sites. NPV for hepatic TA sites was high but lower than renal TA.

Patent Foramen Ovale and Ischemic Stroke in Patients With Pulmonary Embolism: A Prospective Cohort Study.

Pulmonary embolism (PE) is associated with increased risk for ischemic stroke, but the underlying mechanism remains unclear. The authors hypothesized that paradoxical embolism through patent foramen ovale (PFO) should be the main mechanism. To determine the frequency of recent ischemic stroke in patients with symptomatic PE according to whether PFO was detected. Prospective cohort study with masked assessment of stroke outcomes. (ClinicalTrials.gov: NCT01216423). 4 French hospital centers. 361 consecutive patients with symptomatic acute PE from 13 November 2009 through 21 December 2015. Systematic contrast transthoracic echocardiography (TTE) and cerebral magnetic resonance imaging (MRI) within 7 days after enrollment. Recent symptomatic or silent ischemic stroke was diagnosed on the basis of clinical examination and cerebral MRI showing a hypersignal on the trace diffusion-weighted image with reduction or pseudonormalization of apparent diffusion coefficient. Contrast TTE was conclusive in 324 of 361 patients and showed PFO in 43 patients (13%). The median age was 66 years (interquartile range, 54 to 77 years). In total, 51% of patients (145/284) had associated deep venous thrombosis, 91% (279/306) had cardiovascular risk factors, and 10% (16/151) presented with arrhythmia (no difference between PFO and non-PFO groups). Cerebral MRI was conclusive in 315 patients. Recent ischemic stroke was more frequent in the PFO group than in the non-PFO group (9 of 42 patients [21.4%] vs. 15 of 273 patients [5.5%]; difference in proportions, 15.9 percentage points [95% CI, 4.7 to 30.7 percentage points]). Because of inconclusive contrast TTE or MRI, 46 patients were excluded from analysis. Frequency of recent ischemic stroke in patients with symptomatic PE was higher in patients with PFO than in those without PFO. This finding supports the hypothesis that paradoxical embolism is an important mechanism of ischemic stroke in patients with PFO. French Ministry of Health.

Clinical use of 99mTc-HMPAO-labeled platelets in cerebral sinus thrombosis imaging.

Magnetic resonance imaging (MRI) and computed tomography (CT) are not always conclusive for the detection of cerebral venous sinus thrombosis (CVST). 99mTc-HMPAO-labeled platelets may be useful in cases with high clinical suspicion. Three patients with headaches with or without intraparenchymal hemorrhage that were highly suspected to have CVST, despite inconclusive anatomical imaging, were selected for inclusion in the study. Platelets were extracted by two rounds of centrifugation from 49ml of the patient's whole blood. The platelets were labeled with 99mTc-HMPAO and any unbound 99mTc was removed by centrifugation. The re-suspension of 99mTc-HMPAO-labeled platelets in cell-free plasma was reinjected into the patients. After 2h, planar and single photon emission computed tomography (SPECT) images of the head were obtained. Extensive clots were detected in all three patients, illustrated in the planar image and even clearer in the SPECT images. We propose that 99mTc-HMPAO-labeled platelet scan is a favorable imaging method for patients suspected to have CVST with inconclusive CT and MRI results.

Reliability and Accuracy of MRI in Orthopedics: A Survey of Its Use and Perceived Limitations.

Over the past decade, the use of magnetic resonance imaging (MRI) as a diagnostic tool has been increasing significantly in various fields of medicine due to its wide array of applications. As a result, its diagnostic efficacy and reliability come into question. Specifically, in the field of orthopedics, there has been little discussion on the problems many physicians face while using MRIs in practice. To gauge the perceived limitations of MRI, we designed a decision analysis to analyze the utility of MRIs and estimate the number of inconclusive MRIs ordered within an orthopedic practice to explore potential alternative avenues of diagnosis. A survey of 100 board-certified practicing orthopedic surgeons given at 2 national conferences was designed to assess the value, reliability, and diagnostic utility of MRIs in preoperative planning in shoulder and knee surgery. Of those surveyed, 93% reported that there was believed to be a problem with the accuracy of an MRI in the setting of a prior surgery and/or if previous hardware was present specifically pertaining to the knee or shoulder. The most common indications of concern regarding knee or shoulder MRI reliability among this sample group were previous patient hardware (19%), a previous surgery (16%), and a chondral defect (11%). In addition, when asked how many MRIs were believed to be inconclusive based on previous surgery/hardware alone in the last 6 months of practice, an average of 19 inconclusive MRIs was reported. This study summarizes some of the concerns of MRI use in the orthopedic community and attempts to add a unique perspective on the attitudes, decision-making, and apparent economic problems that they face as well as uncover specific instances where MRIs were determined to be unreliable and incomplete in aiding the diagnosis and treatment algorithm.

Increased LDH5/LDH1 ratio in preoperative diagnosis of uterine sarcoma with inconclusive MRI and LDH total activity but suggestive CT scan: a case report

BackgroundMorcellation of undiagnosed uterine sarcoma is cause of abdominal/pelvic dissemination, residual tumor and recurrence. In the preoperative evaluation of suspect uterine masses, magnetic resonance imaging (MRI) and serum lactate dehydrogenase (LDH) total activity are referred to as the most effective tools, while computed tomography scan (CT) and LDH isoenzymes are less considered in literature.Case presentationA 46 year old woman was admitted to our department with a large uterine mass. Ultrasonography, MRI and LDH total activity did not allow a diagnosis of malignancy, and the woman expressed the wish to avoid hysterectomy. In spite of this, we opted for a total abdominal hysterectomy instead of a laparoscopic myomectomy, due to an elevation of LDH5/LDH1 ratio and CT findings indicative of sarcoma. Histological examination revealed a high grade leiomyosarcoma, confirming our suspicion. Thus, we had avoided the risks linked to morcellation.ConclusionsOur experience suggests that LDH isoenzymes assessment may be relevant in preoperative diagnosis of uterine sarcoma. Further studies are necessary to determine its role in a diagnostic algorithm. We think it may be useful especially for patients with clinical or ultrasonographic suspicion of uterine sarcoma not confirmed by imaging techniques. Furthermore, the role of less considered imaging techniques, such as CT, should not be underestimated in challenging cases.

Endoscopic ultrasonography evaluation for pancreatic cysts: Necessity or overkill?

Incidental pancreatic cysts have become gradually more recognized in clinical practice as a result of increased use of transabdominal ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI). These lesions consist of inflammatory cysts (pseudocysts) and pancreatic cystic neoplasms (PCN) which have been classified as benign, premalignant and malignant. The diagnosis and management strategy of incidentally discovered pancreatic cysts can be challenging as the majority of them are PCN and CT or MRI alone may not be sufficient to provide an accurate diagnosis. Endoscopic ultrasound (EUS)-guided fine-needle aspiration provides a method to obtain cyst fluid for analysis and the recently developed EUS-based technology including contrast-enhanced ultrasound, cystoscopy and needle-based confocal laser endomicroscopy allows endosonographers to gain additional useful information. The current data suggest that EUS evaluation of pancreatic cysts offers some benefits especially in cases of inconclusive CT or MRI.

Usefulness of laser-evoked potentials and quantitative sensory testing in the diagnosis of neuropathic spinal cord injury pain: a multiple case study.

A retrospective study. The aim of this study was to investigate the contribution of laser-evoked potentials (LEPs) and quantitative sensory testing (QST) to the diagnosis of neuropathic pain in patients with spinal cord injury (SCI) and inconclusive magnetic resonance imaging (MRI) findings. A multidisciplinary pain center. QST (DFNS protocol) and Tm-YAG-laser stimulation of the skin were applied within the pain site corresponding with dermatomes of altered sensation. Available MRI scans were reviewed. Thirteen individuals (50±16 years) with SCI were examined. In four cases with no detectable neural lesion on MRI, all QST but three LEP were abnormal. In four patients with poorly defined spinal lesion on MRI, all QST but three LEP only were abnormal. In four cases where pain was not matching adequately with MRI lesions, all patients had abnormal LEP and QST. In one patient showing a spinal cord atrophy, LEP was normal but QST was abnormal. Findings supported the diagnoses at-level (n=5) and below-level (n=8) SCI pain. Spinothalamic tract function assessed by LEP was normal in three cases, but QST was abnormal in all cases. As QST is a psychophysical examination depending on patient cooperation, we suggest that the combination of QST and LEP might be a valuable diagnostic tool to detect lesions of the somatosensory system in a subgroup of patients with neuropathic spinal cord injury pain and inconclusive MRI findings.

Intraosseous lipoma of ilium: A rare case report with review of literature

Intraosseous lipoma (IL) is a rare benign bone lesion, and it constitutes about 0.1% of all bone tumors. The majority of cases are located in the metaphyseal region of the long bones in the lower limbs. We report a rare case of lipoma of the ilium in a 12-year-old male child presenting with mass over the right gluteal region. Meticulous marginal dissection was done, and a pedunculated mass originating from the lower right sacroiliac region was excised in toto. The case was an atypical example of an IL with a large outgrowth involving sacroiliac region with inconclusive magnetic resonance imaging and needle biopsy findings.

Use of gadolinium in placental MRI to improve diagnostic performance for abnormally invasive placentas in patients at risk.

Abnormally invasive placentation (AIP) is a rare but life-threatening condition in which placental tissue surpasses its normal location and abnormally invades the myometrium and neighbouring structures. It is an important cause of excessive postpartum haemorrhage. Its incidence is increasing owing to the growing number of caesarean sections being performed. The diagnosis is reached by the presence of placental ultrasound (US) or magnetic resonance imaging (MRI) signs suggestive of this condition. When the accuracy for the detection of AIP using US and MRI was compared, similar results were obtained. Nevertheless, the performance of both imaging techniques for the detection of AIP is suboptimal. False-negative cases of AIP may represent an increase in maternal morbimortality, as some crucial interventions that are indicated in suspected AIP may not be performed. The indication of a scheduled caesarean delivery in a tertiary referral centre with a multidisciplinary team significantly improves outcomes. False-positives for AIP represent unnecessary maternal–fetal morbidity. For this reason, there is an real need to improve the diagnostic imaging accuracy for AIP. In this study, the authors tested the hypothesis that gadolinium contrast could improve the diagnostic performance of MRI for AIP. One of the main strengths of the study is its novelty, as gadolinium is not frequently used during pregnancy owing to safety concerns. Uncertainty surrounds the risk of possible fetal effects because gadolinium contrast is a water-soluble agent and can cross the placenta into the fetal circulation and amniotic fluid. The main concern is that the duration of fetal exposure is unknown because it can be swallowed from amniotic fluid re-entering the fetal circulation, which could potentially increase the risk of fetal harm. Nevertheless, studies have shown how no adverse perinatal or neonatal outcomes were detected in cases that received this agent during the first trimester (De Santis et al. Acta Obstet Gynecol Scand 2007;86(1):99–101) and how no teratogenic effects were detected in animals exposed to it during pregnancy. Its use during pregnancy has recently been accepted by the European Society of Radiology, the American College of Obstetrics and Gynecology (Committee Opinion No 656; Obstet Gynecol 2016;127(2):e.75–80) and the Society of Obstetricians and Gynaecologists of Canada (Patenaude et al. J Obstet Gynaecol Can 2014;36(4):349–63) when benefits clearly outweigh the possible risks, as may be the case for AIP. The results provided in this study show how the use of gadolinium significantly increased the diagnostic sensitivity and specificity (+12.5% for both), suggesting that the use of this contrast agent could constitute a new reliable way of improving the detection rate of AIP in patients at risk. This should be considered a great achievement that may be helpful particularly in cases of inconclusive MRI scans and that may potentially reduce the morbimortality associated with AIP. Nevertheless, we should keep in mind that technical advances and upcoming studies may show how other MRI contrast agents that do not cross the placenta, or the use of additional MRI sequences, could also help to increase the accuracy of the detection of AIP (Siauve et al. Am J Obstet Gynecol 2015;213:S103) from an expectedly safer and non-invasive perspective. None declared. Completed disclosure of interests form available to view online as supporting information. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.