Presurgical Magnetic Resonance Imaging Research Articles

Main controversies in breast cancer.

In this article, we have reviewed available evidence for diagnosis, treatment, and follow-up in female breast cancer (BC). Into daily clinical practice some controversies are occurred. Especially, in the diagnosis field, despite the fact that the optimal age in which screening mammography should start is a subject of intense controversy, there is a shift toward the beginning at the age of 40 although it is suggested that the net benefit is small for women aged 40 to 49 years. In addition, a promising tool in BC screening seems to be breast tomosynthesis. Other tools such as 3D ultrasound and shear wave elastography (SWE) are full of optimism in BC screening although ultrasonography is not yet a first-line screening method and there is insufficient evidence to recommend the systemic use of the SWE for BC screening. As for breast magnetic resonance imaging (MRI), even if it is useful in BC detection in women who have a strong family history of BC, it is not generally recommended as a screening tool. Moreover, based on the lack of randomized clinical trials showing a benefit of presurgical breast MRI in overall survival, it's integration into breast surgical operations remains debatable. Interestingly, in contrast to fine needle aspiration, core biopsy has gained popularity in presurgical diagnosis. Furthermore, after conservative surgery in patients with positive sentinel lymph nodes, the recent tendency is the shift from axillary dissection to axillary conserving strategies. While the accuracy of sentinel lymph node after neoadjuvant chemotherapy and second BC surgery remains controversial, more time is needed for evaluation and for determining the optimal interval between the two surgeries. Additionally, in the decision between immediate or delayed breast reconstruction, there is a tendency in the immediate use. In the prevention of BC, the controversial issue between tamoxifen and raloxifene becomes clear with raloxifene be more profitable through the toxicities of tamoxifen. However, the prevention of bone metastasis with bisphosphonates is still conflicting. Last but not least, in the follow-up of BC survivors, mammography, history and physical examination are the means of an early detection of BC recurrence. ed.

Integrating MR Imaging Into the Clinical Workup of Pregnant Patients Suspected of Having Appendicitis Is Associated With a Lower Negative Laparotomy Rate

Acute appendicitis is the most common nonobstetric condition requiring surgery in pregnant women. Early surgery based on an initial evaluation results in an increased negative laparotomy rate. However, prolonged observation to improve diagnostic accuracy can lead to increased perforation rates. Imaging should lead to a simultaneous decrease in negative laparotomies and perforations by allowing clinicians to determine earlier and with more certainty whether to perform surgery. Ultrasonography (US) and magnetic resonance imaging (MRI) offer radiation-free alternatives to computed tomography (CT). This retrospective study was performed to determine whether integrating MRI into the assessment of right lower quadrant pain in pregnant patients was associated with improved outcomes measured by the negative laparotomy and perforation rates. The parturients underwent laparotomy or MRI because appendicitis was suspected. Of 187 patients who met initial criteria, 82 had surgery according to the study protocol. A search of the radiology information system yielded 217 MRI examinations; 40 patients had surgery (32 for suspicion of appendicitis and 8 for other conditions). Thus, 32 patients underwent both MRI and surgery, and the study population included 267 unique patients. No contrast material was administered for the MRI. Criteria suggesting appendicitis included an appendix diameter of greater than 6 mm; wall thickness greater than 2 mm; fluid-filled lumen; and surrounding edema, fluid, or abscess. Magnetic resonance imaging reports were categorized as being positive, negative, or equivocal for appendicitis. Charts were reviewed for patients who did not undergo surgery. The frequency of presurgical MRI was used to determine a cutoff between pre-MRI (1996–2003) and post-MRI (2004–2011) cohorts. Negative laparotomy and perforation rates were calculated for both cohorts. Negative laparotomy rate was defined as the percentage of surgeries for presumed appendicitis tabulated as negative laparotomies. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated and adjusted for the prevalence of appendicitis in the pregnant population. Seven MRI examinations were performed between 1996 and 2003, but between 2004 and 2011, 210 MRI examinations were performed. For 1996 to 2011, 50 positive appendectomies, 32 negative appendectomies, and 12 perforations were recorded. The negative laparotomy rate was 55% (17/31) in the pre-MRI cohort and 29% (15/ 51) in the post-MRI group (P = 0.02), representing a 47% decrease in the negative laparotomy rate ([55%–29%]/55%). The perforation rate was 21% (3/14) and 26% (9/35) in the pre- and post-MRI cohorts, respectively (P > 0.99), thus statistically unchanged. The appendix was visualized in 70 (32%) of 217 patients. The sensitivity, specificity, positive predictive value, and negative predictive value of MRI were 89%, 97%, 74%, and 99%, respectively. In the pre-MRI cohort, US was performed in 26 (84%) of 31 patients who had surgery. Three US examinations were true positive; none were false positive. In the post-MRI cohort, US was performed in 41 (80%) of 51 patients who had surgery. Twelve US examinations were true positive, but none were in patients who had MRI. The 2 cohorts did not differ in the use of US (P = 0.4). Magnetic resonance imaging without oral contrast material is a valuable diagnostic tool for evaluating pregnant patients suspected of having appendicitis.

Variables affecting postsurgical prognosis of thoracic myelopathy caused by ossification of the ligamentum flavum

Background contextOssification of the ligamentum flavum (OLF) may result in thoracic myelopathy (TM) because of narrowing of the spinal canal. Because symptoms vary and are subjective, diagnosis of TM caused by OLF is sometimes difficult when based on symptoms and physical examination. Posterior decompression is indicated in patients with TM caused by OLF because it is believed that surgery is the most effective treatment. However, surgical outcomes vary. We are unaware of reports of objective presurgical diagnostic parameters, such as neurologic and radiologic findings, relating to the postsurgical prognosis in patients with TM caused by OLF. PurposeTo determine which presurgical and surgical variables were most closely related to postsurgical prognosis of TM caused by OLF. Study designRetrospective review of the records of the cohort of patients who had undergone surgery from 1988 through 2008 at the University of Toyama Hospital for TM caused by OLF. Patient sampleForty-one patients who had surgery for TM caused by OLF that was progressive, severe, or both and for which the diagnosis was based on clinical, radiologic, and pathologic evaluations. Outcome measuresRelationship between the highest follow-up Japanese Orthopaedic Association (JOA) score for neurologic evaluation and of Hirabayashi's formula to indicate the extent of normalization after surgery with respect to the following 10 variables: age at surgery; sex; duration of presurgical symptoms; complications of diabetes mellitus; complications of hypertension; presence of presurgical hyperreflexia in either or both of the patellar tendon reflex and the Achilles tendon reflex; presurgical impairment of joint position sense in the big toes; number of levels affected by OLF; concurrent spinal lesions including ossification of the posterior longitudinal ligament; and intramedullary change of the spinal cord seen on magnetic resonance imaging (MRI). MethodsMultiple linear analyses were used to evaluate the variables related to postsurgical recovery. ResultsPresurgical impairment of joint position sense in the big toe was the most important predictor of the highest postsurgical JOA score and of the highest percentage recovery rate. The number of affected OLF levels also predicted the postsurgical highest JOA score, but not statistically significantly so. Age at surgery, sex, and duration of symptoms presurgically did not affect postsurgical recovery. Complications of diabetes mellitus or of hypertension did not affect percentage recovery rate. The difference between recovery rate in patients with or without concurrent spinal lesions was not significant. Presurgical hyperreflexia was not correlated with recovery. Postsurgical JOA scores and percentage recovery rates of scores in patients whose presurgical MRIs had shown intramedullary signal change were not statistically significantly different from those whose MRIs had not shown signal change. ConclusionsAn excellent postoperative prognosis is not always possible in patients with TM caused by OLF. It may be important to check for impairment of joint position sense in the big toe, the number of levels affected by OLF, and presurgical intramedullary signal change on MRI before continuing to surgery.

Geometric survey on magnetic resonance imaging of growth hormone producing pituitary adenoma

Apart from the radiologic features regarding size and invasiveness, we had noticed some differences in morphology among types of pituitary adenomas. We conducted this study to verify the differences in radiologic morphology between growth hormone producing pituitary adenomas (GHoma) and nonfunctioning pituitary adenomas (NFoma). Pre-surgical magnetic resonance images (MRIs) were assessed in 50 cases of GHoma and 50 cases of NFoma. Geometric parameters on MRI were set in accordance with sellar anatomy. Intensity of T1-weighted image was not different between the two groups, but hypo-intensity of T2-weighted image was more frequently seen in GHoma. Predominant inferior extension of tumor was seen mostly in GHoma (88 vs. 38%). Extension of the tumor to the superior compartment of cavernous sinus was more frequent in NFoma. Pituitary gland was generally located superior to GHoma and postero-superior to NFoma. Growth characteristics of pituitary adenoma were confirmed to differ between GHoma and NFoma.

MR imaging predictors of molecular profile and survival: multi-institutional study of the TCGA glioblastoma data set.

To conduct a comprehensive analysis of radiologist-made assessments of glioblastoma (GBM) tumor size and composition by using a community-developed controlled terminology of magnetic resonance (MR) imaging visual features as they relate to genetic alterations, gene expression class, and patient survival. Because all study patients had been previously deidentified by the Cancer Genome Atlas (TCGA), a publicly available data set that contains no linkage to patient identifiers and that is HIPAA compliant, no institutional review board approval was required. Presurgical MR images of 75 patients with GBM with genetic data in the TCGA portal were rated by three neuroradiologists for size, location, and tumor morphology by using a standardized feature set. Interrater agreements were analyzed by using the Krippendorff α statistic and intraclass correlation coefficient. Associations between survival, tumor size, and morphology were determined by using multivariate Cox regression models; associations between imaging features and genomics were studied by using the Fisher exact test. Interrater analysis showed significant agreement in terms of contrast material enhancement, nonenhancement, necrosis, edema, and size variables. Contrast-enhanced tumor volume and longest axis length of tumor were strongly associated with poor survival (respectively, hazard ratio: 8.84, P = .0253, and hazard ratio: 1.02, P = .00973), even after adjusting for Karnofsky performance score (P = .0208). Proneural class GBM had significantly lower levels of contrast enhancement (P = .02) than other subtypes, while mesenchymal GBM showed lower levels of nonenhanced tumor (P < .01). This analysis demonstrates a method for consistent image feature annotation capable of reproducibly characterizing brain tumors; this study shows that radiologists' estimations of macroscopic imaging features can be combined with genetic alterations and gene expression subtypes to provide deeper insight to the underlying biologic properties of GBM subsets.

Impact of Presurgical Breast Magnetic Resonance Imaging (MRI) on Surgical Planning - A Retrospective Analysis from a Private Radiology Group

Presurgical bilateral breast MRI is being increasingly utilized in newly diagnosed breast cancer patients to identify the presence of other potentially malignant lesions and thereby guide surgical planning. The authors have performed a retrospective analysis of presurgical MRIs in 445 breast cancer patients, consecutively seen in a community practice setting, to determine what risk factors may be associated with bilateral synchronous breast cancer. Clinical, imaging, surgical, and pathological data were collected on these newly diagnosed patients, who underwent presurgical breast MRIs from November 1, 2008 through October 31, 2009. The MRIs detected 84 incremental (additional) malignancies in 66 (14.8%) patients, including 22 patients in the contralateral breast (4.9%) and 48 patients who had ipsilateral incremental malignancies (10.8%). The presurgical breast MRIs had a sensitivity of 99% and a specificity of 86%. Based on the imaging study and the subsequent biopsy(s), 105 patients (23.6%) had changes in their surgical planning. For those with incremental breast malignancies, the synchronous bilateral breast cancer patients were older (67.5±13.5years, p=0.01). Patients with ipsilateral incremental malignancies were younger (55.6±10.4years of age, p=0.03). A strong family history and ductal carcinoma in situ (DCIS) as the index lesion also appeared to be associated with increased bilateral malignancy detection. The authors conclude that although presurgical MRI remains controversial, our data support its role in surgical planning for newly diagnosed breast cancer patients.

Presurgical EEG-fMRI in a complex clinical case with seizure recurrence after epilepsy surgery

Epilepsy surgery has improved over the last decade, but non-seizure-free outcome remains at 10%–40% in temporal lobe epilepsy (TLE) and 40%–60% in extratemporal lobe epilepsy (ETLE). This paper reports a complex multifocal case. With a normal magnetic resonance imaging (MRI) result and nonlocalizing electroencephalography (EEG) findings (bilateral TLE and ETLE, with more interictal epileptiform discharges [IEDs] in the right frontal and temporal regions), a presurgical EEG-functional MRI (fMRI) was performed before the intraoperative intracranial EEG (icEEG) monitoring (icEEG with right hemispheric coverage). Our previous EEG-fMRI analysis results (IEDs in the left hemisphere alone) were contradictory to the EEG and icEEG findings (IEDs in the right frontal and temporal regions). Thus, the EEG-fMRI data were reanalyzed with newly identified IED onsets and different fMRI model options. The reanalyzed EEG-fMRI findings were largely concordant with those of EEG and icEEG, and the failure of our previous EEG-fMRI analysis may lie in the inaccurate identification of IEDs and wrong usage of model options. The right frontal and temporal regions were resected in surgery, and dual pathology (hippocampus sclerosis and focal cortical dysplasia in the extrahippocampal region) was found. The patient became seizure-free for 3 months, but his seizures restarted after antiepileptic drugs (AEDs) were stopped. The seizures were not well controlled after resuming AEDs. Postsurgical EEGs indicated that ictal spikes in the right frontal and temporal regions reduced, while those in the left hemisphere became prominent. This case suggested that (1) EEG-fMRI is valuable in presurgical evaluation, but requires caution; and (2) the intact seizure focus in the remaining brain may cause the non-seizure-free outcome.

Abstract P3-03-03: A tri-modality imaging assessment algorithm to evaluate neoadjuvant therapy response in patients with operable breast cancer

Abstract Background: To determine the negative predictive value (NPV), positive predictive value (PPV), accuracy, sensitivity and specificity of a pre-surgical tri-modality imaging assessment algorithm to determine complete pathologic response (pCR) post neoadjuvant therapy in patients with operable breast cancer. Methods: A retrospective analysis was performed on data collected from patients receiving neoadjuvant therapy and pre-surgical breast magnetic resonance imaging (MRI), ultrasound (US) and mammography between 2004 and 2010 at our institution. Tri-modality imaging was reviewed by a single blinded breast radiologist and evaluated for predetermined modality specific parameters as defined in Table 1. The NPV, PPV, accuracy, sensitivity, and specificity were calculated on the basis of the final surgical pathology report with a complete pathologic response in the breast defined as no residual invasive disease or in situ disease. Results. Eighty-three tumors in 83 patients with a mean age of 50 (range 27–70) were evaluated. Twenty-three patients had a pCR. The NPV, PPV, sensitivity, specificity, and accuracy of tri-modality imaging algorithm for pCR were 0.87, 0.95, 0.95, 0.87 and 0.93 utilizing a cut-point of ≤ 5 for complete response by imaging. The mean score for patients with pCR was 4.61 (range 3–10) with 3 patients scoring above 5. The mean score for patients with residual disease was 7.73 (range 5–11). Conclusions: A tri-modality imaging scoring algorithm is predictive of complete pathologic response. This algorithm will be tested in a developing prospective trial that will also assess the additive value of tumor bed biopsy in patients who achieve a score of 5 or less. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P3-03-03.

Seizure outcome after extratemporal epilepsy surgery in childhood

The aim of the study was to describe seizure outcome following surgery for focal extratemporal epilepsy and identify factors associated with prolonged postsurgical freedom from seizures. In this retrospective cohort study, children with drug-resistant focal extratemporal epilepsy were treated surgically and followed up in a single tertiary care centre between 1997 and 2008. Eighty children were identified for inclusion in the study (42 males, 38 females; median age 9y 1mo, range 3mo-18y 7mo). The aetiology was identified as focal cortical dysplasia (n=37), low-grade tumour (n=22), tuberous sclerosis (n=9), or non-specific (n=12). Children were followed for a median of 3 years 1 month (range 8mo-10y 7mo) after surgery. Overall, at last follow-up, 50% of the children had been completely seizure free since surgery (Engel class Ia); of these 40 individuals, 15 had discontinued all antiepileptic drugs. Several presurgical factors were associated with a favourable outcome. However, after controlling for confounding factors, aetiology appeared to be the only determinant of long-term seizure outcome as non-specific lesion pathology was associated with seizure recurrence (hazard ratio 10.43; 95% confidence interval 3.26-33.39). In 50% of cases, children with surgically treated drug-resistant extratemporal epilepsies have an excellent long-term outcome. The aetiology of the epileptogenic lesion appears to be the only significant determinant of surgical outcome in this population of children. It is difficult to correctly identify non-specific pathology on presurgical magnetic resonance imaging.

Lateralization of temporal lobe epilepsy using resting functional magnetic resonance imaging connectivity of hippocampal networks

Early surgical intervention can be advantageous in the treatment of refractory temporal lobe epilepsy (TLE). The success of TLE surgery relies on accurate lateralization of the seizure onset. The purpose of this study was to determine whether resting functional MRI (fMRI) connectivity mapping of the hippocampus has the potential to complement conventional presurgical evaluations in distinguishing left from right TLE. In addition, we sought to determine whether this same network might separate patients with favorable from unfavorable postoperative outcomes. Resting fMRI acquisitions were performed on 21 patients with TLE and 15 healthy controls. The patients included seven patients with left TLE and seven patients with right TLE with seizure-free postoperative outcome, and five patients with left TLE and two patients with right TLE with recurring seizures after surgery. Functional connectivity maps to each hippocampus were determined for each subject and were compared between the controls and the seizure-free patients with left TLE and with right TLE. The one network identified was then quantified in the patients with TLE and recurring seizures. The resting functional connectivity between the right hippocampus and the ventral lateral nucleus of the right thalamus was the most statistically significant network to distinguish between seizure-free patients with left TLE and with right TLE with high sensitivity and specificity. This connectivity was also significantly greater in the seizure-free patients with left TLE than the healthy controls. Finally, six of the seven patients in whom seizures recurred after surgery had connectivity values in this network unlike those who were seizure-free. This study identified a region in the ventral lateral nucleus of the right thalamus whose connectivity to the hippocampi separates left from right TLE subjects. This suggests that the quantification of resting-state functional magnetic resonance imaging (MRI) connectivity across this network may be a potential indicator of lateralization of TLE that may be added to other presurgical MRI assessments. Further validation in a larger, independent cohort is required.

Correlation of Histopathology With Magnetic Resonance Imaging in Kienböck Disease

Diagnosis and treatment remain controversial for Kienböck disease. A few reports have correlated magnetic resonance imaging (MRI), which is essential for early diagnosis, and histopathology of Kienböck biopsy specimens, but histopathological correlations of whole lunate bones or histological slices compared with MRI images are lacking. The purpose of this study was to compare presurgical MRI scans with corresponding histological slices of Kienböck-diseased lunates. We excised whole lunates at the time of surgery from 6 patients with Kienböck disease (stage IIIB) undergoing tendon-ball replacement or a Graner procedure. We stained paraffin-embedded, coronally sectioned specimens with hematoxylin-eosin and compared them with presurgical coronal scans using MRI with a 47-mm microscopy surface coil. Toward the center of the lunates, the signal intensity in the proton density-weighted images was reduced, whereas the dorsal and palmar sides of the lunates exhibited no changes in intensity. In correlation, histopathological findings revealed strongly disrupted trabeculae toward the center of the lunates and intact trabeculae in the dorsal side of the lunates. Likewise, the necrotic and vitalized bone exhibited low and high signal intensities, respectively, in the proton density-weighted images; however, in the fast-field echo images, there were no correlations with histopathological observations. Proton density-weighted MRIs but not fast-field echo images using a 47-mm microscopy coil reflected the extent and localization of the necrotic area in Kienböck-diseased lunates, as evidenced by comparison with histological analyses of the lunate specimens. Proton density-weighted MRIs accurately reflect the vascular status of the lunate and may help plan treatment on a case-by-case basis.

Ocular pulse amplitude measured by PASCAL dynamic contour tonometry in patients with a cavernous sinus dural arteriovenous fistula

Ocular pulse amplitude measured by PASCAL dynamic contour tonometry in patients with a cavernous sinus dural arteriovenous fistula

Cell proliferation parameters and apoptosis indices in pituitary macroadenomas.

Pituitary adenomas are usually well-differentiated tumors but may show locally aggressive behavior. To investigate the relationship between proliferation and apoptosis parameters and tumor recurrence in a series of 20 radically resected pituitary macroadenomas (11 functioning, 9 non-functioning). Proliferative activity and DNA ploidy were analyzed by flow cytometry (FCM) on fresh surgical specimens. Immunohistochemistry for Ki-67/MIB-1 and for the anti-apoptotic protein Bcl-2 was performed on paraffin-embedded specimens from the same tumors. Tumor regrowth was evaluated by magnetic resonance imaging (MRI). Six adenomas recurred after surgery, regardless of hormonal hypersecretion. Pre-surgical tumor size was significantly higher in recurrent than in non-recurrent adenomas (p=0.003). Pre-surgical MRI demonstrated cavernous sinus (CS) invasiveness in all recurrent tumors, while none of the non-invasive adenomas recurred (p=0.042, by Fisher's exact test). The DNA content was aneuploid in 5/20 adenomas, one of which recurred. Cell percentages in the S (%SPF) and G2+M (%G2-M) phases and proliferative index (PI) (PI=%SPF+%G2-M) were significantly higher in aneuploid than in diploid adenomas (p<0.05), but no significant differences concerning all FCM parameters were observed between recurrent and non-recurrent adenomas. Similarly, MIB-1 did not show a significant difference of expression between recurrent and non-recurrent adenomas (p=0.33). Bcl-2 immunoreactivity was detected in 12/15 pituitary adenomas, involving 63±35% of tumor cells, regardless of tumor recurrence. In this group of radically resected pituitary macroadenomas, neuroradiological finding of CS invasiveness--but not FCM parameters nor MIB-1 and Bcl-2 expression--is useful for predicting tumor recurrence.

Open Database of Epileptic EEG with MRI and Postoperational Assessment of Foci—a Real World Verification for the EEG Inverse Solutions

This paper introduces a freely accessible database http://eeg.pl/epi, containing 23 datasets from patients diagnosed with and operated on for drug-resistant epilepsy. This was collected as part of the clinical routine at the Warsaw Memorial Child Hospital. Each record contains (1) pre-surgical electroencephalography (EEG) recording (10–20 system) with inter-ictal discharges marked separately by an expert, (2) a full set of magnetic resonance imaging (MRI) scans for calculations of the realistic forward models, (3) structural placement of the epileptogenic zone, recognized by electrocorticography (ECoG) and post-surgical results, plotted on pre-surgical MRI scans in transverse, sagittal and coronal projections, (4) brief clinical description of each case. The main goal of this project is evaluation of possible improvements of localization of epileptic foci from the surface EEG recordings. These datasets offer a unique possibility for evaluating different EEG inverse solutions. We present preliminary results from a subset of these cases, including comparison of different schemes for the EEG inverse solution and preprocessing. We report also a finding which relates to the selective parametrization of single waveforms by multivariate matching pursuit, which is used in the preprocessing for the inverse solutions. It seems to offer a possibility of tracing the spatial evolution of seizures in time.

Ex vivo MR spectroscopic measure differentiates tumor from treatment effects in GBM

The motivation of this study was to address the urgent clinical problem related to the inability of magnetic resonance (MR) imaging measures to differentiate tumor progression from treatment effects in patients with glioblastoma multiforme (GBM). While contrast enhancement on MR imaging (MRI) is routinely used for assessment of tumor burden, therapy response, and progression-free survival in GBM, it is well known that changes in enhancement following treatment are nonspecific to tumor. To address this issue, the objective of this study was to investigate whether MR spectroscopy can provide improved biomarker surrogates for tumor following treatment. High-resolution metabolic profiles of tissue samples obtained from patients with GBM were directly correlated with their pathological assessment to determine metabolic markers that correspond to pathological indications of tumor or treatment effects. Acquisition of tissue samples with image guidance enabled the association of ex vivo biochemical and pathological properties of the tissue samples with in vivo MR anatomical and structural properties derived from presurgical MR images. Using this approach, we found that metabolic concentration levels of [Myo-inositol/total choline (MCI)] in tissue samples are able to differentiate tumor from nontumor and treatment-induced reactive astrocytosis with high significance (P < .001) in newly diagnosed and recurrent GBM. The MCI index has a sensitivity of 93% to tumor in recurrent GBM and delineates the contribution of cellularity that originates from tumor and astrocytic proliferation following treatment. Low levels of MCI for tumor were associated with a reduced apparent diffusion coefficient and elevated choline-N-acetyl-aspartate index derived from in vivo MR images.

Bilateral Epidural Prefrontal Cortical Stimulation for Treatment-Resistant Depression

Treatment-resistant depression presents a serious challenge to both patients and clinicians. The anterior and midlateral prefrontal cortices play complementary roles in integrating emotional and cognitive experiences and in modulating subcortical regions. Both regions offer a distinct opportunity for targeted antidepressant treatments. We chose to pilot the safety and therapeutic benefits of chronic and intermittent epidural prefrontal cortical stimulation (EpCS) in patients with treatment-resistant depression. We enrolled five adults with an average of 5.8 failed antidepressant treatments in their current depressive episode. All subjects underwent comprehensive clinical assessments, detailed neuropsychological testing, and presurgical magnetic resonance imaging. Four cortical stimulation paddle leads were stereotactically placed bilaterally over the anterior frontal poles and midlateral prefrontal cortex. We also acquired a postsurgical computed tomography scan and repeatedly assessed clinical outcomes over time of EpCS as an adjunctive treatment to constant medications. All patients tolerated the therapy. At 7-month follow-up, the average improvement from preimplant baseline on the Hamilton Rating Scale for Depression and the Inventory of Depressive Symptoms-Self-Report were 54.9% (+/- 37.7) and 60.1% (+/- 34.1), respectively. Three implanted subjects reached remission. One patient's left hemisphere leads were explanted 12 weeks postsurgery because of a scalp infection. Bilateral EpCS over anterior and midlateral frontal cortex is a promising new technology for treatment-resistant depression. Future double-blind studies are warranted.

Community-Based Practice Experience of Unsuspected Breast Magnetic Resonance Imaging Abnormalities Evaluated With Second-Look Sonography

The purpose of this study was to assess the utility and efficacy of second-look breast sonography in the evaluation of abnormalities identified on presurgical breast magnetic resonance imaging (MRI) examinations. A retrospective review was performed of 152 presurgical breast MRI examinations having 196 unsuspected abnormalities to identify findings that underwent subsequent breast sonography. Eligible examinations had a suspicious abnormality identified on presurgical MRI and documentation of the location and size of the finding on MRI and subsequent second-look sonography. Fourteen examinations not meeting the criteria were excluded, with 182 abnormalities remaining. Patient medical records were reviewed. Seventy percent (128 of 182) of breast MRI lesions were visible at second-look sonography; 30% (54 of 182) were sonographically occult. Ninety-five percent (121 of 128) of sonographically visible abnormalities underwent breast biopsy. Pathologic examinations of sampled sonographically visible lesions revealed 39 cancers, 9 high-risk lesions, 72 benign lesions, and 1 lesion not specified at surgery; 23% (9 of 128) of cancers were in the contralateral breast. Fifty-four lesions were sonographically occult. Needle biopsy was performed for 93% (50 of 54) of occult lesions, revealing 8 cancers, 1 high-risk lesion, and 41 benign lesions; 3 of the benign lesions did not have sufficient pathologic specimens but were benign at follow-up. Magnetic resonance imaging guidance was used in 86% (43 of 50) of these biopsies. One contralateral cancer was identified in the sonographically occult subset. Of the 182 lesions that underwent second-look sonography, 20% (36 of 182) had a change in management. Second-look sonography has value in the evaluation of abnormalities found on breast MRI. We found enhancements in 70% (128 of 182), yielding 39 cancers.

Locally Advanced Rectal Cancer: MR Imaging in Prediction of Response after Preoperative Chemotherapy and Radiation Therapy

To prospectively differentiate, at magnetic resonance (MR) imaging, patients with locally advanced nonmucinous rectal cancer who will respond to long-course chemotherapy and radiation therapy (CRT) from those who will not respond, with histopathologic results as the reference standard. Institutional review board approval for this study was obtained, and all patients provided written informed consent. High-spatial-resolution T2-weighted MR images were acquired before and 6-8 weeks after CRT in 53 patients (33 men, 20 women; mean age, 63 years; age range, 42-79 years). Patients were categorized as responders to CRT (patients with T3 cancer that converted to T2 or a lower stage, patients with T4 cancer that converted to T3 or a lower stage) or as nonresponders (patients with stable or progressive disease). At the posttreatment MR imaging examination, a decrease in signal intensity was considered to represent a morphologic response with fibrosis. Before CRT and surgery, tumor volume was calculated at MR imaging by multiplying cross-sectional area by section thickness. Tumor length was measured at MR imaging and in the histopathologic specimen. Nodal downstaging was evaluated. The relationship between pathologic response, morphologic MR imaging response, and percentage volume reduction was evaluated with the Mann-Whitney-Wilcoxon two-sample test. Morphologic response assessment with MR imaging achieved a positive predictive value (PPV) of 84.2% (32 of 38) and a negative predictive value (NPV) of 66.7% (10 of 15). Volume reduction extent (> or = 70%) was significantly different between patients in whom disease was downstaged and those in whom it was not downstaged (P = .000005) and showed additional diagnostic value, with an overall accuracy of 86.8% (46 of 53). Presurgical MR imaging and histopathologic tumor length did not show a significant difference. MR imaging accuracy for lymph node (N) stage was 86.8% (46 of 53) on the basis of morphologic criteria. After CRT, morphologic and volumetric evaluation at MR imaging had a high PPV and a low NPV for response assessment. The detection of small clusters of residual tumor cells within fibrosis remains a problem. http://radiology.rsnajnls.org/cgi/content/full/250/3/730/DC1.

IRM morphologique des épilepsies partielles de l’adulte

Magnetic resonance imaging (MRI) is the prominent imaging modality in the field of epilepsy. MRI plays a major role in describing and recognizing the malformations of cortical development and hippocampal sclerosis and has improved epilepsy patient care. MRI is also accurate in detecting the other major epilepsy etiologies (vascular malformations and cicatricial lesions). Presurgical MRI is relevant since it provides a high-resolution study of the brain.

Perception Matches Selectivity in the Human Anterior Color Center

Human ventral cortex contains at least two visual areas selective for color [1]: a posterior center in the lingual gyrus labeled V4 [2-4], V8 [5], or VO-1 [6] and an anterior center in the medial fusiform that has been labeled V4alpha[3, 4]. We examined the properties of the anterior color center using electrical recording and electrical stimulation in a subject with an electrode implanted over the anterior color center, as determined with BOLD fMRI in the same subject. Presentation of visual stimuli evoked local field potentials from the electrode. Consistent with fMRI, the potentials were larger for chromatic than achromatic stimuli. The potentials differed depending on stimulus color, with blue-purple colors evoking the largest response. The spatial receptive field of the electrode was central/parafoveal with a contralateral bias. In the absence of a visual stimulus, electrical stimulation of the electrode produced an artificial visual percept of a blue-purple color near the center of gaze. These results provide direct evidence of a tight link between selectivity and perception in ventral temporal cortex. Electrical stimulation of the anterior color center is sufficient to produce the conscious percept of a color whose identity is determined by the selectivity of the stimulated neurons.