Initial Magnetic Resonance Imaging Studies Research Articles

MRI Tumor Regression Grade Combined with T2-Weighted Volumetry May Predict Histopathological Response in Locally Advanced Rectal Cancer following Neoadjuvant Chemoradiotherapy-A New Scoring System Proposal.

Modern studies focus on the discovery of innovative methods to improve the value of post-treatment magnetic resonance imaging (MRI) in the prediction of pathological responses to preoperative neoadjuvant chemoradiotherapy (nCRT) in locally advanced rectal cancer (LARC). The aim of this study was to assess the potential benefits of combining magnetic resonance tumor regression grade (mrTRG) with T2-weighted volumetry in the prediction of pathological responses to nCRT in LARC. This was a cohort study conducted on patients with histopathologically confirmed LARC in a period from 2020 to 2022. After histopathological verification, all patients underwent initial MRI studies, while the follow-up MRI was performed after nCRT. Tumor characteristics, MRI estimated tumor regression grade (mrTRG) and tumor volumetry were evaluated both initially and at follow-up. All patients were classified into responders and non-responders according to pathological tumor regression grade (pTRG) and mrTRG. A total of 71 patients, mostly male (66.2%) were included in the study. The median tumor volume reduction rate was significantly higher in nCRT-responders compared to non-responders (79.9% vs. 63.3%) (p = 0.003). Based on ROC analysis, optimal cut-off value for tumor volume reduction rate was determined with an area under the curve (AUC) value of 0.724 (p = 0.003). Using the tumor volume reduction rate ≥75% with the addition of response to nCRT according to mrTRG, a new scoring system for prediction of pTRG to preoperative nCRT in LARC was developed. Diagnostic performance of prediction score was tested and the sensitivity, PPV, specificity, and NPV were 81.8%, 56.3%, 71.4%, and 89.7%, respectively. The combination of mrTRG and T2-weighted volumetry increases the MRI-based prediction of pTRG to preoperative nCRT in LARC. The proposed scoring system could aid in distinguishing responders to nCRT, as these patients could benefit from organ-preserving treatment and a "watch and wait" strategy.

Multi-parametric MRI of kidney disease progression for autosomal recessive polycystic kidney disease: mouse model and initial patient results.

Background:Autosomal recessive polycystic kidney disease (ARPKD) is a rare but potentially lethal genetic disorder typically characterized by diffuse renal microcysts. Clinical trials for patients with ARPKD are not currently possible due to the absence of sensitive measures of ARPKD kidney disease progression and/or therapeutic efficacy.Methods:In this study, animal and human MRI scanners were used to obtain quantitative kidney T1 and T2 relaxation time maps for both excised kidneys from bpk and wild type (WT) mice as well as for a pediatric patient with ARPKD and a healthy adult volunteer.Results:Mean kidney T1 and T2 relaxation times showed significant increases with age (p<0.05) as well as significant increases in comparison to WT mice (p<2 × 10−10). Significant or nearly significant linear correlations were observed for mean kidney T1 (p=0.030) and T2 (p=0.054) as a function of total kidney volume, respectively. Initial MRF assessments in a patient with ARPKD showed visible increases in both kidney T1 and T2 in comparison to the healthy volunteer.Conclusions:These preclinical and initial clinical MRI studies suggest that renal T1 and T2 relaxometry may provide an additional outcome measure to assess cystic kidney disease progression in patients with ARPKD.

Ten-year Longitudinal Follow-up MRI Study of Age-related Changes in Thoracic Intervertebral Discs in Asymptomatic Subjects.

Prospective longitudinal study. The aim of this study was to evaluate long-term degenerative changes in intervertebral discs in the thoracic spine in healthy asymptomatic subjects. Longitudinal magnetic resonance imaging (MRI) studies of intervertebral disc degeneration have been reported for the cervical and lumbar but not the thoracic spine. In this longitudinal study (average follow-up 10.0 ± 0.6 years), we assessed degenerative changes in the thoracic spine of 103 volunteers (58 men) of 223 healthy volunteers in the initial MRI study of the thoracic spine (follow-up rate 46.2%). The mean age at the initial study was 45.0 ± 11.5 years (24-77 years). Initial and follow-up thoracic-spine MRIs were graded for the following 4 factors of degenerative changes: decrease in signal intensity of intervertebral disc (DSI), posterior disc protrusion (PDP), anterior compression of dura and spinal cord (AC), and disc-space narrowing (DSN) from T1-2 to T12-L1. We assessed associations between changes in MRI grade and demographical factors such as age, sex, body mass index, smoking habits, sports activities, and disc degeneration in the cervical spine. MRIs revealed that 63.1% of the subjects had degenerative changes in the thoracic intervertebral discs that had progressed at least one grade during the follow-up period. DSI progressed in 44.7% of subjects, PDP in 21.4%, and AC in 18.4% during the 10-year period. No DSN progression was seen. DSI was frequently observed in the upper thoracic spine (T1-2 to T4-5). Disc degeneration was relatively scarce in the lower thoracic spine (T9-10 to T12-L1). PDP was frequently observed in the middle thoracic spine (T5-6 toT8-9). We found significant associations between DSI and cervical-spine degeneration (P = .004) and between AC and smoking (P = .04). Progressive thoracic disc degeneration, observed in 63.1% of subjects; was significantly associated with smoking and with cervical-spine degeneration. 2.

An update on prostate biopsy in the era of magnetic resonance imaging.

Prostate cancer (PCa) is a singular disease owing to absence of imaging technique able to detect suspicious glandular area at higher risk of disease. Nowadays, magnetic resonance imaging (MRI) has been used as a way to detect PCa and simplify targeting prostate biopsy (PB). The aim of this study is to review the most recent data regarding standard BP and MRI-guided PB. A comprehensive systematic MEDLINE search was performed in December 2017 for English-language reports by using the following terms: "prostate biopsy," "multiparametric magnetic resonance imaging," "prostate cancer," "transrectal and transperineal ultrasound," "target biopsy." Previous published reviews and recent published original articles were preferred in order to meet our study scope. Retrieved studies of greater interest were reported in two main sections: standard PB and MRI-guided BP. Thus, the main items regarding PB were analyzed. Briefly, clinical suspicious of PCa is based on prostate specific antigen level and digital rectal examination findings although a PCa risk assessment through a nomogram risk calculator is nowadays advised. Ten-eighteen biopsy cores, depending on prostate volume, and peripheral sampling seem the suitable scheme for initial biopsy while a saturation template (>20 cores including transitional prostate area) is widely used in case of repeat PB. Performing a local anesthesia is now the standard of care with several available techniques. No difference exists in term of PCa detection rate between transperienal and transrectal approaches however the last one is mostly used. The use of MRI-guided biopsy seems to be a promising imaging technique able to identify an index lesion at higher suspicious of PCa. In particular, MRI shows a higher accuracy than standard PB in the detection of clinically significant PCa. No general consensus exists on which MRI-guided biopsy should be used with three different ways currently available to take biopsy core. However, the initial MRI cognitive PB has been replaced by fusion MRI technique to guide biopsy with reproducible results. Absence of standardization founded in initial MRI studies has been recently revised by introduction of common criteria to assess PCa presence on MRI. PB is the cornerstone in diagnosis and management of PCa. Although ultrasound transrectal and transperineal PB are still considered as the standard, emerging data confirm the role of MRI-guided biopsy, particularly in patients with a previous negative biopsy. However, MRI costs and the moderate inter-reader reproducibility of the exam are still significant concerns requiring further studies to define the right role of MRI in the PCa diagnostic pathway.

Evaluation of the fetal abdomen by magnetic resonance imaging. Part 1: malformations of the abdominal cavity.

Although ultrasound continues to be the mainstay modality for the evaluation of fetal disorders, fetal magnetic resonance imaging (MRI) has often been used as a valuable adjunct in recent years. The exponential growth of the use of fetal MRI has been facilitated by technological advancements such as ultrafast T2-weighted sequences and diffusion-weighted imaging. Fetal MRI can achieve results that are comparable to or better than those of ultrasound, particularly in cases of maternal obesity, severe oligohydramnios, or abnormal fetal position. Because of its superior soft tissue contrast, wide field of view, and multiplanar imaging, fetal MRI is able to evaluate the large fetal organs, such as the lungs, liver, bowel, and kidneys. In addition, fetal MRI allows large or complex malformations to be examined, facilitating the understanding of the malformation within the context of the body as a whole. Initial fetal MRI studies were focused on the central nervous system. With advances in software and hardware, fetal MRI gained importance in the evaluation of the fetal abdomen. The purpose of this article is to review the recent literature and developments in MRI evaluation of the fetal abdomen, with an emphasis on imaging aspects, protocols, and common clinical indications.

A new point of view for mosaicplasty in the treatment of focal cartilage defects of knee joint: honeycomb pattern.

Background A focal full thickness cartilage lesion of knee joint is one of the commonly seen intraarticular pathologies among the joint cartilage problems. Osteochondral autograft transfer mosaicplasty is a method which has satisfactory outcomes among the treatment preferences of cartilage defects. In spite of the favorable clinical results there are some pitfalls of mosaicplasty treatment especially in cases of large defects. One of the major problems of the classical OAT mosaicplasty is the gap spaces between the plugs. The objective of the present study is to report the early clinical and radiological outcomes and to evaluate the clinical application of a new hexagonal osteochondral graft system (HOGS) with the hypothesis of improvement of the OAT mosaicplasty method with the use of hexagonally shaped plugs. The study has intended to answer two questions. (1) Does mosaicplasty with the new HOGS has favorable early clinical outcomes? (2) Is it possible to arrange the osteochondral autografts without leaving gap spaces by using hexagonal pattern in OAT mosaicplasty?Patients and methodsWe designed a retrospective study to report analysis of early outcomes of the initial case series of OAT mosaicplasty by using a new HOGS. Six male individuals with the diagnosis of osteochondral defect and treated with HOGS and reached sixth month follow-up formed the basis of the study. The clinical status of the patients were evaluated with IKDC score. The radiological evaluations were carried out with direct X-rays and magnetic resonance imaging (MRI) studies. The mosaicplasty procedures were carried out via standard surgical method of classical OAT mosaicplasty by using the HOGS following a diagnostic arthroscopy in the same session. The inclusion criteria was a full thickness osteochondral lesion of femoral condyle between 1.5 and 6 cm2 and completion of 6 month follow-ups. The patients having deformities around the knee or major ligament lesions were excluded. MOCART scoring system was used for the evaluation of follow-up MRI findings. The clinical status of the patients were evaluated with IKDC scores.ResultsThe mean age of the patients was 40.8 (±5.2) years and the mean duration of the symptoms on presentation was 16 (±4.3) months. On the initial MRI studies mean defect area was measured 3.7 cm2 (±0.9) which was compatible with arthroscopic findings. During the surgical procedures it was possible to fill the defect area completely. The mean number of plugs in this series was 4.8 (±1.1). We did not faced with insufficient donor reserve problem in any of the cases. On the sixth month follow-up physical examination there was no limitation of the knee joint range of motion in the cases. All patients were able to bear weight on to their operated extremities without pain. The mean postoperative IKDC score improvement was 70.2 (±3.5) which shows significant improvement compared to preoperative scores. On the control MRI studies the bone integration of the hexagonal plugs were complete the cartilage continuity of the articular surfaces were intact and the grafts were well incorporated in all cases. The mean MOCART score on the 6th month MRI studies was 65.8 (±4.1).ConclusionThe early outcomes of OAT mosaicplasty with HOGS are comparable to studies on the classical mosaicplasty. According to our observations in this study we can say that the gap space left between the cylindrical plugs can be solved by using hexagonal prism shaped plugs.

Small temporal pole encephalocele: A hidden cause of "normal" MRI temporal lobe epilepsy.

Small temporal pole encephalocele (STPE) can be the pathologic substrate of epilepsy in a subgroup of patients with noninformative magnetic resonance imaging (MRI). Herein, we analyzed the clinical, neurophysiologic, and radiologic features of the epilepsy found in 22 patients with STPE, and the frequency of STPE in patients with refractory focal epilepsy (RFE). We performed an observational study of all patients with STPE identified at our epilepsy unit from January 2007 to December 2014. Cases were detected through a systematic search of our database of RFE patients evaluated for surgery, and a prospective collection of patients identified at the outpatient clinic. The RFE database was also employed to analyze the frequency of STPE among the different clinical subgroups. We identified 22 patients with STPE (11 women), including 12 (4.0%) of 303 patients from the RFE database, and 10 from the outpatient clinic. The median age was 51.5 years (range 29-75) and the median age at seizure onset was 38.5 years (range 15-73). Typically, 12 (80%) of 15 patients with left STPE reported seizures with impairment of language. Among the RFE cases, STPE were found in 9.6% of patients with temporal lobe epilepsy (TLE), and in 0.5% of those with extra-TLE (p = 0.0001). STPEs were more frequent in TLE patients with an initial MRI study reported as normal (23.3%) than in those with MRI-visible lesions (1.4%; p = 0.0002). Stereo-electroencephalography was performed in four patients, confirming the localization of the epileptogenic zone at the temporal pole with late participation of the hippocampus. Long-term seizure control was achieved in four of five operated patients. STPE can be a hidden cause of TLE in a subgroup of patients with an initial report of "normal" MRI. Early identification of this lesion may help to select patients for presurgical evaluation and tailored resection.

Subcellular Partitioning and Analysis of Gd3+-Loaded Ultrashort Single-Walled Carbon Nanotubes.

Magnetic resonance imaging (MRI) is of vast clinical utility, with tens of millions of scans performed annually. Chemical contrast agents (CAs) can greatly enhance the diagnostic potential of MRI, and ∼50% of MRI scans use CAs. However, CAs have significant limitations such as low contrast enhancement, lack of specificity, and potential toxicity. Recently developed, Gd3+-loaded ultrashort single-walled carbon nanotubes, also referred to as gadonanotubes or GNTs, exhibit ∼40 times the relaxivities of clinical CAs, representing a potential major advance in clinically relevant MRI CA materials. Although initial cytotoxicity and MRI studies have suggested great promise for GNTs, relatively little is known regarding their subcellular interactions, which are crucial for further, safe development of GNTs as CAs. In this work, we administered GNTs to a well-established human cell line (HeLa) and to murine macrophage-like cells (J774A.1). GNTs were not acutely cytotoxic and did not reduce proliferation, except for the highest exposure concentration of 27 μg/mL for J774A.1 macrophages, yet bulk uptake of GNTs occurred in minutes at picogram quantities, or millions of GNTs per cell. J774A.1 macrophages internalized substantially more GNTs than HeLa cells in a dose-dependent manner, and Raman imaging of the subcellular distribution of GNTs revealed perinuclear localization. Fluorescence intensity and lifetime imaging demonstrated that GNTs did not grossly alter subcellular compartments, including filamentous-actin structures. Together, these results provide subcellular evidence necessary to establish GNTs as a new MRI CA material.

Systemic Lupus Erythematosus: Prediction by MRI of the Subsequent Development of Brain Lesions

Many patients with systemic lupus erythematosus (SLE) manifest the recurrence of new brain lesions on follow-up magnetic resonance imaging (MRI) scans. We assessed whether the initial MRI findings help to predict the subsequent development of brain lesions in patients with SLE. We enrolled 64 patients with SLE who had undergone initial and follow-up MRI studies. Two radiologists reviewed and categorized the initial MRI findings and divided the patients into those with no lesions on the initial and follow-up MRI scans (group A, n = 18), those with lesions on the initial scans only (group B, n = 32), and those with lesions on the first and new lesions on the follow-up MRI scans (group C, n = 14). We then looked for independent predictors of the subsequent development of brain lesions, such as antiphospholipid syndrome (APS) and findings on the initial MRI studies. The incidence of lacunar and localized cortical infarcts was significantly greater in group C than group B (50% vs. 0%, P < .001 and 50% vs. 9%, P < .05, respectively). Multivariate logistic regression analysis indicated that lacunar or localized cortical infarcts on the initial MRI scans were independent predictors of the subsequent development of brain lesions (odds ratio [OR]: 5.412, 95% confidence interval [CI]: 1.18-24.85, P = .03), whereas the presence of APS was not (OR: 0.621, 95% CI: 0.18-2.19). The presence of lacunar and/or localized cortical infarcts on initial MRI scans may predict the development of new brain lesions in patients with SLE.

Tumor targeting and imaging with dual-peptide conjugated multifunctional liposomal nanoparticles

BackgroundThe significant progress in nanotechnology provides a wide spectrum of nanosized material for various applications, including tumor targeting and molecular imaging. The aim of this study was to evaluate multifunctional liposomal nanoparticles for targeting approaches and detection of tumors using different imaging modalities. The concept of dual-targeting was tested in vitro and in vivo using liposomes derivatized with an arginine-glycine-aspartic acid (RGD) peptide binding to αvβ3 integrin receptors and a substance P peptide binding to neurokinin-1 receptors.MethodsFor liposome preparation, lipids, polyethylene glycol building blocks, DTPA-derivatized lipids for radiolabeling, lipid-based RGD and substance P building blocks and imaging labels were combined in defined molar ratios. Liposomes were characterized by photon correlation spectroscopy and zeta potential measurements, and in vitro binding properties were tested using fluorescence microscopy. Standardized protocols for radiolabeling were developed to perform biodistribution and micro-single photon emission computed tomography/computed tomography (SPECT/CT) studies in nude mice bearing glioblastoma and/or melanoma tumor xenografts. Additionally, an initial magnetic resonance imaging study was performed.ResultsLiposomes were radiolabeled with high radiochemical yields. Fluorescence microscopy showed specific cellular interactions with RGD-liposomes and substance P-liposomes. Biodistribution and micro-SPECT/CT imaging of 111In-labeled liposomal nanoparticles revealed low tumor uptake, but in a preliminary magnetic resonance imaging study with a single-targeted RGD-liposome, uptake in the tumor xenografts could be visualized.ConclusionThe present study shows the potential of liposomes as multifunctional targeted vehicles for imaging of tumors combining radioactive, fluorescent, and magnetic resonance signaling. Specific in vitro tumor targeting by fluorescence microscopy and radioactivity was achieved. However, biodistribution studies in an animal tumor model revealed only moderate tumor uptake and no additive effect using a dual-targeting approach.

Conus medullaris syndrome after epidural steroid injection: Case report

BackgroundGiven the risk of paralysis associated with cervical transforaminal injection, is it time to reconsider transforaminal injections of the lumbar spine? Arguments for discontinuing lumbar injections have been discussed in the anesthesia literature, raising concern about the risks of epidural steroid injections (ESIs). MethodsIn a 47-year-old man, paraplegia of the lower extremities developed, specifically conus medullaris syndrome, after he underwent an ESI for recurrent pain. Correct needle placement was verified with epidurography. Immediately after the injection, the patient felt his legs “going dead”; paraplegia of the lower extremities was noted. ResultsAn initial magnetic resonance imaging study performed after the patient was transferred to the emergency department was unremarkable. However, a later neurosurgical evaluation showed conus medullaris syndrome, and a second magnetic resonance imaging study showed the conus infarct. We conducted a search of the PubMed database of articles from 2002 to 2011 containing the following keywords: complications, lumbar epidural steroid injection(s), cauda equina syndrome, conus medullaris infarction, spinal cord infarction, spinal cord injury, paralysis, paresis, plegia, paresthesia, and anesthesia. ConclusionsSummarizing this case and 5 similar cases, we weigh the potential benefits and risks of ESI. Although one can safely assume that this severe, devastating complication is rare, we speculate that its true incidence remains unknown, possibly because of medicolegal implications. We believe that the rarity of this complication should not preclude the continued use of transforaminal ESI; rather, it should be emphasized for discussion with patients during the consent process.

Prediction of Growth Rate of Solid Renal Masses: Utility of MR Imaging Features—Preliminary Experience

To retrospectively assess the relationships between a number of magnetic resonance (MR) imaging features and growth rate of solid renal masses in patients undergoing active surveillance. This retrospective study was institutional review board approved, with waiver of informed consent. This study was HIPAA compliant. Forty-four patients (mean age, 70 years ± 13 [standard deviation]; 31 men, 13 women) with 47 solid renal masses measuring at least 1 cm who underwent two contrast material-enhanced MR imaging studies at least 3 months apart were included. The initial MR imaging study was evaluated independently by two radiologists for an array of imaging features, with differences resolved by consensus. Later, the two readers in consensus measured tumor volume on the first and last study to calculate tumor doubling time (DT). Associations between MR imaging features and DT were assessed by using generalized estimating equations and mixed model analyses. Interreader agreement was assessed with k coefficients. κ coefficients ranged from 0.62 to 0.92. Mean DT of the 47 masses was 530 days. Five (11%) masses decreased in size. Twenty-five of 47 masses were classified as slow growing on the basis of a DT of more than 2 years. There was significantly slower growth among masses showing homogeneity on T2-weighted images (P = .036) and a nearly significant slower growth rate among masses showing homogeneity on postcontrast images (P = .065) and hypointensity on T2-weighted images (P = .074). There was a significant correlation between initial volume and growth rate among lesions larger than 3 cm (r = 0.79, P = .041) but not among smaller lesions (r = -0.02, P = .911). Multivariate analysis identified age (odds ratio = 0.92, P = .015) and homogeneity on T2-weighted images (odds ratio = 4.47, P = .037) as independent predictors of slow growth. The results suggest MR imaging features may have a role in predicting growth rate of solid renal masses during active surveillance.

Spontaneous Regression and Regrowth of Central Nervous System Lymphomatoid Granulomatosis -Case Report-

A 74-year-old woman presented with central nervous system (CNS) lymphomatoid granulomatosis (LYG) that spontaneously regressed and then regrew shortly thereafter. Initial magnetic resonance imaging studies showed a well demarcated, round, enhanced lesion with perifocal edema in the left temporal lobe. The enhanced lesion and perifocal edema had drastically regressed without treatment at follow-up examination. Two months later, the lesion reappeared and was larger, so was completely removed via left fronto-temporal craniotomy. The histological diagnosis was CNS LYG. CNS LYG should be considered in the differential diagnosis of spontaneously regressing brain tumors.

A change in pituitary magnetic resonance imaging protocol detects ACTH‐secreting tumours in patients with previously negative results

While detection of pituitary tumours with magnetic resonance imaging (MRI) may reduce diagnostic costs and improve surgical outcomes for patients with Cushing's disease, the optimal T1-weighted spin-echo (SE) MRI protocol remains unknown. We hypothesized that specific MR scanning parameters influence detection of corticotropinomas. Between December 1997 and November 2004, 21 of 84 consecutive patients with Cushing's disease had a falsely negative initial pituitary MRI study and a lesion identified subsequently at the National Institutes of Health Clinical Center. This study retrospectively reviewed and compared technical parameters used for the two pituitary T1-weighted SE MRIs in 18 patients with available scans. Repetition time (TR)/echo times (TE), field of view (FOV), matrix size, magnetic field strength, slice thickness, use of gadolinium contrast and the time interval between studies were recorded. The MRI interscan interval was 5.4 +/- 1.1 months. All scans used gadolinium, matrix sizes were similar and nearly all had 3-mm thick slices. Parameters that differed between the NIH- and externally performed scans were: TR (400 ms vs. 492 +/- 19 ms, P = 0.0002); TE (10.3 +/- 0.5 vs. 17.2 +/- 1.2 ms, P = 0.0003); FOV (12 x 12 cm vs.17 +/- 0.6 x 18 +/- 0.7 cm, P < 0.0001). Immunohistochemistry of tumours resected at transsphenoidal surgery confirmed all to be corticotropinomas. Not all 'T1-weighted SE' scans are equally accurate. MRI technique, particularly FOV and TR/TE value, influences results. We recommend that endocrinologists consider pituitary MRI parameters when interpreting the results.

Multiple sclerosis risk in radiologically uncovered asymptomatic possible inflammatory-demyelinating disease

Background Natural history of patients with incidentally discovered lesions that fulfill magnetic resonance imaging (MRI) criteria for multiple sclerosis (MS) in the absence of objective clinical symptoms suggestive of central nervous system (CNS) inflammatory-demyelinating disease is not well defined. Objective We evaluated the risk of developing symptomatic MS in patients with radiologically uncovered asymptomatic possible inflammatory-demyelinating disease (RAPIDD). Methods We identified and longitudinally followed a cohort of 22 patients from two tertiary care MS centers: Istanbul University, Cerrahpasa School of Medicine, Istanbul, Turkey, and Mayo Clinic, Rochester, Minnesota, after an initial MRI study fulfilling the Barkhof–Tintore MRI criteria completed for other reasons unrelated to MS. Results Eight of 22 patients developed an objective clinical symptom consistent with a CNS inflammatory-demyelinating syndrome and fulfilled dissemination in space and time criteria for definite MS. Median age at the time of diagnosis of MS was 44.8 years (range 28.3–71.4 years). Time taken for the development of definite MS was studied by survival analysis. Cumulative event rates were; 12 months: 9%, 24 months: 15%, 36 months: 30.4%, and 60 months: 44.6%. Six of 22 patients were followed beyond 60 months. Two of these six patients developed MS later (at 66 and 112 months, respectively). Three patients remained asymptomatic despite follow-up of 10 years. Conclusions Patients with RAPIDD develop MS at a similar rate to treated patients (and less frequently than placebo groups) with clinically isolated syndromes from prior randomized controlled studies. Some patients with RAPIDD continue to have radiological evolution of subclinical disease without MS symptoms despite long follow-up periods.

A reversible lesion of the corpus callosum splenium with adult influenza-associated encephalitis/encephalopathy: a case report

IntroductionInfluenza virus-associated encephalitis/encephalopathy is a severe childhood illness with a poor prognosis. Adult case reports are rare and, to date, there have been no reports of adults with a mild subcortical encephalopathy with reversible lesions of the corpus callosum splenium.Case presentationA previously healthy 35-year-old man presented with acute progressive tetraplegia, transcortical motor aphasia and a mild decrease in his consciousness during his recovery after receiving oseltamivir phosphate treatment, and influenza type A antiviral medication. The initial magnetic resonance imaging study at day 1 showed symmetrical diffuse lesions in the white matter and a lesion on the central portion of the corpus callosum splenium. These findings had resolved on follow-up studies at day 8 and day 146. His neurological deficits mostly recovered within 12 hours following methylprednisolone pulse therapy. The levels of interleukin-6 and interleukin-10 in his blood and cerebrospinal fluid were initially elevated, but rapidly decreased to normal levels by day 8.ConclusionIt is important for clinicians to recognize that even in adulthood, the subcortical encephalopathy observed during the therapeutic treatment for influenza type A infection can occur in conjunction with a reversible lesion of the corpus callosum, which may recover quickly. In addition, the cytokine storm in the blood system and the corticospinal cavity may play an important role in the etiology of the disease process.

Magnetic resonance‐guided, vacuum‐assisted breast biopsy

The objective of this study was to determine the accuracy, reproducibility, and clinical value of magnetic resonance (MR)-guided, vacuum-assisted breast biopsy (MR-VAB) in a prospective, multicenter study. In 5 European centers, MR-VAB was performed or attempted on 538 suspicious lesions that were visible or could targeted only by MR imaging (MRI). Verification of malignant or borderline lesions included reexcision of the biopsy cavity. Benign biopsy results were verified by retrospective correlation of histology with preinterventional and postinterventional MRI studies. Follow-up of 24-48 months (median, 32 months) was available for 491 of 538 patients. MR-VAB was unsuccessful or was not completed in 21 of 538 patients, for which an immediate repeat biopsy was recommended. Five hundred seventeen of 538 performed VAB procedures (96%) were successful. Histology yielded 138 (27%) malignancies, 17 (3%) atypical ductal hyperplasias, and 362 (70%) benign entities. No false-negative diagnoses occurred among the 517 successful MR-VAB procedures. The positive predictive value of VAB depended on patient preselection, which differed according to the indication for the initial MRI study. The results of this study indicated that MR-VAB offers excellent accuracy. Small lesion size did not prove to be a limitation.

Dorsolateral prefrontal and superior temporal volume deficits in first–episode psychoses that evolve into schizophrenia

Regions with a likely involvement in schizophrenia may differ between patients with first-episodes of psychosis respectively with and without evolution into schizophrenia following the initial episode. We have used magnetic resonance imaging (MRI) to assess the volumes of dorsolateral prefrontal (DLPF) and superior temporal gyrus (STG) in a group of 37 first-episode psychotic patients. After an initial MRI study performed by the time of the first episode, the subjects were followed for two years. After this period 22 cases were diagnosed with schizophrenia, while the other 15 did not show clinical evidence for this illness. A Talairach-based tool was used for segmentation and volumetry of the MRI scans. A group of 44 healthy controls was used for comparison and, using lineal regression, to control for the normal effects of age and intracranial volume on the regional parameters of the patients. By the time of their first episode, patients with schizophrenia had significantly less grey matter in the right DLPF and STG regions as compared to both controls and FE without schizophrenia. Nevertheless, these parameters could not predict final diagnosis in a discriminant analysis model. Our findings indicate that subtle structural defects are already found by the time of the first psychotic break in schizophrenia, although clinical implications for these differences seem unclear.

Hypoxic-ischemic encephalopathy: Correlation of serial MRI and outcome

Twenty-four patients with hypoxic-ischemic encephalopathy were examined with serial magnetic resonance imaging up to 4 years of age. Magnetic resonance imaging studies were performed in the neonatal period, at the fourth month and the fourth year of age, and the findings were compared with the patients' neurodevelopmental outcome at the fourth year of age. Periventricular signal alterations and deep gray matter involvement were usually evident in the initial magnetic resonance imaging studies, and encephalomalacia, periventricular leukomalacia, and atrophy were the common findings on follow-up magnetic resonance imaging studies. In the patients with hypoxic-ischemic encephalopathy, some correlation between magnetic resonance imaging findings and neurodevelopmental outcome was recognized. The patients with deep gray matter involvement on the initial magnetic resonance imaging had a poor prognosis, and the ones with normal magnetic resonance imaging findings had a favorable neurodevelopmental outcome. On the follow-up magnetic resonance imaging findings, encephalomalacia and periventricular leukomalacia were associated with poor neurodevelopmental outcome. In predicting the neurologic outcome at 4 years of age, magnetic resonance imaging findings of the neonatal period had the highest negative predictive value, whereas magnetic resonance imaging findings at 4 months of age and 4 years of age had the highest positive predictive value.

Magnetic resonance imaging of the posterior fossa in autism

The brainstem-cerebellar circuitry has been implicated in the pathophysiology of autism for several decades. Recent magnetic resonance imaging (MRI) studies of the posterior fossa have reported various abnormalities, the most noteworthy of which has been selective hypoplasia of the neocerebellar vermis. However, these initial MRI studies are limited by problems in both subject and control selection. The present study was undertaken to further investigate these MRI findings and the role of the cerebellum in autism, taking into consideration these methodologic issues. Eighteen high-functioning autistic subjects were recruited and matched with 18 normal controls on the basis of age, gender, IQ, race and socioeconomic status (SES). The midsagittal areas of the cerebellar vermis, vermal lobes, and the fourth ventricle were measured on 3 mm contiguous magnetic resonance images. Mean areas and standard deviations were comparable for all regions of interest and no statistically significant between-group differences were found. These negative findings argue against theories of autism based on gross structural abnormalities of the cerebellum. Previous reports of posterior fossa abnormalities may be related to technical and methodological factors, based on comparison of extant literature and recently available normative data.