Normal Magnetic Resonance Imaging Examination Research Articles

Plasmatic profiles of cytokines/chemokines, glial fibrillary acidic protein (GFAP) and MRI brain damage in neonates with hypoxic ischemic encephalopathy (HIE)

BackgroundPerinatal hypoxia triggers the release of cytokines and chemokines by neurons, astrocytes and microglia. In response to hypoxia–ischemia resting/ramified microglia proliferate and undergo activation, producing proinflammatory molecules. The brain damage extension seems to be related to both the severity of hypoxia and the balance between pro and anti-inflammatory response and can be explored with neuroimaging. AimsThe aim of this preliminary study was to explore possible relationships between plasma levels of inflammatory cytokines/chemokines and the severe brain damage detectable by Magnetic Resonance Imaging (MRI), performed during the hospitalization. MethodsIn 10 full terms neonates with hypoxic ischemic encephalopathy (HIE) undergoing therapeutic hypothermia (TH), divided into cases and controls, according to MRI results, we measured and compared the plasma levels of CCL2/MCP-1, CXCL8, GFAP, IFN y, IL-10, IL-18, IL-6, CCL3, ENOLASE2, GM-CSF, IL-1b, IL-12p70, IL-33, TNFα, collected at four different time points during TH (24, 25–48, 49–72 h of life, and 7–10 days from birth). Five of enrolled babies had pathological brain MRI (cases) and 5 had a normal MRI examination (controls). Cytokines were measured by Magnetic Luminex Assay. MRI images were classified according to Barkovich’s score. ResultsMean levels of all cytokines and molecules at time T1 were not significantly different in the two groups. Comparing samples paired by day of collection, the greatest differences between cases and controls were found at times T2 and T3, during TH. At T4, levels tended to get closer again (except for IL-6, IL10 and IL18). Infants with worse MRI showed higher plasmatic GFAP levels than those with normal MRI, while their IL-18 was lower. The mean levels of CCL3MIP1alpha, GMCSF, IL1BETA overlapped throughout the observation period in both groups. ConclusionIn a small number of infants with worse brain MRI, we found higher levels of GFAP and of IL-10 at T4 and a trend toward low IL-18 levels than in infants with normal MRI, considered early biomarker of brain damage and a predictor of adverse outcome, respectively. The greatest, although not significant, difference between the levels of molecules was found in cases and controls at time points T2 and T3, during TH.

Diagnostic value and prognostic significance of MRI findings in sudden sensorineural hearing loss.

PurposeWe evaluated the clinical significance of magnetic resonance imaging (MRI) findings and their prognostic value for initial hearing loss and recovery in patients with sudden sensorineural hearing loss (SSNHL).Materials and MethodsThis retrospective study included consecutive adult patients with unilateral SSNHL, contrast‐enhanced MRI and audiometric testing evaluated in our institution between 2005 and 2017. MRI reports, patient data, treatment, and audiometric tests were reviewed, with the relationship between MRI findings and hearing loss/recovery analyzed.ResultsOverall, 266 patients were included. Additional symptoms comprised tinnitus (114/266; 43%), vertigo (45/266; 17%), ear pain (26/266; 10%), and ear pressure (6/266; 2%). At least one cardiovascular risk factor (hypertension, diabetes, hypercholesterolemia, cardiopathy, and active smoking) existed in 167/266 (63%) patients. Corticosteroid treatment was followed by 198/266 (74%) patients while contraindications/refusal/compliance precluded treatment in 68/266(26%). Complete, partial or slight hearing recovery occurred in 167/266 (63%) patients. Three MRI patient groups were identified: a group with normal MRI examinations or incidentalomas (128/266; 48%), a group with peripheral auditory system (PAS) lesions (95/266; 36%), and a group with central nervous system (CNS) lesions (43/266; 16%). PAS lesions included lesions from the cochlea to the brain stem (e.g., schwannoma, meningioma, labyrinthitis, intracochlear hemorrhage, vestibulocochlear neuritis), whereas CNS lesions corresponded in 42/43(98%) of cases to leukoaraiosis and other vascular lesions (e.g., stroke, hemorrhage, aneurysm, venous sinus thrombosis, and cavernoma). Belonging to one of the three MRI groups did not influence the degree of initial hearing loss, affected frequencies or treatment, p > .05. Gender and cardiovascular risk factors did neither affect initial hearing loss nor recovery. However, age > 70 years negatively affected initial hearing loss in all frequencies, as well as recovery in all frequencies except 1000 Hz. Also, poor recovery of initial high‐frequency hearing loss (>1000 Hz) was significantly associated with CNS lesions.ConclusionAge > 70 years and CNS lesions depicted by MRI independently predicted poor auditory recovery, albeit in different frequencies.Lay SummaryIn patients with sudden hearing loss, older age (above 70 years) predicts poorer hearing recovery than in younger patients in most hearing frequencies. In addition, abnormalities of brain tissue revealed by MRI predict poorer hearing recovery at high frequencies.Level of EvidenceLevel III.

Correlation of Serum C-Peptide, Soluble Intercellular Adhesion Molecule-1, and NLRP3 Inflammasome-Related Inflammatory Factor Interleukin-1β after Brain Magnetic Resonance Imaging Examination with Cerebral Small Vessel Disease

Objective To explore the correlation of serum c-peptide, soluble intercellular adhesion molecule-1 (sICAM-1), and NLRP3 inflammasome-related inflammatory factor interleukin-1β (IL-1β) after brain magnetic resonance imaging (MRI) examination with cerebral small vessel disease (CSVD). Methods A total of 72 CSVD patients treated in our hospital from December 2018 to December 2019 were selected as the case group and another 72 patients who presented cerebrovascular risk factors but obtained normal brain MRI examination result in the same period were selected as the control group. The serum specimen of patients in the two groups were collected, their serum c-peptide levels were measured by radio immunoassay, and their serum sICAM-1 and NLRP3 inflammasome-related inflammatory factor IL-1β were measured by enzyme-linked immunosorbent assay (ELISA), so as to analyze the correlation between these indicators and CSVD. Results Compared with the control group, the level values of serum c-peptide, sICAM-1, and IL-1β were significantly higher in the case group (P < 0.001), with CSVD being the dependent variable, and age, smoking, uric acid, history of stroke, serum c-peptide, sICAM-1, and IL-1β being the independent variables. A logistic regression analysis was conducted, and the result showed that age, smoking, serum c-peptide, sICAM-1, and IL-1β were the risk factors for CSVD, and by drawing the ROC curves, it could be concluded that the area under sICAM-1 curve was larger than that of other single indicator. Conclusion Elevation of level values of serum c-peptide, sICAM-1, and NLRP3 inflammasome-related inflammatory factor IL-1β is correlative with CSVD, and age, smoking, serum c-peptide, sICAM-1, and IL-1β are the independent risk factors for CSVD.

Radiographer reporting of neurological magnetic resonance imaging examinations of the head and cervical spine: Findings of an accredited postgraduate programme

IntroductionTo analyse the objective structured examination (OSE) results of the first cohorts of radiographers (n = 13) who successfully completed an accredited postgraduate programme in clinical reporting of neurological magnetic resonance imaging (MRI) examinations of the head and cervical spine. MethodsForty MRI examinations were used in the OSE which included a range of abnormal cases (prevalence of abnormal examinations approximated 50%) and included: haemorrhage, infarction, demyelination disease, abscess, mass lesions (metastatic deposits, meningioma, glioma, astrocytoma); and disc disease, cord compression, stenosis, ligament rupture, syringomyelia appearances on patients referred from a range of referral sources. Normal variants and incidental findings were also included. True/false positive and negative fractions were used to mark the responses which were also scored for agreement with the previously agreed expected answers based on agreement between three consultant radiologists' reports. ResultsThe mean sensitivity, specificity and agreement rates for all head and cervical spine investigations (n = 520) combined were 98.86%, 98.08% and 88.37%, respectively. The highest scoring cases were cases which included astrocytoma, disc protrusion with cord compression and glioma. The most common errors were related to syringomyelia, ligament rupture and vertebral fracture. ConclusionsThese OSE results suggest that in an academic setting, and following an accredited postgraduate education programme, this group of radiographers has the ability to correctly identify normal MRI examinations of the head/cervical spine and are able to provide a report on the abnormal appearances to a high standard. Further work is required to confirm the clinical application of these findings.

Do we need gadolinium-based contrast medium for brain magnetic resonance imaging in children?

Brain imaging is the most common examination in pediatric magnetic resonance imaging (MRI), often combined with the use of a gadolinium-based contrast medium. The application of gadolinium-based contrast medium poses some risk. There is limited evidence of the benefits of contrast medium in pediatric brain imaging. To assess the diagnostic gain of contrast-enhanced sequences in brain MRI when the unenhanced sequences are normal. We retrospectively assessed 6,683 brain MR examinations using contrast medium in children younger than 16years in the pediatric radiology department of the University Hospital Leipzig to determine whether contrast-enhanced sequences delivered additional, clinically relevant information to pre-contrast sequences. All examinations were executed using a 1.5-T or a 3-T system. In 8 of 3,003 (95% confidence interval 0.12-0.52%) unenhanced normal brain examinations, a relevant additional finding was detected when contrast medium was administered. Contrast enhancement led to a change in diagnosis in only one of these cases. Children with a normal pre-contrast brain MRI rarely benefit from contrast medium application. Comparing these results to the risks and disadvantages of a routine gadolinium application, there is substantiated numerical evidence for avoiding routine administration of gadolinium in a pre-contrast normal MRI examination.

Role of MRI in Evaluation of Traumatic Ankle Injuries

Background: MR imaging has become the diagnostic modality of choice for the evaluation of traumatic ligamentous, tendinous injures of the ankle and occult bony trauma. This article reviews the current applications of MR imaging for the evaluation of most of these lesions. Ankle sprains are considered the most common lower limb injuries (incidence between 5 - 7 per 1000 persons/year in Europe), affecting more frequently young athletes; the most common mechanism of injury is represented by inversion of the foot (less frequently eversion). Aim of the Work: The aim of the current study is to emphasize the value of Magnetic Resonance Imaging (MRI) in evaluation of patients with ankle pain caused by traumatic injury. Patients and Methods: A descriptive study, conducted from March 2017 till June 2017. Sixty patients underwent MRI examination (patients with traumatic ankle pain) during this period. Twenty patients have normal MRI examination and not included in the study while forty patients have positive MRI findings. All patients were performed MRI in radiology department, Ain Shams University Hospital. The examination carried out after signing the informed consent by the patient himself or his guardian if the patient is incapacitated by any means. Results: According to the data collected from our study, we have 70 pathologies diagnosed by MRI after traumatic ankle injuries. - 17 (24.3%) of them were ligamentous injuries. - 16 (22.9%) were tendon injuries. - 14 (20%) were bone injuries [3 (21.43%) of them were fractures and 5 (35.71%) of them were osteochondral lesions and 6 (42.86%) of them were Bone contusions]. - 23 (32.8%) from the seventy pathology have joint effusion. Conclusion: MRI is modality of choice in evaluating ankle injuries due to its high soft tissue contrast resolution, and multi-planar capabilities. It provides a non-invasive tool for the diagnosis of Ankle injuries, which are often difficult to diagnose with alternative modalities. MRI is particularly advantageous for assessing soft tissue structures around the ankle such as tendons, ligaments, nerves, and fascia and for detecting occult bone injuries.

What is the pelvic lymph node normal size? Determination from normal MRI examinations.

There are few previous reports on maximal pelvic lymph node sizes and no data on normal mesorectal nodes. Therefore, the aim of the study was to estimate the normal size of pelvic lymph nodes and to determine the upper limits of the normal range. Pelvic magnetic resonance imaging (MRI) examinations were prospectively carried out using a Intera 1.5T magnet (Philips, the Netherlands), on 36 healthy volunteers (22 females, 14 males, mean age 25years). A balanced fast field echo (b-FFE) sequence was used with the following parameters: 3-mm-thick contiguous slice, matrix 512×512. Short axis diameters of pelvic and inguinal lymph nodes were measured in each anatomic territory (internal iliac, external iliac, common iliac, mesorectum and inguinal). After normalization of the measurements, the influences of age, gender, laterality and territory were evaluated. Upper limits (95th percentile) were then calculated. A total of 1147 lymph nodes were measured. Age, gender and side (right/left) had no significant influence on size. The upper limits of the normal range were, respectively, 5.3, 4.4, 6.3 and 3.9mm for the external and common iliac, internal iliac, inguinal and mesorectum nodes. This work presents maximal normal values for each pelvic area, and the values for mesorectum nodes are reported for the first time. The mesorectum nodes should be considered as abnormal when they are over 4mm in short diameter. For the other node areas, the upper limits of the normal range were, respectively, 6, 6, 5, 7mm for the external and common iliac, internal, iliac and inguinal nodes for the short axis.

Diagnosis of ligamentous and meniscal pathologies in patients with anterior cruciate ligament injury: comparison of magnetic resonance imaging and arthroscopic findings.

Magnetic resonance imaging (MRI) is routinely used to diagnose or support clinical diagnoses for meniscal or ligamentous injuries prior to offering patients arthroscopic treatment. However, the sensitivity of MRI for the detection of meniscal injury is not yet 100%. Sportsmen have occasionally returned to play with undiagnosed meniscal lesions on the basis of a normal MRI examination. This study was designed to assess the diagnostic parameters of MRI in patients with acute anterior cruciate ligament (ACL) injury. MRI and arthroscopic findings of 320 patients with acute ACL injury were included in this retrospective review. Patients belonged to a single surgeon from a high volume tertiary healthcare institution. All patients had either a MRI or an arthroscopic diagnosis of an acute ACL injury of one knee or both. All patients underwent therapeutic arthroscopy by the senior author routinely as part of arthroscopy-aided ACL reconstruction. Arthroscopic findings were the diagnostic reference based on which the positive predictive value (PPV), negative predictive value (NPV), sensitivity, specificity and concordance strength of association of MRI were calculated for ACL, posterior cruciate ligament (PCL), medial meniscus (MM) and lateral meniscus (LM) injuries. MRI was most accurate in diagnosing cruciate ligament injuries with a PPV approaching 100%. The PPV of MRI in diagnosing meniscal injuries was approximately 60%. MRI was almost 100% sensitive and specific in diagnosing ACL injuries and 82% sensitive and 100% specific in diagnosing PCL injuries. Conversely, MRI was 77% sensitive and 90% specific in diagnosing MM injuries; and 57% sensitive and 95% specific in diagnosing LM injuries. MRI remains the gold standard for diagnosing soft tissue injuries of the knee. However, there is a false positive rate ranging from 6% to 11% for meniscal tears.

MRI FINDINGS IN THE SHOULDER OF COMPLETELY ASYMPTOMATIC ADOLESCENT ELITE TENNIS PLAYERS

BackgroundShoulder pathology in adult tennis players including rotator cuff pathology is well known. However, early adaptations have not previously been studied in the adolescent elite tennis players.ObjectivesTo describe magnetic resonance...

MRI assessment of local acute radiation syndrome

To describe local acute radiation syndrome and its radiological imaging characteristics. We performed a retrospective study of patients who had suffered skin and deeper radiation damage who were investigated by magnetic resonance imaging (MRI). We compared the clinical findings, C-reactive protein (CRP) levels and MRI results. A total of 22 MRI examinations were performed between 2005 and 2010 in 7 patients; 6 patients had increased CRP levels and MRI abnormalities. They were treated by surgery and local cellular therapy. One patient had no CRP or MRI abnormalities, and had a spontaneous good outcome. Eighteen abnormal MR examinations demonstrated high STIR signal and/or abnormal enhancement in the dermis and muscle tissues. Three MRI examinations demonstrated skeletal abnormalities, consistent with radionecrosis. The four normal MRI examinations were associated only with minor clinical manifestations such as pain and pigmentation disorders. MRI seems to be a useful and promising imaging investigation in radiation burns management i.e. initial lesion evaluation, treatment evaluation and complication diagnosis. MRI findings correlated perfectly with clinical stage and no false negative examinations were obtained. In particular, the association between normal MRI and low CRP level seems to be related to good outcome without specific treatment. Local acute radiation syndrome (radioepidermitis) mainly affects the skin and superficial tissues. MRI findings correspond with clinical stage (with a strong negative predictive value). MRI outperformed X-ray examination for the diagnosis of bone radionecrosis. Diffusion-weighted imaging shows low ADC in bone and soft tissue necrosis. Perfusion sequence allows assessment of tissue microcirculation impairment.

Cognitive Dysfunction Occurs In Children with Sickle Cell Anemia without Cerebral Ischemic Insult or Vasculopathy

Abstract 1076▪▪This icon denotes a clinically relevant abstract Background:Sickle cell anemia (SCA) has been associated with impairments in general cognitive functioning as measured by IQ scores and other neurocognitive measures. Children with SCA and overt stroke are the most affected, but those with silent infarcts (SI) on brain magnetic resonance imaging (MRI) also have cognitive impairment. Transcranial doppler ultrasonography (TCD) screening has allowed identification of individuals at high risk for stroke, in whom institution of prophylactic transfusion therapy produces a dramatic reduction in the incidence of primary stroke. Elevated TCD velocities have been reported to predict neurocognitive impairment in patients with SCA. We hypothesize that children with SCA with normal TCD velocities and no overt stroke or SI on brain MRI will have normal cognitive performance when compared with normal-matched controls. We investigated the academic achievement and cognitive function among children with SCA with normal brain MRI and normal TCD velocities, and compared their results with normal age and race matched controls. Methods:School age children with SCA who had normal MRI and TCD exams were evaluated. Controls (classmates and siblings) were matched for race, age, and social-economic status. SCA patients receiving chronic transfusion therapy or with a history of prior overt stroke were not eligible. All participants were followed at Instituto Estadual de Hematologia Arthur de Siqueira Cavalcanti (HEMORIO). All patients and controls underwent MRI examination (to document the absence of stroke and SI) and cognitive testing. In addition, SCA subjects underwent TCD testing and had hematologic laboratory testing. SCA subjects were not experiencing pain or any other complication during study evaluations. The WISC-III was obtained as a measure of intellectual function, and achievement scores in reading, writing, and arithmetic were used to evaluate school performance. Comparisons among patients and controls were made using the Mann-Whitney test. This study was approved by the HEMORIO Ethics committee and all participants signed informed consent. Results:SCA patients had significantly lower total IQ and academic achievement than healthy controls (Table).Table:Cognitive function among HbSS and healthy controls.VariableHbSS with normal MRI and TCDNormal Controlsp-value# children6041–Median Age (range) (years)10.3 (8–13)10 (8–13)–Gender (males/females)31/2925/16–Median TCD velocity (range) (cm/sec)120 (80–160)N/A–Mean Hb (±1SD) (mg/dL)8.4 (1.16)N/A–Median total IQ score931000.023Median Verbal IQ score94.2899.890.153Median Executive IQ score90.9196.500.11Median Reading achievement score44560.002Median Writing achievement score16220.02Median Arithmetic achievement score11150.011 Discussion:This is the first report showing cognitive dysfunction in children with SCA with both normal MRI and TCD examination. Early neurocognitive deficits are known to occur in children with SCA. In general, a patient with SCA in Brazil has a low socioeconomic status, low educational level, and poor access to health services, placing these children at higher risk of neurocognitive complications from the disease. Our study shows that children with SCA perform worse on measures of key cognitive function when compared with healthy matched controls, even without evidence of elevated velocities in the main cerebral arterial vessels or radiological insult to the brain. There was a significant difference in total IQ and school achievement among SCA patients and controls; however this was not true for verbal or executive IQ, suggesting that the cognitive compromise in this population is global. Cognitive dysfunction may occur long before lesions are observed on the MRI (ischemic insult) or on the TCD (vasculopathy), underscoring the need for preemptive screening and treatment of cognitive dysfunction in children with SCA. Disclosures:Off Label Use: Hydroxyurea for prevention of neuropsychological changes in SCD.

MRI findings in the lumbar spines of asymptomatic, adolescent, elite tennis players

Objective:To describe magnetic resonance imaging (MRI) findings in the lumbar spine in asymptomatic elite adolescent tennis players, to serve as the baseline for a future prospective longitudinal cohort study.Design:Observational study.Setting:Institutional,...

Contribution of Proton Magnetic Resonance Spectroscopy to the Evaluation of Children with Unexplained Developmental Delay

Developmental delay (DD) in children is a common socioeconomic problem with a prevalence of 1-2%. The cause of DD in children is often unknown, and magnetic resonance imaging plays an important role in evaluating children with DD, estimating long-term prognosis, and guiding therapeutic options. The aim of our study on children with DD was to elucidate 1) whether magnetic resonance spectroscopy (MRS) reveals abnormalities in cerebral metabolism and 2) whether there is a correlation between the cognitive performance and the concentration of brain metabolites, especially N-acetylaspartate (NAA), named in the literature a neuronal marker. Using proton MRS of deep gray and central white matter, we measured concentrations of brain metabolites in 48 children, who were aged 1 mo to 13 y and had unexplained DD [developmental quotient (DQ) between <50 and 85] and normal magnetic resonance imaging examinations, and compared them with those of 23 age-matched normal control children. Children with DD were divided into three groups: mild (DQ 76-85), moderate (DQ 51-75), and severe (DQ <50). We found no significant differences in metabolite concentrations, neither among the three groups of children with DD nor between patients and age-matched normal control children. Independent of the degree of mental retardation, the NAA concentrations of handicapped patients and normal children were comparable. We conclude that 1) brain metabolites, especially NAA, in children with unexplained DD are within normal limits, and 2) in most cases, proton MRS adds little information concerning cause of unexplained DD.

Acute Quadriceps Muscle Strains

Background There has been no research examining the magnetic resonance imaging findings, and in turn the prognosis, for a series of acute quadriceps muscle strains. Hypothesis The magnetic resonance imaging findings of acute quadriceps muscle strain injuries are helpful in predicting their prognosis. Study Design Causal-comparative study. Method Forty professional players of Australian Rules football were followed over 3 years. Magnetic resonance imaging examinations were performed within 24 to 72 hours of muscle-strain injury. Imaging features of muscle strain injury included the anatomical location, size (cross-sectional area and length), and site (proximal, middle, or distal). The time from injury to return to full training was termed the rehabilitation interval. Results 25 clinical quadriceps muscle strain injuries occurred, with 15 cases involving the rectus femoris. The rectus femoris injuries could be further categorized into cases with straining about the central tendon (n = 7, mean rehabilitation interval = 26.9 days) or cases with straining in the periphery (n = 8, mean rehabilitation interval = 9.2 days). Six cases involved one of the vastus muscles (mean rehabilitation interval = 4.4 days). Three players had normal magnetic resonance imaging examinations (mean rehabilitation interval = 5.7 days). Conclusions The rectus femoris–central tendon injury is the red flag diagnosis associated with a significantly longer rehabilitation interval. Clinical Relevance Magnetic resonance imaging is helpful in predicting the prognosis for acute quadriceps strains.

Comparison of knee magnetic resonance imaging findings in patients referred by orthopaedic surgeons versus nonorthopaedic practitioners

Purpose: To compare the percentages of normal magnetic resonance imaging (MRI) examination results and clinically significant knee abnormalities in patients referred for MRI of the knee by orthopaedic surgery residents and staff with those of patients referred by nonorthopaedic practitioners. Type of Study: Retrospective review of MRI findings. Methods: MRI reports of 754 patients (454 men and 300 women) were retrospectively reviewed; 373 patients were referred from the Department of Orthopaedic Surgery and 381 patients were referred from nonorthopaedic practitioners. The number of normal examination results, meniscal and ligament tears, chondral abnormalities, and Baker’s cysts was tabulated and analyzed using a χ-square injury analysis. Results: The rate of normal results for nonorthopaedic practitioners was 33.9% (129 of 381) compared with 15.3% (57 of 373) for orthopaedic surgeons (P <.001). Nonorthopaedic surgeons referred 69.4% (129 of 186) of the patients who had normal examination results. The positive finding for a lateral meniscus tear was 29.2% (109 of 373) for orthopaedic surgeons compared with 19.1% (73 of 381) for nonorthopaedic practitioners, which was statistically significant (P =.002) in regard to the distribution of injuries. No difference was found in other abnormalities assessed. Conclusions: Patients referred by nonorthopaedic practitioners had significantly more normal knee MRI examination results than did those referred by orthopaedic surgeons.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 18, No 2 (February), 2002: pp 201–205

MRI in routine breast cancer follow-up: Correlation with clinical outcome

AIM: Magnetic resonance imaging (MRI) of the breast has been shown to be useful as an additional imaging test in patients suspected of having recurrent disease, when clinical examination or mammography are equivocal. This study examines the utility of MRI as a routine test in the follow-up of treated breast cancer patients without equivocal clinical or imaging findings. MATERIALS AND METHODS: Contrast-enhanced breast MRI was performed as part of routine breast cancer follow-up in 26 patients with equivocal clinical or mammographic findings and 33 control patients in whom clinical and imaging findings were consistent with post-treatment changes only. Clinical outcome was assessed at 3 years post MRI. RESULTS: Four patients with equivocal clinical or mammographic findings had abnormal MRI: all MRI abnormalities were subsequently shown to represent benign disease. None of the equivocal group developed local recurrence, although two of 26 developed distant metastases. One of the control group had unsuspected distant metastases detected by MRI: the other 32 patients had no significant abnormality on MRI. Three patients subsequently developed local tumour recurrence. CONCLUSION: A single normal breast MRI examination during follow-up is a poor predictor of subsequent local recurrence.

Development and clinical application of kinematic MRI of the patellofemoral joint using an extremity MR system.

Kinematic magnetic resonance imaging (MRI) of the patellofemoral joint provides diagnostic information pertaining to patellar alignment and tracking during the earliest increments of joint flexion, when abnormalities that affect this joint are the most apparent. Recently, a low-field strength (0.2 Tesla) dedicated extremity MR system has been designed, such that only the body part that is being imaged is placed inside of the magnet bore. The purpose of this investigation was to develop a kinematic MRI technique for the patellofemoral joint using the extremity MR system and to apply this procedure in the clinical setting. An incremental, passive positioning kinematic MRI technique was developed for the patellofemoral joint that involved obtaining three different axial section locations with the patellofemoral joint extended and then imaging these same section locations repeatedly as the patellofemoral joint was flexed in four increments up to 36 degrees of flexion. MR images were obtained using a T1-weighted spin echo sequence. Five (10 PFJ) asymptomatic volunteers and nine patients (9 PFJ) with patellofemoral joint symptoms were studied. Volunteers had normal kinematic MRI examinations. Seven patients had lateral subluxation, and two patients had excessive lateral pressure syndrome. Two patients with lateral subluxation seen on their kinematic MRI studies had Merchant views (x-rays obtained at 45 degrees) that showed "normal" patellar alignment, illustrating the importance of imaging the patellofemoral joint at 30 degrees or less. A kinematic MRI technique was successfully developed for the low-field extremity MR system and utilized for clinical applications. This procedure may be used to determine the presence and severity of patellar malalignment and abnormal tracking patterns.

Cerebral magnetic resonance imaging (MRI) of very low birth weight infants at one year of corrected age.

Cerebral MRI was performed at 1.5 T in 27 infants with birth weight below 1500 grams at 1 year of corrected age. The images were compared to those reported on normal development at the same age. On T1 weighted images, 20 (74.1%) of the 27 infants showed myelin deposition different from what has been reported to be normal. Areas most affected were the central occipital white matter and the centrum semiovale. Both correspond to "watershed areas" known to be at risk for periventricular leukomalacia in preterm infants. T2-weighted images showed delayed myelination in the same areas as described for T1. In addition, two infants showed delayed myelination in the central occipital white matter and one in the centrum semiovale. Patchy focal abnormalities involving the white matter were seen in seven (25.9%) infants. Mild cerebral atrophy, mainly of the cortex was found in 10 (37.0%) infants. Irregular shape of the lateral ventricles, especially of the occipital horns was present in 12 infants (44.4%). 11 of these infants also had deviating changes in myelination. Only 2 infants (7.4%) had a normal MRI examination. Follow-up MRI examinations are needed to determine whether the high percentage of changes in myelination represent delayed development or brain damage in preterm infants.

Physiologic abnormalities in the paranasal sinuses during experimental rhinovirus colds

Six (18%) of 34 healthy, asymptomatic young adults had mucosal thickening or fluid in the paranasal sinuses on screening magnetic resonance imaging (MRI) examination. When 19 of these subjects were challenged with rhinovirus, 18 became infected. Twelve of the 18 infected subjects had technically satisfactory serial MRI examinations, and four (33%) of these developed MRI abnormalities of the ethmoid or antral sinuses that were temporally associated with the acute infection. The mean total nasal secretion weights were 22 gm/5 days in the four subjects whose MRI abnormalities were associated with the acute infection compared with 5.5 gm/5 days in the eight subjects who had normal MRI examinations during the acute infection ( p = 0.06). Abnormalities of the paranasal sinuses, which were associated with increased volumes of nasal secretion, were detected by MRI examination during rhinovirus infection. These abnormalities may have a role in the pathogenesis of acute sinusitis associated with colds.