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Purpose: To determine whether spinal cord atrophy differs among disease subtypes in multiple sclerosis (MS) and whether it offers diagnostic and clinical correlative information beyond that provided by other magnetic resonance (MR) imaging markers., Materials and Methods: The institutional review board approved the study; all subjects gave written informed consent. Upper cervical cord cross-sectional area (UCCA), brain and spinal cord lesion loads, and brain atrophy were measured in 440 patients with MS (311 with relapsing-remitting [RR] MS, 92 with secondary-progressive [SP] MS, and 37 with primary-progressive [PP] MS) studied in two centers. Disability was scored with the Expanded Disability Status Scale (EDSS), the timed 25-foot walk test (TWT), and the nine-hole peg test. UCCA was compared between groups with the Mann-Whitney U test. Correlations were assessed with the Spearman ρ test. Multivariate associations between UCCA and clinical and other MR imaging parameters, including number of hypointense brain lesions on T1-weighted MR images, presence of diffuse abnormalities, and number of involved segments in the spinal cord, were assessed by using multiple linear regression, adjusted for study center site., Results: The UCCA in patients with SP MS (median, 79 mm(2); interquartile range, 72.4-84.9 mm(2)) and PP MS (median, 77.3 mm(2); interquartile range, 69-82.5 mm(2)) was significantly smaller (P < .001) than that in patients with RR MS (median, 84 mm(2); interquartile range, 78.7-89.3 mm(2)). UCCA was inversely correlated with EDSS score, TWT, and nine-hole peg test findings (ρ ≤ -0.29, P < .001 for all comparisons). UCCA, number of hypointense brain lesions on T1-weighted MR images, presence of diffuse abnormalities, and number of involved segments in the spinal cord were found to be significant explanatory factors for clinical disability (R(2) = 0.564). The UCCA and the number of hypointense brain lesions on T1-weighted images were the strongest MR imaging parameters for explaining physical disability, as measured with the EDSS., Conclusion: Spinal cord abnormalities have a strong effect on clinical disability in MS. MR imaging-derived UCCA was found to be the most significant spinal cord parameter for explaining EDSS score., (RSNA, 2013)

Purpose: To examine the benefits of using near-isotropic single-slab three-dimensional (3D) magnetic resonance (MR) imaging for the creation of subtraction images and to evaluate their performance in the detection of active multiple sclerosis (MS) brain lesions in comparison with two-dimensional (2D) subtraction images., Materials and Methods: The study protocol was approved by the local ethics review board and all subjects gave written informed consent before investigation. Three-dimensional MR sequences, including double inversion-recovery, fluid-attenuated inversion recovery, T2-weighted, and T1-weighted magnetization-prepared rapid acquisition gradient-echo (MP-RAGE), and corresponding 2D sequences were performed twice in 14 patients (eight women, six men; mean age, 37.6 years) with MS and nine age-matched healthy control subjects (three women, six men; mean age, 31.7 years). Active lesions were scored by two independent raters, followed by a consensus reading. Lesion counts were evaluated by using negative binomial regression; interrater agreement was evaluated by using intraclass correlation coefficient., Results: Three-dimensional subtraction images had less residual misregistration and flow artifacts and depicted higher numbers of active lesions with greater interobserver agreement compared with 2D subtraction images. Among the 3D sequences, MP-RAGE subtraction imaging enabled detection of a significantly higher mean number of positive active MS lesions compared with 2D subtraction imaging (2.8 versus 1.7, P = .012), particularly infratentorial lesions (0.6 vs 0.1, P < .05), and a substantially higher (nonsignificant) mean number of small (<3 mm) lesions (0.6 vs 0.1, P > .05)., Conclusion: Three-dimensional subtraction imaging, after image registration, produced better image quality, leading to increased detection of active MS lesions with greater interobserver agreement in comparison with 2D subtraction imaging; 3D MP-RAGE subtraction imaging represents a promising technique to increase sensitivity in ascertaining lesion dissemination in time and increase the power of MR imaging metrics for the evaluation of treatment effects in clinical trials., (RSNA, 2010)

Purpose: To explore the applicability of subtraction magnetic resonance (MR) images to (a) detect active multiple sclerosis (MS) lesions, (b) directly quantify lesion load change, and (c) detect treatment effects (distinguish treatment arms) in a placebo-controlled multicenter clinical trial by comparing the subtraction scheme with a conventional pair-wise comparison of nonregistered MR images., Materials and Methods: Forty-six pairs of MR studies in 40 patients (31 women; mean age, 31.9 years) from a multicenter clinical trial were used. The clinical trial was approved by local ethics review boards, and all subjects gave written informed consent. Active MS lesions were scored by two independent raters, and lesion load measurements were conducted by using semiautomated software. Lesion counts were evaluated by using the Wilcoxon signed rank test, interrater agreement was evaluated by using the intraclass correlation coefficient (ICC), and treatment (interferon beta-1b) effect was evaluated by using the Mann-Whitney U test., Results: When subtraction images were used, there was a 1.7-fold increase in the detection of positive active lesions, as compared with native image pairs, and significantly greater interobserver agreement (ICC = 0.98 vs 0.91, P < .001). Subtraction images also allowed direct quantification of positive disease activity, a measure that provided sufficient power to distinguish treatment arms (P = .012) compared with the standard measurement of total lesion load change on native images (P = .455)., Conclusion: MR image subtraction enabled detection of higher numbers of active MS lesions with greater interobserver agreement and exhibited increased power to distinguish treatment arms, as compared with a conventional pair-wise comparison of nonregistered MR images.

Purpose: To establish the supplemental value of diffusion-weighted (DW) magnetic resonance (MR) imaging beyond conventional MR to predict clinical outcome after neonatal hypoxic ischemia (HI) at 2 years of age., Materials and Methods: Forty-six infants with neonatal HI were enrolled in this prospective study, after approval by the local ethical committee and informed consent of the parents. Neonatal MR imaging ranged from 1 to 45 days after birth. Apparent diffusion coefficient (ADC) was measured in 14 brain regions. DW and conventional images were qualitatively scored for abnormalities, resulting in cumulative scores and patterns of damage. Surviving infants were scored for motor outcome at the age of 2 years, and outcome was classified as poor if the motor score was less than 70 or in case of death. Analyses were performed for the whole group, with additional analyses for the early (0-4 days after birth) and late (>4 days after birth) imaging groups., Results: Twenty-five infants had a good outcome and 21 had a poor outcome. Only in the early imaging group, the infants with poor outcome had significantly lowered ADC values in several brain areas, with the posterior limb of the internal capsule being the most predictive (Wald score = 5.7; P = .017). Cumulative scores of DW imaging were the best predictor of poor motor outcome at the age of 2 years (Wald score = 7.2, P < .01). The basal ganglia and central cortex and the diffuse pattern of brain damage were highly associated with poor outcome (Fisher exact test = 29.8; P < .001)., Conclusion: In neonatal HI, DW imaging is a useful additional MR technique to predict the motor outcome at 2 years. Local ADC values had a limited value. Recognition of the patterns of brain damage with DW and conventional MR imaging can be used as a diagnostic tool in neonatal HI., ((c) RSNA, 2008.)

Purpose: To evaluate eye size retrospectively by using magnetic resonance (MR) imaging to measure axial length (AL), equatorial diameter (ED), and eye volume (EV) in patients with retinoblastoma and to evaluate the possible effect of retinoblastoma on eye size., Materials and Methods: Local ethics committee approval was obtained with waiver of informed consent. MR images of 100 patients with retinoblastoma (50 girls, 50 boys; mean age, 19 months; age range, 9 days to 68 months) were scored by one observer (AL, ED, EV, and tumor volume measurements), with a second observer reviewing all measurements. Normal eyes of patients with unilateral retinoblastoma served as controls. Interobserver measurement agreement was evaluated in a random subset of 50 eyes with use of intraclass correlation coefficients. Linear mixed model analysis was used with adjustments for age, laterality, and sex., Results: Interobserver agreement was good (intraclass correlation coefficients >or= 0.89). Eyes with retinoblastoma had significantly shorter ALs (95% confidence interval [CI]: -0.57 mm, -0.16 mm; P=.001) and EDs (95% CI: -1.01 mm, -0.66 mm; P<.001) and significantly smaller EVs (95% CI: -336 mm(3), -151 mm(3); P<.001) than normal eyes. Within patients, a significant negative relationship was found between tumor volume and EV (P<.001)., Conclusion: MR imaging measurements of AL, ED, and EV were significantly smaller in eyes with retinoblastoma than in normal eyes. In addition, in patients with retinoblastoma, the larger the tumor volume, the smaller the eye., ((c) RSNA, 2007.)

Purpose: To retrospectively evaluate the prognostic significance of magnetic resonance (MR) imaging-determined tumor parameters, especially the presence of cartilage invasion, regarding local control of glottic squamous cell carcinoma treated with radiation therapy (RT) alone., Materials and Methods: The study was performed with the approval of our institutional review board; direct patient consent was waived. Pretreatment MR images of 118 patients aged 41-86 years (110 men, eight women) with glottic carcinoma treated with RT alone were reviewed for tumor involvement of specific laryngeal anatomic subsites (including laryngeal cartilage), tumor volume, and extralaryngeal tumor spread; these findings were compared with local control. Local control was defined as absence of a recurrence at the primary site for 2 years. Statistical significance of differences between curves for local control estimated with the Kaplan-Meier method was tested with log-rank test., Results: Results of univariate analysis showed all MR imaging-determined parameters to be significant predictors of local control rate, compared with clinical parameters where T classification and vocal cord mobility were the only significant parameters associated with local control. Multivariate analysis (Cox regression model) of clinical and radiologic parameters revealed that hypopharyngeal extension (P=.04) and intermediate T2 signal intensity (SI) in cartilage similar to tumor SI (P<.001) were independent prognostic factors with regard to local control., Conclusion: Intermediate T2 SI in cartilage, which may suggest cartilage invasion, and hypopharyngeal extension of tumor, predict greater likelihood of local failure, whereas high T2 SI, which may suggest inflammatory tissue in cartilage, predicts lower likelihood of local failure., ((c) RSNA, 2007.)

Purpose: To prospectively investigate whether T1 changes in normal-appearing white matter (WM) and normal-appearing gray matter (GM) in multiple sclerosis (MS) are global or regional and their relationship to disease type., Materials and Methods: The institutional ethics review board approved study; written informed consent was obtained. Whole-brain T1 maps were obtained in 67 patients with MS and 24 healthy control subjects with three-dimensional fast low-angle shot flip angle-array method, with correction for B(1) imperfections. Analysis of variance was performed on T1 histogram parameters of global normal-appearing WM and GM. Regional mean T1 values were analyzed with a multilevel approach. Multiple linear regression analysis was performed to investigate associations with clinical disability and overall atrophy. For patients, T2 lesion load was determined., Results: T1 histograms of normal-appearing WM had significantly higher peak positions for patients with MS (792 msec +/- 36 in secondary progressive [SP] MS) than for control subjects (746 msec +/- 23) and were significantly broader and lower (all P < .001). Histograms for cortical normal-appearing GM were significantly shifted (peak positions, 1263 msec +/- 44 in control subjects and 1355 msec +/- 62 in patients with SP MS) (P < .001). Histogram peak positions were significantly higher in SP MS than in relapsing-remitting (RR) and primary progressive MS (P < .05). In SP disease, at least 31% of normal-appearing WM and 20% of cortical normal-appearing GM were affected. In MS, T1 was significantly elevated in all normal-appearing WM and cortical normal-appearing GM regions (all P < .01) but was elevated only in the thalamus in deep GM (P < .05). Cortical T1 histogram peak position was associated with clinical disability; T2 lesion load was not., Conclusion: Results suggest that a global disease process affects large parts of both normal-appearing WM and GM in MS and effects are worse for SP MS than for RR MS., ((c) RSNA, 2006.)

Purpose: To assess diagnostic accuracy of preoperatively performed magnetic resonance (MR) imaging for detection of tumor extent in a large patient population with histopathologically proved retinoblastoma., Materials and Methods: Local ethics committee approval and informed consent were not required for retrospective review of patients' images and records. Fifty-eight eyes in 28 girls (mean age, 21 months; range, 2-59 months) and 28 boys (mean age, 24 months; range, 2-76 months) with retinoblastoma were retrospectively reviewed by one radiologist on unenhanced T1-weighted, dual-echo T2-weighted, and gadolinium-enhanced T1-weighted MR images. MR imaging parameters such as growth pattern, anterior chamber hyperintensity, and involvement of choroid, ciliary body, optic nerve, sclera, orbital fat, and pineal gland were determined. Tumor volume was measured and correlated to metastatic risk factors. Imaging and pathologic findings were compared. Statistical analysis was performed by using logistic regression with log likelihood ratio chi(2) test or Fisher exact test., Results: Choroidal invasion was suspected with MR imaging in 21 eyes; findings were false-positive in 13 eyes and false-negative in three (73% sensitivity, 72% specificity, 72% accuracy). Anterior chamber hyperintensity on T1-weighted MR images obtained after contrast agent administration correlated well with clinical presence of reactive neovascular processes. MR imaging findings were true-positive in 21 of 32 eyes with proved prelaminar optic nerve invasion (66% sensitivity) and false-positive in one (96% specificity, 79% accuracy). Postlaminar optic nerve invasion was correctly detected in two eyes; in two other eyes, this metastatic risk factor was missed (50% sensitivity, 100% specificity, 97% accuracy). Scleral and extrascleral tumor invasion were correctly excluded in all eyes. Tumor volume was statistically associated with prelaminar optic nerve invasion (P = .001) and choroidal invasion (P = .031)., Conclusion: MR imaging is accurate for tumor staging and detection of metastatic risk factors; detection of intraocular tumor infiltration remains difficult. Tumor volume, measured with MR imaging, was associated with prelaminar optic nerve and choroidal involvement., ((c) RSNA, 2005.)

Purpose: To retrospectively assess the prognostic meaning of tumor characteristics depicted on pretreatment magnetic resonance (MR) images for local outcome in supraglottic squamous cell carcinoma treated with definitive radiation therapy., Materials and Methods: Pretreatment MR images acquired in 84 patients with supraglottic carcinoma treated with curative radiation therapy were reviewed for tumor involvement of laryngeal sites including glottis, subglottis, pre-epiglottic space, laryngeal cartilages, and hypopharynx, and for extralaryngeal extension. The volume of each tumor was estimated, and mean tumor volume was calculated for the group of tumors in each T staging category., Results: Results of univariate analysis showed MR imaging-determined primary tumor volume (P =.03), involvement of pre-epiglottic space (P =.008), abnormal signal intensity in thyroid cartilage (P =.04), and extralaryngeal extension beyond thyroid and/or cricoid cartilage (P =.02) to be significant predictors of local control rate. Results of multivariate analysis with the Cox regression model confirmed statistical significance for invasion of pre-epiglottic space (P =.004) and for abnormal signal intensities in thyroid cartilage adjacent to the anterior commissure (P =.04) and in cricoid cartilage (P =.01). Five-year local control rates were calculated from the regression coefficients of three independent MR imaging prognostic factors, and three prognostic groups were identified on the basis of these control rates. The 5-year local control rate in the high-risk group was 35%, significantly lower than the rates in the intermediate- and low-risk groups (60% and 89%, respectively; P =.002)., Conclusion: MR imaging-determined pre-epiglottic space involvement and abnormal signal intensities in the thyroid cartilage adjacent to the anterior commissure and/or the cricoid cartilage are strong predictors of local outcome in supraglottic carcinoma treated with definitive radiation therapy., (Copyright RSNA, 2004)