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Radiogenomics can potentially be used to predict molecular information from MR images in retinoblastoma.

MYCN-amplified RB1wild-type retinoblastoma has distinct features compared with RB1pathogenic variant–driven retinoblastoma at MRI, including tumors in a peripheral (anterior) location with plaque or pleomorphic shape, irregular margins, tumor-retinal folding, and peritumoral blood.

Intraocular tumor size is strongly associated with postlaminar optic nerve invasion and moderately associated with massive choroidal invasion.

BACKGROUND Diffuse abnormalities in the white matter (WM), ie, the so-called diffusely abnormal WM (DAWM), as observed on magnetic resonance imaging (MRI), may contribute to the development of clinical disability in multiple sclerosis (MS). Underlying pathologic and MRI characteristics of DAWM are largely unknown. OBJECTIVES To explore and describe the histopathologic and radiologic characteristics of DAWM in chronic MS. DESIGN An MRI and histopathologic postmortem correlative study. METHODS We analyzed 17 formalin-fixed hemispheric brain slices from 10 patients with chronic MS using histopathologic analysis and qualitative and quantitative MRI. A region-of-interest approach was applied to compare radiologically defined DAWM, normal-appearing WM, and focal WM lesions and to correlate quantitative MRI measures with histopathologic findings. MAIN OUTCOME MEASURES The DAWM consisted of extensive axonal loss, decreased myelin density, and chronic fibrillary gliosis, all of which were substantially abnormal compared with normal-appearing WM and significantly different from focal WM lesion pathology. Increased T1- and T2-relaxation times and decreased fractional anisotropy values were found in DAWM regions of interest, in association with extensive axonal loss and reduced myelin density. Increased T1- and T2-relaxation times were associated with chronic gliosis. CONCLUSIONS This study classifies DAWM in chronic MS as an abnormality that is different from normal-appearing WM and focal WM lesions, most likely resulting from the cumulative effects of ongoing inflammation and axonal pathology. As such, DAWM is likely to substantially contribute to disease progression and may prove to be an important new disease marker in clinical trials focusing on the neurodegenerative aspects of MS.Arch Neurol. 2009;66(5):601-609--

Objectives/Hypothesis:The detection of distant metastases during screening influences the choice of treatment in patients with head and neck squamous cell carcinoma. A previous study in the authors' institution showed that chest computed tomography (CT) scan was the most important screening technique. Different clinical risk factors in patients with head and neck squamous cell carcinoma for the development of distant metastases were identified.

Objective: Brain tumors are frequently accompanied by abnormal low frequency magnetic activity (ALFMA). The prevalence and clinical meaning of ALFMA are not well known, although a relation with epileptic brain tissue has been suggested. We studied the prevalence, characteristics and clinical correlates of ALFMA in 20 patients with brain tumors. Methods: In 20 patients with clinical seizures due to a supratentorial tumor, MEG was performed, followed by MR imaging. MEG signals were band pass-filtered (1-4 Hz); the sources of this activity were localized and projected onto the MRI of the patient. Results: Peritumoral ALFMA could be detected in 13 of 20 patients. A pattern of ALFMA distribution around the tumor could be recognized. In eight cases ALFMA also appeared to be localized within the tumor. In three cases ALFMA was also detected in peritumoral white matter. Conclusions: Automatic detection of abnormal delta-activity in patients with a brain tumor and seizures can be performed in a clinical setting. When detected, ALFMA is mostly present in circumscribed regions around the tumor. Presence of ALFMA within the tumor might be an important warning signal for the neurosurgeon that the tumor area comprises functional brain tissue.

The objective of this study was to assess patency of the internal jugular vein following modified radical or selective neck dissection and microvascular flap reconstruction by power Doppler ultrasound and its impact on free flap survival. In 23 patients who underwent selective or modified radical neck dissection and microvascular flap reconstruction the patency of the internal jugular vein was examined by power Doppler ultrasound on the first post-operative day and after follow-up of at least four months. On the first post-operative day in one patient partial thrombosis was found, while in the other 22 patients the internal jugular vein was normal patent. During follow-up in 17 (74 per cent) patients a normal patent internal jugular vein was found, while partial and complete thrombosis were found in three (13 per cent) patients each. On the first post-operative day 22 of the 23 (96 per cent) free flap veins were visualized. There was no free flap loss during follow-up. Power Doppler ultrasound is a valuable diagnostic technique for determination of internal jugular vein patency and may be useful as screening method or in case of clinical suspicion of thrombosis to determine internal jugular vein patency. Late internal jugular vein thrombosis may probably not effect free flap survival due to neovascularization.

In this study, we compared direct postmortem in situ (whole‐corpse) sagittal spinal cord magnetic resonance imaging (1.5T) of 7 multiple sclerosis cases with targeted high‐resolution in vitro axial magnetic resonance imaging (4.7T) and histopathology. On sagittal in situ magnetic resonance imaging, 1 case had a normal spinal cord, 2 had only focal lesions, 3 had a combination of focal and diffuse abnormalities, and 1 had only diffuse abnormalities. All spinal cords showed abnormalities on high‐resolution magnetic resonance imaging and histopathology, confirming the existence of diffuse cord changes as genuine multiple sclerosis‐related abnormalities while highlighting the limited resolution of in vivo magnetic resonance imaging.

The authors compare the spinal cord magnetization transfer ratio (MTR) of multiple sclerosis (MS) patients to healthy volunteers, relate MTR to spinal cord atrophy, and relate these and other magnetic resonance (MR) imaging parameters to disability. Sixty‐five patients with MS (14 relapsing remitting [RR] 34 secondary progressive [SP] and 17 primary progressive [PP] MS), and 9 healthy volunteers were studied using MR at 1.0 T. Disability of the patients was assessed using the expanded disability status scale (EDSS). Magnetic resonance parameters were upper spinal cord MTR, number of focal spinal lesions, presence of diffuse abnormalities, and spinal cord cross‐sectional area (CSA). Correlations were assessed using Spearman's rank correlation coefficient (r). Magnetization transfer ratio was higher in the controls (median, 33% range, 30%‐38%) than in patients with MS (median, 30%; range, 16‐36; p< 0.05). In patients with MS, EDSS correlated with spinal cord MTR, albeit weakly (r= ‐0.25, p< 0.05). Correlation between EDSS and spinal cord CSA was better (SRCC = ‐0.40, p< 0.01 ). No correlation was found between MTR and CSA (r= 0.1, p= 0.4). Combining MTR with spinal cord CSA improved correlation with EDSS (r= ‐0.46, p< 0.001 ), suggesting an independent correlation between disability and these 2 MR parameters. Expanded disability status scale scores were higher in patients who had diffuse spinal cord abnormality regardless of focal lesions (median, 6; range, 1.5–7.5) than in patients without diffuse abnormalities (median, 3.5; range, 0–8; p< 0.01). CSA was lower in patients with diffuse spinal cord abnormality (median, 62; range, 46–89 mm2) than in patients without diffuse abnormalities (median, 73; range, 47–89 mm2; p< 0.01). MTR was slightly lower in patients with diffuse spinal cord abnormalities (median, 29; range, 21%–33%) than in patients without diffuse abnormalities (median, 31; range, 16–36; t–test, p< 0.05).

Hypointense T1 lesions in multiple sclerosis patients correlate with axonal loss at autopsy and biopsy. We evaluated the chemical substrate of hypointense T1 lesions by using in vivo proton magnetic resonance spectroscopy, and analyzed the spectroscopic correlate of increased T1‐relaxation time measurements. Localized proton magnetic resonance spectroscopy and T1‐relaxation time measurements were performed in lesions, selected on T1‐weighted spin‐echo magnetic resonance images according to degree of hypointensity, in normal appearing white matter (NAWM) and in normal white matter of controls. In NAWM, prolongation of T1‐relaxation time and a decrease in N‐acetylaspartate (NAA) were present, compared with normal white matter. Severely hypointense lesions showed a lower concentration of NAA and creatine compared with NAWM and a lower concentration of NAA compared with isointense to mildly hypointense lesions. NAA concentration correlated with degree of hypointensity of lesions and with T1‐relaxation time within the spectroscopic voxel. Our results provide the first in vivo evidence of axonal damage in severely hypointense T1 lesions in multiple sclerosis patients. T1‐relaxation time correlates with the concentration of NAA in both multiple sclerosis lesions and NAWM, indicating that this parameter deserves further evaluation to monitor disease progression. Ann Neurol 1999;46:79–87

• In a series of 100 patients with head and neck carcinoma, the preoperative histopathologic findings of palpation and magnetic resonance imaging were compared with regard to both laterality and lymph node level (I through V). The overall error for palpation in detecting affected sides was 32%. Gadolinium-enhanced magnetic resonance images reliably upgraded 60% of the clinically negative necks, the overall error of magnetic resonance imaging being 16%. However, for both modalities, the sensitivity per level was too low to allow for selective neck dissections in case of only one positive level. These findings show that apart from primary tumor grading, magnetic resonance imaging can improve the preoperative grading of cervical lymph nodes. In selected cases, this may change the treatment plan to a "wait-and-see" policy or a more conservative type of neck dissection.(Arch Otolaryngol Head Neck Surg. 1991; 117:666-673)

Abstract.: Radioimmunotherapy (RIT) seems to be a realistic option for eradication of minimal residual squamous cell carcinoma of the head and neck (HNSCC), although uptake levels of radiolabelled monoclonal antibodies (MAbs) in tumour tissue vary strongly. The aim of this study was to obtain greater insight into the factors influencing the accumulation of MAbs in HNSCC. Twenty-seven HNSCC patients were injected with radiolabelled MAb E48 or U36 and underwent surgery 2 days after injection. Radioactivity was measured in tumour biopsies taken from the surgical specimen. Uptake levels were correlated with various patient, tumour and MAb characteristics, including age, sex, site, TNM stage, volume as assesssed by computed tomography or magnetic resonance imaging, degree of differentiation, antigen expression of the tumour, the particular MAb that had been injected and the MAb dose. A stepwise regression multivariate analysis showed that tumour volume is the most significant prognostic factor (P=0.01) for MAb uptake. In conclusion, a significantly higher MAb uptake is found in small tumours as compared to larger tumours. Therefore, RIT may be particularly effective in head and neck cancer patients when used in an adjuvant setting.

Thirty-five patients scheduled to undergo a neck dissection for squamous cell carcinoma of the head and neck were evaluated preoperatively by magnetic resonance (MR) imaging. Axial and occasionally sagittal and coronal images were obtained. To define the most reliable technique to detect cervical lymph node metastasis, we compared several MR pulse sequences with and without Gd-DTPA administration to histopathologic findings in the neck dissection specimens. T1-weighted spin echo combined with T2-weighted gradient recalled echo (GE) sequences were found to be more useful than any other combination of pulse sequences in localizing lymph nodes. On T2-weighted GE images, lymph nodes were depicted with intermediate to high signal intensity in contrast to low signal muscular and fatty tissue. Gadolinium DTPA enhanced T1-weighted GE images reliably depict central lymph node necrosis, the most specific criterion for lymph node metastasis.

A case of retrograde perineural tumor that spread from malignant melanoma of the face is reported. Contrast-enhanced CT and plain and contrast-enhanced MR studies, including fat suppression technique, showed tumor extension along the maxillary division of the trigeminal nerve. Histopathological examination of the surgical specimen revealed neurotropic malignant melanoma and confirmed the extent of tumor spread in the perineurium.