Orbital Interstitial Fluid: Evidence of a Potential Pathway for Extracranial Cerebrospinal Fluid Absorption.

BACKGROUND AND PURPOSE: The aim of the study was to describe the prevalence and characteristics of orbital interstitial fluid seen on magnetic resonance (MR) images of infants and young children. MATERIALS AND METHODS: Fat-suppressed axial T2-weighted MR images of 100 consecutive infants and young children (<6 years) without orbital pathology were retrospectively reviewed by 2 neuroradiologists. The presence, location, and extent of high-signal orbital interstitial fluid were characterized and tabulated as a function of age. RESULTS: Orbital interstitial fluid was detected in 90 (90%) of the 100 subjects overall, present in 100% (75/75) of infants and children younger than 3 years, 75% (12/16) of those aged 3 to 5 years, and 33% (3/9) of those aged 5 to 6 years. The fluid was bilateral and symmetric in all cases. Two morphologic patterns were distinguished, which often co-existed: (1) a focal discrete curvilinear band of fluid in the posterior-lateral orbit, more common in younger patients, and (2) an ill-defined, lace-like pattern primarily in the superior orbit seen in subjects of all ages. CONCLUSIONS: Orbital interstitial fluid as detected by fat-suppressed T2-weighted MR imaging is a nearly universal finding in infants and young children and should not be considered pathologic. It may have either a focal or lace-like pattern or both. Orbital interstitial fluid decreases in size and prevalence as a function of age but is still present in nearly half of children aged 4 to 6 years. Possible explanations concerning the nature and origin of this fluid are presented, including the fascinating possibility that the fluid represents an extracranial pathway for outflow of cerebrospinal fluid.

Risk of brain tumors from wireless phone use: retraction.

"Risk of Brain Tumors From Wireless Phone Use," by Rash Bihari Dubey, Madasu Hanmandlu, and Suresh Kumar Gupta, has been retracted by the editor of JCAT after finding issues related to plagiarism.

Skull fractures through parietal foramina: report of two cases.

Enlarged parietal foramina are related to a condition in which defective intramembranous ossification of the parietal bones results in enlargement of the normal foramina. Although generally believed to be a benign variant, scalp defects, seizures, and structural brain abnormalities have been reported in a small percentage of affected patients. These 2 cases now present evidence that parietal foramina constitute structural weak spots in the calvarium that may potentially increase risk of skull fracture after trauma.

Internationalization of the American Journal of Roentgenology: 1980-2002.

OBJECTIVE: The objective of this study was to analyze trends in the number of articles from international authors submitted to or published by the American Journal of Roentgenology (AJR) between 1980 and 2002. MATERIALS AND METHODS: More than 5000 articles published by the AJR during three 3-year periods (1980-1982, 1990-1992, and 2000-2002) were categorized by country of residence of the corresponding author, type of article, subject matter and age of patients, organ system, and radiologic technique. Additionally, 6202 manuscripts submitted to the AJR (1991-1992 and 2001-2002) were used to calculate the acceptance rates for the two 2-year periods. RESULTS: The percentage of articles published by the AJR from international authors was 10% (158/1610) in 1980-1982, 25% (441/1788) in 1990-1992, and 37% (602/1624) in 2000-2002 (p < 0.0001). Japanese, South Korean, and German authors achieved the largest increases during the 22 years covered by our research, and Canada had the largest decrease. The increase in international articles at the AJR was accompanied by an absolute decrease in publications from authors in the United States. Nonetheless, during 2000-2002, the acceptance rate for major papers from authors in the United States was 45% and the acceptance rate for foreign authors was 31%. During 1990-1992, the acceptance rates for major papers were 33% and 27%, respectively. CONCLUSION: The contents of the AJR reflect a continually increasing number of international articles during the past two decades.

Pseudo-subarachnoid hemorrhage: a potential imaging pitfall associated with diffuse cerebral edema.

We report CT findings in seven patients with diffuse cerebral edema and increased attenuation in the basilar cisterns resembling subarachnoid hemorrhage. On the basis of autopsy (three cases) and lumbar puncture (four cases) findings, true subarachnoid hemorrhage was reasonably excluded. Pathophysiologic changes that occur with diffuse cerebral edema are explored, with proposed explanations for the appearance of a pseudo-subarachnoid hemorrhage.

Diffusion-weighted imaging of cerebral infarctions: are higher B values better?

PURPOSE: The purpose of this work is to determine whether high -value ( = 3,000 s/mm ) diffusion-weighted (DW) imaging is superior to low -value ( = 1,000 s/mm ) DW imaging for the detection of cerebral infarctions older than 6 h. METHOD: Echo planar DW imaging was performed at 1.5 T in 26 consecutive patients (mean age 66 years) referred for clinical diagnosis of definite acute/subacute cerebral infarction (6 h to 14 days old). The DW imaging sequences were performed using matched parameters (TR = 10,000 ms, TE (eff)= 97 ms, FOV = 24 cm, 128 x 192 matrix, slice = 5 mm, NEX = 2) with values of 1,000 and 3,000 s/mm. Areas of infarction were compared visually by two experienced neuroradiologists. Quantitative measures of MR signal and noise levels in the infarcted areas compared with contralateral normal brain were also obtained. RESULTS: The median time after infarction was 2.5 days (range 10 h to 14 days). By visual inspection, all infarctions were reliably identified on both the = 1,000 and the = 3,000 images. The gross signal ratio (infarct/normal brain) was approximately 33% higher in the = 3,000 images, but the = 3,000 images were rated as noticeably "noisier" by both observers in every case. This visual observation was confirmed quantitatively: The signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were 70% and 51% higher in the = 1,000 than the = 3,000 images (p < 0.0005 for both). CONCLUSION: For the evaluation of late acute/subacute cerebral infarctions, high -value ( = 3,000 s/mm(2) ) DW imaging offers no apparent diagnostic advantages compared with = 1,000 images and is significantly inferior in terms of SNR and CNR.