Category Archives: Brain
The following article, titled “Biomarkers for the clinical evaluation of the cognitively impaired elderly: amyloid is not enough,” recently appeared in the journal Imaging in Medicine (June 2012). The authors argue that while incorporating biomarkers for assessing Alzheimer’s disease risk can help in patient prognosis, tests for amyloid, if used in isolation, have potential for harm, as amyloid tests are clinically useful only when evidence suggests progressive cognitive decline or neurodegeneration.
In a future editorial for the AJNR, the authors state that “the combination of MRI, CSF and genetic data, describing in the best possible way the … Continue reading >>
Cavernous angiomas belong to a group of intracranial vascular malformations that are developmental malformations of the vascular bed. These congenital abnormal vascular connections frequently enlarge over time. The lesions can occur on a familial basis. Patients may be asymptomatic, although they often present with headaches, seizures, or small parenchymal hemorrhages.
In most patients cavernous angiomas are solitary and asymptomatic. In recent times, increasing MR imaging has detected several such asymptomatic cases and has prompted a study into the genetics and natural history of this condition.
It is now known that cavernous angiomas have a genetic basis. Familial forms … Continue reading >>
A 39-year-old man with history of tingling sensation on the left half of Face.
MRI revealed a solitary lesion in the splenium of the corpus callosum, hyperintense on T2/FLAIR and hypointense on T1W images. There is diffusion restriction.
This lesion was presumed demyelinating in view of h/o upper respiratory tract infection. At 6-week follow up MRI the lesion resolved completely.
Various etiologies have been reported for transient splenial lesions like:
- Sudden withdrawal of antiepileptic drugs
- Brain infarction
- Multiple sclerosis
- Cerebral trauma
- AIDS dementia complex
- Infections like influenza, measles, herpes, Salmonella, mumps, adenovirus, varicella zoster, Legionnaires disease,
I read with great interest the editor’s choice in the Jan issue of AJNR ”Blood-Brain Barrier Permeability Assessed by Perfusion CT Predicts Symptomatic Hemorrhagic Transformation and Malignant Edema in Acute Ischemic Stroke” by Hom, Dankbaar, Soares, and colleagues. The article presented promising data for the combined use of clinical metrics and dynamic perfusion/permeability data to predict symptomatic HT and malignant edema.
However, I want to bring attention to the authors’ representative figure 1 (page 46). The follow-up hemorrhage 23 hours later appears on this single slice to be petechial in nature, and not a space occupying hematoma as stated by the authors, and certainly not … Continue reading >>
51-year-old male with no significant past medical history presented with 3+ months H/O intermittent dizziness, intermittent headaches, difficulty going down stairs and 3+ days H/O tingling and numbness on the right side of face, right hand and foot. MRI revealed increased T2 signal and swelling of the entire pons including the middle cerebellar peduncles with effacement/obliteration of the prepontine and CP angle cisterns. Center of the lesion was heterogeneously T2 hypointense and showed heterogeneous contrast enhancement, small focus of diffusion restriction, focal area of increased CBV and high choline to creatine ratio (2.18) & a tall lactate peak on MR … Continue reading >>
1. Marawar S, Girardi FP et al. National Trends in Anterior Cervical Fusion Procedures. Spine 2010;35:1454–1459. An 8-fold increase in prevalence and a similar increase in utilization of ACDF in the study population over a 15-year period (771, 932 discharges following ACDF were found). Not exciting reading, but a nice update on the tremendous utilization of cervical ACDF.
2. U-King-Im JM, Fox AJ et al. Characterization of Carotid Plaque Hemorrhage: A CT Angiography and MR Intraplaque Hemorrhage Study. Stroke 2010;41:1623-1629. The authors did not find mean plaque density to be a useful factor for prediction of MR … Continue reading >>
Open letter in response to NYT article from July 31, 2010 “The Radiation Boom After Stroke Scans, Patients Face Serious Health Risks” By WALT BOGDANICH
posted by Michael H. Lev and Max Wintermark
Every year in the United States, more than three quarters of a million people have a stroke, and approximately every 3 minutes someone dies from a stroke. A significant portion of stroke victims are young, and left with a devastating handicap for the rest of their lives. The monetary and societal costs of stroke represent a major economic challenge to the healthcare system. With stroke – as with heart attack – rapid treatment is essential to limit the extent of irreversible brain injury (“time-is-brain”), and rapid determination of the cause and degree … Continue reading >>
SIH (Spontaneous intracranial hypotension). Why should we ban “CSF hypovolemia” ? Because it’s a misnomer
Spontaneous intracranial hypotension (SIH) is now a fairly well known syndrome. Leakage of CSF is considered the pathogenetic factor, even in cases in which it is not demonstrated.
The loss of CSF volume explains the usual complaint of orthostatic headache, relieved by lying down, and the characteristic MRI findings: 1) thickening of the dura, enhancing after contrast medium administration, 2) subdural fluid collections, 3) sagging of the brain, 4) dilatation of the venous structures, which includes enlargement of the dural sinuses and veins, enlargement of the pituitary gland, and, in the spinal canal, engorgement of the epidural plexuses. All these … Continue reading >>
1. Samartzis D et al. Atlantoaxial Rotatory Fixation in the Setting of Associated Congenital Malformations. Spine 2010;35:E119–E127. New subtypes to the Fielding and Hawkins classification scheme for atlantoaxial rotatory fixation should exist to account for variations in anatomy and the existence of congenital anomalies/malformations.
2. Kim KH et al. Adjacent Segment Disease After Interbody Fusion and Pedicle Screw Fixations for Isolated L4–L5 Spondylolisthesis. Spine 2010;35:625–634. A low postoperative segmental lordotic angle, especially less than 20°, at index level was related with development of clinical ASD in both isthmic and degenerative spondylolisthesis patients.
An 11-year-old boy was involved in a car accident and presented in a semicomatous state.
Clinically he was diagnosed as having sustained a diffuse axonal injury and was treated conservatively.
A brain MRI was performed one month following injury and a repeat one 1 year later.
Susceptibility WI at the one month interval showed multiple microhemorrhages in both frontal lobes.
The one year follow-up MRI showed diffuse, symmetric, confluent hyperintensities in the periventricular WM and these findings were not present on the initial MRI.
The question is whether the WM changes seen at the one-year follow up study are related to the diffuse axonal injury. … Continue reading >>