Posts

Brain Degenerative Diseases and Gut Flora

-
Image
  Coronal CT of 86 years old showing moderate atrophy i hippocampi - MTA 2. Interesting articles indicate complex relation between our gut flora and neurodegenerative diseases. Especially in Alzheimer Dementia (AD). Gut Microbiota Regulation and Their Implication in the Development of Neurodegenerative Disease - Peilin Sun, Et al. Downregulation of Neurofilament Light Chain Expression in Human Neuronal-Glial Cell Co-Cultures by a Microbiome-Derived Lipopolysaccharide-Induced miRNA-30b-5p - Aileen I. Pogue, Et al. *(citations from above articles in cursive font) Studies indicate that anaerobic bacteria producing toxins cause brain inflammation that disrupts fragile neural connections in the elderly. My private theory is that hygiene of the mouth plays important role. Environmental factors of the modern civilisation, food preservatives and destruction of natural gut flora plays important role. Also fact that people live longer allows more time for neurodegenerative diseases to develop. O
Read more

Large Colloid Cyst in Cavum Vergae

-
Image
  Large Colloid Cyst in the roof of the Third Ventricle in Cavum Vergae - posteriorly in the Third Ventricle.  As usual there is no enhancement. CT with contrast shows higher attenuation due to cholesterol component of the fluid (mucin) in the cyst. Note higher than CSF signal on FLAIR and T2. There is no hydrocephalus and no oedema. You can compare it to other Large Colloid Cyst  expanding more anteriorly and the most typical in size and location  Colloid Cyst  - in the roof of the Third Ventricle near Foramina Monroi. Note small "dots" on the superior aspect of the Colloid Cyst representing Internal Cerebral Veins - that are not compromised. 
Read more

MRI Tractography - Brain Tumor

-
Image
Recently when reporting a brain MRI of a patient after tumor operation I came across beautiful functional and MRI Tractography images showing corticospinal tracts relation to the brain tumor in the frontal lobe. The interpretation of this study was that most ventral parts of the corticospinal tracts are located near tumor's dorsal part and the arcuate fasciculus was unaffected. Of course there were more images showing the arcuate fasciculus in more detail. The exam also included functional (fMRI) study showing motoric and speech locations. I'm not expert in this field but I wanted to show you that we are moving closer to using such functional studies in daily practice. 
Read more

Music Staff on MRI Lumbar Spine - fun

-
Image
As a new hobby project I recently took on some digital piano and synthesizer training. Part of it is to learn to read the notes. And somehow I keep on seeing five lines of staff even om MRI images :) ! This localizer incidentally even shows the grand staff . :)  You can see a little annular tear in a place of previous disk herniation.  The numbering of lumbar levels is often a matter of discussion. Previous exam has called the lowest lumbar vertebra as L5. I used the same numbering but in fact the vertebra that is called L5 on this image is a transitional vertebra that is partially sacral vertebra - so it could be called S1. I made a note on my report for the clinician that in case of operation it is important to correlate the level of operation with fluoroscopy .  For correct numbering of spinal lumbar levels I look for proximal parts of ribs 12 on sagittal images and count from what I assume as L5 upwards. When I have the whole spine or CT, especially with coronal images, then the
Read more

Large Colloid Cyst

-
Image
37 years old patient presenting with hydrocephalus caused by unusually large Colloid Cyst (CC) at the typical location in the region of foramina Monroe. CC have characteristic appearance as thin-walled cyst in this location filled with rather homogenous high density content (cholesterol and proteins) on non-contrast CT. This one is rather large. For "usual" size Colloid Cyst see this other case . CC can grow and obstruct foramina Monroe causing hydrocephalus - as in this case. Therefore neurosurgeons often recommend follow-up of CC that do not cause hydrocephalus or operate cases like this one.  Patient has been operated (new images on the left) with successful removal of the CC and reduction of the hydrocephalus. Operation using endoscope and only small trepanation frontally (not shown). Note how nicely the sulci are seen now after operation compared with pre-operative images. 
Read more

Ventriculus Terminalis - Fifth Ventricle

-
Image
sag T2, ax T2, ax T1 C+, ax T1 C+ FS sag T2, T1 C-, T1 C+, T1 C+ FS As additional finding at MRI of Lumbar spine an oval cystic lesion with thin well demarcated wall without contrast enhancement located in conus medullaris. This is a  ventriculus terminalis also known as fifth ventricle . It represents developmental remnant and is believed to have no clinical significance. It has typical location and lack of enhancement differentiates it from other cystic lesions in the spine as for example hemangioblastoma.  See also this interesting article: G. Liccardo - Fifth ventricle: an unusual cystic lesion of the conus medullaris  
Read more

CT Pelvimetry - Bäckenmätning

-
Image
Below is a short summary of the protocol for Pelvimetry (Bäckenmätning in Swedish). First a thick MIP is reconstructed on the scanner that covers whole pelvis. A line is drawn on the scanner that is later used for calibration on PACS workstation. Calibration of the previously measured line. On the above MIP the Transversal Inlet Diameter (Transverstingångsmått) is measured as the largest transversal distance in the pelvic inlet. As well as Intertubar Diameter (Intertubaravstånd) as distance between  ischial tubers . On sagittal reconstruction measure Sagittal Inlet Diameter (Sagittellt ingångsmått) as shortest distance between posterior part of symphysis pubis and promontorium (S1). As well as Sagittal Outlet Diameter (Sagittellt utgångsmått) as shortest distance between posterior part of symphysis pubis and fist mobile joint between sacrum and coccyx . On axial reconstruction (see topogram for level) measure Interspinal Diameter (Interspinal avstånd) a
Read more