RadiologySpirit: 2010-11-14

Friday, November 19, 2010

ankle anatomy

1- First Metatarsal Bone
2-Navicular bone
3-Ankle joint
4-Lower end of tibia
5-Medial cuneiform
6-talus
7-Sustentaculum Tali
8-calcaneous
9-calcaneal tendon

http://anatomy.med.umich.edu/radiology/lower_limb/ankle_mri_zoom.html#

Thursday, November 18, 2010

facial shwanomma

section through the upper portion of the epitympanun. The labyrinthine portion of the facial nerve canal is expanded (black arrow) and an expansile lesion is present at the level of the geniculate ganglion (open arrow).

http://www.google.com.eg/imgres?imgurl=http://www.medcyclopaedia.com/upload/book%2520of%2520radiology/chapter10/nic_k10_.182.jpg&imgrefurl=http://www.medcyclopaedia.com/library/radiology/chapter10/10_2.aspx&usg=__7f6-NeEOM_vHfdYwj6vCG5pblvI=&h=342&w=300&sz=57&hl=ar&start=4&sig2=DrX7LzeqzcywrW0aYbTsCA&zoom=1&itbs=1&tbnid=_MTaaVXI74ud7M:&tbnh=120&tbnw=105&prev=/images%3Fq%3Dfascial%2Bschwanomma%26hl%3Dar%26sa%3DG%26gbv%3D2%26tbs%3Disch:1&ei=zp_lTPmNOpWH4QaFpPXwDg

mondini malformation

Non-contrast axial CT images through the temporal bones demonstrate incomplete partitioning of the left cochlea and nonvisualization of the modiolus resulting in confluency between the middle and apical segments. Compare this to the right cochlea, which is normal. There is also abnormal dilitation of the left vestibular aqueduct.

Mondini malformation occurs when there is abnormal development of the cochlea resulting in less than 2.5 turns and incomplete formation of the modiolus.

Mondini malformation refers to an anomaly of the cochlea in which the modiolus fails to develop properly in the seventh week of fetal life, resulting in a cochlea with only 1.5 turns instead of the normal 2.5 turns. In addition, the interscalar septum between the middle and apical segments fails to form leading to a confluent, sac-like cochlea.

There is an association with an enlarged vestibular aqueduct and anomalies of the vestibules and semicircular canals. In some cases, Mondini malformation may also be associated with Pendred Syndrome (bilateral sensorineural hearing loss and goiter)

http://www.google.com.eg/imgres?imgurl=https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjobFaatlj3qiNP9zcjW5P3kwR4A8vo1dW6HennIYLk_sNQPaCJDwXOx0kdF32EHnGmNFKjUBV1URdsIdDrdcn2f0p2dQFBT-j6jGIr2gY52_m-aadWputYN2ABEMXCMxol-pBrpGlsan8/s1600/2JZ0U1CR_MONDINI_CT_14_512X339_WM.JPG&imgrefurl=http://neuroradiologyonthenet.blogspot.com/2009/11/findings-non-contrast-axial-ct-images.html&usg=__KvnU61gXDQXri1zvGevPSpmYLqM=&h=339&w=512&sz=26&hl=ar&start=3&sig2=WtwPxPOOF8ZVA0TOEidJxA&zoom=1&itbs=1&tbnid=46vkbosvG4eWbM:&tbnh=87&tbnw=131&prev=/images%3Fq%3Dmondini%2Banomaly%26hl%3Dar%26sa%3DG%26gbv%3D2%26tbs%3Disch:1&ei=44_lTJKmMZDW4gawuKzwDg

michel anomaly

Axial CT scan shows right petrous bone aplasia with absence of inner ear structures. The medial wall of the middle ear is flattened (arrow), being in close contact with the infratentorial nervous structures. Note normal differentiation of the malleus.
Coronal CT scan shows a normally developed external and middle right ear. The long process of the incus (arrow) leans against the medial middle ear wall. The oval window, the stapes, and the second portion of the facial nerve are absent. A small dehiscence of the medial wall of the middle ear (arrowhead), located at the IAM, probably corresponds to the entrance of the facial nerve.

http://www.ajnr.org/cgi/content/full/20/2/281/F1

Vestibular aqueduct syndrome.

Vestibular aqueduct syndrome. Axial CT scan of the left ear shows abnormally large vestibular aqueduct (arrow). Patient has long-standing sensorineural hearing loss.

http://www.google.com.eg/imgres?imgurl=http://download.imaging.consult.com/ic/images/S1933033207707176/gr4-midi.jpg&imgrefurl=http://imaging.consult.com/image/topic/dx/Pediatrics%3Ftitle%3DVestibular%2520Aqueduct%2520Syndrome%2520(Pediatric)%26image%3Dfig4%26locator%3Dgr4%26pii%3DS1933-0332(07)70717-6&usg=__DKF9zVa-sv-ENxvwjuO34URxngc=&h=166&w=200&sz=4&hl=ar&start=2&sig2=Y6RJ1MmmQX_qgXflwn8lHQ&zoom=1&itbs=1&tbnid=35niSprqu1odYM:&tbnh=86&tbnw=104&prev=/images%3Fq%3Dvestibular%2Baqueduct%2Bsyndrome,ct%26hl%3Dar%26sa%3DG%26gbv%3D2%26tbs%3Disch:1&ei=H47lTM7YDcqH5Aa95PHwDg

glomus tympanicum

51-year-old woman with glomus tympanicum tumor. Axial (A) and coronal (B) thin-section CT scans of temporal bone (bone window) show 5-mm soft-tissue mass (arrow) filling hypotympanum of left middle ear cavity.

http://www.ajronline.org/cgi/content-nw/full/187/2/492/FIG16

cholesterol granuloma

A cholesterol granuloma (CG) is a special type of middle ear granulation tissue which is particularly prone to bleeding, and is a frequent cause of a haemotympanum

http://www.google.com.eg/imgres?imgurl=http://radiopaedia.org/uploads/radio/0001/6147/f9fdbef0cb4cf3606045f6c87d6383_gallery.jpg%3F1286930084&imgrefurl=http://radiopaedia.org/articles/cholesterol_granuloma&usg=__2mRldG-1RCzQr9MF7A5XsgEkac8=&h=411&w=441&sz=75&hl=ar&start=9&sig2=SifH1cSGp8VFU23uLLYrQQ&zoom=1&itbs=1&tbnid=x330tHUyp47gdM:&tbnh=118&tbnw=127&prev=/images%3Fq%3Dcholesterol%2Bgranuloma%26hl%3Dar%26sa%3DG%26gbv%3D2%26tbs%3Disch:1&ei=JIvlTKn4AoyK4gb8hNHwDg

Osteoarthritis at patellofemoral and medial compartments. No meniscal tear.

The axial proton density image with fat saturation shows loss of patellar articular cartilage focally at the median ridge and adjacent medial and lateral facets (long arrows). There is no articular cartilage loss at the lateral trochlea (short arrow). At the medial trochlear region (arrowhead), the intermediate signal represents pre-femoral fat pad, mimicking articular cartilage. The trochlear cartilage normally extends further proximally at the lateral aspect.

The sagittal proton density image with fat saturation, obtained near trochlear midline, illustrates the moderate (partial-thickness) articular cartilage loss, with subarticular bone marrow edema (arrow). At the most proximal patella, the articular cartilage remains normal (arrowhead). At the trochlear aspect, the prefemoral fat pad (arrowhead) contacts the patella. At the medial trochlea further distally, there was a small region of partial-thickness cartilage loss (not shown).

On coronal proton density image with fat saturation, mild (partial-thickness) articular cartilage loss is shown also in the medial compartment, femoral aspect (arrow). The vague region of signal loss at the lateral tibial plateau articular cartilage (arrowhead) is artifactual. The menisci are normal.

http://www.google.com.eg/imgres?imgurl=http://www.radsource.info/_images/1110_19.jpg&imgrefurl=http://www.radsource.info/clinic/1011&usg=__-ZkHtbFwP_GuWJe6iu_TqjpQYzg=&h=325&w=350&sz=48&hl=ar&start=10&sig2=hOkf-krjqbdzj3N7zvmKJQ&zoom=1&itbs=1&tbnid=zxR6fmbnPUPvzM:&tbnh=111&tbnw=120&prev=/images%3Fq%3Dpatellar%2Bcartilage%2Bdegeneration,mri%26hl%3Dar%26gbv%3D2%26tbs%3Disch:1&ei=agblTKqKHsaT4gargenvDg

please click on image to enlarge

http://www.google.com.eg/imgres?imgurl=http://www.scielo.br/img/revistas/rb/v39n3/en_a04fig01.gif&imgrefurl=http://www.scielo.br/scielo.php%3Fpid%3DS0100-39842006000300004%26script%3Dsci_arttext%26tlng%3Den&usg=__-KbAi_xtT9HcXB556JvPTJ0XuvI=&h=437&w=565&sz=180&hl=ar&start=14&sig2=CHPN7_GsE8QRCnXOWRKGPA&zoom=1&itbs=1&tbnid=hVVzMV3yPA6WmM:&tbnh=104&tbnw=134&prev=/images%3Fq%3DCHONDROMALACIA,KNEE,MRI%26hl%3Dar%26sa%3DG%26gbv%3D2%26tbs%3Disch:1&ei=KgPlTOSELMmWhQeE0qy_DA

An axial representation of a lateral patellar dislocation illustrates the dramatic transient lateral shift of the patella that occurs as the medial patella impacts upon the anterolateral aspect of the lateral femoral condyle.

An axial proton density-weighted image with fat suppression reveals complete disruption of the medial retinaculum at its patellar attachment (arrow) in another patient who recently suffered a lateral patellar dislocation.