Calcaneonavicular Coalition - Fibrous/Cartilaginous

Axial IR

Axial T1

Sagittal IR

Sagittal T1

12 year old girl presented with foot pain.

MRI demonstrated enlongated broad anterior process of the calcaneum - anteater's nose - that showed abnormal articulation with the navicular bone.

Hyperintense signal noted at the abnormal articular ends on the IR images.

Diagnosis: Calcaneonavicular coalition Fibrous/Cartilaginous type.

Most common subtype of tarsal coalition.

Reference and further reading:

http://www.radsource.us/clinic/0812

Cowper's duct cysts

T1 sagittal

T2 axial

T2 coronal

T2 sagittal

30 year old presented with dysuria and occassional hematuria.

MRI of the pelvis demonstrated:

- a well defined hyperintense cystic lesion on T1 and T2
- Lesion lies in the midline in close approximation to the bulbous urethra and just below the prostate.


Diagnosis: Cowper's duct cyst.

Cowper's duct cyst:

• Cowpers glands - found in the urogenital diaphragm below the prostate

• Drains into the bulbar urethra

• Obstruction results in retention cysts

• Cowper's gland cysts are probably secondary to trauma or infection

• Large cysts can cause urinary obstruction, hematuria or infertility.

• Treated by marsupialisation or endoscopic incision.

References:

http://www.ajronline.org/doi/full/10.2214/AJR.06.0759
http://link.springer.com/article/10.1007%2Fs00247-001-0580-8

Perineal injury - Foreign body in the obturator externus - Ouch!!!

12 year old presented with a focal wound in the left aspect of the perineum.

According to the mother the boy came back from school with a perineal injury with no clear history or cause -said to be a fall. The boy initilally appeared hesitant to reveal the exact cause.

A few days later mother noticed fluid oozing from the wound with pieces of lead being extruded.

Boy was seen by a surgeon who referred him for an MRI.


Images demonstrates a linear hypointense signal structure (arrow) lying in the left obturator externus with surrounding muscle edema.

Further history according to the boy then revealed that at school an upright pencil was placed on the seat of the boy's chair by the adjacent student  as a prank just prior to the boy attempting to sit down - thus pierced through the left perineum - Ouch!!!

Osteopoikilosis - MRI features

Coronal IR

Coronal T1

Coronal T1

Rorschach

Young patient who presented with low back ache and came in for an MRI of the lumbar spine.

Lumbar spine images demonstrated a marked posterior disc extrusion at L4/5 accounting for the patient’s symptoms.

However on the routine coronal IR images multiple well defined ovoid hypointense foci were noticed in the pelvic girdle and femur.

An additional coronal T1 was acquired which demonstrates multiple numerous dark foci representing bone islands

Reminded me of the facial features of Rorshach from the cult graphic novel “The  Watchmen”

Diagnosis: Osteopoikilosis

Osteopoikilosis:  

- is a sclerosing bone dysplasia with multiple 

        enostoses

- develop during childhood and do not regress and 

        therefore are seen in all age groups

- asymptomatic 

- often found concurrently with osteopathia striata, 

        and melorheostosis 

- bone islands of osteopoikilosis are typically 

        clustered around joints and align themselves        

        parallel to surrounding trabeculae

- found in the appendicular skeleton and pelvis

- axial skelton is largely spared. It is rare for the 

        skull vault to be involved 

- is one of the skeletal “Don’t touch” lesions.

References:

http://radiopaedia.org/cases/osteopoikilosis-on-mri

http://radiopaedia.org/articles/osteopoikilosis-2

Large Degenerative Hemorrhagic Sessile Subserosal Uterine Fibroid

35 year old female patient presenting with abdominal distention and  pain.

Axial T2

Axial T1

Axial T2 fat saturation

Axial T1 Fat saturation

Coronal T2

Sagittal T2

Large lobulated heterogeneous mass filling the pelvis and extending into the abdomen lying in close approximation to the anterior aspect of the uterus. 

The mass demonstrates multiple large cystic components – high signal on T2 and low signal on T1.

Mass also demonstrates central large hyperintense component on T1 and T2 (*) that does not show drop in signal on T1 & T2 fat saturation sequences indicative of hemorrhagic component.

Multiple flow voids seen along the interface of the fibroid and the uterus.

Diagnosis: Large anterior sessile subserosal fibroid with cystic and hemorrhagic degeneration.

Extensor Carpi Ulnaris Tenosynovitis

Axial PDFS

Axial T1

Coronal PDFS

Sagittal T1

Patient presented with pain along the ulnar aspect of the wrist. No history of trauma.

Left extensor carpi ulnaris tendon appears swollen with diffuse hyperintense tendon sheath with fluid best seen on the PDFS images.

Hypointense thickening seen around the tendon on the T1 images.

Appearances are indicative of extensor carpi ulnaris tenosynovitis.

Liver Hepatocellular Carcinoma - HCC with classic tumor capsule

Focal well defined lesion in the right lobe of the liver.

T2 - is isointense to  the liver parenchyma with peripheral hyperintensity

  T1 - is hyperintense 

  Postcontrast - demonstrates intense arterial enhancement 
  with delayed tumor capsule.

  Classic features of HCC.

  The T1 hyperintensity is probably due to high copper  
  content and is seen in well differentiated HCC