Giant cell tumour of tendon sheath

T1 and STIR images in coronal plane; T2 GRE, T1 and T2 FS images in axial plane in a 25 year old female reveal a well-defined soft tissue mass along the ulnar aspect of flexor pollicis longus tendon abutting the proximal phalanx of left thumb. It shows hypointense signal on gradient echo image suggestive of paramagnetic substance.


GIANT CELL TUMOUR OF TENDON SHEATH:


This is the second commonest tumour of hand after simple ganglion cyst.


Types: It is of two types, the common localized type and the rare diffuse variety. The diffuse variety is considered the soft tissue counterpart of diffuse PVNS and is more common in lower extermities.


Age: 30-50 years, peak at 40-50 years.
Sex:Female to male ratio is 3:2


Presentation: Commonly occurs along the volar aspect of hand/ finger and is common adjacent to a DIP joint. It presents as a firm, lobulated, non-tender and slow growing mass which is fixed to underlying structures.


Imaging: 
X-ray may show cortical erosion, calcification etc.
USG shows a soft tissue mass along a tendon sheath with vascularity on color/ power doppler.
MRI shows low to intermediate signal on T1 and T2 spin echo sequences due to the presence of hemosiderin. This effect is further exaggerated and blooms on gradient echo sequences.


References:
-Wan JM, Magarelli N, Peli WC, Guglielni G, Sheli TW. Imaging of Giant cell tumour of the tendon sheath. Radiol Med.2010 Feb; 115(1): 141-51
-Verheyden JR. Giant cell tumour of the tendon sheath. emedicine.medscape.com

DURAL SINUS THROMBOSIS IN A PATIENT OF ULCERATIVE COLITIS

Axial FLAIR MR images and MR venograms showing acute infarcts in left cerebellar / left occipital regions due to thrombosis involving left transverse, left sigmoid sinuses along with left IJV.

Case history: 55 years old female with a long history of ulcerative colitis presenting with venous infarction due to dural sinus thrombosis.

Cerebral sinus thrombosis is an uncommon complication of ulcerative colitis( UC) in approximately 7.5%patients. It is probably due to genetic predisposition in combination with hypercoagulable state during relapse of UC.
It often presents with headaches and focal/ diffuse neurological signs.
It is important to be aware of this condition as it is a serious complication of inflammatory bowel disease with the potential of being fatal.

REFERENCE:
Nudelman RJ, Rosen DG, Rouah E, Verstovsek G. Cerebral Sinus Thrombosis: A Fatal Neurological Complication of Ulcerative Colitis.Pathology Research International: Volume 2010.

Lipoma arborescens

T1 and PDFS sagittal images of the left knee of a 27 year old male with history of recurrent joint swelling for the last two years showing frond like synovial thickening in the suprapatellar and posterior parts of the knee joint. The intensity of the frond like synovial thickening is suggestive of fatty tissue.There is significant synovial effusion.

-Lipoma arborescens is a rare condition affecting synovial lining of joints and bursae.
-Usually unilateral
-Most common joint affected-knee
-Rare in other joints like hip, shoulder, wrist. elbow
-There is frond like deposition of fat in the synovial lining.
-Clinical presentation is usually of painless recurrent joint effusion
-MRI is diagnostic as it shows the fatty nature of the fat deposition most commonly in the suprapatellar region of the knee joint.
-Treatment is synovectomy. It usually does not recur after surgery.
- Differentials are: synovial chondromatosis, PVNS, synovial hemangioma, inflammatory arthritis.