CASES

1. CASES BHUMIKA SUTHAR FIRST YEAR RESIDENT SSGH BARODA

2. Case - 1 • A young boy of 11 years presented with c/o wrist pain WITHOUT any significant soft tissue swelling.

6. Radiographic Findings: Wrist Films: • Lobulated lytic lesion of the distal radius abutting the articular surface and extending from the epiphysis into the proximal metaphysis. • matrix calcification are seen. MR: • The lesion demonstrates low signal on T1 weighted images and high signal on T2 weighted images with rings and arcs compatible with chondroid matrix.  • No extra-osseousoft tissue mass is seen.

7. Diagnosis • Chondroblastoma

8. PAEDIATRIC EPIHYSEAL LYTIC BONE LESIONS • CHONDROBLASTOMA • GCT • BRODIE’S ABSCESS • FIBROUS DYSPLASIA

9. CHONDROBLASTOMA • Age : 5-25 years • monostotic.  • COMMON SITES: long bones - femur, humerus, tibia. • Arise in an epiphysis • May extend into the metaphysis.  • A thin sclerotic rim may separate the tumor from the adjacent normal bone.  • Matrix mineralization (60%) typically punctate and less commonly in a pattern of rings and arcs. • Periostitis,Soft tissue masses, pathologic fractures are rare.

10. Tibia epiphyseal, rounded lytic lesion presenting well defined,regular margins, without surrounding sclerosis with central gross calcification.

11. Lucent area with well-defined margins in region of epiphysis-chondroblatoma in 11yrs old boy Coronal reconstructed ct confirmsmetaphyseal extension Coronal t1 weighted

12. PAEDIATRIC EPIHYSEAL BONE LESIONS • CHONDROBLASTOMA • GCT • BRODIE’S ABSCESS • FIBROUS DYSPLASIA

13. GCT

14. PLAIN RADIOGRAPH • Expansile ,Solitary lytic bone lesion • Closed epiphyses • No reactive sclerosis /No periosteal reaction • May break through cortex with cortical thinning • Soft-tissue invasion (25%) • Pathologic fracture (5%) • May cross joint space in long bones (exceedingly rare)

15. AP radiograph of the left wrist shows an expanded solitary lytic lesion involving closed epiphyses subarticular position of the distal ulna without rim of sclerosis or periosteal reaction which is typical for a giant cell tumor

16. Giant cell tumor of distal radius is eccentric and extend to the end of the bone

17. CT: • Tumor has soft-tissue attenuation (May contain foci of low attenuation (hemorrhage/necrosis) • Well-defined margins WITHOUT rim of sclerosis MRI • Heterogeneous signal intensity with low to intermediate intensity on T1WI & T2WI due to collagen and hemosiderin content.

18. Axial ct of proximal leg-Soft tissue attenuation with well defined margins and foci of low attenuation within due to h’age or necrosis. Coronal CT scan of a giant cell tumor of the distal ulna show soft tissue attenating lesion.

19. T2-weighted coronal MRIs of the wrist show a giant cell tumor located in a subarticular position in the distal radius. The lesion is heterogeneous and hyperintense.

20. NUCLEAR MEDICINE IMAGING • Diffusely increased uptake • May have "doughnut" sign of central photopenia (cold lesions with increased uptake around the rim) ANGIOGRAPHY: Hypervascular lesion

21. Bone scintigraphy shows hyperconcentration of tradiotracer in diastal radius due to GCT

22. PAEDIATRIC EPIHYSEAL BONE LESIONS • CHONDROBLASTOMA • GCT • BRODIE’S ABSCESS • FIBROUS DYSPLASIA

23. BRODIE’S ABSCESS

24. RADIOGRAPHIC APPEARANCE • Well demarcated Geographic lucency beneath epiphyseal plate. • A channel extending to the growth plate is almost diagnostic for infection. • No bone destruction/periosteal reaction • Early-soft tissue swelling • Late: irregular bone destruction • On occasion, the lesion appears to become tethered to the growth plate and cavity progressively elongates with growth extending from the epiphysis into the diaphysis in snakelike fashion (the serpentine sign)

25. AP and lateral radiographs of the distal tibia depicting an eccentrically located radiolucent lesion crossing the epiphyseal plate

27. SERPENTINE SIGN

28. Sagittal T1-weighted image of the left ankle depicts a well-defined lesion of decreased signal intensity in the anterior aspect of the distal tibial metaphysis, which extends into the adjacent growth plate and epiphysis.

30. PAEDIATRIC EPIHYSEAL BONE LESIONS • CHONDROBLASTOMA • GCT • BRODIE’S ABSCESS • FIBROUS DYSPLASIA

31. FIBROUS DYSPLASIA

32. X-rays: An abnormal area of bone that typically has an appearance similar to that of "ground glass." • There frequently is expansion of the involved area of bone. • May be deformity of the bone that is usually seen as bowing. CT scan: • see fractures and determine the weakness of the bone. MRI: • show the involved area of bone • may be helpful to determine whether or not areas have become cancerous. BONE SCAN: • A "hot spot" in the areas of involved bone.

36. PAEDIATRIC EPIHYSEAL BONE LESIONS GCT CHONDROBLASTOMA • CLOSED EPIHYSES • ABUT ARTICULAR SURFACE • NON SCLEROTIC MARGIN • SHARPLY DEFINED ZONE OF TRANSITION • ECCENTRIC • MRI: HETEROGENOUS <30YRS OPEN EPIPHYSES THIN SCLEROTIC RIM MATRIX MINERALISATION MRI: LOW TO HIGH BRODIE’S ABSCESS FD Geographic lucency Beneath epiphyseal plate C/F Soft tissue swelling Irregular bone destruction Ground glass appearance Bone expansion Bone deformity fractures

37. CASE 2 • A 17 YEARS OLD FEMALE PRESENTED WITH PAINLESS ANTERIOR MIDLINE NECK MASS. O/E: • Swelling moves on deglutition and on protrusion of tongue.

39. FINDINGS: sagittal ultrasound image (left is superior) shows a cystic anechoic structure just below the level of the hyoid bone. A small beak of the cyst can be seen passing superiorly over the hyoid.

41. Findings: • Soft tissue density lesion in midline below the level of hyoid bone embedded within the strap muscles.

42. Differential diagnosis for cystic anterior neck mass. • Thyroglossal duct cyst • Dermoid • Lipoma • Branchial cleft cyst • Lymphadenopathy • Abscess ( if complex mass )

43. Thyroglossal Duct Cyst • Most common congenital neck mass. • The second most common benign neck mass after benign lymphadenopathy. • An epithelial lined tubular structure which originates at the foramen cecum located at the base of the tongue. • The duct then descends through the musculature of the tongue through the mlyohyoid muscle . • By 7 weeks gestation, the thyroid gland has traversed the duct and is positioned anterior and lateral to the proximal trachea. • The duct usually involutes and disappears by 10 weeks.

45. Thyroglossal duct cysts develop anywhere along the course of the duct remnant, from the base of the tongue to the suprasternal region. • Frequently located in the region of the hyoid bone. • Cysts located above the level of the thyroid cartilage are usually midline, while cysts located below the level of the thyroid cartilage are off midline. • Presents as an asymptomatic, mobile mass in the anterior triangle of the neck WHICH MOVES ON DEGLUTITION AND ON PROTRUSION OF TONGUE. • Patients present in their teens or twenties because of enlargement and/or infection.

46. IMAGING FEATURES: • On ultrasound, they appear as hypoechoic masses with few septae and internal echoes. • CT scan :They are hypodense and well defined with minimal enhancement of the margins on contrast scans. • MR can also be used for superior soft tissue evaluation. • The lesions are hypointense on T1W images and hyperintense on T2W images. • These lesions usually lie medial to the sternocleidomastoid muscle, anterior to the carotid sheath and lateral to the thyroid gland.

47. Thyroglossal duct cysts location • Below the hyoid bone - 65% of cases • At the level of the hyoid bone - 20% of cases • Above the hyoid bone - 15% of cases

48. Thyroglossal duct cyst at & above the hyoid bone.

49. Infrahyoid & paramedian thyroglossal duct cysts

50. Thyroglossal duct cyst in a 3-year-old boy. Sagittal (a) and coronal (b) T2-weighted MR images show a hyperintense midline cystic mass of the foramen cecum .