Head and Neck #13

What do you see?

Labyrinthitis Ossificans

Ossification of the membranous labyrinth, high-density bone deposition involving all the cochlear turns.

This usually occurs as a complication of suppurative labyrinthitis, either due to otomastoiditis or meningitis. Other causes include trauma, autoimmune diseases, and surgery.

Abdominal #16

What do you see on the following images?

Click here to see the answer

TB cervical lymphadenitis

Mild progression in size of multiple necrotic lymph nodes in bilateral supraclavicular, axillary regions, at all anterior and posterior cervical chain (more prominent at right side lower anterior cervical chain)

Musculoskeletal #30

38-year-old with left knee pain.
Showing multiple images:

Left knee X-ray:

STIR:

What is the most likely diagnosis?

Enchondroma

* Relatively common intramedullary cartilage neoplasms with benign imaging features
* Constitute ~5% (range 3–10%) of all bone tumors and ~17.5% (range 12–24%) of benign bone tumors

What are the radiological features?

Radiological features

* Narrow zone of transition
* Sharply defined margins
* Chondroid calcification, however, purely lytic in the hands/feet
* Sometimes expansile – more commonly in hands/feet
* Mild endosteal scalloping
* Do not “grow” through cortex (unless pathologic fracture)
* No bone destruction
* No periosteal reaction
* No soft tissue mass

What may be the complications?

Complications

* Pathological fracture
* Malignant transformation into chondrosarcoma

Differential diagnosis includes..

Differential diagnosis

* Bone infarct
* Chondrosarcoma
* Intraosseous ganglion

References

* Murphey MD, Flemming DJ, Boyea SR et-al. Enchondroma versus chondrosarcoma in the appendicular skeleton: differentiating features. Radiographics. 18 (5): 1213-37. Radiographics (abstract) – Pubmed citation
* Walden MJ, Murphey MD, Vidal JA. Incidental enchondromas of the knee. AJR Am J Roentgenol. 2008;190 (6): 1611-5. doi:10.2214/AJR.07.2796 – Pubmed citation
* Douis H, Saifuddin A. The imaging of cartilaginous bone tumours. I. Benign lesions. Skeletal Radiol. 2012;41 (10): 1195-212. doi:10.1007/s00256-012-1427-0 – Pubmed citation
* Mulligan ME. How to Diagnose Enchondroma, Bone Infarct, and Chondrosarcoma. (2019) Current problems in diagnostic radiology. 48 (3): 262-273. doi:10.1067/j.cpradiol.2018.04.002 – Pubmed

Musculoskeletal #29

30-year-old male:

· Persistent pain in his right ankle, for a year long, a synovial mass was demonstrated on ultrasound. · Ankle MRI was performed

What do you see?

Pigmented villonodular synovitis (diffuse articular form)

* Benign proliferative condition affecting the synovial membrane. Most commonly monoarticular
* MRI: Mass-like synovial proliferation with lobulated margins and articular erosions
– Signal -> T1: low-intermediate ; DPFS/STIR: heterogeneous with areas of high signal ; GE: blooming artifact ; T1GD: variable enhancement.

What is the differential diagnosis?

Differential diagnosis includes:
* Scarring – capsulitis
* Siderotic synovitis
* Synovial sarcoma

Abdominal #11

Clinical Information

– 53-year-old male
– Left adrenal nodule was incidentally found on a CT scan
– MRI was performed for better characterization

What are the Imaging Findings

– Left adrenal nodule with loss of signal intensity on out-of-phase image

What is the most likely diagnosis?

Adrenal adenoma:
– The most important characteristic feature is the presence of intracellular lipid.
– Chemical shift imaging is the most reliable technique for diagnosing adrenal adenoma: most of them demonstrate a loss of signal intensity on out-of-phase MR images.

Musculoskeletal #28

Prune Belly Syndrome

What are the features?

Features

There are three cardinal features:
– Bilateral undescended testicles
– Dilated urinary tract
– Deficient abdominal wall musculature.

These manifestations place patients with prune belly syndrome at risk for testicular malignancy, infertility, urinary tract infections, and renal failure.

The Prune Belly syndrome is also known as:
– Eagle-Barrett syndrome
– Abdominal musculation syndrome

What is the incidence of PBS?

– PBS has a contemporary incidence of 3.6–3.8 per 100,000 live male births
– It is a predominantly male diagnosis as <5% of those diagnosed are female

What are the major manifestations of PBS, giving rise to its alternative name of the triad syndrome?

– A deficiency of abdominal musculature leading to a wrinkled “prune- like” appearance of the abdominal wall.
– Bilateral intra-abdominal testes.
– Urinary tract dysmorphism. The urinary tract anomalies are characterized by differing degrees of renal dysplasia, hydronephrosis, dilated tortuous ureters, an enlarged bladder and a dilated prostatic urethra.

What percentage of patients with PBS are female? What are the major manifestations of PBS in a female?

– Only 5% of PBS diagnoses are female.
– Females exhibit only deficiency of abdominal wall musculature and the anomalous urinary tract without any gonadal abnormality.

Other abnormalities

– 75% of children with PBS have non-urinary tract abnormalities
– These abnormalities include respiratory (58%, e.g. pulmonary hypoplasia), cardiac (25%, e.g. patent ductus arteriosus, atrial septal defect, ventricular septal defect, tetralogy of Fallot), gastrointestinal (63%, e.g. constipation, incomplete rotation of the midgut) and musculoskeletal anomalies (65%, e.g. talipes equinovarus, scoliosis, hip dysplasia)

What is the incidence of prematurity

The incidence of prematurity in the PBS population is nearly 50%.

What is the perinatal mortality of those born with PBS?

– Perinatal mortality ranges between 10 and 29% in contemporary studies.
– Perinatal mortality is directly connected to the level of prematurity and severity of pulmonary hypoplasia.

What is the most common urinary tract abnormality?

Hydroureteronephrosis is almost always present and most commonly bilateral.
– The distal ureter is usually where massive dilation occurs; however the presentation is variable.
– Hydroureteronephrosis is almost never due to obstruction within the ureter, rather, lower urinary tract obstruction (posterior urethral valves), vesicoureteral reflux, and a histologic deficiency of smooth muscle and preponderance of fibrous tissue in the ureters leading to ineffective peristalsis