Musculoskeletal #2 – Flashcard

13-year-old girl with knee pain for 2 months.

What do you see?

Click here to see the answer

Periphyseal (both knees) hyperintensity on sagittal fat suppressed T2 Weighted image (a) and Proton Density Weighted image (b) and hypointensity on sagittal T1Weighted image (c) (arrows).

FOPE: Focal periphyseal edema
– Mostly around the knees
– Both genders can be affected during skeletal maturation
– Painful manifestation of physiologic physeal fusion

Emergency #12 – Flashcard

31-year-old male:
* With flank pain
* Increased inflammatory parameters
* Decreased kidney function

Why is the right kidney less dense than the left?

Click here to see the answer

Obstructive kidney stone in the right proximal ureter (arrow) with secondary hydronephrosis

The increased pressure in the collecting system slows the ultrafiltration of urine and causes a slower enhancement of the right kidney in comparison with the left kidney, reflecting the impaired kidney function

Abdominal #1 – Long case

A 47-year-old female presented to the Emergency Room with bilateral upper extremity paresthesia, redness and edema. Her symptoms were not position-dependent. The patient was otherwise healthy, and did not take any medication. There is no pertinent surgical history.

An MR angiogram was ordered. The following images were obtained during bolus tracking:

Click here to see the images
Coronal MRV

MRA

T1-weighted images with fat saturation, following contrast administration


Click here to see the diagnosis

Diagnosis:

Superior vena cava (SVC) syndrome from right apical lung mass

Discussion:

In this patient with bilateral neurological deficits and edema, the suspicion of SVC syndrome must be addressed. This can be done using either an MRI or a CT protocol. In this case, the MRI scout bolus images (Image 1 & 2) revealed a pathognomonic sign for SVC occlusion:

Please note the marked collateral circulation following contrast administration to the right upper extremity with dilation of multiple intercostal and lateral thoracic veins. These collateral vessels then pool into the liver’s quadrate (segment 4 of the liver), giving the characteristic “hot spot sign”. This name originates from terminology in nuclear medicine, where it was occasionally seen in the case of SVC syndrome. Nowadays, it is more likely to be noticed on a CT or MR. This image also reveals the complete occlusion of the SVC.

Following fat-saturated T1-weighted axial image acquisition with contrast, the cause of the obstruction is evident. There is an infiltrative right apical mass which obstructs the SVC, as well as bilateral pleural effusions. Additionally, there is tumor thrombus noted in the left innominate vein, likely secondary to stasis.

Please review the following video and identify all these pertinent findings:

Emergency #11 – Long case

23-year-old male:
* HET
* Macroscopic hematuria and blood at urine meatus

What is the most likely diagnosis? What should we do next?

Click here to see the answer

 X-ray: Bilateral pelvis fractures discontinuity iliopectineal line most clearly left-sided

CT: Bilateral ramus superior/anterior iliac bone and ramus inferior pubic bone
Avulsion fracture symphysis pubis
Fracture sacrum on the right

Look also in soft-tissue setting!

Large hematoma posterior of symphysis pubis around urethra and perineum, lateral around the pelvic floor obturator internus muscles and cranially in the retroperitoneal Retzius space anterior of the bladder

Do a RUG: Retrograde Urethrogram. If intact, followed by CT Cystography

RUG shows contrast extravasation and complete rupture of anterior bulbous part of urethra, grade V isolated anterior injury. However, the rupture might be at the anatomic weak point, the bulbomembranous junction, meaning avulsion of the puboprostatic ligament and stretching of the membranous urethra. There is no contrast above the urogenital diaphragm (level of symphysis pubis). Contrast in the bladder is a residue from the IV contrast given for earlier total body CT.

Goldman classification urethral injury

Anterior urethra = Penile and bulbous part
Posterior urethra = Membranous and prostatic part

  • Type I: stretching the posterior urethra due to disruption of puboprostatic ligaments and hematoma, but urethra is intact
  • Type II: posterior urethral injury above urogenital diaphragm (between ischiopubic rami)
  • Type III: injury to membranous urethra, extending into the proximal bulbous urethra (i.e. with laceration of the urogenital diaphragm), thus contrast extravasation below diaphragm
  • Type IV: bladder base injury involving bladder neck and proximal urethrainternal sphincter is injured, hence the potential for incontinence
  • Type IVa: bladder base injury, not involving bladder neck (cannot be differentiated from type IV radiologically)
  • Type V: anterior urethral injury (isolated)

* In this case, no CT cystography was performed
* Patient was treated conservatively

Neuroradiology #11 – Long case

47-year-old male:
* Presented with epistaxis

Axial & coronal CT+C

Where is the lesion?

The bulk of the tumour is within the ethmoid sinuses extending inferiorly into the nasal cavity and superiorly into the intracranial cavity through the cribriform plates

What is the lesion like?

Enhancing soft-tissue tumor expanding the ethmoid sinuses and nasal cavity

T2, T1 and T1+C

What are the MRI signal characteristics?

Mixed signal intensity on T2, low signal on T1, and intense enhancement on post-contrast images

What is the differential diagnosis of paranasal sinus tumour?

* Olfactory neuroblastoma:  involves the ethmoid sinuses  and extends through the cribriform plate into the anterior cranial fossa. Usually, shows intense enhancement and may show calcifications. They are slow growing with sinus expansion

* Juvenile angiofibroma: benign locally aggressive vascular  tumor that affects adolescents. It is usually lobulated and expands the sphenopalatine foramen. Intense enhancement on post-contrast images

* Sinonasal carcinoma: heterogeneously enhancing mass that erodes the bone and may extend into the orbits or intracranially

* Lymphoma: low T2 signal with intense contrast enhancement and usually expands the bone

Diagnosis:Olfactory neuroblastoma