Pericardial Effusion Vs Pleural Effusion

Usually pericardial effusion(PE) is not found behind the left atrium,because the pericardial attachments are refleted onto the pulmonary veins.Somtimes,PE can be visualized in the oblique sinus,which is located behind the LA. A PE is anterior to the descending aorta,whereas a pleural effusion(PL) is posterior to the aorta.

What are Occipito-mental Views ? And lines for inspection.

(click on images to enlarge)

Occipito-mental View

The PA occipito-mental view provides excellent demonstration of the upper and middle thirds of the face including the orbital margins, frontal sinuses, zygomatic arches and maxillary antra.

Occipito-mental 30 View :

With 30 degrees of caudal angulation, the orbits are demonstrated less well. However, the zygomatic arches and the walls of the maxillary antra are seen clearly.

There are 3 lines for inspecting the OM views:

Line 1:

Look for widening of the zygomatico-frontal sutures
Fractures of the superior rim of the orbits
“Black-Eyebrow” sign due to orbital emphysema
Opacification / air-fluid level in the frontal sinuses

Line 2:

Look for fractures of the superior aspect of the zygomatic arch
Fractures of the inferior rim of the orbits
Soft tissue shadow in the superior maxillary antrum
Fractures of the nasoethmoid bones and medial orbits

Line 3:

Look for fractures of the inferior aspect of the zygomatic arch
Fractures of the lateral maxillary antrum
Opacification / air-fluid level in the maxillary sinuses
Fractures of the alveolar ridge
Compare the injured side with the uninjured side.

Long Case Discussion in Radiology

Noncontrast helical CT is the most sensitive and specific for the detection of renal stones

Which of the following tests is the most sensitive and specific for the detection of renal stones?

• A) KUB plain film
• B) Ultrasound
• C) Intravenous pyelography
• D) Noncontrast helical CT

The answer is D.

Compared with abdominal ultrasonography and KUB radiography, intravenous pyelography has greater sensitivity (64% to 87%) and specificity (92% to 94%) for the detection of renal calculi. Noncontrast helical CT is being used increasingly in the initial assessment of renal colic.
This imaging modality is fast and accurate, and it readily identifies all stone types in all locations. Its sensitivity (95% to 100%) and specificity (94% to 96%) suggest that it may definitively exclude stones in patients with abdominal pain.

Multiple transverse nonenhanced CT images demonstrate numerous 3-5-mm renal calculi (arrows) that were not depicted at US.

Chest -- CT scan describtion of Monod sign

Ultrasound image of a normal eye with lens

Since the eye is a fluid-filled structure, it provides a perfect acoustic window, producing images with excellent detail. The normal eye appears as a circular hypoechoic structure. The cornea is seen as a thin hypoechoic layer parallel to the eyelid.
The anterior chamber is filled with anechoic fluid and is bordered by the cornea, iris and anterior reflection of the lens capsule. The iris and ciliary body are seen as echogenic linear structures extending from the peripheral globe towards lens. The normal lens is anechoic. The normal vitreous chamber is filled with anechoic fluid. Vitreous is relatively echolucent in a young healthy eye.

Sonographically, the normal retina cannot be differentiated from the other choroidal layers. The evaluation of the retrobulbar area includes optic nerve, extraocular muscles and bony orbit. The optic nerve is visible posteriorly as a hypoechoic linear region radiating away from globe.

Normal ocular ultrasound

Recurrent Pyogenic Cholangitis (RPC)

Recurrent pyogenic cholangitis,Cholangiohepatitis, is an uncommon disease in the western world Most of these cases are seen in Asian countries.
The etiology is unknown, although some of these patients have biliary parasites.
The disease is characterized by a recurrent syndrome of bacterial cholangitis that occurs in association with intrahepatic pigment stones and intrahepatic biliary obstruction.
-These patients are also at risk of developing biliary cirrhosis and cholangiocarcinoma.
-The left lobe is the most common location of the disease due to the delayed drainage of the left system.

This C.T. image shows a typical case of Recurrent pyogenic cholangitis

There is focal dilatation of the bile ducts in the left lobe with stones.

Below there is another example of recurrent pyogenic cholangitis.There is intrahepatic lithiasis with focal diatation.
A case like this is indistinguishable from focal Caroli disease with secundary stone formation.