FRCR 1 ANATOMY QUESTION : 9

Sagittal T1 MRI Brain

Name the structure ? 

FRCR 1 ANATOMY QUESTION : 8

Sagittal T1 weighted MRI Brain

Name the labelled structure ?

Patterns of Enhancement in Cardiac MRI

Patterns of Enhancement in Cardiac MRI

• 1.       Delayed subendocardial enhancement :

a.       Myocardial Infarction ( in a coronary artery distribution).

b.       Eosinophilic Endocarditis

• 2.       Middle myocardial enhancement  : Cardiac Sarcoidosis.

• 3.       Diffuse myocardial enhancement with mural thickening : Cardiac Amyloidosis.

• 4.       Epicardial enhancement : Myocarditis

Happy Doctor's Day (India)

http://en.wikipedia.org/wiki/National_Doctors%27_Day

http://en.wikipedia.org/wiki/Bidhan_Chandra_Roy

FRCR 1 ANATOMY QUESTION : 7

Axial CT Petrous Bone : Bone Window

FRCR 1 ANATOMY QUESTION 7 : Name the labelled structure ? 

FRCR 1 ANATOMY QUESTION : 6

Sagittal T1 Weighted MRI Brain

Name the labelled structure ?

FRCR 1 ANATOMY QUESTION : 5

AXIAL CT Section - Skull Base

Question 5 : Name the labelled ?

FRCR 1 ANATOMY QUESTION : 4

Sagittal  T1 Weighted MRI

FRCR Anatomy Practice Question 4 : Name the structure labelled ?

FRCR 1 ANATOMY QUESTION : 3

Sagittal T1 Weighted MRI Brain

Question 3 : Name the labelled structure ?

FRCR 1 ANATOMY QUESTION : 2

AXIAL post contrast CT

 

Q2 : Name the labelled Structure ?

Solitary Pulmonary Nodule : Probability being Malignant

Solitary Pulmonary Nodule : Probability being Malignant : in decreasing order (Ss)

Spiculated margins
Size >3cm (defnitionwise this would be a 'mass' !!)
Seventy or more (>70yrs)
Speedy growth rate (Rapid doubling time)
Smoker
Superior location (Upper Lobes)

FRCR 1 ANATOMY QUESTION : 1

Q1 : - Name one anatomical structure located in the marked location. Can you also spot the main finding of this X-Ray?

AIR CRESCENT SIGN

Causes of AIR CRESCENT SIGN

    1. Aspergilloma -(Most Common).
    2. Angioinvasive.A.
    3. Echinococcal cyst.
    4. TB.
    5. Rasmussen aneusrysm
    6. Lung abscess
    7. Bronchogenic Ca.
    8. Hematoma.
    9. PCP.

Saprophytic aspergillosis (Aspergilloma) is commonly associated with thickening of the wall of the cavity and adjacent pleura (due to hypersensitivity reaction). The pleural thickening may be the earliest 'radiographic' sign before any visible changes in the cavity.

The 5 forms of PULMONARY ASPERGILLOSIS include:

1. SAPROPHYTIC

2. Allergic Broncho Pulmonary Aspergillosis (ABPA) / Hypersensitivity reaction.
- Long standing bronchial   asthma;
- Finger-in-Glove appearance,
- Segmental and Subsegmental bronchi of upper lobes
- fungal hyphal impaction of affected bronchi with distal mucoid impaction with 30% showing hyperdensity /   frank calcification in CT.

3. SEMI-INVASIVE / Nectrotizing Aspergillosis.
4. AIRWAY INVASIVE.
5. ANGIOINVASIVE ASPERGILLOSIS.

Ref : RG article, 2001.

Age related changes of Spinal Bone Marrow in T1 MRI

·   Human beings are born with red / hematopoietic marrow in their entire skeleton, which gets gradually replaced by fat as age progresses, and reaches the mature state by the age of 25years.

·          

    In adult pattern the red marrow is seen in the axial skeleton and proximal appendicular skeleton.

·          

    The red / hematopoietic marrow SI in neonates may be slightly lower than that of the skeletal muscle; thereafter marrow the signal intensity increases. So if the Marrow SI is found to be lower than of the normal skeletal muscle it almost always indicate a marrow pathology.

·           

    Under 40yrs of age, the axial skeleton contains fat only at the basivertebral vein region.

·          

    The replacement of the red to yellow marrow can occur in 3 patterns :

1.      Bandlike pattern along the endplate.

2.      Small foci of replacement.

3.      Larger globular areas of fatty replacement.

·              

    Near complete fatty replacement may be seen in some elderly patients and in cases of malnutrition or osteoporosis.

·           

    Conditions increasing the need for hematopoiesis like Chronic hypoxia, Anemia etc can cause reversal of fatty replcament, back to red marrow. These are usually seen as patches of T1 hypointensity.

·          

In cases of Sickle cell disease where the yellow marrow,can convert back to red marrow OR may never convert Yellow.
     
    The red marrow contains 40% of fat and yellow marrow contains 80% of fat !!!


      Ref  : AJR article MRI of spinal bone marrow -Part I. 2011.

The Chiari I Malformation

The main finding in Chiari Type I malformation is the Cerebellar Tonsillar Descent, resulting in the synonym of Congenital Tonsillar Ectopia. The measurements of the Clival length, Supraocciput, the tentorial slope and the Tonsillar Descent have been depicted in these following images.

MEASUREMENT OF CLIVAL LENGTH

MEASUREMENT OF THE SLOPE OF TENTORIUM

MEASUREMENT OF THE SUPRAOCCIPUT

Associated Syringomyelia in the lower cervical and upper thoracic spinal cord.

MEASUREMENT OF THE TONSILLAR DESCENT from the McRae's Line

Renal Duplex Systems

  

Case of Bilateral Renal Duplex System

Patient is a 36year old female, with h/o right ureterocele excision. 

USG was done initially, in which there was a tubular anechoic structure in right adnexa, mimicking a Hydrosalpinx. TVS confirmed the structure to be a dilated lower ureter, which was showing peristalsis and was seen in continuity with the right VUJ. This type of Ureteric Dilatation (Possibly secondary to reflux) can be easily mistaken for a hydrosalpinx. See the link below.

 CASE REPORTS: 'Duplex Megaureter Misdiagnosed as a Hydrosalpinx on Ultrasound '

Since there was right upper calyceal dilatation, Right Duplex System was suspected. LK was normal at time of USG.

LK shows two ureters	LK shows two ureters

CT images showed bilateral entirely duplicated ureters, bilateral upper moeity hydronephrosis. Right superior moeity ureter was seen inserted at a lower than normal position, with abnormal segmental dilatation of the distal 8-9cm.

Fetal PCA

FETAL POSTERIOR CEREBRAL ARTERY (PCA)

• In this anomaly, the Posterior Communicating artery(PCom) is prominent, with hypoplastic / Absent P1. Original Fetal PCA has absent P1, which is very rare.   

• Unilateral right OR Unilateral left PCA has an incidence of ~10% each. Bilateral Fetal PCA has an incidence of ~8%.

• The calibre of the PCom can be same as or greater than the PCA, and thereby the blood supply to the occipital lobes will be derived from the ICA through the PCom. The importance of this comes when ICA gets occluded, and will involve the ACA, MCA and PCA territories altogether (which will be difficult to explain by embolization). 

• Fetal origin of the posterior cerebral artery occurs when the embryonic posterior cerebral artery fails to regress.

Following are Axial Sections of NECT Brain of a middle aged female, which shows possible bilateral fetal PCAs. Here the Basilar artery bifurcation is not visualized and bilateral PComs are seen prominent (fig.3).

Small Basilar Artery anterior to Pons	Prominent bilateral PComs
Prominent bilateral PComs
P2 starts here!	Further continuation of PCAs(P2)