TEST YOURSELF

Q.All are true regarding hippocampal sclerosis except

a. The amygdala remains superior to temporal horn

b.  the CSF signal in the uncal recess of temporal horn / the alveus seprate amygdale from hippocampus

c. Both amygdala and hippocampus are hypointense to gray matter on almost all  MR pulse sequences.

d.The hippocampus may be slightly hyperintense to gray matter on FLAIR images

e. the posterior hippocampal boundary for volumetry extend to the crus of the fornix  

ANS-----??????

HAPPY TEACHERS DAY

HAPPY TEACHERS DAY

MY SALUTATION TO ALL TEACHERS

I have learned silence from the talkative, toleration from the intolerant, and kindness from the unkind; yet, strange, I am ungrateful to those teachers. 
Khalil Gibran

Thanks teacher for inspiring me to do well in life.
Whatever I have achieved in life is because of you.
Happy Teacher's Day!

FREQUENCY OF TNANSDUCER FOR SKIN USG

---Frequency of transducers used for examination of skin -----20 to 100 MHz ( depth of field 1 mm or less ,and in -plene resolution  is as high as < 50 micrometere).
---An adequate assesment of subcutaneous tissue can be made by means of transducers of 5 to 15 MHz.
--At 20 MHz ,the echogenic dermis can be separated from the hypoechoic subcutaneous fat .
---
----The thick subcutaneous fat of the lateral part of the proximal thigh can be examined by transducer of as low frequency as 5 MHz.
---Subcutaneous tissue appears as  USG as a discrete hypoechoic layer characterised by a hypoechoic background of fat and hyperechoic linear echoes correspomding to a web of connective tissue
----subcutaneous vein and nerve can be appreciated on USG.
----Normal Lymphatics in the subcutaneous tissue cannot be visualised with US.

GEYSER SIGN

----The geyser radiographic sign on shoulder arthrogram is characterized by leakage of dye from the glenohumeral joint into the subdeltoid bursa. The dye outlines the acromioclavicular joint. It is usually an indication of a full-thickness cuff tear of long duration

-----The geyser sign is an infrequently encountered imaging sign that was originally described on conventional fluoroscopy-guided shoulder arthrography.

----- The sign derives its name from its geyser-like appearance. On imaging, owing to a full-thickness SST tear, synovial fluid or intra-articular contrast extravasates from the glenohumeral joint into the subacromial bursa. The fluid, which then passes through the AC joint into an overlying cystic mass, is said to resemble a geyser spouting upwards.

-----Passage of fluid from the glenohumeral joint into the acromioclavicular joint on arthrography is referred to as the geyser sign. It can be seen with chronic rotator cuff tendon tear or after injury of the acromial undersurface during surgery.

FROM -----MANY SOURCES

CHASING HCC THROUGH MCQ

Q.All are true regarding hepatocellular carcinoma except

a.result of defferentiation through regenerative nodules to dysplastic nodules to HCC

b.regenerative nodules and dysplastic nodules are predominantly supplied by portal vein

c.HCC is solely supplied by abnormal ,unpaired hepatic arteries

d.HCC doesnot have portal blood supply  

e.HCC is commonly diagnosed on basis of histological confirmation

ANS---e

Hepatocellular carcinoma differs from most malignancies because it is commonly diagnosed on the basis of imaging features alone, without histologic confirmation

4.All are true regarding AASLD recommendation of  HCC except

a.US surveillace every 6 months in cirrhosis patients

b.new nodules > 1cm is suspicious of HCC

b.nodules stable for 2yrs should undergo routine surveillance

d.suspicious nodules require further investigation by Multiphasic CT/MRI

e.arterial phase washout

ANS.---e

Portal veinous or delayed washout is seen in HCC

Q.All are true regading AASLD criteria for diagnosis of HCC in cirrhosis

a.use of multiphasic CT/MRI

b.arterial hyperattenuation of lesion

c.portal venous phase hypoattenation of thelesion

d.delayed phase hyperatenuation of the lesion

e.portal veous phase /delayed phase washout

ANS.---d

---The radiologic diagnosis of hepatocellular carcinoma can be made at either CT or MR imaging, provided that a multiphasic contrast material–enhanced study is used.

----Characteristically, hepatocellular carcinoma enhances during the arterial phase because of its blood supply from abnormal hepatic arteries. Contrast medium in the surrounding liver parenchyma is diluted during this phase because the parenchymal blood supply arises mostly from the portal veins, which are not yet opacified. 

-----In the portal venous phase, the surrounding liver parenchyma becomes relatively hyperattenuated and the lesion is perceived to be hypoattenuated because of its lack of portal venous supply. This appearance is the so-called washout effect. Occasionally, washout is evident only during a delayed phase sequence.

------ Thus, a four-phase imaging study is required: non–contrast-enhanced phase, arterial phase, portal venous phase, and delayed phase

 ----- Images should be acquired in four phases: non–contrast-enhanced phase (before the injection of contrast material), late arterial phase (about 20 seconds after the injection), portal venous phase (50 seconds after the injection), and delayed phase (>120 seconds after the injection). 

-----The optimal timing for image acquisition in the delayed phase is debated, varying between 2 and 15 minutes after contrast material injection. 

------Contrast-enhanced US studies have shown that approximately 90% of hepatocellular carcinomas demonstrate washout by 5 minutes after injection of the microbubble contrast agent . Use of a 5-minute delay may be the practical choice for the timing of the delayed phase.

-----Precontrast and dynamic postcontrast T1-weighted three-dimensional fat-suppressed gradient-echo sequences are required, in addition to T2 (with and without fat saturation) and T1 in-phase and opposed-phase imaging. Timing of the dynamic contrast-enhanced sequences is the same as that used for the CT examination. Emphasis on precise breath-holding is extremely important.

-----Systematic review has shown that MR imaging is more sensitive than CT in the diagnosis of hepatocellular carcinoma (81% vs 68%) 

ECHOES OF HEPATOCELLULAR ADENOMA

Q.Hyperechogenicity of Hepatocellular adenoma is

 due to

a.fat only

b.glyogen only

c.air only

d.fat and glycogen

e.fat and air

1ANS.---d

HOW MUCH WE HAVE FORGOTTEN?--------FROM CLASS IX NCERT BOOK

Q.Who discovered canal rays ?

a.J.J. Thomson

b.E.Rutherford

c.E.Goldstein

d.Neils Bohr

ANS.----c

Q.What is canal rays?

a.positively charged radiations in a gas discharge

b. negatively charged radiations in a gas discharge

c. electrically neutral  radiations in a gas discharge

d.none of the above

ANS.----a

HCC-----summary from radiographics (2013),VOLUME 333,ISSUE 6

HCC

----Hepatocellular carcinoma is increasing in frequency. 

----It is a malignancy encountered mainly in the setting of cirrhosis; therefore, US surveillance and monitoring of AFP levels are recommended for patients with cirrhosis. 

---- The detection of focal liver lesions larger than 1 cm at routine US surveillance requires immediate further investigation with multiphasic CT or MR imaging. 

-----The characteristic imaging appearance of hepatocellular carcinoma is its enhancement pattern: arterial phase hyperenhancement and venous or delayed phase washout. 

-----The diagnosis of hepatocellular carcinoma can be made from a single imaging study when the characteristic enhancement pattern is demonstrated. 

----The BCLC system is the staging system of choice because it combines validated predictors of survival and links staging with treatment options. Stages are not determined on the basis of radiologic findings alone; imaging information is combined with clinical and biochemical parameters.

---- In the future, as classification systems evolve further, the diagnostic roles of diffusion-weighted imaging and hepatocyte-specific MR imaging contrast media and the therapeutic role of newer interventional techniques will become better defined.

Liver transplantation

1..What is the diameter of extrahepatic portal vein for successful  portal vein anastomosis in liver transplantation

a.>/= 2-3mm

b.>/= 4-5mm

c .>/= 6-7mm

d.>/= 8-9mm

e.>/= 10-11mm

1.---b

2..Which anastomosis is done first in liver transplant

a.IVC anastomosis

b.portal vein anastomosis

c.hepatic artery anastomosis

d.duct-duct anastomosis

e.none

2..---a

"Weeping willow trees” appearance ?

Q..All are true regarding imaging finding in cirrhosis of liver except

a.flying bat pattern on scintigraphy

b.bone marrow uptake of radionuclide

c.corkscrew appearance of intrahepatic areteries on angiography

d.weeping willow trees appearance on hepatic venography

e.Hypointense T2W appearance of regenerative nodules

ANS.----d

“Weeping willow trees” appearance (hepatic vein branches getting close ) on hepatic venography is noted in idiopathic portal hypertension

HIPPOCAMPAL SCLEROSIS

Q.All are true regarding hippocampal sclerosis except

a. The amygdala remains superior to temporal horn

b.  the CSF signal in the uncal recess of temporal horn / the alveus seprate amygdale from hippocampus

c. Both amygdala and hippocampus are hypointense to gray matter on almost all  MR pulse sequences.

d.The hippocampus may be slightly hyperintense to gray matter on FLAIR images

e. the posterior hippocampal boundary for volumetry extend to the crus of the fornix  

ANS.----c

Both amygdala and hippocampus are isointense to gray matter on all MR pulse sequences. The hippocampus, however, may be slightly hyperintense to gray matter on fluid attenuated inversion recovery (FLAIR) images due to incomplete suppression of CSF

MR SPECTROSCOPY

Q.All are true regarding MRS except

a. The acquisition of long echo time data  allows the detection of N-acetylaspartate (NAA), creatine (Cr/PCr) and choline (Cho) in normal brain

b. The methyl resonance of NAA produces a large sharp peak at 2.01 p.p.m

c.choline  produce resonance at 3.22 p.p.m

d. The acquisition of long echo time data  provides spectra with better signal to noise

e. The acquisition of short echo time data provides myo-inositol, glutamate and glutamine

ANS.---d

The acquisition of long echo time data (TE = 270 ms, TR = 3 ms) allows the detection of N-acetylaspartate (NAA), creatine (Cr/PCr) and choline (Cho) in normal brain, and lactate in areas of abnormality. The methyl resonance of NAA produces a large sharp peak at 2.01 p.p.m. and acts as a neuronal marker as it is almost exclusively found in neurons in the human brain, where it is found predominantly in the axons and nerve processes. The creatine peak (3.03 p.p.m.) arises from both phosphocreatine- and creatine-containing substances in the cell and choline (3.22 p.p.m) is thought to arise from choline-containing substances in the cell membrane.

The acquisition of short echo time data (TE = 30 ms, TR = 2s) has become the standard spectroscopy sequence and has the advantage of reduced effects from T2 losses and therefore provides spectra with better signal to noise. In addition, it detects additional resonances from metabolites with complex MR spectra such as myo-inositol, glutamate and glutamine .

The apparent diffusion coefficient (ADC) ----?T2 EFFECT

Q.All are true regarding the apparent diffusion coefficient (ADC) except

a. ADC requires sequences with at least two different b-values

b. ADC maps are solely based on differences of tissue diffusion

c. The ADC in the normal brain ranges from 2.94 × 10³mm

d. Areas with a decreased ADC appear dark on ADC maps

e. ADC maps are  dependent on  T2 effects

ANS.---e

ADC maps are solely based on differences of tissue diffusion,

 independent of any T2 effects. The ADC in the normal brain

 ranges from 2.94 × 10³mm² s¹ for CSF to 0.22 × 10³mm² s¹ for

 white matter; grey matter lies in between with a ADC of 0.76 × 

10³mm² s. Areas with a decreased ADC appear dark on ADC 

maps, which is the converse to diffusion-weighted images where 

areas of decreased diffusion appear bright.

ALEXANDER DISEASE

Q.All are true regarding Alexander disease except

a.enlarged  brain

b. substantial accumulation of Rosenthal fibers

c. The basal ganglia and cortex  usually relatively preserved

d. sparing of the subcortical U fibers

e. Cavitation  common

ANS.---d

There is no sparing of the subcortical U fibers  in Alexander disease. The cerebellum is less often affected than in other leukodystrophies. MR findings classically demonstrate increased signal intensity on the T2-weighted images in the frontal white matter .The occipital white matter and cerebellum are usually spared.

ureterocele

HEPATIC HEMANGIOMA

Q.All are true regarding MRI of hepatic hemangioma except

a.MRI ---the most sensitive modality for detection

b.T1 and T2 relaxation times considerably shorter  than that of solid hepatc tumour or normal heapatic parenchyma

c.hypointense on T1 image and significantly hyperintense on T2 image

d.light bulb sign on T2

e.show greater hypointensity on T1 and proton-weighted image compared to cyst

ANS.---b

T1 and T2 relaxation times of hemangioma are considerably longer  than that of solid hepatc tumour or normal heapatic parenchyma.So,hemangioma appear hypointense on T1 images and significantly hyperintense on T2images.Unlike most primary or metastatic liver lesions ,which generally have shorter T2relaxation times ,hemangioma typically retain their marked signal intensity on heavily T2-Weighted multiecho (echo delay times in excess of 100msec) accounting for the so called “light bulb” sign .The signal intensity of hemangioma resembles that of CSF ,which may be used as an internal reference standard on such images.Although simple hepatic cyst may demonstrate a similar hyperintensity on T2 images ,they can usually be distinguished by their relative greater hypointensity on both T1 and proton density

Hemangioma typically exhibit a homogenous hyperintense pattern ,whereas metastases commonly display a heterogenous amorphous appearance .Ringed morphology,indistinct margination ,or surrounding peritumoral edema. The light-bulb sign is not 100% specific for hemangioma ,as anywhere from 9% to 27% of hepatic metastases also demonstrate a homogeneous hyperintense pattern on T2 images.

CYSTOCELES---GREEN

 The traditional radiological classification of cystoceles, originally proposed by Green, is based on
----1. descent of the bladder neck,
---- 2.retrovesical angle—the angle between the proximal urethra and
---- 3.the trigonal surface of the bladder —and the degree of urethral rotation. 
-----Green type I is described as cystocele with open retrovesical angle (≥ 140°) and urethral rotation < 45°.
------ Green type II describes a cystocele with open retrovesical angle (≥ 140°) and urethral rotation between 45 and 120°, also called cystourethrocele. 
------A cystocele with intact retrovesical angle (< 140°) is defined as Green type III.

Both cystourethrography and ultrasound can distinguish between two main types of cystocele, i.e. cystourethrocele (Green type II) and cystocele with intact retrovesical angle (Green type III)
----. For this purpose, translabial ultrasound seems particularly useful since it is non-invasive and can easily identify not just the bladder, but also surrounding soft tissues, allowing assessment of bladder neck descent, retrovesical angle and degree of cystocele descent.

------. These two types of cystocele may have different etiologies and functional implications. Cystocele type III is more likely to be associated with levator trauma, i.e. avulsion injury, which is due to childbirth, associated with prolapse and prolapse recurrence
----. A Green type II cystocele is more commonly found in patients with stress incontinence and an intact levator
-----. Women with a Green type III cystocele tend to suffer more from voiding dysfunction than stress incontinence. The etiology of cystourethrocele is less likely to be caused by paravaginal defects than is the type III cystocele

Tc 99m

Q.All are true regarding Tc 99m sulphur colloid  except

a.minimal activity in blood after 20 minutes after IV bolus

b.60 to 70% taken by liver

c.particle size  approx. 0.3 to 0.5 microns in diameter

d. 3 to 8 millicuries injected for routine liver scan

e.indium 113m colloid used as alternative

ANS.---b

Tc 99m sulphur colloid is taken by the reticuloendothelial system –80 to 90 % by the liver ,5 to 10 % by the spleen,and a minimal amount by the bone marrow of normal individuals.

The indium 113m colloid is not an ideal radionuclide because of its high energy ,393 ke V. The In 113 generator needs replacement twice yearly as opposed to weekly with the Tc 99m generator.

PORTAL HYPERTENSION

q.A case of cirrhosis of liver undergoes Doppler study to detect the  portosystemic shunt .A rounded lucency is seen within the fissure for the ligamentum teres in transverse section .Doppler study shows tubular structure in saggital section running caudal from the left portal vein  along the ligamentum teres .What is the vein involved in the shunt formation

a.left gastric vein            

b.the paraumbilical vein

c.splenorenal shunt

d.esophageal varices

e.paraesophageal varices

ANS.---b