RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES, KARNATAKA, BANGALORE.

PROFORMA FOR REGISTRATION OF SUBJECTS FOR DISSERTATION
TO BE SUBMITTED IN DUPLICATE
1. / NAME OF THE CANDIDATE AND ADDRESS
ADDRESS FOR CORRESPONDANCE / DR .RANOJI MANE
H.NO 8-1545/27, SHIVAJI NAGAR, HUMNABAD ROAD, GULBARGA. 585104
DR.RANOJI MANE
POST-GRADUATE IN RADIODIAGNOSIS,
DEPTARTMENT OF RADIODIAGNOSIS,
M.S. RAMAIAH MEDICAL COLLEGE.
BANGALORE. 560054.
2. / NAME OF THE INSTITUTION / M.S.RAMAIAH MEDICAL COLLEGE, BANGALORE. 560054.
3. / COURSE OF THE STUDY AND SUBJECT / M.D RADIODIAGNOSIS
4. / DATE OF ADMISSION TO THE COURSE / 31-05-2011
5 / TITLE OF TOPIC / Role of Susceptibility-weighted imaging (SWI) in evaluation of acute ischemic stroke patients.

6. Brief resume of intended work.

6.1 Introduction and need for study:

Stroke is a second leading cause of death globally and is a major cause of long term disability. Cerebrovascular

ischemia from thromboembolism or atherosclerotic stenosis leads to acute infarct with or without hemorrhage. MRI

provides critical information in the setting of acute stroke that can be used to confirm a diagnosis and direct both

acute therapeutic interventions and long-term treatment decisions. MRI can identify regions of active ischemia,

hemorrhage, and vessel occlusion. With appropriate processing, MRI has the potential to identify regions of core

infarct (ischemic core) and salvageable tissue (penumbra).

However, MRI must reliably detect acute hemorrhage in order to be the only imaging study used before

thrombolysis.

Conventional MRI is insensitive to detect micro bleeds and petechial hemorrhages in ischemic infarction.

MRI can identify hyper acute hemorrhage using susceptibility weighted imaging (SWI). SWI is a T2-weighted

gradient echo post-processing reconstruction technique that accentuates the paramagnetic properties of blood

products and is very sensitive for the detection of intravascular venous deoxygenated blood as well as extra vascular

blood products.

The ability to detect early blood products in patients with acute stroke has made SWI a powerful technique in the

evaluation of stroke patients. SWI may be used to localize the affected vascular territory.

Hypothesis: Susceptibility-weighted imaging (SWI) is superior to conventional MR imaging sequences for

the detection of hemorrhagic foci in brain of patients with acute ischemic stroke.

6.2 Review of literature

Studies have shown the ability of SWI in detecting intracerebral hemorrhage (ICH) in hyper acute and acute stroke,

further helping to distinguish ischemic from hemorrhagic stroke. (1, 2,) A study conducted by Linfante et al showed

that hemorrhagic foci in an acute infarct is detected as early as 23 minutes from the symptom onset.(2) SWI is

sensitive in detecting hemorrhage and thus allows better visualization of the hemorrhagic region. (3)


Study have shown that SWI is more sensitive in detecting hemorrhage inside acute infarct lesions than CT and 2D

gradient recalled-echo (2D-GRE) T2*-weighted imaging. (4) SWI is sensitive in detecting hemorrhages occurring in

the brain parenchyma, intraventricular hemorrhage and subarachnoid hemorrhage .(5)

SWI can provide additional information in detecting acute thromboemboli that occlude arteries (dark MCA sign),

predicting the probability of potential hemorrhagic transformation before thrombolytic treatment by counting the

number of microbleeds and early detection of hemorrhagic complication after intra-arterial thrombolysis and in

cerebral venous thrombosis.

6.3 Objectives of study;

1) To identify hemorrhagic foci in patients with acute ischaemic stroke by SWI

2) To compare the detection of hemorrhagic foci in patients with acute ischaemic stroke by SWI versus conventional MR imaging.

3) To identify the intra-arterial clot as depicted by the dark MCA sign.

7. Materials and methods

7.1 Source of data: - Cases of acute ischemic stroke patients who have undergone MR imaging in department

of Radio diagnosis, M.S.Ramaiah hospitals, Bangalore will be included in this study.

The study period is for eighteen months October 2011 to March 2013.

Study design: - Hospital based cross sectional study.

Study area: - M.S.Ramaiah Medical College and hospitals, Bangalore.

Sample size:- Sample size was estimated by using N – master software, from the cited literature (6) assuming

the proportion of stroke detected by SWI as 66.67% with relative precision of 15% and desired confidence interval

of 95% , the minimal sample size required is estimated to be 88 cases for satisfactory statistical analysis.

Statistical analysis;- Mean, standard deviation and proportion(%) for describing the data, Chi – square test of

proportion shall be employed to assess the statistical significance of difference between the SWI and conventional

MR sequences in detecting hemorrhagic foci in an acute infarct. ANOVA shall be used to compare the differences in

mean values of detection of hemorrhagic foci in an acute infarct between SWI and conventional MR sequences.

Level of significance shall be fixed at 0.05.

7.2 Method of data collection: - All patients presenting with acute symptoms of stroke, referred from

emergency, out patient or inpatient department will be studied on 1.5 Tesla MRI scanner (Magnetom Avanto;

Siemens Erlangen ,Germany). The following sequences will be performed, sagittal T1 weighted images, axial T2

weighted images, Fluid attenuated inversion recovery (FLAIR), Diffusion weighted imaging (DWI) including

Apparent diffusion coefficient (ADC) and Susceptibility weighted images(SWI).

Imaging protocol for SWI will be TR – 48 ms, TE - 40ms, flip angle (FA) - 15degrees, slice thickness –

2.5 mm, inter slice gap 0.5mm, bandwidth - 80 kHz and field of view (FOV) – 230 x 200 mm, matrix 256

x 192 mm, acquisition time 3 minutes 29 seconds. Four sets of images will be generated including phase, magnitude,

SWI and minimum intensity projections which will be analyzed.

The following data will be recorded – patient’s age, sex, clinical history, territory and type of infarct, extent of

infarct, presence or absence of hemorrhage in SWI along with extent of hemorrhage, presence or absence of dark

MCA sign, presence of prominent cortical and/or intramedullary veins in the vicinity of infarct and presence or

absence of micro bleeds.

Inclusion criteria;-

1) All ages and both sexes.

2) Patients with acute symptoms of stroke in whom MR imaging is done with in 7 days showing restriction on

Diffusion weighted imaging (DWI).

Exclusion criteria;-.

1)  Causes of hemorrhage other than acute ischemic stroke like cerebral amyloid angiopathy.

2)  Follow up MR imaging of asymptomatic known cases of patients with stroke or chronic stroke patients.

3)  Patients in whom MR imaging is clinically indicated, but cannot be performed due to conditions like

cardiac pacemaker, cochlear implants, and other routine contraindications for MRI.

7.3 Does the study require any investigations or interventions to be conducted on patients or

other humans or animals?

Yes. MRI study of brain in suspected stroke patients.

7.4 Has ethical clearance been obtained from your institution?

8. List of references.

1. Patel MR, Edelman RR, Warach S. Detection of hyperacute primary intraparenchymal hemorrhage by magnetic

resonance imaging. Stroke.1996; 27:2321-2334.

2. Linfante I, Llinas RH, Caplan LR, Warach S. MRI features of intracerebral hemorrhage within 2 hours from

symptom onset. Stroke. 1999; 30: 2263-2267.

3. Sehgal V, Delproposto Z, Haacke EM, et al. Clinical applications of neuroimaging with susceptibility-weighted

imaging. J Magn Reson Imaging 2005;22:439–50.

4. Wycliffe ND, Choe J, Holshouser B, et al. Reliability in detection of hemorrhage in acute stroke by a new three-

dimensional gradient recalled echo susceptibility- weighted imaging technique compared to computed

tomography:A retrospective study. J Magn Reson Imaging 2004;20:372–77.

5. S. Mittal,Z. Wu,J. Neelavalli, E.M. Haacke . Susceptibility-Weighted Imaging: Technical

Aspects and Clinical Applications, Part 2. AJNR Am J Neuroradiol. 2009; 30:232-252.

6. Hui-fai Chan .Prediction of spontaneous haemorrhagic transformation of acute major cerebral infarcts by

magnetic resonance imaging with Susceptibility weighted imaging (SWI) sequence.

Hong Kong Med J Vol 15. No 6,2009,33.

9 / SIGNATURE OF THE CANDIDATE
10 / REMARKS OF THE GUIDE / BY EARLY DETECTION OF HAEMORRHAGIC FOCI IN ACUTE ISCHEMIC STROKE BY SWI WILL HELP THE CLINICIAN TO START APPROPRIATE TREATMENT, THERE BY PREVENTING THE FURTHER DAMAGE TO BRAIN PARENCHYMAL CELLS.
11 / NAME AND DESIGNATION OF
GUIDE / Dr. UMESH KRISHNAMURTHY , M.D.R.D
PROFESSOR.
DEPARTMENT OF RADIODIAGNOSIS,
M.S.RAMAIAH MEDICAL COLLEGE.
BANGALORE. 560054.
11.1
11.2 / SIGNATURE
11.3 /
CO GUIDE
/ Dr. ANAND K, M.D.R.D
ASSOCIATE PROFESSOR,
DEPARTMENT OF RADIODIAGNOSIS,
M.S.RAMAIAH MEDICAL COLLEGE.
BANGALORE. 560054
11.4 / SIGNATURE
11.5 / HEAD OF THE DEPARTMENT / Dr. ASHOK A.KUMAR, M.D.R.D
PROFESSOR AND HEAD OF DEPTARTMENT,
DEPARTMENT OF RADIODIAGNOSIS,
M.S.RAMAIAHMEDICAL COLLEGE.
BANGALORE. 560054.
11.6 / SIGNATURE
12
12.1 / REMARKS OF DEAN AND PRINCIPAL
Dr. G SARASWATI RAO. M.D.
PRINCIPAL AND DEAN.
M.S. RAMAIAH MEDICAL COLLEGE.
BANGALORE. 560054.
12.2 / SIGNATURE