JOURNAL CLUB

Dr Inayat Ullah

PG Résident Pediatrics

TITLE

Serial cranial ultrasonography

or early MRI for detecting

preterm brain injury?

Reference

Plasier A, Rates MMA, Ecury-Gosson GM,

et al. Arch Dis Child Fetal Neonatal Ed

2015; 100:F293-F300.

Institute of Study

Division of Neonatology, Department of Pediatrics, Erasmus Medical Center-Sophia, Rotterdam, The Netherlands.

Department of Radiology, Erasmus Medical Center, Rotterdam, The Netherlands

Department of Pediatrics, Koningin Paola Children’s Hospital, Antwerp, Belgium

Division of Pediatric Neurology,department of neurology, Erasmus Medical Center Rotterdam The Netherlands.

OUTLINE

o Background

o Objective

o Hypothesis

o Method

o Result

o Discussion

o Conclusion

o Already Known About Topic?

o This Study Adds?

BACKGROUND

Neurodevelopmental problems are

common in preterm infants. Early objective

diagnosis is important for prognostication

and decision making in NICU.MRI is suited

for quantitative assesment of injury and can

provide insight into pathogenesis of

preterm brain injury,

BACKGROUND Cont…

MRI is considered the best method to

consider and quantify diffuse non cystic

white matter injury WMI.

MRI is however, expensive time

consuming, and challenging for critically ill

infants.

BACKGROUND Cont

Cranial Ultrasonography CUS is relatively cheap directly

available, and allowes serial bedside scanning with

limited disturbances of infant.

CUS is used to detect germinal matrix hemorrhage and

intraventricular hemorrhage (GMH-IVH), and

periventicular leukomalacia PVL.

Ultrasound is however , observer dependent, and the

challenge of reproducible objective measurements and

problems to detect posterior fossa abnormalities and

cerebral cortical changes.

BACKGROUND Cont

Based on comparative studies between

MRI nd CUS regarding abilities to predict

outcome, MRI is proposed the imaging

method of choice for high risk preterm

infants.

However these studies donot use acoustic

window, high resolution USG and doppler

Imaging-as recommended by others.

OBJECTIVE

To investigate detection ability and

feasibility of serial cranial

ultrasonography and early MRI in

preterm brain injury.

Hypothesis

Dedicated advanced cranial

ultrasonography (CUS) is equally effective

as a single routine MRI scan at 30 weeks’

PMA to diagnose common brain lesions in

preterm infants and has higher clinical

availability.

Method

Study design: Prospectve cohort study

Method conti

Serial cranial USG and MRI were

performed according to standard clinical

protocol. In case of instability MRI was

postponed or cancelled. Brain images were

assessed by independent experts and

compared between modalities.

Method conti

Inclusion criteria:

Infants born below 29 weeks GA were

recruited prospectively.

Exclusion criteria:

Congenital malformation

Uncertainty regarding GA.

Refusal of parental informed consent.

Method conti

CUS and MRI were assessed for signs of

preterm brain injury by experienced investigators

independently using detailed classification

system that covers the types of brain injury.

IVH was graded according to Volpe.

WMI was classified to cystic PVL and diffuse

non-cystic WMI.

Cerebellar hemorrhages were calssified into folial

or lobar hemmorhages.

Results

Serial CUS was performed in all infants;

early MRI was often postponed (n=59)

cancelled (n=126).

Injury was found in 146 infants 47.6%.

Clinical characteristic differed significantly

between groups that were subdivided

according to timing of MRI.

Results

61 discrepant imaging findings were found.

MRI was superior in identifying cerebellar

hemorrhages, perforator stroke and

cerebellar sinovenous thrombosis CSVT.

Result cont

Study limitations

Exclusion of deceased patient, and those

referred to another hospital before MRI.

Inability to calculate sensitivity of MRI CUS

Inability to perform MRI in sick infants.

Discussion

The study demonstrates high number of

preterm infants with detectable brain injury

47.6%.

CUS has higher clinical faesibility than

MRI, which cannot always be performed in

severly ill infants.

This study demonstrates the complementry

role of both imaging modalities to detect

common preterm brain injuries.

Discussions.

MRI was better to detct GMH and posterior

fassa abnormalities, whereas CUS was

better at grade I-II IVH, perforator stroke.

Comprehensive application of CUS, usage

of supplemental acoustic windows,colur

doppler.high transducer frequency and

careful interpretation of images by

experienced sonologist result in high

accuracy in identifying certain lesion.

Discussions.

Serial CUS outperformed MRI scanning in

diagnosing focal lesion in 27 infants,

because of high sensetivity of detcting

perforator stroke,and CSVT.

Higher sensitivty of CUS in detecting grade

II IVH is due to its consective application

and timing of onset of IVH.

Conventional MRI do not always detect low

grade IVH.

CONCLUSION

Brain injury is frequently encountered in preterm infants 47.6%.

Advanced CUS is adequate in detecting preterm brain injury and deserves

more appreciation.

MRI is invaluable because it allowes quantitative assessments of

microstrucral brain properties and superior in detecting post-fossa

abnormalities.

However clinical use in preterm is limited due to logistics and safety

issues..

Dual use of sequential CUS and MRI provides high sensitivity to detect

common patterns of preterm brain injury .

Further research should focus on improvement of their complementary

applications.

WHAT'S KNOWN ON THIS SUBJECT

MRI is considered the optimal imaging

method to identify preterm brain injury,

but clinical circumstances may preclude

its use.

Cranial ultrasonography (CUS) allows

serial scanning at bedside and technical

developments are improving detection of

injury.

WHAT THIS STUDY ADDS

Combined use of advanced serial CUS

and MRI improves detection of common

patterns of preterm brain injury.

Compared to MRI, CUS seems more

sensitive for recognising acute

intraventricular hemorrhage , perforator

stroke and sinovenous thrombosis, but less

for small cerebellar hemorrhages.

WHAT THIS STUDY ADDS

(cont’d)

Clinical faesibilty of MRI is limited for

critically ill preterm infants.