T1 Gd-enhanced compared with CISS sequences in retinoblastoma: superiority of T1 sequences in evaluation of tumour extension.
BACKGROUND
As adequate therapy for retinoblastoma in young children depends on infiltration of extra-retinal structures, diagnostic modalities play an essential role.


METHODS
In this widely extended study, 80 children with retinoblastoma were studied with MRI (standard fat-suppressed Gd-enhanced T1, T2 thin-slice sequences (additionally with small loop surface coil), constructive interference in steady state (CISS) sequence covering the orbita). The images were analysed by two blinded neuroradiologists. Histology was used as the gold standard.


RESULTS
MRI assumed infiltration of extra-retinal structures in 13 of 80 patients of which ten were confirmed by histology. Affected extra-retinal structures were: optic nerve (five, of which two were on CISS and three on T1 with higher image resolution using the surface coil), scleral infiltration (five, of which four on CISS and T1) and ciliary body infiltration (one on CISS and T1). Another 61 enucleated patients did not have any extra-retinal infiltration in histology. The CISS sequence with multiplanar reconstruction was mainly helpful in revealing exact three-dimensional tumour extension with excellent clinical acceptance and pre-surgical planning but T1 fat-suppressed Gd-enhanced images were superior in revealing exact tumour extension.


CONCLUSIONS
CISS sequences allow to produce excellent anatomical images and to perform multiplanar reconstruction to better demonstrate tumour extension. However, T1-weighted sequences after contrast application are more sensitive (60 versus 40%) in detecting infiltration of the optic nerve but equal in detecting scleral infiltration.
Gizewski
Elke R
ER
Department of Diagnostic and Interventional Neuroradiology, University Hospital, Hufelandstrasse 55, 45127 Essen, Germany. elke.gizewski@uni-essen.de
Wanke
Isabel
I
Jurklies
Christine
C
Güngör
Ali-Riza
AR
Forsting
Michael
M
D002648:Child; D002675:Child, Preschool; D002924:Ciliary Body / Q000473:pathology; D003287:Contrast Media; D005134:Eye Neoplasms / Q000175:diagnosis; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009361:Neoplasm Invasiveness; D019574:Optic Nerve Neoplasms / Q000175:diagnosis; D009915:Orbit / Q000473:pathology; D019572:Retinal Neoplasms / Q000175:diagnosis*; D012175:Retinoblastoma / Q000175:diagnosis*; D015422:Scleral Diseases / Q000175:diagnosis; D012680:Sensitivity and Specificity; D016037:Single-Blind Method; D014604:Uveal Neoplasms / Q000175:diagnosis
D003287:Contrast Media; D019786:Gadolinium DTPA