PMID- 20524826
OWN - NLM
STAT- MEDLINE
DCOM- 20110310
LR  - 20110202
IS  - 1933-0693 (Electronic)
IS  - 0022-3085 (Linking)
VI  - 114
IP  - 2
DP  - 2011 Feb
TI  - Magnetic resonance imaging dynamics of contrast medium uptake in vestibular 
      schwannomas.
PG  - 394-9
LID - 10.3171/2010.5.JNS10307 [doi]
AB  - OBJECT: Efficacy of radiosurgery in vestibular schwannoma (VS) is usually 
      documented by changes of tumor size and by loss of contrast enhancement in MR 
      imaging within the central portion of the lesion. Until now, however, correlation 
      between contrast enhancement and timing of image acquisition in nontreated VS has 
      not been analyzed systematically. The authors undertook this study to investigate 
      changes in contrast enhancement with respect to latency of image acquisition 
      after contrast agent administration. METHODS: The dynamics of contrast medium 
      uptake were evaluated with T1-weighted VIBE MR imaging sequences performed 
      immediately and 1.5, 3.5, 4.5, 9.5, and 11.5 minutes after administration of 
      single dose of Gd in 21 patients with nontreated medium- to large-sized VSs. 
      Signal-to-noise (SNR) and contrast-to-noise ratio (CNR) of tumors were evaluated, 
      and volumes of central nonenhancing areas (NEAs) were determined. RESULTS: The 
      interior appearance of the tumors changed considerably over time. The NEA 
      significantly diminished in size (p < 0.0001, Friedman test) and almost 
      completely disappeared in all but 2 patients. Compared to images at 1.5 minutes, 
      NEA volumes decreased to a median of 36% at 3.5 minutes and 34% at 4.5 minutes, 
      showing smaller changes after that-9% at 9.5 minutes and 3% at 11.5 minutes. 
      Tumor SNR and CNR increased over time. The maximum change in the median values 
      for SNR and CNR were a 72% increase and 117% increase, respectively; both 
      occurred at 1.5 minutes after Gd administration. CONCLUSIONS: Contrast 
      enhancement in VS MR imaging varies according to the duration of the delay 
      between contrast agent administration and image acquisition. Postradiotherapy 
      changes in contrast enhancement of VS can therefore not be attributed only to 
      effective radiotherapy. So-called "loss of central contrast enhancement" may be 
      falsely detected because of timing. A standardized protocol with defined timing 
      of image acquisition may increase comparability of contrast uptake in VS.
FAU - Rampp, Stefan
AU  - Rampp S
AD  - Department of Neurosurgery, University of Halle-Wittenberg, Halle, Germany.
FAU - Scheller, Christian
AU  - Scheller C
FAU - Prell, Julian
AU  - Prell J
FAU - Engelhorn, Tobias
AU  - Engelhorn T
FAU - Strauss, Christian
AU  - Strauss C
FAU - Rachinger, Jens
AU  - Rachinger J
LA  - eng
PT  - Journal Article
DEP - 20100604
PL  - United States
TA  - J Neurosurg
JT  - Journal of neurosurgery
JID - 0253357
RN  - 0 (Contrast Media)
SB  - IM
MH  - *Contrast Media
MH  - Humans
MH  - Image Enhancement/*methods
MH  - Image Processing, Computer-Assisted/methods
MH  - Magnetic Resonance Imaging
MH  - Neuroma, Acoustic/*pathology
EDAT- 2010/06/08 06:00
MHDA- 2011/03/11 06:00
CRDT- 2010/06/08 06:00
PHST- 2010/06/08 06:00 [entrez]
PHST- 2010/06/08 06:00 [pubmed]
PHST- 2011/03/11 06:00 [medline]
AID - 10.3171/2010.5.JNS10307 [doi]
PST - ppublish
SO  - J Neurosurg. 2011 Feb;114(2):394-9. doi: 10.3171/2010.5.JNS10307. Epub 2010 Jun 
      4.