RADIOLOGY—TECHNICAL ARTICLE
Last fluoroscopy hold in paediatric fluoroscopy: Dynamic
capture of physiological events and a potential for radiation
exposure time reduction
Michalle Soudack,
1
Aviv Hirschenbein,
2
Jacob Sosna,
3
Ehud Dafne
2
and Ahuva Engel
4
1
Pediatric Imaging, Edmond and Lily Safra Children’s Hospital, Tel Hashomer,
2
CMT Medical Technologies, Yokneam,
3
Department of Radiology,
Hadassah Hebrew University Medical Center Organization, Jerusalem, and
4
Department of Diagnostic Imaging, Rambam Medical Center, Haifa, Israel
M Soudack MD; A Hirschenbein MD;
J Sosna MD; E Dafne PhD; A Engel MD.
Correspondence
Dr Michalle Soudack, Pediatric Imaging,
Edmond and Lily Safra Children’s Hospital, Tel
Hashomer 52621, Israel.
Email: michalle.soudack@sheba.health.gov.il
Conflict of interest: None.
Submitted 17 May 2011; accepted 24 May
2011.
doi:10.1111/j.1754-9485.2011.02322.x
Summary
The purpose of this study was to retrospectively evaluate last fluoroscopy hold
(LFH) in paediatric fluoroscopy. LFH is a software program that enables
dynamic storage of last fluoroscopy sequences. A hundred and ninety-four
paediatric patients underwent 215 fluoroscopy examinations during a
14-month period. LFH was employed to review an equivocal finding, when last
image hold did not provide an adequate diagnostic image or when a physi-
ologic dynamic event was too fast or did not last long enough to capture. LFH
was used in 29% of the examinations. The Institutional Review Board
approved this study and waived informed consent.
Key words: fluoroscopy; paediatric imaging; radiation protection.
Introduction
There is substantial evidence that paediatric patients are
more sensitive to ionizing radiation than adults.
1–3
There-
fore, all radiologists must adhere to the ‘as low as
reasonably achievable’ (ALARA) principle. Fluoroscopic
studies are performed for the diagnosis and follow-up of
numerous paediatric disorders and, in many cases, have
no adequate and acceptable nonionizing alternative.
Fluoroscopy units are equipped with various devices to
assist in radiation reduction. One of these devices, fluoro
loop or last fluoroscopy hold (LFH), stores the last fluo-
roscopy sequence for instant review and storage to the
picture archiving and communication system (PACS)
and, in many situations, obviates the need for repeat
fluoroscopy, thereby potentially reducing the overall
radiation exposure time. The goal of this investigation
was to evaluate this feature in paediatric fluoroscopy
examinations.
Methods
LFH
LFH consists of a cyclic-buffered memory embedded in
the radiography and fluoroscopy system, which stores
the last 250–500 images of any fluoroscopy run. It does
not require presetting. It is activated at any time by
pressing a key on the system panel keyboard. Images
are displayed one at a time with each subsequent key-
press beginning from the last of the sequence. Any frame
can be stored, edited and sent to the PACS. LFH is
automatically disengaged when fluoroscopy is resumed.
Patients
The Institutional Review Board approved this retrospec-
tive study and waived informed consent. This study
included 215 consecutive paediatric fluoroscopy exami-
nations during a 14-month period performed by the
same paediatric radiologist (MS) or performed by a resi-
dent supervised by the paediatric radiologist (MS), all
equally aware of the LFH functionality.
All studies were performed with a SmartSpot PrimaX
Digital photospot system (Yokneam, Israel).
There were 194 patients, 83 male and 111 female
aged 3 days–16.4 years, mean 2.7 years at time of
examination. Examinations included 158 (73.5%)
voiding cysto-urethrographies (VCUGs), 47 (21.9%)
upper gastrointestinal (UGI) contrast studies, four
(1.8%) single-contrast enemas, three (1.4%) small
bowel studies, two (0.9%) linograms and one (0.5%) air
enema for intussusception reduction.
Journal of Medical Imaging and Radiation Oncology 56 (2012) 93–95
© 2012 The Authors
Journal of Medical Imaging and Radiation Oncology © 2012 The Royal Australian and New Zealand College of Radiologists 93