46
could be used to better define the location or be used directly to assist with aspira-
tion or biopsy of the area. Stains and culture of the obtained material could lead to
appropriate antimicrobial treatment with expected better subsequent outcomes with
the HSCT. The radionuclide assays were improved during the 1980s, as computer-
ization improved, and MR imaging became available. The information captured on
the scanner plate could be superimposed on the CT scan or MR image in a
3- dimensional fashion, allowing for better colocalization of the putative site of
infection, thus resulting in easier attempts for aspiration or biopsy of the sites.
Currently, PET scanning or SPECT scanning have more-or-less supplanted the pre-
viously used radionuclide scans, since greater resolution can be achieved and better
localization of a potential infected site can be found [ 10 ].
In summary for patients with immunodeficiency preparing to undergo HSCT
there is risk for hidden infection to be present, especially if neutropenia is present,
or fevers have been occurring. Identification of a site of potential infection with the
most appropriate currently available imaging procedure, and then using aspiration
or biopsy of the site to determine the organism(s) present, with subsequent appro-
priate antimicrobial therapy, can result in better HSCT outcomes.
3.3 Role of Radio-Labeled MIBG Imaging in Children
with Neuroblastoma
(^123) I-MIBG is used for diagnostic purposes in patients with neuroblastoma. It is usu-
ally used as a whole-body scan, but can be used to focus on a particular area when
combined with CT scanning. It is often usually used to demonstrate 2-dimensional
images, (scintigraphy) but can be 3-dimensional when used in combination with
SPECT scanning.
3.4 Ongoing Clinical Trials with MIBI
There are presently 97 experimental clinical trials (active and open) exploring the
roles, uses, indications and toxicities of MIBG treatment (reference=https://www.
clinicaltrials.gov/ct2/results/browse?term=MIBG&brwse=cond_cat). The studies
are open around the world (58 in USA, 14 in Canada, 21 in Europe, 3 each in the
Middle East, and the Pacific, 2 each in East Asia and South America, and 1 in North
Asia). Of these studies, 48 are specifically for patients with neuroblastoma. Other
MIBG studies are for patients with pheochromocytoma, autonomic dysfunction,
myocardial sympathetic denervation, PVC ablation, cardiomyopathy, and others.
Of the 48 studies presently registered at ClinicalTrials.Gov, 18 are open and a ccruing
new patients with a known status. The trials have been divided into two catego-
ries (1) diagnostic use and (2) therapeutic use. This section covers the diagnostic
use of the MIBI scanning.
M. Atiq et al.