As part of the scan a special contrast agent will be injected into a vein so that the 
tumor can be better seen. A small proportion of people develops short-lived reactions during 
the administration including nausea, headache, hot flashes, and heart palpitations. These 
symptoms usually resolve spontaneously within minutes. A smaller group of patients are 
actually allergic to the agent and may develop a rash, hives, respiratory difficulty, and in 
extreme cases pulmonary and cardiac arrest and death. You will be closely monitored and if 
an allergic reaction develops, you will be promptly treated with epinephrine and breathing 
assistance if necessary. Both therapies are immediately available in the room where the 
brain scan will be performed. 
Patients at risk for injury from MRI are those with pacemakers, metal devices, or shrapnel 
fragments in their bodies. Welders and metal workers are also at risk for injury because of 
possible metallic foreign bodies in the eye. If you are at risk for injury by MRI scanning, you 
will undergo CT scanning instead. 
Risk of Surgery: 
The surgical risk depends on the preoperative condition of the patient, the nature of the 
operation, and the location and size of the tumor. Known risks associated with brain surgery 
include: hemorrhages, deterioration of neurological functions (such as weakness in the arm 
and/or leg, loss of sensation over parts of your body, and partial or complete loss of 
functions related to communication such as speech and comprehension, and other functions 
related to intellectual capacity, memory, etc.), infection and death. The relative risk will be 
discussed with you in accordance with your condition, specific findings and planned surgical 
procedures. 
Risk of the Virus and Gene Transfer: 
Even though the virus that is injected cannot cause infections it is possible that events 
could occur within the cells that would permit the virus to change and become infectious. If 
that were to happen there is a possibility that you may develop an illness similar to 
meningitis or viral infection of the brain. Gene transfer using similar vectors has been used 
in patients with the lung disease cystic fibrosis. To date there are no reports of this type of 
virus vector changing to an infectious virus in either laboratory animals or in humans. We 
believe these vectors are safe and are not a threat to other people or to society. 
It is possible that the virus will damage normal brain tissue around the tumor if it leaks 
out of the tumor site. In laboratory experiments virus was injected into the brains of baboons 
at two different doses with and without Cytovene®. One dose was the same as the highest 
we will test in humans, we call it the low dose, and the other was 20 times higher, the high 
dose. When baboons were injected with high doses of virus and treated with Cytovene® 
the animals died or became so sick that they were put to sleep. Injection of the high dose of 
virus into brain tissue with no Cytovene® caused local, irreversible damage soon after the 
injection. Lower doses, similar to what we will be injecting into your tumor, caused local 
damage at the site of injection that appeared to be healing 6 weeks after injection. It is not 
known what the long-term consequences are going to be from injecting this virus into tumors 
such as yours. We believe that some of the surrounding blood vessel cells will take up the 
vector, but the number is too small to result in significant adverse side effects. It is possible 
that bleeding and neurologic symptoms (headache, convulsions, stroke) may develop with 
Cytovene®. It is also possible that the virus will leak out of the brain and will be spread 
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