What tests might I have?
Structural Brain and Spinal Imaging
A fairly standard test for most patients would be an MRI scan of the brain and if indicated the spinal cord. MRI uses magnetic waves and there is therefore no radiation exposure. MRI at the Nuffield in Derby is carried out onsite and can usually be done within a few days and sometimes on the day of assessment for urgent cases. Having an MRI scan requires you to lie on a platform which then slides into a tunnel. MRI scans can be noisy and for claustrophobic patients, can present some difficulty. They are completely painless. For claustrophobic patients, we can arrange a scan in an “open” MRI magnet at Heath Lodge Hospital in Solihull. For MRI scans done at the Nuffield, I will review the images with you at your follow-up appointment and you are welcome to request images to be transferred to a CD-ROM disc for your personal records.
Other types of scan
Some patients need other types of brain imaging. Most of these other scans involve the intravenous injection of a radioactive tracer and as such are associated with a small dose of radiation. For some scans, such as DaTSCAN, the radiation is equivalent to a few CT scans and is cleared from the body in a week or so through urinary excretion. In general I arrange these scans at facilities local to the patient. For patients living in Derby this will be at the Royal Derby Hospital Nuclear Medical department, and for Nottingham patients at the In Health PET centre at the City Hospital. Radionuclide scans that I might order would include HMPAO SPECT or FDG PET for memory/neurodegeneration evaluation and DaTSCAN for parkinsonian cases. In some cases I organise a CT scan. CT scans do involve a small dose of radiation as they are essentially X-ray based scans. I might organise a CT if I want a detailed evaluation of the vessels of the brain or to exclude cancer in the body cavities that might have spread to the brain.
Nerve conduction/EMG studies (NCS/EMG) are electrical studies of the nerves and I organise these if I want to look for evidence of nerve or nerve root damage. I refer patients to colleagues either at Derby Nuffield or at the Royal Hallamshire Hospital in Sheffield. NCS/EMG tests can be slightly painful as they involve a small electrical shock and the EMG needles might hurt as they are inserted into muscle. Patients on warfarin cannot have EMG but can still have limited NCS. Another common neurophysiological test is electroencephalography (EEG)- this test is done to assess the brain waves and is painless. A rubber electrode cap is placed over the head and measurements are carried out for about an hour. This test is useful in the evaluation of some cases of epilepsy and memory difficulty. Rarer neurophysiological tests that I might order include visually evoked potential studies (VEP) of the eyes, somatosensory evoked potentials (SSEP) for the sensory pathways and sometimes central motor time conduction studies (CMCT) of the motor pathways.
Rarely some patients need to have analysis of their cerebrospinal fluid (CSF) by placement of a lumbar picture needle under local anaesthesia into their lower lumbar (back) area. This test would require a patient to come into the day case unit of the hospital. After a lumbar puncture, patients are advised to lie flat for a few hours in a hospital bed and drink copious amounts of fluid to avoid a post-lumbar puncture headache. We normally advise somebody collects you to take you home after a lumbar puncture as driving might be sore for the first day.
Sometimes I organise blood tests for my patients. Generally these are done at the Nuffield hospital or sometimes by your own GP.