By Dr Subramaniam Nagasayi, Consultant Care of Elderly, Withybush General Hospital

Parkinson’s Advanced MasterClass 36A, November 2019


Hywel Dda University Health Board (UHB) consists of four district general hospitals serving South-west Wales, historically each with its own movement disorder services. Patients with suspected movement disorders including Lewy body dementia are referred predominantly to geriatricians but sometimes to neurologists and old age psychiatrists based on the pre-dominant symptoms at presentation.

The diagnosis of parkinsonism, is predominantly clinical, based on Brain bank criteria. However 123I FP CIT single photon emission computed tomography (SPECT/) or dopamine uptake scans (DAT) are used in uncertain situations to differentiate parkinsonism syndromes and LBD from other dementias.

With recent pressures in the health board due to a variety of factors such as retirements of consultants, PD nurse specialists, failure of recruitment etc there is a move to amalgamate movement disorder services. There has been a recent trend of DAT scans requested by generalist colleagues which has led to an increased number of referrals to the specialists based on positive DAT scans results rather than clinical criteria alone. This practice is not in concordance with NICE guidelines and leads to unnecessary variations of practice with increased costs and false positive diagnosis.

This retrospective study would help us understand better, the current practice and thereby advise of necessary changes to be incorporated in standardization of practice across the health board.


DAT scan requests over 1 year June 2018 to June 2019 were reviewed:

  1. Number of DAT scans performed
  2. Who made the requests—movement disorder specialists OR generalists?
  3. What was the pre-DAT scan diagnosis?
  4. Did the DAT scans alter the diagnosis?


  1. There has been a 6-fold increase in DAT scan requests (period 2010-2019) at 111.
  2. Most are requested by movement disorder specialists (101- 90%). However 10%were requested by non-specialists.
  3. 14/111 requests did not match NICE guidelines and 3/111 were rejected due to poor patient tolerance.
  4. In 77 patients (~70%), diagnosis and hence management did not change.
  5. We presented the data in our regional PD group meeting with plans for consideration of separate DAT request forms, update nuclear medicine list of movement disorder specialists in the health board, patient information leaflet pre-scan and education.

We wish to improve referral system and timing for new PD patients which may reduce unnecessary DAT scan referrals. We wish to undertake a re-audit in a year’s time after implementing above changes.