Dr Howard Ball – Male


Born and educated in Zimbabwe, Dr Ball studied medicine in Cape Town working locally following qualification. On arriving in Cornwall, he joined the vocational training scheme for GPs in 1988 and became a part-time partner at Probus in 1992. He combined this with part-time work as a hospital assistant in Child Psychiatry for 4 years before becoming a full-time GP. Dr Ball’s clinical interests include asthma, respiratory disease and psychiatry. He is also involved in the training of undergraduates and registrars. Dr Ball was fully accredited as a GP trainer in January 2008.

When not at work he enjoys time with his wife and three children, cycling and kayaking. He also enjoys barbeques, red wine and swimming in the summer! Dr Ball is available to see patients Tuesdays afternoons, Wednesdays, and Thursdays.

Mr Gaetan Lin Sin Cho – Male


Known as Mr Guy Lin, he graduated in 1992 having attended Wits University in Johannesburg, South Africa. His medical career then took him to Soweto and Mauritius before settling in England where he undertook surgical training in Exeter. Guy became a member of the Royal College of Surgeons in 2001. Guy also trained as a GP in Exeter, qualifying in October 2004. He joined the Probus partnership in that same year as a GP and part-time surgeon with Probus Surgical Centre, moving to Cornwall with his wife and two children. Guy’s clinical interests lie in orthopaedics, general surgery, dermatology and joint injections. He participates in Probus Surgery’s training commitment as a supervisor for the Peninsula Medical School students. He also offers an Implanon service (contraception).

Mr Lin is available to consult patients on Mondays, Tuesdays, and some Thursday mornings. He operates on the rest of the week, including performing his responsibilities as clinical director of Probus Surgical Centre.

Dr Rawlins Murthy – Male


Born and educated in India, he studied Medicine in Nepal and has been working as a doctor in the NHS since 2005. After qualifying he started training in the field of Surgery, but after a placement at Probus Surgery decided to change his career path to become a GP. His clinical interests are eldercare medicine (old age), psychiatry, urinary and prostate problems in men, Musculoskeletal, Orthopaedic and Surgical diseases. Dr Murthy has since joined the Surgical Centre to perform vasectomies. He is also involved with improving child protection policies at the practice. He enjoys playing cricket and is a keen amateur photographer.

Dr Murthy is available for clinics all day Mondays, Tuesdays, Wednesdays and undertakes surgical work on Thursdays.

Dr Simon Purchas – Male


Dr Purchas is one of the full-time GP Partners at Probus Surgery/Probus Surgical Centre, having joined the practice in 2003. He enjoys the full breadth and depth of modern General Practice and, whilst based at Probus, also holds clinics at our smaller branch surgeries in Tregony and Summercourt. Dr Purchas is an Honorary Fellow of the Peninsula Medical School and is involved with teaching their medical students. He is also a GP trainer and works with and supervises the GP trainees we have at the practice. Originally from the West of the County, Dr Purchas is married with four children.

Dr Purchas is available to see patients Mondays, Tuesdays, Thursdays and Fridays.

Dr Kayleigh Smithson – Female

[2012] MBBS MRCGP PGDipDerm

Dr Kayleigh Marie Smithson was born in Yorkshire and trained at the Hull York Medical School. After completing her Registrar year at Probus Surgery, she stayed with the team and went on to become a GP Partner in 2019.

Dr Smithson completed a Diploma in Practical Dermatology gaining a distinction with Cardiff university in 2020 and carries out regular skin and cryotherapy clinics.  She is also the Dispensary and Medications Lead and has special interests in Acute medicine, joint injections, sexual health and mental health. She enjoys teaching and is a trainer for new GP registrars and medical students.

Outside of work Dr Smithson is a big fan of fashion and music, playing guitar and piano and following dance music. She also enjoys long walks with her cocker spaniels.

Dr Smithson is available to see patients on Mondays, Tuesdays, Wednesdays, and Thursdays.

Dr Grace Moon – Female


Dr Moon graduated from the University of Birmingham in 2004. Soon after qualifying she moved to Brisbane, Australia where she worked in Emergency Medicine. She then returned to Cornwall, her home county, to train as a GP. Dr Moon’s special interests include family planning, women’s health, and young people’s health. Dr Moon lives with her husband and 2 children. They enjoy exploring Cornwall by sea kayaking and coastal walking.

Dr Moon is available to see patients on Wednesdays and Fridays.

Dr Sarah Keast – Female


Dr Keast graduated from Imperial College (based at St Mary’s, Paddington) in 1999. Having completed GP training in London she moved back home to Cornwall in 2003 where she has practiced as a GP since then. Dr Keast currently works as a half-time GP in Probus, alongside other roles in the Cornwall 111 Out of hours service and as a GP Appraiser and GP Mentor for other GPs across Cornwall. She is also a member of the Local Medical Committee and works with medical students. Clinical interests include women’s health and Diabetes. She lives with her husband and 2 teenagers and balances medicine with musical interests and various outdoor exercise activities and is always happy when pottering in the garden.

Dr Keast is available to see patients on Thursdays and Fridays.

Dr Lavanya Muthaiyan – Female


Dr Muthaiyan is originally from Chennai, India. She moved to Cornwall in 2004 and worked with many specialities at Royal Cornwall Hospital Treliske from 2005. She has a special interest in respiratory medicine and gained 2 years’ experience as a respiratory registrar before she completed her GP training. Dr Muthaiyan enjoys spending time with her two lovely children. She also enjoys Indian cooking and cleaning.

Dr Muthaiyan is available to see patients on Monday, Wednesdays, and Fridays.