http://www.hammondopticians.co.uk/wp-content/uploads/2015/09/hammond-opticians-enfield.png 0 0 hammondopticians http://www.hammondopticians.co.uk/wp-content/uploads/2015/09/hammond-opticians-enfield.png hammondopticians2014-03-01 09:12:362014-02-01 16:24:10New way to assess the success of stem cell treatment in eyes
A group of London-based researchers has developed a tool which can be used to assess the outcome of stem cell treatments in patients with a rare eye condition.
The COASTL tool is a scale which measures the biomarkers of a rare disease called limbal stem cell deficiency (LSCD), providing an objective way to measure the outcome of surgical procedures for the first time.
Patients with LSCD can suffer from pain and loss of vision as their corneas are unable to regenerate. The condition is caused by the damage, or death, of limbal stem cells, which renew the surface skin of the cornea.
A key treatment option for patients is a transplant of corneal stem cells, but up until now the success of the procedure has been assessed by the surgeon involved. This meant that results were subjective and open to bias, making it difficult to compare the outcomes of surgery with those of different groups.
Ophthalmologist and lead researcher, Dr Alex Shortt, who is based at the University College London (UCL) Institute of Ophthalmology, said: “It removes a huge source of bias in terms of determining what the real success rates of these transplants are, as it provides objective and unbiased outcome data.” He added: “We aim to use it immediately in upcoming clinical trials in stem cells and clinical disease.”
COASTL was developed through a collaborative effort between researchers at UCL, Moorfields Eye Hospital and the National Institute for Health Research. The eyes of patients are photographed before and after surgical procedures and then measured for a number of key markers for the condition, with severity graded on a scale. This allows clinicians to directly compare the results of surgery done by different groups, and assess them using the same tool.
In a trial of 14 patients with two common forms of LCSD – Aniridia* and Stevens-Johnson Syndrome** (SJS) – COASTL showed that in the first year after the transplant the severity of LSCD decreased and visual acuity increased (VA). However, after this initial 12 month period, symptoms re-emerged and VA declined.
However, although clinical symptoms recurred in some patients, Dr Shortt explained that even three years after the procedure, 30% of patients with Aniridia and 25% of those with SJS saw sustained visual benefits.
Dr Anthony Atala, director of the Wake Forest Institute for Regenerative Medicine and editor of Stem Cells Translational Medicine, said: “A reliable method of obtaining objective outcome data for surgical trials of limbal stem cell deficiency will greatly contribute to the effective evaluation of current and new treatments.”
The tool is ready to use and will be introduced to the Cells for Sight transplantation and research programme, with trials taking place at Moorfields.
Dr Shortt added: “We hope that if other groups use [COASTL] then it will enable us to directly compare our results against theirs and to see whose method of growing the cells, or transplanting cells has the better outcome.”
* Aniridia: This is the absence of the iris, usually involving both eyes
** Stevens-Johnson Syndrome: This is thought to be a hypersensitivity complex that affects the skin and the mucous membranes, for example in the eyes. The most well-known causes are certain medications, but it can also be due to infections. It can be life threatening in very severe cases.