Objectives  Macular telangiectasia is a group of uncommon, idiopathic, retinal vascular abnormalities affecting the retinal capillaries in which irregular capillary dilation and incompetence occur in the macula with or without vascular changes in the retinal periphery. There are three groups of the condition. The macular telangeictasia type 2 (MacTel Type 2) is the most common type. The diagnosis is often missed due to subtle nature of the early findings. The purposes of the study are to identify the causes of the disease, to raise its profile and to search for treatments.
Methods MacTel project was established in 2005 with a team of scientists and clinicians. The project is a comprehensive, international research collaboration of basic scientists, geneticists and clinicians (MacTel Research Group) to study MacTel Type 2.

The clinical study is conducted in up to 25 sites in the United States, Europe, Australia and Israel including Moorfields Eye Hospital, University of Bonn and University of Sydney. Patients are followed up every 12 months. Clinical data including medical and ocular history, best correct LogMar visual acuity, full ophthalmic examination, Optical coherence tomography, autofluorescence scan, colour fundus photography, blue light reflectance, microperimetry, fluorescein angiography and NEI-VFQ are collected. Blood samples are collected for general health tests and genetic analysis.
The laboratory research projects are conducted in Script Clinic USA, Institute of Ophthalmology London, Columbia University of New York and Save Sight Institute, Sydney to study cell-based therapies, to conduct histology and biochemistry study, to analyses genetic abnormality, to conduct proteomics study and to develop MacTel animal models.
Results The clinical study has enrolled more than 500 patients and over 200 family members. Significant progress has been made on identifying the medical and phenotypic characteristics of MacTel Type 2 and the prospects for beginning pilot studies and clinical trials in the near future is promising.

The laboratory study also provides pathological and genetic evidences of the MacTel type 2. Several animal models are established for investigating the mechanisms of the disease.
Conclusion The current international collaboration of the MacTel type 2 study has provided unique study data and new insight for the better understanding of this disease. It also provides a comprehensive patient resources and the fundamental information for the patient care and treatment.