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Updated: May 5, 2026

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
Retinal venous thrombosis in a young patient with coagulation factor XII deficiency
L Borrego-Sanz1, E Santos-Bueso1, F Sáenz-Francés1
1Unidad de Neurooftalmología, Servicio de Oftalmología, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, España.
Case Report:
A 35-year-old woman, with no relevant medical history, was referred for sudden vision loss in the left eye. Ophthalmological examination showed best corrected visual acuity of 1.0 in the right eye and 0.3 in left eye, with normal anterior pole and intraocular pressure. Fundus examination of the left eye revealed a venous thrombosis in the superior temporal branch, with dilated and tortuous retinal veins. The patient was referred to the hematology unit for thrombophilia study, and was diagnosed with a coagulation XII or Hageman factor deficiency.
Discussion:
The development of retinal vessel occlusions, in patients under 50 years of age, is frequently associated with thrombophilia or hypercoagulability disorders. Factor XII deficiency is a rare condition, and its presence could contribute to a higher risk of thromboembolic events.
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