The High-Resolution Microscopy Coil MRI For Orbit: Preliminary Study

PartⅠThe High-Resolution Microscopy Coil MRI for orbit: technical studyObjective: To select suitable coil of two different diameter of microscopy coil, for evaluate the micro-coil MR imaging of the feasibility of the eye, and to depict minute structure in the eye and orbit with HR-MR. Methods :A phantom with CuSO4 .5H2O for Philips was scanned with 47mm and 23mm microscopy coil in 1.5T systems by Philips. Signal of different depth was compared by T1WI and T2WI imaging by two coils. 47mm microscopy coil was found an ideal coil for achieve orbit HR imaging. Ten healthy volunteers (20 eyes) received 47mm micro-coil MR exam. The examination protocol included T1- weighted spin-echo images and T2-weighted turbo spin-echo images, Slice thickness 2mm, spacing 0.2mm. Results: The micro-coil MR imagings can clearly show the fine structure of orbital and eye, such as retina, sclera and choroid. Tenon's capsule is surrounding the sclera. The iris and zonules of the lens are visible. The inner canthal ligament, lateral palpebral ligament and Müller muscle are also clearly depicted .Conclusion: MR microscopy coil imaging can show subtle anatomy of the eye . It is a new technology for improve the diagnostic accuracy and surgical planning.PartⅡMicroscopy Coil for MRI of eye shape in myopia: compared with emmtropia.Objective: myopia is one of the most important causes of visual impairment among children and adults, and it likely affects east Asians. We studied ocular expansion models of Chinese myopia through axial, vertical, and horizontal eye dimensions in myopia and emmetropic eyes by high resolution Magnetic Resonance imaging. Methods :A total of 37 participants (19 emmetropia, 16 low myopia,20 moderate myopic, 19 high myopia) were included in the study. Age arranged 20 to 37 years. All eyes were classified as high myopia(>-600D), moderate myopia(-300D < M≤-600D),low myopia(-50D < M≤-300D)and emmetropia(-50D0.05). There was no significant correlation between anterior champer depth, lens thickness and M in all the groups. Conclusion: The three dimensions of myopia were significantly longer than that of emmetropia with the increased vitreous .But height and width of low myopia no significant change compared with emmetropic.PartⅢClinical application of HR-MRI in ophthalmology: preliminary studyObjective: To study the value of micro-coil MR imaging in the diagnosis of ocular disease. Methods :A total of ten people with ocular disease was included in this study. Mean patient age was 32.3 (8–59) years. Imaging was performed using MRI micro-coil and conventional head coil to evaluate the different imaging techniques. Results: The lesion could be clearly depicted in all patients (100%) with microscopy coil and in 7out of 10 patients (70%) with head coil. The irido-angle contact and the cup of the optic nerve head could be diagnosed in angle closure glaucoma patient with MR micro-coil and could not be found with head coil. The small mass of orbit and eyelid were well depicted with micro-coil MR imaging and hardly displayed with head coil. Conclusion: High-resolution MRI of the orbit using a 47-mm microscopy coil is a promising method to accurately characterize the normal anatomy of the orbit and depicting its lesions in detail .And it can facilitate diagnosis and pre-operative planning. neuro-ophthalmic. Head coils are mainly beneficial for imaging the eye in the context of the head. How to choice coil of scan strategies depend on characteristic of disease.