Persistent hyperplastic primary vitreous: diagnosis, treatment and results.

While the great majority of patients with persistent hyperplastic primary vitreous never obtain useful vision, it is encouraging that 18.07% of all the patients in this series did achieve 20/200 vision or better (Table V). In the whole group, 12 of 83, or 14.45%, obtained 20/70 vision or better with treatment. All of these successful results were in eyes with the purely anterior PHPV only. In fact, when looking at the results of the anterior PHPV cases alone, 15 of 21 achieved 20/200 or better, which was 71.4% of the patients with anterior presentation only. In this anterior group, 12 of 21 (57.1%) attained 20/70 vision or better with treatment. The goals of treatment with PHPV should always be kept in mind when confronted with an infant who has this entity. First, an effort should be made to save the eye from glaucoma or phthisis, which are the most devastating results of untreated PHPV. A lensectomy will usually prevent the secondary glaucoma, which results from the lens-iris diaphragm being pushed forward to cause a secondary angle-closure glaucoma. A secondary glaucoma can also be produced from recurrent hyphema, which scars the outflow passageways in the angle. By removing the PHPV membrane and reducing the tractional forces applied to the ciliary body by the membrane, one can lessen the possibility of phthisis. Surgery reduces the centripetal, as well as axial, forces generated by the membrane. The second goal is to produce a black pupil for cosmetic reasons, and the third goal of obtaining useful vision is reasonable to expect if the entity presents with only anterior involvement. Bilaterality, while rare in this series (2:83 cases, or 2.4%), was a very poor prognosis for vision, since both patients had only light perception to hand motion vision in both eyes. With the exception of the eye problems, these two children were otherwise normal in their physical and mental development. No measurable stereopsis or binocularity has been achieved in any of these patients. This was primarily because 100% of the patients had strabismus and secondarily to the fact that in the patients with good surgical results, aggressive and prolonged patching may have precluded the development of binocular vision. Two patients have uncontrolled glaucoma with only light perception vision. Both of these patients are comfortable and pain-free. Two patients have, in time, developed phthisis and wear a cosmetic shell. No cases have required enucleation in this series. (The pathological specimen from Figs 1 and 2 represents an enucleated eye during my residency.) Two patients developed an extensive cyclitic membrane after surgery, which completely occluded the pupillary space. Both patients had originally undergone extensive membrane removal of their PHPV with the production of a nice clear pupillary space. The first patient developed the cyclitic membrane only 3 weeks after the original surgery. A second surgery has been successful in clearing the pupillary opening, but the patient has only hand motion vision at 1 foot due to amblyopia. The second patient had been fitted with a gas-permeable hard contact lens after original surgery for an anterior PHPV. An extensive cyclitic membrane developed 4 months later and required a secondary procedure to clear the pupillary space. The patient's pupillary space has remained open after this second procedure, and the patient is currently wearing a contact lens and undergoing amblyopia therapy. The most important factor in the prognosis of patients with persistent hyperplastic primary vitreous is the extent of the membrane. Families should be told that if their child has only an anterior presentation, then surgical and amblyopia therapies offer a good chance for useful vision. Patients with a combination of anterior and posterior PHPV, or patients with only a posterior PHPV, should be advised that there is a reasonable opportunity to save the eye from glaucoma and phthisis, but that useful vision is usually not