<prompt> Which of the following does not show calcification?Persistent hyperplastic primary vitreous PHPVOptic nerve DrusenChoroid osteomaRetinoblastoma  <response>: Ans. a. Persistent hyperplastic primary vitreous Ref: stylefont-size: 1.04761904761905em; font-family: Times New Roman, Times, serifCauses of Calcification of the GlobeRetinal:DrusenRetinoblastomaRetinocytomaTuberous sclerosis TSEpiretinal membranesRetrolental fibroplasia retinopathy of prematurityCoats diseaseRetinochoroidalChorioretinitis: most commonly following ToxoplasmosisChoroidalChoroidal osteomas: more common in patients with tuberous sclerosisChoroidal angiomas : occasionally calcifySclerochoroidal:Metastatic calcification: hyperparathyroidism, pseudohypoparathyroidism, renal tubular acidosisDystrophic calcification: Phthisis bulbiPersistent Primary Hyperplastic Vitreous Persistent Fetal Vasculature Syndrome PFVUncommon congenital ocular anomaly in which the hyaloid vasculature system and primary vitreous fail to involute or regressUsually unilateralAssociations of Bilateral PHPVTrisomy 13 Patau syndromeNorries diseasesWalker Warberg syndromeClinical Presentation:Typically presents with unilateral leucokoriaTypically associated with mild microphtalmosAbnormality may be confined to anterior segment or posterior segmentPersistent Primary Hyperplastic VitreousAnterior PHPVPosterior PHPV Abnormality is confined to anterior segment Often involves the lens Typical Presentation:- Unilateral leucokoria Signs and complications:- Retroiental mass into which elongated ciliary processes are inserted- Cataract- Shallow anterior chamber and angle closure glaucoma- Recurrent intraocular hemorrhage- Microphthalmia Treatment:- Vitreoretinal surgery in selected early cases to salvage vision- Abnormality is confined to posterior segment- Lens is usually clear- Typical Presentation:- Unilateral leucokoria, strabismus and nystagmus- Signs and complications:- Adense white membrane or a prominent retinal fold extension from the optic disc to ora serrate- Pre-retinal membrane- Tractional retinal folds and tractional retinal detachment- Retinal dysplasia and optic nerve hypoplasia- Microphthalmia Treatment:- Not possible 