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Posterior vitreous detachment

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Involves separation of the posterior vitreous from the retina as a result of vitreous degeneration and shrinkage.

Age related event.

Prevalence in the general population is 24% in adults age 50 of 59 years and up to 87% among those aged 82 to 89 years (Hickichi, T).

Aside from age other risk factors include myopia, trauma, and intraocular inflammation.

May be asymptomatic, but more often patients report floaters and flashes in the affected eye.

Floaters may persist for months to years in cases of chronic, uncomplicated PVD and without recent change in symptoms are not a cause for alarm.

PVD is an age related process of degeneration and shrinkage of the vitreous.

It is the physiologic  and common in individuals after the age of 40.

Most people develop PVD sometime during their lifetime.

The majority of cases of PVD are benign without long-term complications.

The prevalence for retinal tear complicating PVD is 14% in a meta-analysis (Hollands H).

In meta-analysis men were slightly more likely to have retinal tears in women with a ratio of 1.5:1, and being older than 60 years did not increase the likelihood of a retinal tear, and there was no association with myopia (Hollands H).

In the acute phase of PVD of the vitreous shrinks and detaches from the retina.

Full thickness tears allow fluids to gain entry to the subretinal space, which can lead to separation of the neurosensory layer of the retina from the underlying retinal pigment epithelium, this is ref2242ed to as a retinal detachment.

Retinal detachment results and disruption of photo receptors and can precipitate tissue necrosis.

33 to 46% of untreated retinal tears result in retinal detachment.

Mimicked most commonly by migraine with associated visual aura.

Migraine can be distinguished from posterior vitreous detachment because the aura is bilateral, and involves sensation of colored lights versus white lights seen in PVD, and the evolves over 5-30 minutes before resolution and onset of headache.

Migraine patients have normal visual acuity that is unchanged and a normal ocular examination.

Rarely, occipital lobe disorders with ischemia or infarction, hemorrhage or AV malformation, seizure disorders or malignancy may present with aura.

Most patients with the detached or retinal tear have decreased visual acuity in the affected eye.

The presence of a monocular visual field defect suggests a detached retina is present.

Slit-lamp examination may reveal the presence of vitreous pigment or hemorrhage.

Represent cellular or free melanin in the vitreous that has been released from retinal pigmented epithelium associated with a full thickness retinal tear.

Mydriatic agents to dilate the pupil in patients with possible retinal tears are not contraindicated.

Pupil dilatation may allow the detection of a retinal detachment with vitreous hemorrhage.

Measurement of intraocular pressures are not necessary in the evaluation of flashes and floaters.

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