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VITREOUS DETACHMENT AND VITREOUS OPACITIES
Nikhita Jacob, Third year
ANATOMY and PHYSIOLOGY
• Transparent, gelly-like• 4/5• 4ml• Anterior depression – hyaloid fossa or burger’s space• Periphery – dense cortex• Center – liquid • Viscosity
• Mechanical function – shape• Nutrients to lens and retina
Attachments
• Vitreous base – Ora serrata (4mm)• Behind lens- Hyaloid fossa (firm at young age)• Optic disc• Macula • Blood vessels
Vitreous components
• Refractive index • Water – 98%• Fine collagen fiblrils – cortex• Large amount – hyaluronic acid, amino acid,
soluble proteins, salts and ascorbic acid• Cloquet’s canal – 1-2mm wide• With age – volume of gel liquid content
Vitreous detachment
• Complete / partial• 3 forms: -Posterior -Anterior -Basal• Most common
Etiology
• Synchysis • Begins posteriorly – attachment undeveloped• Strong forces – anterior detachment and basal
detachment
Posterior vitreous detachment
• Separation – cortex from retina – posterior to base• PVD with synchysis and synersis – common above
65years• Common with senile liquefaction - Develops a hole
– hyaloid membrane – collects between membrane and internal limiting membrane of retina – PVD upto base with synersis of remaining vitreous gel
• More – aphakics and myopes
• Symptoms: - Flashes - Floaters - Decreased visual acuity - Cob-web like appearance - appearance of hair-like structure• Signs: - Biomicroscopic examination reveals - Synchysis - Weiss ring or Fuch’s ring – glial tissue
• Diagnostic criteria: - Requires examination of fundus - Ultrasound examination – vitreous
hemorrhage or lens opacification
Detachment of vitreous base and anterior vitreous
• Usual etiology – blunt trauma – anterior retinal dialysis – crystalline lens dislocation
• Complications: - Retinal breaks - Vitreous hemorrhage - Retinal hemorrhage - Cystoid maculopathy
• Treatment: - symtoms resolve – complete detachment - complications – treatment
Vitreous opacities
• Any relatively non-transparent structure – opacity – floaters
• Common conditions associated with vitreous opacity:
-Muscae vollitantes-Inflammatory vitreous opacity-Vitreous aggregates and condensation with
liquefaction-Amyloid degeneration-Asteroid hyalosis-Synchysis scintillans-Red cell opacities-Tumor cell opacities
Muscae vollitantes:• Physiological – residues – hyaloid vasculature• Fine dots and filaments• Drifts in and out of visual field
Inflammatory vitreous opacities:• Exudates – anterior/posterior uveitis• Pars planitis• Pan uveitis• Endophthalmitis
Vitreous aggregates and condensation with liquefaction:
• Commonest cause• Collagen fibrils – senile, myopic, post-trauma,
post-inflammation
Amyloid degeneration:• Amyloidosis• Amyloid material – thyroid, pancreas, heart,
vitreous• Bilateral
• Pathophysiology: -originates – retinal vessel walls – cloudy
margin• Symptoms: -Diplopia -Diminished vision• Signs: -External ophthalmoplegia -Vitreous opacities -Retinal hemorrhage -Exudates
Asteroid hyalosis:• Causes: -Genetic inheritance -Diabetes -Hypercholestrolemia• Pathophysiology: -Calcium containing lipid complexes –
collagen fibrils – throughout vitreous• Age: Elderly people• Sex: Both
• Symptoms: -Mostly asymptomatic• Signs: -Unilateral -Small, white rounded bodies – vitreous
gel – ophthalmoscopy• Treatment: - If vision affected – vitrectomy
Synchysis scintillans: (cholesterolosis bulbi)• Causes: - Degeneration condition - Damaged eyes – trauma, vitreous
hemorrhage or degenerative disease in past – end stage – pathogenesis unknown
• Symptoms: -Mostly asymptomatic
• Signs: - Small, white, crystalline bodies – cholesterol
accumulation. - Vitreous-liquid-crystals sink to bottom-
stirred up – eye movement -Beautiful shower of golden rain –
ophthalmoscopy
• Treatment: Not required.
Red cell opacities: vireous hemorrhage – leftouts of massive
vitreous hemorrhage
Tumor cell opacities: seen as free floating opacities –
retinoblastomas and reticulum cell sarcomas
Thank you