Degenerative myopia

Degenerative myopia

 Myopia is common refractive disorder and is regarded as physiological if <–6D.

 high myopia (>–6D), in whom the axial length may never stabilize (progressive or pathological myopia) and are at risk of degenerative changes.

 Excessive near work appears to be a risk factor, while increased time outdoors appears protective.

 genetic risk factors may also play a role in high myopia.

Clinical features in Degenerative myopia

 Increasing myopia, decreased VA, metamorphopsia, photopsia (occasional).

 Fundus: pale, tessellated with areas of chorioretinal atrophy both centrally and peripherally

 Breaks in Bruch’s membrane (lacquer cracks) may permit CNV formation, spontaneous macular haemorrhage, and subsequent elevated pigmented scar (Forster–Fuchs spot)

 posterior staphyloma

 lattice degeneration.

 Disc: tilted, atrophy temporal to the disc (temporal crescent)

 Vitreous syneresis; PVD (at younger age).

Other associations: 

• long axial length 
• deep AC
• zonular dehiscence
• PDS
• glaucoma( OAG)

Complications in Degenerative myopia

 CNV (myopia is commonest cause of CNV in young patients)

 macular hole

 peripheral retinal tears

 RRD

 macular retinoschisis. 

NB in Degenerative myopia

 Retrobulbar anaesthesia is contraindicated in Pathological myopia with posterior staphyloma for fear of globe perforation ( topical or peribulbar is an option )

 Pathological myopia is considered fragile eye  and should be treated gently when an operation considered

Significant hyperopia in Degenerative myopia: 

 Any degree of hyperopia sufficient to cause symptoms prompting clinical attention.

 Simple hyperopia is due to decreased axial length or decreased power of cornea, lens, or media. 

 Pathologic hyperopia is due to atypical development, trauma, or disease of the eye (microphthalmia, nanophthalmia, aniridia)

 Functional hyperopia is due to paralysis of accommodation and usually present at birth.

 Drugs, such as cycloplegics, can also cause a transient hyperopia.

 hyeropia classified 

• low Hyperopia <+2.00 
• Moderate +2.00 to +5.00 
• High >+5.00 

 patient presented most commonly, with decreased visual acuity or squinting at near distances specially in kids 
 Hyperopic eye is always considered small crowded eye  with 
• Flat cornea
• Short axial length 
• Small AC with narrow angle
• Thick choroid 
• Small crowded disc ( disc at risk) 

 operating on Hyperopic eye is little bit challenging as working in narrow spaces with high risk of choroidal detachment intra or post operatively.

Degenerative Myopia power point presentations:

Pathological Myopia

https://www.slideshare.net/akulaJayakrishna/pathological-myopia

A brief description about pathological myopia

High myopia and management

https://www.slideshare.net/sabinapaudel/high-myopia-and-management

Degenerative Myopia Videos :

Degenerative Myopia

Degenerative myopia