QuizWise 19

1. The Vitreomacular traction was defined as vitreous attachment found no further than ______from the fovea and causing micro structural changes in the retina

a.   1,500 µm  

b.   2500 µm

c.    1000 µm

d.    500 µm

2. Vitreoretinal proliferations are seen in 

1. Diabetic retinopathy 
2. Retinal detachment
3. Ocular inflammation
4. Retinal tears
5. All of the above

3. A focal vitreous attachment at macula exerts

1. Greater tractional force 
2. Greater stress
3. Lesser tractional force
4. Lesser stress
5. a and b
6. b and c 

4.   Visual outcome after vitrectomy for VMT is correlated with 

1. Preoperative vitreomacular structure
2. Duration of symptoms
3. Preoperative CMT (Central Macular Thickness)
4. All of the above

5. Vitreomacular traction can be differentiated from vitreomacular adhesion by 

1. Intra retinal cysts
2. Photoreceptor loss
3. a and b
4. Metamorphopsia

Answers:

1. a 

Vitreomacular traction was defined as vitreous attachment found no further than 1,500 µm from the fovea and causing microstructural changes in the retina in this area.

Odrobina et al. Evaluation of Vitreo Macular Traction disorder in Spectral Domain Optical Coherence Tomography, The journal of Retinal and Vitreous diseases 2011   volume 31. doi: 10.1097/IAE.0b013e3181eef08c

2. e

Vascular diseases, diabetic retinopathy, retinal detachment, ocular inflammation, and retinal tears can cause vitreoretinal proliferations.

Odrobina et al. Evaluation of Vitreo Macular Traction disorder in Spectral Domain Optical Coherence Tomography, The journal of Retinal and Vitreous diseases 2011   volume 31. doi: 10.1097/IAE.0b013e3181eef08c

3. e 

Stress is an internal resistance, or counterforce, of a material to the distorting effects of an external force or load. Stress can be equated to the force (F) applied per cross-sectional area (A) perpendicular to the force: F/A. The magnitude of the stress is directly proportional to the tractional force concentrated at the macula. Greater tractional force is expected in eyes with a focal attachment because the angle of the vector is more perpendicular to the affected retinal surface. 

Sonmez et al. Vitreomacular traction syndromeand Visual Outcomes, The journal of retinal and vitreous diseases 2008   volume 28. doi:10.1097/IAE.0b013e31817b6b0f

4. d 

Visual outcome after vitrectomy for VMT is correlated with preoperative vitreomacular structure, duration of symptoms, and preoperative CMT (Central Macular Thickness). 

Sonmez et al. Vitreomacular traction syndromeand Visual Outcomes, The journal of retinal and vitreous diseases 2008   volume 28. doi:10.1097/IAE.0b013e31817b6b0f

5. c

Intraretinal cystoid spaces were defined as the cystoid spaces in the inner and/or the outer retinal layers appearing secondary into the tractions acting on the retina through the attached vitreous body. The traction induced on the retina through the attached vitreous body causes changes in its inner layers and also in its outer layers (photoreceptors). So, vitreomacular traction can be differentiated from vitreomacular adhesion by intra retinal cysts and photoreceptor loss. Metamorphopsia is seen in both vitreomacular traction and vitreomacular adhesion.

Odrobina et al. Evaluation of Vitreo Macular Traction disorder in Spectral Domain Optical Coherence Tomography, The journal of Retinal and Vitreous diseases 2011   volume 31. doi: 10.1097/IAE.0b013e3181eef08c