Optical Coherence Tomography of Peripheral Retina and Vitreoretinal Interface



Fig. 2.1
OCT of the retina in emmetropic patient. Scan 1 Macular area. The average foveal and parafoveal retinal thickness is 222 μm and 355 μm, respectively. Scan 2 Equatorial area. The average retinal thickness is 171 μm. Scan 3 Mid-peripheral area. The average retinal thickness is 155 μm. Scan 4 Far peripheral area. The average retinal thickness is 132 μm





Scan 2 Equatorial area

The retinal surface is smooth. Hyperreflective layers of the pigment epithelium, photoreceptors, and neuroepithelium are observed. Retinal vessels are observed as shadows. The posterior hyaloid membrane is adherent. Large choroidal vessels are identified. The average retinal thickness is 171 μm.


Scan 3 Mid-peripheral area

The retinal surface is smooth. The inner and outer layers of the neuroepithelium are poorly distinguished. Retinal vessels are observed as shadows. The posterior hyaloid membrane is intact. Medium-sized choroidal vessels are identified. The average retinal thickness is 155 μm.


Scan 4 Far peripheral area

The retinal surface is smooth. The inner and outer layers of the neuroepithelium are poorly distinguished. Retinal vessels and small choroidal vessels are identified. The average retinal thickness is 132 μm.



Conclusion


The retinal layers are more clearly distinguished in the central retina and equatorial area. The retinal thickness gradually decreases from the center to the periphery. The equatorial area is 2 times thinner, the mid-peripheral area is 2.3 times thinner, and the far-peripheral area is 2.7 times thinner than the parafoveal area.



Moderate Hyperopia


A 37-year-old male complaining of deterioration of distance and near vision.

OD: VA, sc 20/200, cc 20/20 with +4.5 sph; AL, 21.9 mm.


OCT Scan Description (Fig. 2.2)



Scan 1 Macular area

The foveal pit retains a normal profile. All retinal layers are clearly distinguished. The pigment epithelium is smooth. Retinal vessels are observed as shadows parafoveally and perifoveally. The average foveal and parafoveal retinal thickness is 245 μm and 375 μm, respectively.

A420797_2_En_2_Fig2_HTML.gif


Fig. 2.2
OCT of the retina in hyperopic patient. Scan 1 Macular area. The average foveal and parafoveal retinal thickness is 245 μm and 375 μm, respectively. Scan 2 Equatorial area. The average retinal thickness is 193 μm. Scan 3 Mid-peripheral area. The average retinal thickness is 174 μm. Scan 4 Far peripheral area. The average retinal thickness is 151 μm


Scan 2 Equatorial area

The retinal surface is smooth. Hyperreflective layers of the pigment epithelium, photoreceptors, and neuroepithelium are observed. Retinal vessels are observed as shadows. Large and medium-sized choroidal vessels are identified. The average retinal thickness is 193 μm.


Scan 3 Mid-peripheral area

The retinal surface is smooth. The inner and outer layers of the neuroepithelium are distinguishable. Retinal vessels are observed as shadows. Medium-sized choroidal vessels are identified. The average retinal thickness is 174 μm.


Scan 4 Far peripheral area

The retinal surface is smooth. The inner and outer layers of the neuroepithelium are distinguishable. Retinal vessels and small choroidal vessels are identified. The average retinal thickness is 151 μm.


Conclusion


Retinal OCT in moderate hyperopia demonstrates decreasing retinal thickness from the center to the periphery. The equatorial area is 1.9 times thinner, the mid-peripheral area is 2.2 times thinner, and the far peripheral area is 2.5 times thinner than the central retina. Retinal thickness in patients with moderate hyperopia is 9 % higher in the foveal area, 5.4 % higher in the parafoveal area, 11.4 % higher in the equatorial area, 10.9 % higher in the mid-peripheral area, and 12.6 % higher in the far peripheral area than that in patients with emmetropia.


Moderate Myopia


An asymptomatic 36-year-old female complaining of low distance vision.

OD: VA, sc 20/200, cc 20/20 with −5.5 sph; AL, 25.8 mm.


OCT Scan Description (Fig. 2.3)



Scan 1 Macular area

The foveal pit retains a normal profile. All retinal layers are clearly distinguished. Pigment epithelium is smooth. Retinal vessels are observed as shadows parafoveally and perifoveally. The average foveal and parafoveal retinal thickness is 208 μm and 302 μm, respectively.

A420797_2_En_2_Fig3_HTML.gif


Fig. 2.3
OCT of the retina in myopic patient. Scan 1 Macular area. The average foveal and parafoveal retinal thickness in is 208 μm and 302 μm, respectively. Scan 2 Equatorial area. The average retinal thickness is 161 μm. Scan 3 Mid-peripheral area. The average retinal thickness is 145 μm. Scan 4 Far peripheral area. The average retinal thickness is 126 μm


Scan 2 Equatorial area

The retinal surface is smooth. Hyperreflective layers of the pigment epithelium, photoreceptors, and neuroepithelium are observed. Retinal vessels are observed as shadows. The posterior hyaloid membrane is intact. Large choroidal vessels are identified. The average retinal thickness is 161 μm.


Scan 3 Mid-peripheral area

The retinal surface is smooth. The inner and outer layers of the neuroepithelium are distinguishable. Retinal vessels are observed as shadows. The posterior hyaloid membrane is intact. Medium-sized choroidal vessels are identified. The average retinal thickness is 145 μm.


Scan 4 Far peripheral area

The retinal surface is smooth. The inner and outer layers of the neuroepithelium are not distinguishable. Retinal vessels and small choroidal vessels are identified. The average retinal thickness is 126 μm.


Conclusion


Retinal OCT in moderate myopia demonstrates decreasing retinal thickness from the parafoveal area to the periphery. The equatorial area is 1.9 times thinner, the mid-peripheral area is 2.1 times thinner, and the far peripheral area is 2.4 times thinner than the central retina. The average retinal thickness in patients with moderate myopia is 6.3 % lower in the fovea, 14.9 % lower in the parafovea, 5.9 % lower in the equatorial area, 6.5 % lower in the mid-peripheral area, and 4.5 % lower in the far peripheral retina than that in patients with emmetropia.


Jun 27, 2017 | Posted by in OPHTHALMOLOGY | Comments Off on Optical Coherence Tomography of Peripheral Retina and Vitreoretinal Interface
Premium Wordpress Themes by UFO Themes