Comparison of time domain stratus oct and spectral domain. Oct, a fundamental tool in the diagnosis and management of patients with choroidal neovascularization cnv, allows identification of active neovascular membranes and determination of the extent of the membranes in many cases. To visualize drusen and larger retinal pigment epithelial detachments, an algorithm was developed for cirrus hdoct carl zeiss meditec, dublin ca to detect. Linefield confocal optical coherence tomography lcoct is an imaging technique based on the principle of timedomain oct with line illumination using a broadband laser and line detection using a line scan camera.
Oct is an interferometric imaging technique that generates cross. Optical coherence tomography has become an invaluable imaging technique for diagnosing and following patients with neovascular agerelated macular degeneration. Optical coherence tomography for agerelated macular. Pseudocysts can be seen on sdoct as a hyporeflective circular shaped lesion. Rapid scan acquisition further increases the diagnostic accuracy of sd oct by eliminating the use of alignment algorithms to correct patient movement in lengthy td scans. The incorporation of the sd oct macular gcc scan may provide additional information in clinical situations that limit the uses of the sd oct rnfl scan by itself, such as in presence of optic disc. Spectraldomain optical coherence tomography imaging of. Automated macular pathology diagnosis in sd oct scans based on multiscale texture and shape features within a pathologyspecific spatial mask abstract purpose. A 43yearold white female presented for a comprehensive eye exam. Spectral domain technology, on the other hand, scans approximately 20,00040,000. Pdf spectral domain optical coherence tomography sd oct. Sd oct horizontal scan over the fovea in a patient with nonexudative amd with geographic atrophy.
Her last mri was performed more than two years ago. Goldberg, md, mba, is a vitreoretinal fellow at tufts new england eye center and ophthalmic consultants of boston. Retinal vascular diseases optical coherence tomography scans. C on the oct map, the upper part of the macular area is atrophic deep blue, asterisk. Oct can detect decreases in retinal thickness and increases in the reflectivity of the. The aim of this study was to use spectral domainoptical coherence tomography sdoct to measure the thickness of the macular inner retinal layer mirl and compare the results between diabetic patients with no signs of retinopathy and healthy subjects. The fovea appears normal because there are no ganglion cell swelling to obscure the fovea. Spectraldomain optical coherence tomography imaging of age. Automated macular pathology diagnosis in sdoct scans.
Optical coherence tomography oct is useful in diagnosing many eye conditions. Projection artifact removal was used when obtaining this image. Optical coherence tomography oct is a noninvasive imaging test that uses light. Spectraldomain sd oct offers improved imaging resolution. Radial vs raster sdoct scan patterns for detection of. With the cirrus hdoct carl zeiss meditec, this is typically a fiveline raster scan.
To report macular thickness values in normal eyes and eyes with diabetic macular edema dme using timedomain td and spectraldomain sd optical coherence. With sdoct scanning in the macula, there is the opportunity to identify the gcl thickness. Sd oct scan from left to right over the area of normal retina and the area involved. A and b, total retinal thickness segmentation software of our own design on macular 3d data sets from the right eye and left eye, respectively. Scan protocols used in the more widely used sdoct systems are mentioned in this section. The standard scan protocol on sdoct machines covers 6 mm. Macular volume determined by optical coherence tomography. Acute branch retinal artery occlusion brao with retinal whitening. Spectral domain optical coherence tomography for glaucoma. Optical coherence tomography oct allows the visualization of the retinal microarchitecture as crosssectional or tomographic volumetric data. Application of optical coherence tomography and macular. This is an eye condition that affects the macula at the back of your eye. Optical coherence tomography in macular hole management preoperative, intraoperative, and postoperative roles. This retrospective analysis of the heidelberg sd octs obtained from patients with various macular pathologies found that the 6line radial oct scan was better for detecting early macular hole formation and focal vitreomacular traction than the 25line raster pattern.
Macular thickness measurement change measured from visittovisit in a patient with diabetic macular edema. Optical coherence tomography oct is a noninvasive, crosssectional and highly reproducible imaging technique that can measure macular thickness 1. The gca algorithm automatically segmented the gcipl and rnfl and calculated the thickness of the macular gcipl and rnfl within a 14. A spectral domain optical coherence tomography line scan of a normal eye. Lcoct produces bscans in realtime from multiple ascans acquired in parallel. A, retinal thickness and volume report that shows the optical coherence tomography oct images, fundus images, thickness and volume charts, and macular thickness maps for each eye of a control participant without disease fast macular thickness map scanning protocol. Optical coherence tomography findings in diabetic macular edema 227 be quite intuitive. Oct its principles, types, interpretation with respect to macular scan. The hyporeflective space does not indicate a cnvm but a degenerative process.
Retinal oct imaging ophthalmic photographers society. The usefulness of oct in the management of various retinal diseases is validated by the possibility to allow early diagnosis and to help in the decisionmaking process. Reproducibility of macular thickness measurements using cirrus. Oct 3d showed an area of depression that was the atrophy. The commercially available spectral domain sd oct offers benefits in glaucoma assessment over the earlier generation of time domainoct due to increased axial resolution, faster scanning speeds and has been reported to have improved reproducibility but similar diagnostic accuracy. The oct exam helps your ophthalmologist see changes to the fibers of the optic nerve. Oct is able capture the thickeningswelling of the inner retinal layers. The scan speed in sweptsource instruments is twice that of sd oct devices 100 000 ascanssec compared with 50 000 ascanssec, enabling faster acquisition of bscans, thus allowing us to obtain widefield bscans 12 mm vs 69 mm with conventional sd oct and more accurate 3d imaging of the vitreous, retina, and choroid figure 2. S5460 november 2012 with 327 reads how we measure reads. Optical coherence tomography oct is a noninvasive diagnostic technique that. The upper limit of the hole is adjacent to the area of retinal atrophy. Optical coherence tomography findings in diabetic macular. Using sd oct, it was found that imaging though gas was easier with a complete gas fill.
The new spectraldomain sd oct devices include a spectrometer in the. Her medical history was significant for multiple sclerosis ms, which was diagnosed five years earlier. Spectral comain optical coherence tomography sd oct images from the patient in figure 14 with possible glaucoma. Ninetyeight glaucomatous eyes and eight normal eyes with macular spectral domain optical coherence tomography sdoct volume scans and. Oct 3d eye scans and age related macular degeneration. Application of optical coherence tomography and macular holes in ophthalmology, optical. Sd oct devices, in contrast, obtain depth information using a spectrometer and advanced mathematics fourier transform, with the mirror remaining stationary. Sd oct scans of geographic atrophy reveals rpe thinning, loss of ez and iz lines, depression of the inner retinal layers as the outer layers are loss, and increase visibility of bruchs membrane and the choroid. This speed has facilitated scanning patterns which can cover up to a 6mm x 6mm area of retina with bscans spaced so tightly that the data can be presented as a three. Brandon lujan, based on his talk at the 2014 american academy of ophthalmology. Because of the difference in medium, oct has a much higher axial resolution than ultrasound, 10.
Measurement of macular structurefunction relationships. For the spectralis heidelberg engineering, it is a 7line scan. Optical coherence tomography in macular hole management. Oct is useful in diagnosing many eye conditions, including. Retinal thickness estimation from sdoct macular scans. Higher axial resolutions can be achieved with higher frequencies of ultrasound. The most commonly used stratus oct macular scan consists of six 6mm. There is loss of outer retinal layers including the rpe, ez, iz. Computerized macular pathology diagnosis in macular sd oct scans. Spectraldomain optical coherence tomography for macular edema. Oct models the cirrus hdocts current software features additional layouts that enable the clinician to see nerve and macular findings on a single printout and formulate functional and structural relationships between visual fields and oct data, respectively.
Temporal macular thinning on spectraldomain optical. The commonly used scan protocols for macular scanning are. Intraoperative sd oct in macular surgery article pdf available in ophthalmic surgery lasers and imaging 436. Clinical advantages of sweptsource oct and new non. Previously, the analysis of postoperative sd oct data in macular hole patients was limited to the manual annotation of defects in a single b scan localized at the foveal center. If i am using sdoct, i order a highresolution raster scan. The injection protocols established in multicenter phase iii studies of ranibizumab for neovascular amd, the anchor and marina trials, consisted of monthly intravitreal. The posterior hyaloid of the vitreous can be identified on macula scans especially with spectraldomain sdoct.
Sd oct can quickly perform serial scans over the macular area. Crosssectional sd oct imaging c and d correlates with the white dashed line in a. In the 20 years since macular hole surgery was first reported by kelly and wendel, our knowledge of and ability to treat macular holes has improved dramatically. Retinalscan analysis can predict advance of macular. Spectral domain optical coherence tomography for glaucoma an. Spectral domain optical coherence tomography sd oct pattern of macular edema and visual acuity in recentonset branch retinal vein occlusion brvo in a tertiary hospital. Retina computerized macular pathology diagnosis in. Rather than simply looking at one 2d b scan, we designed a fully automated analysis algorithm to segment and. The elevated blue and green ridges were due to the scan not finding the rpe and, thus, represented these areas as being elevated. The pronto study prospective optical coherence tomography imaging of patients with neovascular agerelated macular degeneration treated with intraocular ranibizumab.
Currently, all commercially available sdocts offer some form of a specialized macular scan for use in glaucoma evaluation. The vitreous, retinal layers and choroidal layers are visible. Spectral and timedomain optical coherence tomography. In addition, total macular thickness was correlated to visual field mean deviation. How macular oct scanning affects glaucoma evaluation. Optical coherence tomography in agerelated macular. Clinical applications of spectral domain optical coherence. Oct for glaucoma diagnosis, screening and detection of. The movement of this mirror ultimately limits the speed by which tdoct instruments can scan and image the retina. Normative database analysis of rnfl in a healthy top and glaucomatous bottom eye. The first sdoct ophthalmic scans were presented by the same group the following year, where in vivo scans of the iris, lens, macula, and optic disc were all. Another advantage of sdoct is improved retinal coverage by the scan protocols. Computerized 3d spectral domain oct images can help. This scan was acquired with the cirrus sdoct with 5line raster set at 9mm with enhanced depth imaging edi.
The en face scan shows a large, subfoveal branching vascular network. Oct is often used to evaluate disorders of the optic nerve as well. As such, the enhanced performance of sdoct allows for the assessment of macular parameters for glaucoma evaluation because the macula has the highest concentration of rgc in the retina approximately 50% of the rgc of the entire retina. Spectraldomain sd optical coherence tomography oct provides highresolution crosssectional images that have a high correlation with the histologic features of various vitreomacular disorders. On sd oct imaging, a long, elevated section of the rpe can be seen white arrow. Tsechpenakis 1 1 computer and information science department, indiana universitypurdue university indianapolis, usa 2 department of ophthalmology, indiana university school of medicine, usa 3 department of ophthalmology, university of alabama at birmingham school of.
Additionally, by scanning a larger section of the macula, oct enables accurate and consistent evaluation of patients with poor fixation, such as in advanced agerelated macular degeneration. This retinal finding is seen in retinal degenerative conditions and is common in atrophic agerelated macular degeneration. Retinal scan analysis can predict advance of macular degeneration, study finds a new computer algorithm could help physicians predict whether a patients macular degeneration will progress within a years time to the wet stage. However, it should be always remembered that oct technology depicts tissue reflectivity. Sdoct not only can be used to diagnose multiple sclerosis, but also document its progression. To extend an automated method to identify the presence of healthy macula and three macular pathologies macular hole mh, macular edema me, and agerelated. Macular thickness measurement via heidelberg spectralis sd. Macular cube scan cube scans are volume or 3d scans analogous to computed tomography or magnetic resonance scans that acquire volumetric cubes of data. Optical coherence tomography oct is a commonly used imaging modality in the evaluation of glaucomatous damage.
Today at octmd, lets look at an introduction to sd oct spectral domain optical coherence tomography imaging of agerelated macular degeneration amd. Oct image of retinal layers courtesy of heidelberg engineering. The vertical line indicates the orientation of the optical coherence tomography oct scan. These retinal diseases include agerelated macular degeneration amd and. The equipment will then scan your eye without touching it. Glaucoma today measuring macular thickness in glaucoma. Application of optical coherence tomography and macular holes in ophthalmology. Oct 3d eye scans and age related macular degeneration by adelle kirkpatrick what is amd. Spectraldomain optical coherence tomography sdoct highspeed, highresolution imaging of the macula has become an essential tool for evaluating dry and wet agerelated macular degeneration. Spectral domain optical coherence tomography sdoct the oct provides a comfortable and rapid scan that may detect glaucoma, macular degeneration, and diabetic macular edema well before other tests that have been used previously. Macular inner retinal layer thinning in diabetic patients. Sdoct horizontal scan over the fovea in a patient with nonexudative amd with geographic atrophy. These are particularly helpful for visualizing the fine details of macular pathology.
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