Faculty Bibliography

PURPOSE: To survey the anatomic structures seen in the posterior vitreous using a newly developed technique, dynamic focusing and windowed averaging swept source optical coherence tomography. DESIGN: A cross-sectional study of subjects without a history of eye disease or posterior vitreous detachment. METHODS: A focused illumination beam was swept through the scan depth during 96 successive B-scans and the corresponding most highly resolved portion of each scan was used to make an averaged composite image. The main outcome measures were the frequency and interconnectedness of anatomic features visualized. RESULTS: There were 44 eyes of 25 subjects, who ranged in age from 23 to 62. An optically empty space was seen above the macula in all eyes, and corresponded to the premacular bursa. Above the optic nerve head was a conical space corresponding to the area of Martegiani. The two areas were interconnected in 25 (56.8%) of cases. Anterior to the premacular bursa was another lacuna, that was named the supramacular bursa, which was separate from the premacular bursa in horizontal scans centered on the fovea and found in 38 (86.4%) of eyes. Both the supra- and pre-macular bursae coursed anteriorly and in 21 (55.3%) were seen to interconnect. CONCLUSIONS: The anatomic arrangement of the vitreous is consistent in living eyes with no posterior vitreous detachment, and does not correspond precisely to that described from dissection studies of autopsy specimens. The constancy of the specific findings suggests there may be some beneficial effect from the architectural structure of the vitreous that enhances evolutionary fitness.

Enhanced depth imaging of the optic nerve of a patient with a serous detachment and profound cupping of the optic nerve secondary to angle-closure glaucoma revealed a large dehiscence of the lamina cribrosa. Adjacent to the defect in the lamina were cystoid spaces within the nerve appearing to contain fluid. The most temporal of these could be seen to extend through the optic nerve and up into the macula. This visualized pathway suggests that mechanical dehiscence of the lamina may allow fluid, possibly derived from cerebrospinal fluid, to track up into the macula. [Ophthalmic Surg Lasers Imaging Retina. 2014;45:598-600.].

PURPOSE: To evaluate the concordance between pseudodrusen as manifested by subretinal drusenoid deposits and large choroidal blood vessels using stereological analysis of spectral domain optical coherence tomography (SD-OCT) images. DESIGN: Retrospective, observational, case series. METHODS: The SD-OCT images of 31 consecutive patients with the clinical appearance of pseudodrusen from a private referral retinal clinic were retrospectively reviewed. A grid of 19 evenly spaced vertical lines was randomly superimposed on each SD-OCT image using ImageJ to perform systematic uniform random sampling. The main outcome measure was the likelihood of association between subretinal drusenoid deposits and large choroidal vessels. RESULTS: Uniform random systematic sampling of 589 samples found the proportion of geometric probes intersecting subretinal drusenoid deposits to be 0.28, large choroidal vessel 0.65, and both 0.19. This value was nearly identical to the product of the joint probabilities and was within the 95% confidence interval (0.15-0.21) of the point estimate as calculated by the binomial theorem, indicating mutual independence. The subretinal drusenoid deposits were neither associated with large choroidal vessels nor the intervals in between. CONCLUSIONS: Our results demonstrate that there is no concordance between subretinal drusenoid deposits and large choroidal vessels or the stroma in between. As a consequence, hypotheses postulating that subretinal drusenoid deposits are associated with large choroidal vessels or the choroidal stromal spaces should be abandoned. Stereological techniques are powerful methods used in image evaluation in other fields of study and appear to have utility in analyzing OCT findings of the retina and choroid.

OBJECTIVE: To evaluate the clinical outcomes after vitrectomy with inner retinal fenestration-making a partial thickness retinal hole radial to the pit-for the treatment of optic disc pit maculopathy. DESIGN: Retrospective, interventional case series. PARTICIPANTS: Eighteen eyes with optic disc pit maculopathy. INTERVENTION: Pars plana vitrectomy with creation of an inner retinal fenestration was performed in all eyes. A bent 25-gauge needle was used to make a partial thickness inner retinotomy just temporal to the optic disc pit. MAIN OUTCOME MEASURES: Anatomic outcomes determined by optical coherence tomography and postoperative best-corrected visual acuity (BCVA). RESULTS: Before surgery, gross thickening of the inner and outer retinal layers with accumulation of fluid in the central macula was present in all eyes. Macular detachment was observed in 14 eyes, and outer layer hole was identified in 9 eyes. Patients were followed up for a mean of 34.6+/-26.6 months after surgery. After surgery, complete resolution of fluid in and under the fovea was achieved in 17 eyes (94%) without additional treatment. In these eyes, reduction of the inner retinal fluid was followed by a slow decrease in the outer retinal fluid and macular detachment. The macular detachment resolved in a mean of 6.1+/-3.9 months after surgery. Postoperative BCVA (mean, 0.378+/-0.487 logarithm of the minimum angle of resolution [logMAR]; Snellen equivalent, 20/48) improved significantly compared with preoperative BCVA (mean, 0.725+/-0.510 logMAR; Snellen equivalent, 20/106; P = 0.006). Ten eyes (56%) had a postoperative BCVA of 20/30 or better. There was neither the recurrence of macular detachment nor an accumulation of outer retinal fluid in the central macula in any eyes. CONCLUSIONS: The introduction of a partial thickness fenestration radial to the optic disc pit was associated with retinal anatomic and functional improvement without additional treatments. These results are consistent with the hypothesis that redirection of flow to allow egress of fluid into the vitreous cavity instead of into the retina can achieve long-lasting amelioration of the pathologic findings of optic pit maculopathy.

PURPOSE: To describe the microscopic structure of photoreceptors impacted by subretinal drusenoid deposits, also called pseudodrusen, an extracellular lesion associated with age-related macular degeneration (AMD), using adaptive optics scanning laser ophthalmoscopy (AOSLO). DESIGN: Observational case series. METHODS: Fifty-three patients with AMD and 10 age-similar subjects in normal retinal health were recruited. All subjects underwent color fundus photography, infrared reflectance, red-free reflectance, autofluorescence, and spectral-domain optical coherence tomography (SD-OCT). Subretinal drusenoid deposits were classified with a 3-stage OCT-based grading system. Lesions and surrounding photoreceptors were examined with AOSLO. RESULTS: Subretinal drusenoid deposits were found in 26 eyes of 13 patients with AMD and imaged by AOSLO and SD-OCT in 18 eyes (n=342 lesions). SD-OCT showed subretinal drusenoid deposits as highly reflective material accumulated internal to the retinal pigment epithelium. AOSLO revealed that photoreceptor reflectivity was qualitatively reduced by stage 1 subretinal drusenoid deposits and greatly reduced by stage 2. AOSLO presented a distinct structure in stage 3, a hyporeflective annulus consisting of deflected, degenerated or absent photoreceptors. A central core with a reflectivity superficially resembling photoreceptors is formed by the lesion material itself. A hyporeflective gap in the photoreceptor ellipsoid zone on either side of this core shown in SD-OCT corresponded to the hyporeflective annulus seen by AOSLO. CONCLUSIONS: AOSLO and multimodal imaging of subretinal drusenoid deposits indicate solid, space filling lesions in the subretinal space. Associated retinal reflectivity changes are related to lesion stages and are consistent with perturbations to photoreceptors, as suggested by histology.

PURPOSE: To develop a consensus nomenclature for the classification of retinal and choroidal layers and bands visible on spectral-domain optical coherence tomography (SD-OCT) images of a normal eye. DESIGN: An international panel with expertise in retinal imaging (International Nomenclature for Optical Coherence Tomography [IN*OCT] Panel) was assembled to define a consensus for OCT imaging terminology. PARTICIPANTS: A panel of retina specialists. METHODS: A set of 3 B-scan images from a normal eye was circulated to the panel before the meeting for independent assignment of nomenclature to anatomic landmarks in the vitreous, retina, and choroid. The outputs were scrutinized, tabulated, and used as the starting point for discussions at a roundtable panel meeting. The history of anatomic landmark designations over time was reviewed for the various cellular layers of the ocular structures that are visible by SD-OCT. A process of open discussion and negotiation was undertaken until a unanimous consensus name was adopted for each feature. MAIN OUTCOME MEASURES: Definitions of normal eye features showed by SD-OCT. RESULTS: Definitions for various layers changed frequently in the literature and were often inconsistent with retinal anatomy and histology. The panel introduced the term "zone" for OCT features that seem to localize to a particular anatomic region that lacks definitely proven evidence for a specific reflective structure. Such zones include the myoid, ellipsoid, and the interdigitation zones. CONCLUSIONS: A nomenclature system for normal anatomic landmarks seen on SD-OCT outputs has been proposed and adopted by the IN*OCT Panel. The panel recommends this standardized nomenclature for use in future publications. The proposed harmonizing of terminology serves as a basis for future OCT research studies.

PURPOSE:: To determine the relationship between pseudodrusen as evidenced by the presence of subretinal drusenoid deposits and choroidal thickness using a multimodal imaging approach. METHODS:: Two sets of data were analyzed. The first set was composed of consecutive patients older than 60 years with either high myopia or pseudodrusen. Correlations were calculated between the subfoveal choroidal thickness and the presence of pseudodrusen. The second set of data was obtained from a previously published data examining 90 consecutive eyes with nonexudative age-related macular degeneration so that the relationship between pseudodrusen and subfoveal choroidal thickness could be analyzed. RESULTS:: There were 96 eyes of 53 patients in the first data set, 36 (67.9%) were female and 17 (32.1%) were male. There were 34 patients (61 eyes) in the High Myopia group and 19 patients (35 eyes) in the Primary Pseudodrusen group. The mean age of the Primary Pseudodrusen group was 83.7 years and that of the High Myopia group was 74.9 years, a difference that was significant (P < 0.001). Of the 61 eyes in the High Myopia group, only 3 (4.9%) had pseudodrusen and 0 had conventional drusen. In the Primary Pseudodrusen group, all had pseudodrusen by definition, but 28 (80%) also had conventional drusen. The mean subfoveal choroidal thickness was 181.7 mum (median, 147; interquartile range, 65-225 mum) in the Primary Pseudodrusen group and 59 mum (median, 36; interquartile range, 21-90 mum) in the myopic group. Generalized estimating equation analysis showed that eyes with pseudodrusen had thicker subfoveal choroidal thickness than eyes without, a result driven by the High Myopia group. In the second set of data, while the absolute number of eyes with pseudodrusen had a choroidal thickness between 201 mum and 250 mum, the proportion with pseudodrusen was higher in eyes with thinner choroids, with a broad peak between 50 mum and 100 mum. CONCLUSION:: Our results are not consistent with a simple cause or consequence relationship between pseudodrusen and choroidal thinning, but rather with a third yet unknown factor impacting both the pseudodrusen appearance and the choroidal thinning in susceptible populations. The reasons for the relative lack of drusen and pseudodrusen formation in high myopes need to be ascertained.

PURPOSE:: To describe the prevalence and imaging characteristics of a distinct entity of epiretinal proliferation seen predominantly in association with lamellar macular holes (LMH), termed lamellar hole-associated epiretinal proliferation (LHEP). METHODS:: Retrospective observational case review of 2,030 eyes of 1,104 patients with diagnoses including LMH, full-thickness macular hole, and epiretinal membrane (ERM) imaged with spectral domain optical coherence tomography (SD-OCT) from 2008 to 2013. Lamellar hole-associated epiretinal proliferation, defined on SD-OCT imaging as an epiretinal material of homogenous medium reflectivity, was identified and its features were qualitatively compared against conventional ERM using the SD-OCT data. RESULTS:: Lamellar hole-associated epiretinal proliferation was found in 68 of 2,030 eyes (3.3%), of which 88.2% had LMH and 11.8% had full-thickness macular hole. Lamellar hole-associated epiretinal proliferation was found in 60 of 197 eyes (30.5%) with LMH and 8 of 99 eyes (8.0%) with full-thickness macular hole. Lamellar hole-associated epiretinal proliferation was not seen in 1,734 eyes with ERM, which had no inner retinal defects detectable on SD-OCT. Lamellar hole-associated epiretinal proliferation appeared as a substantial material of homogenous medium reflectivity on the epiretinal surface that demonstrated contiguity with the middle retinal layers and conformed to the adjacent retinal anatomy. Of the eyes with LHEP and LMH, 98% had splitting of the retina in the region of Henle's fiber layer in the area immediately around the partial thickness hole, whereas 88% had visible connecting tissue from the base of the lamellar hole to the proliferating epiretinal tissue. In contrast to ERM, LHEP did not induce tractional effects such as distortion or edema of the underlying normal retinal tissue. Morphologic stability was demonstrated in 97% of eyes containing LHEP in serial eye-tracked SD-OCT images for up to 63 months of retrospective follow-up. CONCLUSION:: Spectral domain optical coherence tomography imaging showed that a subset of patients with LMH had an epiretinal proliferation with medium reflectivity and no evidence of contractile properties that was contiguous with layers of the mid-retina. This phenotype differs from conventionally described ERMs in appearance and induced changes of the underlying retina. Given these distinct anatomical relationships, the presence of LHEP could affect surgical outcomes.