Natural History and Surgical Outcomes of Lamellar Macular Holes.

PURPOSE: To assess the natural history and surgical outcomes of lamellar macular holes (LMHs). DESIGN: Retrospective and consecutive case series. SUBJECTS: Patients with LMHs from multiple tertiary care centers. METHODS: Clinical charts and OCT scans were reviewed. MAIN OUTCOME MEASURES: The visual acuity (VA) changes and the occurrence rate of full-thickness macular hole (FTMH) were studied in both groups. Within the operated group, factors associated with 6-month VA and development of FTMH were explored. RESULTS: One hundred seventy-eight eyes were included, of which 89 were monitored and 89 underwent surgery. In the observation group, the mean VA decreased from 0.25 ± 0.18 to 0.28 ± 0.18 logarithm of the minimum angle of resolution (logMAR; P = 0.13), with 14 eyes (15.7%) that lost ≥ 0.2 logMAR VA, after 45.7 ± 33.3 months. Nine eyes (10.1%) spontaneously developed an FTMH. In the operated group, the mean VA increased from 0.47 ± 0.23 to 0.35 ± 0.25 logMAR at 6 months (P < 0.001) and 0.36 ± 0.28 logMAR (P = 0.001) after 24.1 ± 30.1 months. By multivariate analysis, better baseline VA (P < 0.001), the presence of an epiretinal membrane (P = 0.03), and the peeling of the internal limiting membrane (ILM; P = 0.02), with a greater effect of ILM perihole sparing, were associated with a greater 6-month VA. Perihole epiretinal proliferation sparing was associated with a better postoperative VA by univariate analysis (P = 0.03), but this was not significant by multivariate analysis. Eight eyes (9.0%) developed a postoperative FTMH. Using Cox proportional hazard ratios [HRs], pseudophakia at baseline (HR, 0.06; 95% confidence interval [CI], 0.00-0.75; P = 0.03) and peeling of the ILM (HR, 0.05; 95% CI, 0.01-0.39; P = 0.004) were protective factors, while ellipsoid zone disruption (HR, 10.5; 95% CI, 1.04-105; P = 0.05) was associated with an increased risk of FTMH. CONCLUSION: Observed eyes with LMH experienced, on average, progressive VA loss. Patients with LMH and altered vision may benefit from surgery. Internal limiting membrane peeling, with perihole ILM sparing, represents a crucial step of the surgery associated with a greater VA and a lower risk of postoperative FTMH. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

[Vitreous body in the treatment of exudative age-related macular degeneration : The medium is the message]. / Glaskörper bei der Therapie der exsudativen altersabhängigen Makuladegeneration : Das Medium ist die Message.

BACKGROUND: Intravitreal anti-vascular endothelial growth factor (VEGF) is the standard treatment for exudative age-related macular degeneration (AMD). The constitution of the vitreomacular interface varies greatly in cases of attached (with or without traction) or detached vitreous body, which can impact the effectiveness of the anti-VEGF treatment. OBJECTIVE: Based on the current literature this article displays the current state of the science on whether the constitution of the vitreous body has an effect on the anti-VEGF treatment. MATERIAL AND METHODS: The published data extracted from current trials and post hoc analyses concerning this topic are presented and put into the clinical context. RESULTS: The presence of a vitreomacular adhesion reduces the efficacy of anti-VEGF treatment of exudative AMD. Posterior vitreous body detachment represents a positive prognostic factor concerning the efficacy of anti-VEGF treatment but not necessarily the prognosis for visual acuity. CONCLUSION: Patients with attached vitreous body need a more intensive treatment monitoring compared to patients with detached vitreous body. Therefore, in eyes with initial posterior vitreous body detachment receiving a treat and extend regimen, the interval between anti-VEGF injections can be extended to 4 instead of 2 weeks without endangering the success of treatment.

Optical coherence tomography-based consensus definition for lamellar macular hole.

BACKGROUND: A consensus on an optical coherence tomography definition of lamellar macular hole (LMH) and similar conditions is needed. METHODS: The panel reviewed relevant peer-reviewed literature to reach an accord on LMH definition and to differentiate LMH from other similar conditions. RESULTS: The panel reached a consensus on the definition of three clinical entities: LMH, epiretinal membrane (ERM) foveoschisis and macular pseudohole (MPH). LMH definition is based on three mandatory criteria and three optional anatomical features. The three mandatory criteria are the presence of irregular foveal contour, the presence of a foveal cavity with undermined edges and the apparent loss of foveal tissue. Optional anatomical features include the presence of epiretinal proliferation, the presence of a central foveal bump and the disruption of the ellipsoid zone. ERM foveoschisis definition is based on two mandatory criteria: the presence of ERM and the presence of schisis at the level of Henle's fibre layer. Three optional anatomical features can also be present: the presence of microcystoid spaces in the inner nuclear layer (INL), an increase of retinal thickness and the presence of retinal wrinkling. MPH definition is based on three mandatory criteria and two optional anatomical features. Mandatory criteria include the presence of a foveal sparing ERM, the presence of a steepened foveal profile and an increased central retinal thickness. Optional anatomical features are the presence of microcystoid spaces in the INL and a normal retinal thickness. CONCLUSIONS: The use of the proposed definitions may provide uniform language for clinicians and future research.

Macular Microcysts in Mitochondrial Optic Neuropathies: Prevalence and Retinal Layer Thickness Measurements.

PURPOSE: To investigate the thickness of the retinal layers and to assess the prevalence of macular microcysts (MM) in the inner nuclear layer (INL) of patients with mitochondrial optic neuropathies (MON). METHODS: All patients with molecularly confirmed MON, i.e. Leber's Hereditary Optic Neuropathy (LHON) and Dominant Optic Atrophy (DOA), referred between 2010 and 2012 were enrolled. Eight patients with MM were compared with two control groups: MON patients without MM matched by age, peripapillary retinal nerve fiber layer (RNFL) thickness, and visual acuity, as well as age-matched controls. Retinal segmentation was performed using specific Optical coherence tomography (OCT) software (Carl Zeiss Meditec). Macular segmentation thickness values of the three groups were compared by one-way analysis of variance with Bonferroni post hoc corrections. RESULTS: MM were identified in 5/90 (5.6%) patients with LHON and 3/58 (5.2%) with DOA. The INL was thicker in patients with MON compared to controls regardless of the presence of MM [133.1±7µm vs 122.3±9µm in MM patients (p<0.01) and 128.5±8µm vs. 122.3±9µm in no-MM patients (p<0.05)], however the outer nuclear layer (ONL) was thicker in patients with MM (101.4±1mµ) compared to patients without MM [77.5±8mµ (p<0.001)] and controls [78.4±7mµ (p<0.001)]. ONL thickness did not significantly differ between patients without MM and controls. CONCLUSION: The prevalence of MM in MON is low (5-6%), but associated with ONL thickening. We speculate that in MON patients with MM, vitreo-retinal traction contributes to the thickening of ONL as well as to the production of cystic spaces.

Inner retinal optic neuropathy: vitreomacular surgery-associated disruption of the inner retina.

PURPOSE: Macular pucker (MP) and macular hole (MH) are vitreomaculopathies treated by vitrectomy and membrane peel. The complication of postoperative central scotoma can be associated with significant reduction in visual acuity (VA). We seek to determine whether retinal nerve fiber layer (RNFL) disruption is the pathophysiologic basis of this defect. Mitigating clinical circumstances also were sought. METHODS: Eleven eyes from 10 pseudophakic patients who had undergone vitrectomy with peeling for either MH or MP were studied with clinical measures, including optical coherence tomography (OCT). Membrane specimens were evaluated by immunohistochemistry for neurofilament, a marker for the inner retina. Ten eyes from 10 pseudophakic patients who underwent repeat surgery for persistent or recurrent pathology were evaluated to determine the relationship between the timing of reoperation and clinical outcome. RESULTS: Cases with a postoperative central scotoma (N=4) had worse VA (~20/600) compared to those without (N=7, ~20/30, P=0.01). Eyes with a central scotoma had significantly reduced RNFL thickness in the temporal quadrant (53.67 vs. 72.33 µm, P=0.05) by OCT. A central scotoma was associated with more disruption of the inner retina on immunohistochemistry (P=0.03). In patients with persistent or recurrent pathology, waiting six months before reoperation resulted in better functional outcomes (P=0.03). CONCLUSIONS: Central scotomata and poor VA were associated with disruption of the RNFL during membrane peeling. Affected patients have RNFL thinning and signs of optic neuropathy, for which we propose the term inner retinal optic neuropathy (IRON). In patients requiring reoperation, waiting six months between surgeries may reduce the risk of IRON.

Vitrectomy for floaters: prospective efficacy analyses and retrospective safety profile.

PURPOSE: Floaters impact vision but the mechanism is unknown. We hypothesize that floaters reduce contrast sensitivity function, which can be normalized by vitrectomy, and that minimally invasive vitrectomy will have lower incidences of retinal tears (reported at 30%) and cataracts (50-76%). METHODS: Seventy-six eyes (34 phakic) with floaters were evaluated in 2 separate studies. Floater etiologies were primarily posterior vitreous detachment in 61 of 76 eyes (80%) and myopic vitreopathy in 24 of 76 eyes (32%). Minimally invasive 25G vitrectomy was performed without posterior vitreous detachment induction, leaving anterior vitreous, and using nonhollow probes for cannula extraction. Efficacy was studied prospectively (up to 9 months) in 16 floater cases with Freiburg Acuity Contrast Testing (Weber index [%W] reproducibility = 92.1%) and the National Eye Institute Visual Function Questionnaire. Safety was separately evaluated in 60 other cases followed up on an average of 17.5 months (range, 3-51 months). RESULTS: Floater eyes had 67% contrast sensitivity function attenuation (4.0 ± 2.3 %W; control subjects = 2.4 ± 0.9 %W, P < 0.013). After vitrectomy, contrast sensitivity function normalized in each case at 1 week (2.0 ± 1.4 %W, P < 0.01) and remained normal at 1 month (2.0 ± 1.0 %W, P < 0.003) and 3 months to 9 months (2.2 ± 1.5 %W, P < 0.018). Visual Function Questionnaire was 28.3% lower in floater patients (73.2 ± 15.6, N = 16) than in age-matched control subjects (93.9 ± 8.0, N = 12, P < 0.001), and postoperatively improved by 29.2% (P < 0.001). In the safety study of 60 floater cases treated with vitrectomy, none developed retinal breaks, infection, or glaucoma after a mean follow-up of 17.5 months. Only 8 of 34 cases (23.5%) required cataract surgery (none younger than 53 years) at an average of 15 months postvitrectomy. CONCLUSION: Floaters lower contrast sensitivity function, which normalizes after vitrectomy. Visual Function Questionnaire quantified improvement in satisfaction. Not inducing posterior vitreous detachment reduced retinal tear incidence from 30% to 0% (P < 0.007). Postvitrectomy cataract incidence was reduced from 50% to 23.5% (P < 0.02). This approach thus seems effective and safe in alleviating the visual dysfunction induced by floaters.

The International Vitreomacular Traction Study Group classification of vitreomacular adhesion, traction, and macular hole.

OBJECTIVE: The International Vitreomacular Traction Study (IVTS) Group was convened to develop an optical coherence tomography (OCT)-based anatomic classification system for diseases of the vitreomacular interface (VMI). DESIGN: The IVTS applied their clinical experience, after reviewing the relevant literature, to support the development of a strictly anatomic OCT-based classification system. PARTICIPANTS: A panel of vitreoretinal disease experts was the foundation of the International Classification System. METHODS: Before the meeting, panel participants were asked to review 11 articles and to complete 3 questionnaires. The articles were preselected based on searches for comprehensive reviews covering diseases of the VMI. Responses to questionnaires and the group's opinions on definitions specified in the literature were used to guide the discussion. MAIN OUTCOME MEASURES: Optical coherence tomography-based anatomic definitions and classification of vitreomacular adhesion, vitreomacular traction (VMT), and macular hole. RESULTS: Vitreomacular adhesion is defined as perifoveal vitreous separation with remaining vitreomacular attachment and unperturbed foveal morphologic features. It is an OCT finding that is almost always the result of normal vitreous aging, which may lead to pathologic conditions. Vitreomacular traction is characterized by anomalous posterior vitreous detachment accompanied by anatomic distortion of the fovea, which may include pseudocysts, macular schisis, cystoid macular edema, and subretinal fluid. Vitreomacular traction can be subclassified by the diameter of vitreous attachment to the macular surface as measured by OCT, with attachment of 1500 µm or less defined as focal and attachment of more than 1500 µm as broad. When associated with other macular disease, VMT is classified as concurrent. Full-thickness macular hole (FTMH) is defined as a foveal lesion with interruption of all retinal layers from the internal limiting membrane to the retinal pigment epithelium. Full-thickness macular hole is primary if caused by vitreous traction or secondary if directly the result of pathologic characteristics other than VMT. Full-thickness macular hole is subclassified by size of the hole as determined by OCT and the presence or absence of VMT. CONCLUSIONS: This classification system will support systematic diagnosis and management by creating a clinically applicable system that is predictive of therapeutic outcomes and is useful for the execution and analysis of clinical studies.

Prospective three-dimensional analysis of structure and function in vitreomacular adhesion cured by pharmacologic vitreolysis.

PURPOSE: To prospectively characterize macular structure and function as assessed by combined three-dimensional spectral-domain optical coherence tomography and scanning laser ophthalmoscopy and 3D computer-automated threshold Amsler grid, respectively, in a patient undergoing pharmacologic vitreolysis for vitreomacular adhesion with tractional cysts. METHODS: Combined 3D optical coherence tomography and scanning laser ophthalmoscopy measured macular volume and 3D computer-automated threshold Amsler grid quantified central visual field function by determining the absolute percent magnitude lost (cumulative value of total visual field loss over all tested levels) before and for a period of 6 months after pharmacologic vitreolysis for vitreomacular adhesion with a single intravitreal injection of microplasmin (125 µg; ThromboGenics). RESULTS: Ocriplasmin pharmacologic vitreolysis released vitreomacular adhesion by 2 weeks and decreased macular volume from 0.32 µL to 0.15 µL by 1 year after injection. There was a concomitant 4-fold improvement in visual function as measured by 3D computer-automated threshold Amsler grid (percent of central visual field lost) and Snellen visual acuity improved from 20/200 to 20/40. CONCLUSION: For assessing macular function improvement in conjunction with structural reintegration after pharmacologic vitreolysis for vitreomacular adhesion, 3D computer-automated threshold Amsler grid is a useful tool. Both 3D measurements quantitatively characterized the resolution of this patient's vitreomacular adhesion, suggesting that this is a useful approach to quantifying macular structure and function as indices of the severity of disease and the response to therapy.

Neuron-specific enolase is elevated in asymptomatic carriers of Leber's hereditary optic neuropathy.

PURPOSE: Neuron-specific enolase (NSE) is a biomarker for neuronal stress. Leber's hereditary optic neuropathy (LHON) is a mitochondrial disease affecting retinal ganglion cells (RGC). These RGCs and their axons in the retinal nerve fiber layer (RNFL) and optic nerve head may show subclinical pathology in unaffected mutation carriers, or undergo cell death in affected patients. We hypothesize that increased levels of blood NSE may characterize LHON carriers as a biomarker of ongoing RGC stress. METHODS: Serum was obtained from 74 members of a Brazilian pedigree with LHON carrying the homoplasmic 11778/ND4 mitochondrial DNA mutation. Classified by symptoms and psychophysical metrics, 46/74 patients were unaffected mutation "carriers," 14/74 were "affected," and 14/74 were "off-pedigree" controls. Serum NSE levels were determined by ELISA specific for the γ subunit of NSE. RESULTS: Serum NSE concentrations in carriers (27.17 ± 39.82 µg/L) were significantly higher than affected (5.66 ± 4.19 µg/L; P = 0.050) and off-pedigree controls (6.20 ± 2.35 µg/L; P = 0.047). Of the 14/46 (30.4 %) carriers with significantly elevated NSE levels (mean = 75.8 ± 42.3 µg/L), 9/14 (64.3%) were male. Furthermore, NSE levels were nearly three times greater in asymptomatic male carriers (40.65 ± 51.21 µg/L) than in asymptomatic female carriers (15.85 ± 22.27 µg/L; P = 0.034). CONCLUSIONS: Serum NSE levels are higher in LHON carriers compared with affected and off-pedigree individuals. A subgroup of mostly male carriers had significantly elevated serum NSE levels. Thus, male carriers are at higher risk for LHON-related neuronal stress.

Novel vitreous modulators for pharmacologic vitreolysis in the treatment of diabetic retinopathy.

Vitreous constitutes about 80% of the volume of the human eye. It is an extended extracellular matrix that is composed of collagen, hyaluronan, and other extracellular matrix molecules, but mostly water. In both health as well as disease, especially diabetic retinopathy (DR), special attention should be drawn to the posterior vitreous cortex and its relation to the retinal surface. The important role of vitreous in the pathogenesis of proliferative DR has already been demonstrated by several experimental and clinical studies. Thus, vitreo-retinal separation by pharmacologic vitreolysis and/or removal by surgical means are appropriate approaches to interrupt the pathogenic contribution of vitreous and prevent progression of diabetic retinopathy to more advanced stages. This review describes various aspects of the molecular morphology and structural anatomy of vitreous and the vitreo-retinal interface, as well as the role of vitreous in the pathophysiology of DR. Lastly, this treatise provides a critical analysis of novel vitreous modulators for pharmacologic vitreolysis in the treatment of DR. Microplasmin is currently the most promising approach to treat vitreoretinal traction by pharmacologic vitreolysis.

Vitreo-papillary adhesion in macular hole and macular pucker.

PURPOSE: Vitreo-macular pathology may be influenced by vitreo-papillary adhesion (VPA). Optical coherence tomography/scanning laser ophthalmoscopy (OCT/SLO) was used to identify VPA in full-thickness macular hole, lamellar hole, and macular pucker (MP). METHODS: Ultrasonography and OCT/SLO were performed in 55 subjects: 16 with macular hole, 11 with lamellar hole, and 28 with MP. The main outcome measures were the presence of posterior vitreous detachment by ultrasound, and the findings of VPA and intraretinal cysts by OCT/SLO. RESULTS: Posterior vitreous detachment was detected by ultrasound in 26/28 (92.9%) eyes with MP, 6/11 (54.5%) eyes with lamellar hole (P < 0.05), and 4/16 (25%) eyes with macular hole (P < 0.00001). Optical coherence tomography/scanning laser ophthalmoscopy detected VPA in 14/16 (87.5%) macular hole eyes, 4/11 (36.4%) lamellar hole eyes (P < 0.05), and 5/28 (17.9%) MP eyes (P < 0.00005). Intraretinal cysts were present in 4/5 (80%) MP eyes with VPA but only 1/23 (4.3%) MP eyes without VPA (P < 0.005). CONCLUSION: Vitreo-papillary adhesion was significantly more common in full-thickness macular hole than lamellar hole or MP. When present in MP, VPA was frequently associated with intraretinal cysts. Hence, VPA may have an important influence on the vectors of force at the vitreo-retinal interface inducing holes and cysts.

Vitreomacular adhesion in active and end-stage age-related macular degeneration.

PURPOSE: To evaluate vitreomacular relations in different stages of age-related macular degeneration (AMD) without the influence of genetics and environmental factors. DESIGN: Retrospective, observational case series. METHODS: This was a multicenter study consisting of 29 previously untreated subjects with active exudative (wet) AMD in one eye and active nonexudative (dry) AMD in the fellow eye who were compared with 10 previously untreated subjects with end-stage geographic atrophy in one eye and an end-stage fibrotic (disciform) scar in the fellow eye. All subjects were studied with ultrasonography to identify the presence of posterior vitreous detachment (PVD) and by optical coherence tomography to detect vitreomacular adhesion (VMA). RESULTS: The incidence of PVD in eyes with nonexudative AMD was 20 (69%) of 29, compared with 6 (21%) of 29 with active exudative AMD (P = .002). VMA was present in 11 (38%) of 29 of eyes with exudative AMD and in only 3 (10%) of 29 eyes with nonexudative AMD (P = .008). The incidence of PVD in geographic atrophy was 7 (70%) of 10, compared with 4 (40%) of 10 with disciform scar (P = .44). VMA was present in 2 (20%) of 10 eyes with disciform scars and in 0 (0%) of 10 eyes with geographic atrophy (P = .48). CONCLUSIONS: PVD may protect against exudative AMD, whereas VMA may promote exudative AMD. This phenomenon is not evident in end-stage disease because of an increased incidence of PVD and a decreased incidence of VMA in eyes with disciform scars. Genetic and environmental factors do not seem to influence these observations.

Posterior vitreomacular adhesion: a potential risk factor for exudative age-related macular degeneration?

PURPOSE: To compare the state of the posterior vitreous in exudative age-related macular degeneration (AMD) with eyes with nonexudative AMD and controls. DESIGN: Prospective, observational case series. METHODS: B-scan ultrasonography and optical coherence tomography (OCT) were performed in 163 eyes from 82 subjects older than 55 years, 50 eyes with exudative AMD, 57 with nonexudative AMD, and 56 control eyes. Main outcome measures were the number of eyes with complete posterior vitreous detachment (PVD) by ultrasound and the number of eyes with central vitreomacular adhesion by OCT. RESULTS: By ultrasonography, 17 (34.0%) of 50 eyes with exudative AMD had PVD as compared with 41 (71.9%) of 57 eyes with nonexudative AMD (P = .00002) and 34 (60.7%) of 56 controls (P = .017). OCT detected persistent central vitreoretinal adhesion surrounded by a detached posterior vitreous cortex in 18 (36%) of 50 eyes with exudative AMD, significantly higher than in nonexudative AMD (4/57 [7%]; P < .0001) and in controls (6/56 [10%]; P = .002). CONCLUSIONS: Persistent attachment of the posterior vitreous cortex to the macula may be another risk factor for the development of exudative AMD via vitreoretinal traction inducing chronic low-grade inflammation, by maintaining macular exposure to cytokines or free radicals in the vitreous gel, or by interfering in transvitreous oxygenation and nutrition of the macula. Inducing PVD may provide prophylactic benefit against exudative AMD.

Macular holes and macular pucker: the role of vitreoschisis as imaged by optical coherence tomography/scanning laser ophthalmoscopy.

PURPOSE: The pathogenesis of macular pucker and macular holes is poorly understood. Anomalous posterior vitreous detachment (PVD) and vitreoschisis have been proposed as possible mechanisms. This study used clinical imaging to seek vitreoschisis and study the topographic features of macular pucker and macular holes. METHODS: Combined optical coherence tomography and scanning laser ophthalmoscopy (OCT/SLO) was performed in 45 eyes with macular hole and 44 eyes with macular pucker. Longitudinal imaging was used to identify vitreoschisis and measure retinal thickness. The topographic features of eyes with macular hole with eccentric macular contraction were compared to 24 eyes with unifocal macular pucker using coronal plane imaging. RESULTS: Vitreoschisis was detected in 24 of 45 eyes (53.3%) with macular hole and 19 of 44 (43.2%) with macular pucker. Retinal contraction was detected eccentrically in the macula of 18 of 45 eyes (40%) with macular hole. In eyes with macular hole with unifocal retinal contraction, the average surface area of contraction (23.12 +/- 18.79 mm(2)) was significantly smaller than in eyes with macular pucker (63.20 +/- 23.68 mm(2); P = .006). The distance from the center of retinal contraction to the center of the macula was significantly greater in eyes with macular hole (8.64 +/- 2.33 mm) than eyes with macular pucker (4.45 +/- 1.90 mm; P = .0001). CONCLUSION: Vitreoschisis was detected in about half of all eyes with macular hole and macular pucker. The topographic and structural features in eyes with macular hole with retinal contraction differed in comparison to eyes with macular pucker alone, suggesting that although each condition may begin with anomalous PVD, differences in subsequent cell migration and proliferation probably result in the different clinical appearances detected in this study.

Perioperative risk factors for posterior ischemic optic neuropathy.

BACKGROUND: Infarction of the optic nerve posterior to the lamina cribrosa, called posterior ischemic optic neuropathy (PION), is a condition that can result in profound bilateral blindness. Cases of PION treated at this institution and those described in the literature were analyzed to identify clinical features that profile those individuals at risk of PION in an attempt to identify major contributing factors that could be addressed prophylactically to enable effective prevention. STUDY DESIGN: Salient clinical features in seven cases of PION diagnosed at the Doheny Eye Institute between 1989 and 1998 are compared with 46 cases of PION reported in the literature. RESULTS: In the Doheny series there were six men and one woman aged 12 to 66 years (mean, 47 years). Five patients were status-post spine surgery, one was status-post knee surgery, and one had a bleeding stomach ulcer. Vision loss was simultaneously bilateral in six of seven patients (85.7%) and was apparent immediately after surgery. There were no abnormal retinal or choroidal findings including diabetic retinopathy, in any of the patients. Notable contributing factors were blood loss in all seven patients, ranging from 2,000 to 16,000 mL, with a drop in hematocrit of 9.5% to 19% (mean, 14%), and intraoperative systemic hypotension in all patients. Facial edema was a factor in three of six spine surgery patients (50%). Patients reported in the literature had a mean age of 50 years and were also predominantly men (34 of 46, 74%) who underwent spine surgery (30 of 46, 65.2%). CONCLUSIONS: Middle-aged men undergoing spine surgery with prolonged intraoperative hypotension and postoperative anemia and facial swelling are at risk of developing PION from hypovolemic hypotension. Avoiding or immediately correcting these contributory factors can reduce the incidence of PION.