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Dive into the research topics where Dennis A. Orlock is active.

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Featured researches published by Dennis A. Orlock.


Retina-the Journal of Retinal and Vitreous Diseases | 2012

Digital indocyanine green videoangiography and choroidal neovascularization.

Lawrence A. Yannuzzi; Jason S. Slakter; John A. Sorenson; David R. Guyer; Dennis A. Orlock

This report describes a new system for digital indocyanine green videoangiography (ICGV) that provides enhanced imaging of the choroidal circulation. This newly assembled system was used to study a consecutive series of 129 patients with exudative age-related macular degeneration (AMD), and ill-defined or occult choroidal neovascularization (CNV). Overall, 39% of the patients in this study with occult CNV could be reclassified as having well-delineated or so-called classic CNV by virtue of the additional findings provided by ICGV. In this series, ICGV was particularly useful in identifying occult CNV in eyes with a large, serous pigment epithelial detachment (PED) and in eyes with recurrent CNV after previous laser photocoagulation treatment. Some of these patients were selected for laser photocoagulation of the abnormal choroidal vessels in order to evaluate the feasibility of this form of treatment on the basis of combined clinical, fluorescein angiographic, and ICGV findings. The results of this study suggest that ICGV is an important adjunct in the evaluation, classification, and laser treatment of patients with occult CNV secondary to AMD.


Retina-the Journal of Retinal and Vitreous Diseases | 1996

Indocyanine green videoangiography of older patients with central serous chorioretinopathy.

Richard F. Spaide; Lisa Hall; Anton Haas; Laura Campeas; Lawrence A. Yannuzzi; Yale L. Fisher; David R. Guyer; Jason S. Slakter; John A. Sorenson; Dennis A. Orlock

Purpose: The authors studied the indocyanine green (ICG) videoangiography findings of central serous chorioretinopathy (CSC) in older adults. Background: Central serous chorioretinopathy in older adults may be confused with the exudative forms of age-related macular degeneration (AMD) because the two entities may have similar ophthalmoscopic and fluorescein angiographic findings. Because of its enhanced ability to image the choroidal circulation, ICG videoangiography has been used to describe certain choroidal vascular abnormalities in young adults with CSC, as well as older patients with choroidal neovascularization (CNV). The ICG videoangiography findings in CSC in older adults is largely unknown. Methods: The authors performed ICG videoangiography on 36 patients aged 50 years or older with CSC to characterize their findings. Results: The ICG videoangiography findings of the patients were consistent, revealing choroidal vascular hyperpermeability manifested by areas of hyperfluorescence that were first seen in the midphase of the angiogram. In the later phases of the angiogram, there were dispersion of the hyperfluorescence and a distinctive silhouetting of the larger choroidal vessels. Conclusions: Older patients with CSC have a unique temporal and topographic pattern of hyperpermeability that can help establish the proper diagnosis.


Ophthalmology | 1996

Central Serous Chorioretinopathy in Younger and Older Adults

Richard F. Spaide; Laura Campeas; Anton Haas; Laaurence A. Yannuzzi; Yale L. Fisher; David R. Guyer; Jason S. Slakter; John A. Sorenson; Dennis A. Orlock

PURPOSE The purpose of the study is to investigate the demographic characteristics and clinical findings of central serous chorioretinopathy (CSC). METHODS This study examined a consecutive series of 130 patients with CSC seen over an 18-month period. RESULTS The mean age of the patients when examined was 51 years, and the male-to-female ratio was 2.6:1.0. A total of 62 patients were older than 50 years of age when first examined. Although the patients shared some clinical and angiographic similarities, the older patients had a lower mean visual acuity and were more likely to have diffuse retinal pigment epitheliopathy, bilateral involvement, and secondary choroidal neovascularization than were the younger patients. With ophthalmoscopic and angiographic examination results, it was possible to differentiate CSC in older adults from choroidal neovascularization. CONCLUSION This study expands the clinical concept of CSC. The male-to-female ratio was much lower, and the range of ages of the patients was much greater than in previous studies. Disease manifestations in older adults differed somewhat from those seen in younger adults. In older patients, CSC can be distinguished from other exudative maculopathies, particularly that of choroidal neovascularization secondary to age-related macular degeneration.


Ophthalmology | 2000

Retinal choroidal anastomoses and occult choroidal neovascularization in age-related macular degeneration.

Jason S. Slakter; Lawrence A. Yannuzzi; Ulrike Schneider; John A. Sorenson; Antonio P. Ciardella; David R. Guyer; Richard F. Spaide; K. Bailey Freund; Dennis A. Orlock

OBJECTIVE This study was designed to identify the incidence of retinal choroidal anastomoses in patients with occult choroidal neovascularization (CNV) and focal hot spots on indocyanine green (ICG) angiography, to identify the clinical and angiographic features that would assist in their identification, and to determine if the presence of these anastomotic lesions affect the outcome of laser therapy. DESIGN Combined prospective and retrospective cross-sectional study. PARTICIPANTS One hundred fifty consecutive patients with newly diagnosed occult CNV secondary to exudative age-related macular degeneration and focal hot spots on ICG angiography were evaluated prospectively. In addition, a retrospective review was performed on 79 eyes previously reported to have undergone laser photocoagulation treatment with ICG guidance. METHODS AND TESTING: In all cases, stereo color and red-free photographs, and stereo fluorescein and digital ICG angiograms were obtained for evaluation. MAIN OUTCOME MEASURES Images obtained by all four techniques were evaluated for the presence of a retinal choroidal anastomosis. Associated clinical and angiographic findings were noted. In the retrospective review, the success rate of laser treatment was correlated with the presence or absence of a retinal choroidal anastomosis. RESULTS Of the 150 eyes evaluated prospectively, 31 (21%) were found to have a retinal choroidal anastomosis. Retinal choroidal anastomoses were found in 27% of patients with associated serous pigment epithelial detachment (PED), whereas 13% were found in those without an associated elevation of the retinal pigment epithelium. Seventy-one percent of eyes had multiple anastomotic connections. Ninety percent of eyes had at least one retinal vein involved in the anastomotic connection. Clinical evidence of preretinal and intraretinal hemorrhage and cystic edema coupled with angiographic evidence of intraretinal dye leakage were key features of retinal choroidal anastomoses. In the retrospective review, seven patients were found to have retinal choroidal anastomoses with associated serous PED and demonstrated a very low (14%) success rate for laser treatment. CONCLUSIONS Retinal choroidal anastomoses can present as a primary manifestation of the exudative process in age-related macular degeneration. They may be seen in eyes with and without detachment of the retinal pigment epithelium. Specific clinical and angiographic features have been identified that can aid in the diagnosis of these vascular anomalies. Their presence represents a poor prognostic sign for successful ICG-guided laser treatment.


Ophthalmology | 2000

Polypoidal choroidal vasculopathy masquerading as central serous chorioretinopathy

Lawrence A. Yannuzzi; K. Bailey Freund; Mauro Goldbaum; Baldo Scassellati-Sforzolini; David R. Guyer; Richard F. Spaide; David Maberley; Doric W. K. Wong; Jason S. Slakter; John A. Sorenson; Yale L. Fisher; Dennis A. Orlock

OBJECTIVE To differentiate polypoidal choroidal vasculopathy (PCV) from central serous chorioretinopathy (CSC). DESIGN A retrospective, observational case series. PARTICIPANTS Thirteen patients originally diagnosed with CSC proved to have PCV after more extensive evaluation and follow-up. METHODS A clinical and angiographic review of patients with manifestations of CSC, including macular detachment. MAIN OUTCOME MEASURES Demographic data, funduscopic examination, and fluorescein and indocyanine green (ICG) angiographic findings. RESULTS Thirteen patients initially suspected of having CSC were ultimately diagnosed as having PCV. These eyes had exudative macular detachments secondary to a small caliber, polypoidal choroidal vascular abnormality or so-called polypoidal choroidal neovascularization. The clinical manifestations in the fundus varied. They included multiple, variably sized serous pigment epithelial detachments, neurosensory retinal detachment, lipid deposition, patchy atrophy of the pigment epithelium and indistinct staining from decompensation of the posterior blood-retinal barrier on fluorescein angiography. In reality, the suspected PEDs proved to be polypoidal lesions of PCV when imaged with ICG angiography. CONCLUSIONS The clinical diagnosis of CSC or PCV generally poses little challenge to the experienced retinal specialist. However, in CSC with persistent and/or recurrent exudation, a myriad of retinal pigment epithelial changes may evolve that make it difficult to differentiate these two entities. In such patients, ICG angiography is useful in differentiating CSC from PCV. An accurate clinical diagnosis is important since each of these entities, CSC and PCV, may differ in terms of their risk factors, natural course, and visual prognosis.


Current Opinion in Ophthalmology | 1995

Indocyanine-green angiography.

Jason S. Slakter; Lawrence A. Yannuzzi; David R. Guyer; John A. Sorenson; Dennis A. Orlock

&NA; Indocyanine‐green angiography represents a major advance in imaging of the choroidal circulation. Recent technical innovations have permitted this diagnostic technique to find clinical application in many chorioretinal conditions. The indocyanine‐green molecule has proven to be safe for human study. In age‐related macular degeneration, indocyanine‐green angiography may play an important role in the diagnosis of patients with occult choroidal neovascularization, leading to eventual increased efficacy with laser photocoagulation treatment. Histopathologic confirmation of a lesion noted by ICG angiography has been made. In multiple inflammatory conditions, as well as with central serous chorioretinopathy, distinct ICG patterns have emerged that may facilitate better understanding of the disease processes. With greater experience, ICG angiography may provide improved imaging, a better understanding of the pathogenesis, and new treatment approaches for various chorioretinal conditions.


Journal of Biomedical Optics | 2004

Combined multiplanar optical coherence tomography and confocal scanning ophthalmoscopy

Adrian Gh. Podoleanu; George Dobre; Radu G. Cucu; Richard B. Rosen; Patricia Garcia; Jc Nieto; D.V. Will; Ronald C. Gentile; T.O. Muldoon; Joseph B. Walsh; Lawrence A. Yannuzzi; Yale L. Fisher; Dennis A. Orlock; Rishard Weitz; John A. Rogers; Shane Dunne; Aaron B. Boxer

We demonstrate the clinical application of a multiplanar imaging system that simultaneously acquires en face (C-scan) optical coherence tomography (OCT) and the corresponding confocal ophthalmoscopic images, along with cross-sectional (B-scan) OCT at specifiable locations on the confocal image. The advantages of the simultaneous OCT and confocal acquisition as well as the challenges of interpreting the C-scan OCT images are discussed. Variations in tissue inclination with respect to the coherence wave surface alter the sampling of structures within the depth of the retina, producing novel slice orientations that are often challenging to interpret. We have evaluated for the first time the utility of C-scan OCT for a variety of pathologies, including melanocytoma, diabetic retinopathy, choroidal neovascular membrane, and macular pucker. Several remarkable new aspects of clinical anatomy were revealed using this new technique. The versatility of selective capture of C-scan OCT images and B-scan OCT images at precise points on the confocal image affords the clinician a more complete and interactive tool for 3-D imaging of retinal pathology.


Retina-the Journal of Retinal and Vitreous Diseases | 1994

Analysis of vascularized pigment epithelial detachments using indocyanine green videoangiography.

Lawrence A. Yannuzzi; Monique Hope-Ross; Jason S. Slakter; David R. Guyer; John A. Sorenson; Allen C. Ho; Sperber De; Freund Kb; Dennis A. Orlock

Background: Occult choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD) is known to occur with and without an associated serous pigment epithelial detachment (PED). Digital indocyanine green (ICG) videoangiography has been reported to provide enhanced definition of occult CNV. Methods: A total of 244 of 657 (37%) consecutive patients with AMD, with occult CNV and an associated serous PED evident on fluorescein angiographic examination, were further studied with ICG videoangiography. Results: On ICG videoangiographic examination, 9 of the 244 (4%) eyes had no evidence of underlying CNV, or essentially a pure serous PED. Each of the remaining 235 eyes (96%) had evidence of neovascularization and were defined as having a vascularized PED. These eyes were further divided into two groups, depending on the size and delineation of the neovascularization seen. Of the 235 eyes with vascularized PEDs, 89 (38%) had a solitary area of neovascularization that was well delineated, no more than one disc area in size, and defined as focal CNV. The other 146 (62%) eyes had a larger area of neovascularization, with variable delineation, defined as plaque CNV. Based on conventional guidelines, some patients were considered to be potentially eligible for laser photocoagulation treatment. Conclusion: The results of this study suggest that ICG videoangiography may be an important adjunct to the diagnosis, classification, and potential treatment of patients with AMD and occult CNV associated with a serous PED (vascularized PED).


Ophthalmology | 1996

Classification of Choroidal Neovascularization by Digital Indocyanine Green Videoangiography

David R. Guyer; Lawrence A. Yannuzzi; Jason S. Slakter; John A. Sorenson; Prut Hanutsaha; Richard F. Spaide; Stephen G. Schwartz; James M. Hirschfeld; Dennis A. Orlock

PURPOSE The majority of patients with exudative maculopathy due to age-related macular degeneration present with poorly defined or occult choroidal neovascularization (CNV) that cannot be imaged adequately by fluorescein angiography. Digital indocyanine green (ICG) videoangiography is a new technique that allows enhanced imaging of these poorly defined or occult vessels. The authors studied 1000 consecutive cases of occult CNV using digital ICG angiography to describe the various types of neovascularization observed by this technique and to determine the frequency and natural history of the various lesions. MATERIALS AND METHODS Digital ICG videoangiography was performed as described previously on 1000 consecutive eyes with occult CNV by fluorescein angiography. RESULTS One thousand consecutive eyes with occult CNV by fluorescein angiography were imaged using digital ICG videoangiography. Three morphologic types of CNV were noted by ICG videoangiography, which included focal spots, plaques (well-defined or poorly defined), and combination lesions (in which both focal spots and plaques are noted). Combination lesions can be subdivided into marginal spots (focal spots at the edge of plaques of neovascularization), overlying spots (hot spots overlying plaques of neovascularization), or remote spots (a focal spot remote from a plaque of neovascularization). The relative frequency of these lesions was as follows: there were 283 cases (29%) of focal spots; 597 cases (61%) of plaques, consisting of 265 cases (27%) of well-defined plaques and 332 cases (34%) of poorly defined plaques; and 84 cases (8%) of combination lesions, consisting of 35 cases (3%) of marginal spots, 37 cases (4%) of overlying spots, and 12 cases (1%) of remote spots. In seven additional cases (1%), a mixture of the above lesions was noted. In 13 additional eyes (1%), no lesions were noted on the ICG angiogram. The studies of 16 eyes were unreadable or unobtainable. CONCLUSIONS There are three types of CNV that can be observed by digital ICG videoangiography. Plaques are the most common type and have a poor natural history. Focal spots or hot spots are the next most frequently seen lesion and can potentially be treated by ICG-guided laser photocoagulation. Combination lesions, in which both focal spots and plaques are present, are rare. This study of 1000 consecutive cases of eyes with occult neovascularization that were imaged with digital ICG videoangiography serves to classify the various types of neovascularization observed by this technique. Digital ICG videoangiography is an important tool in better delineating eyes with occult CNV. Future studies are necessary to validate our findings.


Ophthalmology | 1997

Indocyanine green angiography of multifocal choroiditis

Jason S. Slakter; Alfonso Giovannini; Lawrence A. Yannuzzi; Baldo Scassellati-Sforzolini; David R. Guyer; John A. Sorenson; Richard F. Spaide; Dennis A. Orlock

PURPOSE The purpose of the study is to determine indocyanine green (ICG) angiographic characteristics of patients with multifocal choroiditis (MC) and to identify features that may assist in the differentiation of MC from other ocular inflammatory diseases. METHODS After complete ophthalmologic examination, fluorescein angiography and ICG angiography were performed in a series of 14 patients with MC. The ICG findings were then correlated with the clinical and fluorescein angiographic appearance of these patients to determine specific characteristics and distinguishing features of the entity. These findings then were compared with those of angiographic patterns observed in patients with ocular histoplasmosis syndrome to determine whether differentiating features could be identified. RESULTS Fourteen (50%) of the 28 eyes were found to have large hypofluorescent spots in the posterior pole on ICG angiography, which, in most cases, did not correspond to clinically or fluorescein angiographically detectable lesions. Seventeen (61%) had smaller hypofluorescent lesions (approximately 50 pm in size) in the posterior pole on the ICG study. In seven eyes exhibiting enlarged blind spots on visual field testing, ICG angiography showed confluent hypofluorescence surrounding the optic nerve. The ICG angiogram was found useful in evaluating the natural course in two patients with MC as well as a response to oral prednisone therapy in four others. The ICG angiographic findings differed from those seen in patients with ocular histoplasmosis. CONCLUSIONS Indocyanine green angiography can provide information that is not detectable by clinical or fluorescein angiographic examination in patients with MC. This information may prove useful in differentiating this condition from the ocular histoplasmosis syndrome, provide a better understanding of the natural course and progression of the disease, and provide a potential adjunct in the clinical evaluation of patients undergoing therapeutic regimens for active inflammatory lesions.

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