Christoph Scholda

Optical coherence tomographic hyperreflective foci: a morphologic sign of lipid extravasation in diabetic macular edema.

PURPOSE To analyze hyperreflective foci typically seen in diabetic macular edema (DME) in optical coherence tomography (OCT). DESIGN Prospective clinical trial. PARTICIPANTS Twelve consecutive patients with treatment-naïve, clinically significant DME. METHODS During a same-day examination, a standardized visual acuity assessment (Early Treatment of Diabetic Retinopathy Study protocol), infrared fundus imaging, color fundus photography, and biomicroscopy were performed. Additionally, all patients were scanned using Stratus, Cirrus, and Spectralis OCT and results correlated. MAIN OUTCOME MEASURES Morphologic changes secondary to DME. RESULTS In all eyes with DME, distinct hyperreflective foci distributed throughout all retinal layers were found in the OCT scans of all 3 OCT devices. These deposits could not be identified by infrared imaging, fundus photography, or biomicroscopy as long as they were not confluent. Accumulations of such foci at the border of the outer nuclear and in the outer plexiform layer were recognizable clinically as hard exudates showing the same hyperreflective features in OCT. The hyperreflectivity of these foci did not correspond with intraretinal hemorrhage, nor did the lesions cause the characteristic OCT laser beam scattering phenomena typically seen secondary to intraretinal bleedings or microaneurysms. Further, they were detected within the walls of intraretinal microaneurysms. CONCLUSIONS Well-demarcated, hyperreflective foci were identified in the retina of patients with DME. The deposits were located within walls of intraretinal microaneurysms and scattered throughout all retinal layers, forming confluent plaques in the outer plexiform layer. It is suggested that the foci represent extravasated lipoproteins and/or proteins being a very early subclinical barrier breakdown sign in DME.

A Systematic Correlation of Angiography and High-Resolution Optical Coherence Tomography in Diabetic Macular Edema

PURPOSE To correlate leakage patterns in fluorescein angiography (FA) images and retinal morphologic features in high-definition optical coherence tomography (HD OCT) images in diabetic macular edema. DESIGN Prospective pilot study and case series. PARTICIPANTS Nine consecutive patients (10 eyes) with diabetic macular edema. METHODS All patients were examined using FA (HRA 2; Heidelberg Engineering) and HD OCT (Carl Zeiss Meditec; resolution, 512x128 pixels, 5.8x5.8 mm, and high-resolution scans consisting of 4096 A scans) on the same day. Using Adobe Photoshop (CS2 Version 9.0; Adobe Systems Incorporated, San Jose, CA) a grid containing 15x7 fields was superimposed on the HD OCT en face image and a late-phase FA image according to retinal landmarks. In each patient, a standardized analysis of 105 subfields was performed to provide a characterization of the type of vascular leakage in FA and the associated retinal morphologic changes in corresponding locations. MAIN OUTCOME MEASURES Angiographic leakage type and structural alteration in retinal morphologic features in OCT. RESULTS There was a high consistency between FA and OCT in the petaloid pattern of hyperfluorescence that correlated with the presence of large cystic spaces in the outer nuclear layer (ONL) and the outer plexiform layer (OPL) with or without subretinal fluid in 30.4% and 69.6% of graded fields, respectively. A honeycomblike pattern of hyperfluorescence was associated with swelling and cystic spaces in ONL, OPL, the inner nuclear, and the inner plexiform layer in 71.4% of graded fields. Diffuse patterns of hyperfluorescence did not correlate with characteristic retinal changes in HD OCT, but rather showed diversity in the type of morphologic alteration. The presence of central fluid pooling, such as subretinal fluid, could be identified only by HD OCT and not by FA. CONCLUSIONS In the examined patients, a petaloid pattern and a honeycomb pattern of hyperfluorescence observed in FA were found to correlate to characteristic changes in HD OCT, whereas a diffuse leakage pattern was associated with nonuniform changes in retinal morphologic features. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Orbital helical computed tomography in the diagnosis and management of eye trauma

OBJECTIVE To prospectively determine the accuracy of helical computed tomography (CT) and multiplanar reconstruction and its value in surgical planning for the management of ocular trauma with suspected intraocular and orbital foreign bodies using surgical and clinical follow-up findings as the gold standard. DESIGN Prospective, observational case series. PARTICIPANTS Thirty-six patients with ocular trauma and suspected foreign bodies were studied. INTERVENTION All patients were examined using a standardized scanning protocol with helical CT direct scanning in the axial plane and multiplanar reconstruction of coronal and sagittal planes. MAIN OUTCOME MEASURES The images were analyzed for the presence and number of intraocular and orbital foreign bodies, anatomic location, and foreign body size. The surgical and clinical follow-up findings (contact lens examination, gonioscopy, indirect ophthalmoscopy and scleral depression, perimetry, color testing, measurement of size) were used as the gold standard to which the image results were compared. RESULTS Helical CT showed a single intraocular foreign body in 14 patients, a single orbital foreign body in 9 patients, and multiple orbital foreign bodies in 2 patients. Intraocular or orbital foreign bodies were excluded in 11 patients. Twenty foreign bodies were correlated with surgical results. Surgical and clinical follow-up findings were in agreement with helical CT results regarding the detection and determination of the number of presumed foreign bodies. Localization to intraocular versus orbital compartment and proximity to the optic nerve was accurate in all patients. Determination of size of the foreign bodies on the helical CT images was reliable and repeatable. CONCLUSIONS Helical CT axial scanning with multiplanar reconstruction is accurate at detecting and localizing intraocular and orbital metallic, glass, and stone foreign bodies. This imaging method aids the surgeon in choosing the surgical approach to retained intraocular and orbital foreign bodies.

Ultrahigh resolution optical coherence tomography of macular holes.

Purpose: To evaluate ultrahigh resolution optical coherence tomography (UHR OCT) for visualization of intraretinal layers, especially the photoreceptor inner segment and outer segment layers, in eyes with macular holes and after surgical intervention. Methods: An UHR OCT system based on a titanium:sapphire laser was used, enabling in vivo cross-sectional retinal imaging with 3-&mgr;m axial resolution. Typical, representative tomograms of 5 of 48 eyes from 36 patients demonstrated the potential of UHR OCT to detect morphologic changes in different stages of full-thickness macular holes and changes induced by surgical intervention. Results: UHR OCT could detect subtle intraretinal changes in macular hole formation. Unprecedented visualization of photoreceptor impairment was achieved that appeared to be more extensive than the hole itself. Postoperatively, clinically closed holes showed restoration of the photoreceptor inner and outer segment layers of various extents, with residual disease in some eyes. Conclusion: In macular holes, UHR OCT allows for detection of even small morphologic changes of the retinal layers, especially the photoreceptor inner and outer segment layers. Therefore, it also represents a superior method to monitor the effect of surgical interventions. Preoperative photoreceptor impairment and the degree of postoperative restoration could possibly be associated with visual function. Hence, UHR OCT could lead to better understanding of macular hole pathogenesis and to more accurate disease prognosis.

In Vivo Retinal Morphology after Grid Laser Treatment in Diabetic Macular Edema

PURPOSE To analyze immediate in vivo intraretinal morphologic changes secondary to standardized grid photocoagulation using spectral domain optical coherence tomography (SD OCT). DESIGN Prospective clinical trial. PARTICIPANTS Thirteen consecutive patients with treatment-naïve clinically significant diabetic macular edema (DME). METHODS Before and 1 day after standardized grid photocoagulation using the PASCAL system (Pattern Scan Laser, OptiMedica Corporation, Santa Clara, CA), Spectralis OCT (Heidelberg Engineering, Heidelberg, Germany) examinations based on an eye-tracking system, infrared fundus imaging, color fundus photography, and biomicroscopy were performed. A standardized visual acuity assessment (Early Treatment Diabetic Retinopathy Study protocol) and fluorescein angiography were performed at baseline. MAIN OUTCOME MEASURES Morphologic changes secondary to grid laser treatment. RESULTS One day after laser therapy, immediate morphologic alterations of only the outer retinal layers, that is, the retinal pigment epithelium (RPE), the photoreceptor layer (PRL), and the outer nuclear layer (ONL), were observed. The shape of the laser-induced lesions did not show a sagittal alteration pattern throughout all 3 of the layers, however, but rather seemed to follow an oblique pathway throughout the ONL, changing direction at the level of the external limiting membrane and proceeding sagittally through the PRL and RPE. These morphologic changes also induced biometric changes, such as a decrease in central retinal thickness combined with local thickening at the lesion site, especially in the PRL. CONCLUSIONS Spectral domain optical coherence tomography provides new insight into the immediate morphologic changes after laser treatment using the PASCAL laser system. Standardized grid photocoagulation induces characteristic homogenous alteration in the neurosensoric retinal layers. Biometric changes, indicating an immediate effect, were observed within 1 day after treatment.

Different techniques of extracapsular cataract extraction: bacterial contamination during surgery

This study was performed to investigate the correlation between the contamination of the anterior chamber and the technique of extracapsular cataract extraction (ECCE). Three different methods were used: uncomplicated planned ECCE, phacoemulsification involving suturing method, and sutureless technique. All patients had posterior chamber intraocular lenses implanted. Two hundred and thirty consecutive patients were included in this prospective study, and preoperative smears of the conjunctiva and intraoperative aspirates of the anterior chamber were investigated. Samples of the aqueous humor were taken at the beginning and at the end of the operation. Cultures were incubated and held for 14 days. More than 71% of the preoperative smears were contaminated by coagulase-negative staphylococci, the most commonly isolated bacteria. However, 27% of the patients had culture-positive anterior chamber aspirates intraoperatively, also with coagulase-negative staphylococci as the most frequent organisms. In no case did postoperative endophthalmitis develop. Preliminary results in a small population show that the contamination of the aqueous humor is statistically significantly less frequent if the cataract extraction is performed by phacoemulsification than if it is done without phacoemulsification. Another interesting finding is that anterior chamber contamination is not significantly more frequent, if a sutureless technique is used for cataract surgery.

Repeated intravitreal bevacizumab (Avastin®) treatment of persistent new vessels in proliferative diabetic retinopathy after complete panretinal photocoagulation

Acta Ophthalmol. 2011: 89: 76–81

Effect of retinal photocoagulation on intraretinal lipid exudates in diabetic macular edema documented by optical coherence tomography.

PURPOSE To study the changes in the distribution and morphologic features of intraretinal microexudates after macular photocoagulation. DESIGN Prospective cohort study. PARTICIPANTS Thirteen treatment-naïve patients with clinically significant macular edema in type 2 diabetes. METHODS Patients were treated with focal macular photocoagulation. Changes in the localization of hyperreflective foci were analyzed by spectral domain (SD) optical coherence tomography (OCT) during follow-up at day 1, week 1, and months 1, 2, 3, and 4 in defined areas. Further, fundus photography and infrared imaging were performed at all visits and findings were correlated to OCT results. MAIN OUTCOME MEASURES Changes in retinal morphologic features detected in OCT. RESULTS A dynamic change in the distribution pattern of hyperreflective foci was observed over 4 months after the photocoagulation. With the decrease of retinal thickness, the dots either resolved completely or became confluent at the apical border of the outer nuclear layer, and finally formed ophthalmoscopically detectable hard exudates during extended follow-up. In the event of retinal thickening despite laser treatment, the hyperreflective dots maintained their previous distribution throughout all retinal layers. As a fourth response, dissemination of plaques of hard exudates into multiple, separate, hyperreflective foci were detected. CONCLUSIONS Hyperreflective foci in the retina seem to represent precursors or components of hard exudates. Their specific localization depends greatly on the presence of microvascular extravasation and intraretinal fluid accumulation. Retinal photocoagulation has a major impact on retinal edema and subsequently on the distribution of intraretinal lipid deposits. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Primary silicone oil tamponade without retinopexy in highly myopic eyes with central macular hole detachments.

Background: In highly myopic macular hole central retinal detachments, the ideal treatment is still under discussion. In our study, we analyzed anatomic and functional outcomes for eyes undergoing vitrectomy with primary silicone oil filling without central photocoagulation, using the oil as inductor and scaffold for glial closure of the causative macular hole. Methods: Eleven patients with central macular hole detachments and myopia ranging from −10.0 to −23.0 diopters underwent vitrectomy and primary silicone oil filling without laser photocoagulation of the central retina. After at least 3 months (mean ± SD, 5.2 ± 2.0 months), the oil was removed from all eyes. Results: In all eyes, the retina was attached by the first postoperative day and remained attached after silicone oil removal until the end of the follow-up period. No severe intra- or postoperative complications were noted. Visual acuity increased in 7 (63.6%) of 11 eyes, remained unchanged in 3 (27.3%) of 11, and deteriorated in 1 (9.1%) of 11. Conclusion: Vitrectomy plus primary silicone oil tamponade without endophotocoagulation is an effective method to treat central macular hole detachments in highly myopic eyes.

Evaluation of intraocular foreign bodies by spiral computed tomography and multiplanar reconstruction

OBJECTIVE This study aimed to evaluate the ability of spiral computed tomography (CT) and multiplanar reconstruction in the assessment of intraocular foreign bodies. DESIGN The study design was experimental. MATERIAL Three foreign bodies (metal, glass, and plastic) implanted into the globe of a cadaveric head were studied. INTERVENTION Spiral CT in the axial plane was used. Beam collimation and table increment were both 3 mm, whereby overlapping axial slices were reconstructed at 1-mm intervals. The data were transferred to a workstation, and reconstructions in the coronal and sagittal plane were performed. MAIN OUTCOME MEASURES The ability to detect and evaluate localization, shape, and size of the foreign bodies in all three imaging planes was assessed. RESULTS All foreign bodies were detected in the axial and in both reconstructed planes. The metal foreign body caused imaging artifacts in the axial plane. In the reconstructed planes. imaging artifacts were less severe, and evaluation of localization and shape was improved. Glass and plastic foreign bodies were well seen in all planes, and shape and localization were well demonstrated. Appropriate window settings improved determination of size of the different foreign bodies. CONCLUSIONS Spiral CT of the orbit and multiplanar reconstruction offers a promising tool for evaluation of intraocular foreign bodies. Advantages of spiral CT compared to conventional CT are data acquisition in only one axial plane; shortened examination time; reduced radiation exposure; reduced imaging artifacts from metallic foreign bodies in the reconstructed planes; and demonstration of localization, shape, and size of the foreign body in three imaging planes.