-
Current Opinion in Ophthalmology May 2017Visualization remains a critical factor in successful ocular surgery.Here we review new technology that has the potential to allow for safer and more efficient retinal... (Review)
Review
PURPOSE OF REVIEW
Visualization remains a critical factor in successful ocular surgery.Here we review new technology that has the potential to allow for safer and more efficient retinal surgery.
RECENT FINDINGS
Vitreoretinal surgery poses unique visualization challenges such as the need for specialized optical systems and the delicate and microscopic features of retinal structures. Better retinal visualization allows for new approaches to increasingly complex retinal cases. Wide-angle viewing has allowed stereopic visualization of the peripheral retina. Improved lighting systems have shown better safety profiles and can facilitate bimanual techniques. The potential to improve surgical decision making has been shown with intraoperative imaging such as optical coherence tomography.
SUMMARY
Although some of the benefits of these developments have yet to be proven, improved technology for visualization during retinal surgery will hopefully allow for safer and more efficient surgeries.
Topics: Humans; Retina; Tomography, Optical Coherence; Vitreoretinal Surgery; Vitreous Body
PubMed: 28306625
DOI: 10.1097/ICU.0000000000000368 -
Ophthalmology Feb 2018Despite posterior vitreous detachment being a common ocular event affecting most individuals in an aging population, there is little consensus regarding its precise...
PURPOSE
Despite posterior vitreous detachment being a common ocular event affecting most individuals in an aging population, there is little consensus regarding its precise anatomic definition. We investigated the morphologic appearance and molecular composition of the posterior hyaloid membrane to determine whether the structure clinically observed enveloping the posterior vitreous surface after posterior vitreous detachment is a true basement membrane and to postulate its origin. Understanding the relationship between the vitreous (in both its attached and detached state) and the internal limiting membrane of the retina is essential to understanding the cause of rhegmatogenous retinal detachment and vitreoretinal interface disorders, as well as potential future prophylactic and treatment strategies.
DESIGN
Clinicohistologic correlation study.
PARTICIPANTS
Thirty-six human donor globes.
METHODS
Vitreous bodies identified to have posterior vitreous detachment were examined with phase-contrast microscopy and confocal microscopy after immunohistochemically staining for collagen IV basement membrane markers, in addition to extracellular proteins that characterize the vitreoretinal junction (fibronectin, laminin) and vitreous gel (opticin) markers. The posterior retina similarly was stained to evaluate the internal limiting membrane. Findings were correlated to the clinical appearance of the posterior hyaloid membrane observed during slit-lamp biomicroscopy after posterior vitreous detachment and compared with previously published studies.
MAIN OUTCOME MEASURES
Morphologic appearance and molecular composition of the posterior hyaloid membrane.
RESULTS
Phase-contrast microscopy consistently identified a creased and distinct glassy membranous sheet enveloping the posterior vitreous surface, correlating closely with the posterior hyaloid membrane observed during slit-lamp biomicroscopy in patients with posterior vitreous detachment. Immunofluorescent confocal micrographs demonstrated the enveloping membranous structure identified on phase-contrast microscopy to show positive stain results for type IV collagen. Immunofluorescence of the residual intact internal limiting membrane on the retinal surface also showed positive stain results for type IV collagen.
CONCLUSIONS
The results of this study provide immunohistochemical evidence that the posterior hyaloid membrane is a true basement membrane enveloping the posterior hyaloid surface. Because this membranous structure is observed only after posterior vitreous detachment, the results of this study indicate that it forms part of the internal limiting membrane when the vitreous is in its attached state.
Topics: Adult; Aged; Aged, 80 and over; Basement Membrane; Collagen; Female; Humans; Imaging, Three-Dimensional; Immunohistochemistry; Male; Microscopy, Acoustic; Microscopy, Confocal; Middle Aged; Prospective Studies; Vitrectomy; Vitreous Body; Vitreous Detachment
PubMed: 28867131
DOI: 10.1016/j.ophtha.2017.08.001 -
Retina (Philadelphia, Pa.) Aug 2022To evaluate the degenerative findings including cistern formation in the premacular vitreous using optical coherence tomography.
PURPOSE
To evaluate the degenerative findings including cistern formation in the premacular vitreous using optical coherence tomography.
METHODS
A novel enhanced vitreous imaging method by which four A-scans at each position were averaged before the Fourier transform increased the image quality per frame so that subsequent image registration for averaging could occur. Analysis of B-scans and volume-rendered images of eyes in subjects of various ages was performed.
RESULTS
There were 43 eyes of 23 subjects ranging in age from 23 to 68 years. The texture in the vitreous images suggests specific orientations of the vitreous fibers in the macular region; there were fibers circumferential to the retina immediately anterior to the premacular bursa. The pattern of the vitreous fibers seemed less well-defined internal to the zone of circumferential fibers. In younger eyes, there were striations oriented in a roughly inferior to superior direction in this zone. In older eyes, there were striations in the same orientation but actually were alternating zones of vitreous synchysis and syneresis. In these same eyes, numerous cisterns appeared at various levels in the vitreous gel. With extensive vitreous condensation and synchysis, definition of the premacular bursa was lost.
CONCLUSION
With this novel method of enhanced vitreous imaging, the vitreous seemed to have stereotypic patterns of degeneration. The formation of vitreous syneresis and synchysis may be related to organization architecture of the vitreous, including the pattern of vitreous collagen deposition, and the effects of eye motion through decades of time.
Topics: Adult; Aged; Healthy Volunteers; Humans; Middle Aged; Retina; Tomography, Optical Coherence; Vitreous Body; Young Adult
PubMed: 35333841
DOI: 10.1097/IAE.0000000000003474 -
Disease Markers 2021The vitreous body is an important part of the ocular body fluid. A foldable capsular vitreous body (FCVB) is designed to treat chronic adverse complications in severe...
BACKGROUND
The vitreous body is an important part of the ocular body fluid. A foldable capsular vitreous body (FCVB) is designed to treat chronic adverse complications in severe ocular trauma and silicone oil-dependent eyes. This study is aimed at investigating a method for implanting an FCVB, its postoperative efficacy, and clinical value.
METHODS
A retrospective analysis was performed on data from 18 patients who underwent vitrectomy and FCVB implantation for severe ocular trauma and silicone oil-dependent eyes between March 2019 and May 2020. All treated eyes underwent clinical examinations involving the best-corrected visual acuity, intraocular pressure, FCVB position, anterior segment photography, and wide-angle fundus photography regularly after surgery.
RESULTS
Eighteen eyes from 18 patients were enrolled in this study. A total of 2.00-4.20 (3.46 ± 0.78) ml of silicone oil were injected into the FCVB during surgery. The patients were followed up at 1, 2, and 4 weeks and 3, 6, and 12 months after surgery. Twelve months after surgery, visual acuity improved in 7 (38.89%) eyes. In contrast, 10 (55.56%) eyes showed no obvious improvement, and 1 (5.56%) eye had decreased vision. Intraocular pressure at 12 months was 10.13 ± 3.52 mmHg, which was comparable to that before the surgery ( = 0.38, = 0.71). The anterior chamber depth examined by slit lamp was 2.00-3.00 cornea thickness (CT) in 7 eyes, 1.00-2.00 CT in 2 eyes, and <1.00 CT in one eye. The anterior chamber disappeared in eight eyes. There were eight eyes with clear cornea, four eyes with localized opacity, and two eyes with obvious gray-white opacity. There was no case of severe FCVB deflection, rupture, or exposure during the observation period.
CONCLUSION
FCVB implantation is an effective and safe treatment for eyes with severe ocular trauma and silicone oil-dependent eyes. It may support retinal reattachment, slow down eyeball atrophy, reduce the risk of chronic adverse complications such as corneal endothelial decompensation, and maintain intraocular pressure and preoperative visual function.
Topics: Adult; Aged; Female; Humans; Male; Middle Aged; Retrospective Studies; Silicone Oils; Treatment Outcome; Vitrectomy; Vitreous Body
PubMed: 34987675
DOI: 10.1155/2021/6575195 -
PloS One 2021The systemic organ involvement of SARS-CoV-2 needs to be thoroughly investigated including the possibility of an ocular reservoir in humans. To examine retinal tissues...
BACKGROUND/OBJECTIVES
The systemic organ involvement of SARS-CoV-2 needs to be thoroughly investigated including the possibility of an ocular reservoir in humans. To examine retinal tissues and vitreous for histopathology and SARS-CoV-2 presence with regard to possible effects on the human retina and/ or vitreous. We performed histopathological analyses and quantitative (q)RT-PCR-testing for SARS-CoV-2 RNA on retinal tissues and vitreous of COVID-19 postmortem donors.
SUBJECTS/METHODS
Included in this study were 10 eyes of 5 deceased COVID-19 patients. The diagnosis of SARS-CoV-2 infection was confirmed via pharyngeal swabs and broncho-alveolar fluids. The highest level of personal protective equipment (PPE) and measures was employed during fluid-tissue procurement and preparation. Histopathological examinations and qRT-PCR-testing were carried out for all retinal tissues and vitreous fluids.
RESULTS
The histopathological examinations revealed no signs of morphologically identifiable retinal inflammation or vessel occlusions based on hematoxylin and eosin stains. By qRT-PCRs, we detected no significant level of viral RNA in human retina and vitreous.
CONCLUSIONS
In this study, no significant level of SARS-CoV-2-RNA was detected in the human retinal and vitreous fluid samples of deceased COVID-19 patients. Histopathological examinations confirmed no morphological sign of damage to retinal vasculature or tissues. Further studies are needed to confirm or refute the results.
Topics: Autopsy; COVID-19; COVID-19 Nucleic Acid Testing; Humans; RNA, Viral; Retina; SARS-CoV-2; Vitreous Body
PubMed: 33984050
DOI: 10.1371/journal.pone.0251682 -
Journal of Analytical Toxicology Feb 2021Vitreous humor is a potential alternative matrix for postmortem toxicology drug screens when peripheral blood is unavailable. It is easily and reliably collected and may...
Vitreous humor is a potential alternative matrix for postmortem toxicology drug screens when peripheral blood is unavailable. It is easily and reliably collected and may not suffer from the same postmortem redistribution as seen in blood. Here, we compared the concentrations of 7 acidic drugs (acetaminophen, ibuprofen, naproxen, salicylic acid, carbamazepine, phenobarbital and phenytoin) in peripheral blood and vitreous fluid collected in 89 autopsy cases. Analysis was done by high-performance liquid chromatography with diode-array detection. Overall, we found that vitreous drug concentrations were significantly lower than peripheral blood with median vitreous to peripheral blood (V/PB) ratios ranging from 0.0 to 0.6 (mean, 0.1-0.6). The correlations between the concentrations of over-the-counter analgesics in peripheral blood versus vitreous fluid were poor, with acetaminophen exhibiting the best linearity (R2 = 0.72). The antiepileptic drugs (carbamazepine, phenytoin and phenobarbital) exhibited good correlations between peripheral blood and vitreous humor, with all exhibiting an R2 ≥ 0.95. Overall, we have demonstrated the potential of vitreous fluid as an alternative matrix for the detection of select acidic drugs.
Topics: Autopsy; Benzodiazepines; Body Fluids; Forensic Toxicology; Humans; Pharmaceutical Preparations; Postmortem Changes; Substance Abuse Detection; Vitreous Body
PubMed: 31696920
DOI: 10.1093/jat/bkz076 -
Investigative Ophthalmology & Visual... Mar 2023Age-related macular degeneration (AMD) is the leading cause of visual impairment worldwide. In this study, we aimed to investigate the vitreous humor metabolite profiles...
PURPOSE
Age-related macular degeneration (AMD) is the leading cause of visual impairment worldwide. In this study, we aimed to investigate the vitreous humor metabolite profiles of patients with intermediate AMD using untargeted metabolomics.
METHODS
We performed metabolomics using high-resolution liquid chromatography mass spectrometry on the vitreous humor of 31 patients with intermediate AMD and 30 controls who underwent vitrectomy for epiretinal membrane with or without cataract surgery. Univariate analyses after false discovery rate correction were performed to discriminate the metabolites and identify the significant metabolites of intermediate AMD. For biologic interpretation, enrichment and pathway analysis were conducted using MetaboAnalyst 5.0.
RESULTS
Of the 858 metabolites analyzed in the vitreous humor, 258 metabolites that distinguished patients with AMD from controls were identified (P values < 0.05). Ascorbic acid and uric acid levels increased in the AMD group (all P values < 0.05). The acyl carnitines, such as acetyl L-carnitine (1.37-fold), and fatty amides, such as anandamide (0.9-fold) and docosanamide (0.67-fold), were higher in patients with intermediate AMD. In contrast, nicotinamide (-0.55-fold), and succinic acid (-1.69-fold) were lower in patients with intermediate AMD. The metabolic pathway related oxidation of branched chain fatty acids and carnitine synthesis showed enrichment.
CONCLUSIONS
Multiple metabolites related to fatty amides and acyl carnitine were found to be increased in the vitreous humor of patients with intermediate AMD, whereas succinic acid and nicotinamide were reduced, suggesting that altered metabolites related to fatty amides and acyl carnitines and energy metabolism may be implicated in the etiology of AMD.
Topics: Humans; Amides; Carnitine; Macular Degeneration; Niacinamide; Succinates; Vitreous Body
PubMed: 36939720
DOI: 10.1167/iovs.64.3.28 -
Topics in Magnetic Resonance Imaging :... Apr 2022Magnetic resonance imaging (MRI) is increasingly used in postmortem fetal imaging. Several factors influence the quality of MRI in this setting, such as small size,...
OBJECTIVES
Magnetic resonance imaging (MRI) is increasingly used in postmortem fetal imaging. Several factors influence the quality of MRI in this setting, such as small size, autolytic and maceration changes, and temperature. Knowing the fetal temperature at the time of scanning can improve the MRI interpretation. Temperature can be calculated using diffusion-weighted imaging with measurements of the apparent diffusion coefficient (ADC) in the cerebrospinal fluid (CSF). However, this is complicated by small ventricle size and hemorrhage and, therefore, may be unreliable in postmortem imaging. The current study evaluated the feasibility and reliability of using the ADC for temperature measurements of the vitreous body compared to that of CSF.
MATERIALS AND METHODS
Two lambs were scanned postmortem at five different time points over 28 hours. Furthermore, 10 stillborn fetuses were scanned once, at 4 to 62 hours after birth. The temperature was measured with a digital thermometer and calculated using the ADCs of the vitreous body (lambs and fetuses) and CSF (fetuses).
RESULTS
There was an excellent correlation between measured and calculated temperatures in vitreous bodies of lambs (r = 0.997, P < 0.001) and fetuses (r = 0.970, P < 0.001). The correlation between measured and calculated temperatures in the CSF was poor (r = 0.522, P = 0.122).
CONCLUSION
The calculation of the temperature based on the ADC of the vitreous body is feasible and reliable for postmortem fetal imaging.
Topics: Animals; Sheep; Humans; Vitreous Body; Temperature; Reproducibility of Results; Diffusion Magnetic Resonance Imaging; Fetus; Magnetic Resonance Spectroscopy; Magnetic Resonance Imaging
PubMed: 36269228
DOI: 10.1097/RMR.0000000000000295 -
Indian Journal of Ophthalmology Apr 2022Diabetic membranes are always a challenge for a surgeon because of sticky nature and chances of iatrogenic break while removing.
BACKGROUND
Diabetic membranes are always a challenge for a surgeon because of sticky nature and chances of iatrogenic break while removing.
PURPOSE
To demonstrate a safe reverse swiss roll technique to dissect diabetic vitreous membranes.
SYNPOSIS
Approaches and techniques for membrane dissection are segmentation, delamination and en-bloc dissection using various types of instruments and illumination. With vitreous cutte, picks and scissors, surgical steps are traditionallu performed by using classic lift and shave technique. After identifying the plane, tissue is lifted and then cut, which puts the retina at risk of break because of traction and active suction. Such a threat can be reduced by placing the cutter above the membrane thereby having the membrane itseld acting as a protective cushion to the retina. Port here, unlike lift and shave technique, doesn't face the edge of membrane but is exactly 180 degree opposite and membrane curls into port because of suction. Also, hemostasis is maintained by continuous aspiration and cutting as the instrument is moved side to side, retracting from the edge.
HIGHLIGHTS
Reverse swiss roll technique is safer compared to lift and shave because of the safety cushion of the membrane between the port and the retina. There is inherently less chances of retinal break because the active suction from the port is directed away from the retina. The technique also minimises traction and localised pull on the atrophic macula.
VIDEO LINK
https://youtu.be/WNnSsP69ZLw.
Topics: Diabetes Mellitus; Humans; Retinal Perforations; Switzerland; Vitrectomy; Vitreous Body
PubMed: 35326086
DOI: 10.4103/ijo.IJO_631_22 -
BMJ Case Reports Jan 2017
Topics: Adult; Athletic Injuries; Eye Injuries; Humans; Male; Vitreous Body; Vitreous Hemorrhage; Wounds, Nonpenetrating
PubMed: 28052952
DOI: 10.1136/bcr-2016-218303