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Scientific Reports Oct 2023We conducted a study to assess the pressure difference between the aqueous and vitreous humors in rabbit eyes using a direct intraocular pressure (IOP) measurement...
We conducted a study to assess the pressure difference between the aqueous and vitreous humors in rabbit eyes using a direct intraocular pressure (IOP) measurement method. A micro-optic-fiber pressure sensor was utilized for this purpose. Preliminary experiments with enucleated porcine eyes confirmed the sensor's accuracy in measuring both aqueous and vitreous humor pressure. The main study involved six healthy albino rabbits, where the sensor measured the pressure in the anterior chamber (aIOP) and posterior vitreous-cavity (pIOP). These measurements were compared to aIOP values obtained through rebound tonometry. Additionally, pre- and postoperative pressure comparisons were made after performing a vitrectomy. Results revealed a significant disparity between aqueous and vitreous humor pressures. Prior to vitrectomy, pIOP was 22.8 mmHg, over twice as high as aIOP (11.0 mmHg), but decreased to a similar level following the procedure. Comparison between the sensor measurements and rebound tonometry showed agreement in aIOP values. In conclusion, our study demonstrates that vitreous humor pressure is consistently higher than aqueous humor pressure, reaching the upper limit of normal IOP. Furthermore, vitrectomy effectively reduces pIOP, aligning it with aIOP. These findings contribute valuable insights into intraocular pressure dynamics and have implications for clinical interventions targeting ocular pressure regulation.
Topics: Animals; Swine; Rabbits; Vitreous Body; Intraocular Pressure; Vitrectomy; Tonometry, Ocular; Aqueous Humor
PubMed: 37880357
DOI: 10.1038/s41598-023-45616-z -
Science Advances Nov 2023Choroidal melanoma, a common intraocular malignant tumor, relies on local radiotherapy and enucleation for treatment. However, cancer recurrence and visual impairment...
Choroidal melanoma, a common intraocular malignant tumor, relies on local radiotherapy and enucleation for treatment. However, cancer recurrence and visual impairment remain important challenges. Here, a therapeutic artificial vitreous body (AVB) hydrogel based on tetra-armed poly(ethylene glycol) was developed to control the recurrence of choroidal melanoma and preserve vision after vitrectomy. AVB loaded with melphalan (Mel) and anti-programmed cell death ligand-1 (αPDL1), was injected after surgical resection in the choroidal melanoma mouse model. Afterwards, the sequentially released Mel and αPDL1 from AVB could achieve a synergistic antitumor effect to inhibit tumor recurrence. AVB with similar physical properties to native vitreous body could maintain the normal structure and visual function of eye after vitrectomy, which has been evidenced by standard examinations of ophthalmology in the mouse model. Thus, the immunotherapeutic AVB may be a promising candidate as an infill biomaterial to assist surgical treatment of intraocular malignant tumors.
Topics: Animals; Mice; Vitreous Body; Vitrectomy; Hydrogels; Neoplasm Recurrence, Local; Melanoma; Choroid Neoplasms; Melphalan; Immunotherapy
PubMed: 37910617
DOI: 10.1126/sciadv.adh1582 -
Indian Journal of Ophthalmology Oct 2023Gaucher disease is a rare genetic disorder caused by a deficiency in the enzyme glucocerebrosidase, which impairs the body's ability to break down certain fats. This...
BACKGROUND
Gaucher disease is a rare genetic disorder caused by a deficiency in the enzyme glucocerebrosidase, which impairs the body's ability to break down certain fats. This leads to the accumulation of glucosyl sphingosine and glucosyl ceramide in the liver, spleen, and bone marrow. Gaucher disease has two major types: nonneuropathic (Type 1) and neuropathic (Type 2 and Type 3). Gaucher disease can have various ophthalmologic manifestations, particularly in Type 3, including posterior segment abnormalities, such as vitreous opacities, condensations, and/or preretinal white dots. We present a case of a patient with Gaucher disease Type 3 who had severe bilateral vitreous and extensive retinal deposits, leading to challenges during surgery.
PURPOSE
This video reports surgical outcomes for an uncommon ophthalmologic manifestation in a patient with Gaucher disease Type 3. We focus on the challenges and results of surgery for severe bilateral vitreous and extensive retinal deposits.
SYNOPSIS
A 16-year-old female patient with a history of Gaucher's disease since birth presented with a one-year history of blurred vision in both eyes. Her best-corrected visual acuity was 20/200 in the right eye and 20/100 in the left eye, as measured by Snellen's chart. Intraocular pressure was normal in both eyes, and anterior segment examinations were unremarkable. However, fundus evaluation revealed extensive vitreous deposits that obscured the details of the fundus. Additionally, an epiretinal membrane was observed over the macula in both eyes. Optical coherence tomography (OCT) confirmed the presence of deposits in the vitreous cavity and on the surface of the retina. The patient underwent pars plana vitrectomy with epiretinal membrane removal. A transconjunctival 23-G pars plana vitrectomy was performed to the extent possible. Multiple instruments were used to remove the fluffy vitreous deposits, as they were extremely adherent to the underlying surface of the retina, and brilliant blue dye was used to stain the internal limiting membrane. The epiretinal membrane and internal limiting membrane were removed from the macular area, and the entire cassette fluid was sent for histopathological examination to identify Gaucher cells. At one week postoperative, the patient's visual acuity improved to 20/125 in the right eye, and the fundus picture showed a cleared macular area. OCT showed a reduction in deposits over the retina. The histopathological examination revealed crumpled, barrel-like cytoplasm with an oval nucleus in a hemorrhagic background, suggestive of Gaucher cells.
HIGHLIGHTS
Early detection and treatment of ocular manifestations of Gaucher's disease are important to prevent permanent damage to vision. An ophthalmological assessment involving a dilated fundus examination and optical coherence tomography can facilitate early diagnosis and follow-up of ocular manifestations. Timely surgery may be required to preserve functional vision in patients with severe ocular disease.
VIDEO LINK
https://youtu.be/KR-kfgfDoqM.
Topics: Humans; Female; Adolescent; Gaucher Disease; Epiretinal Membrane; Retina; Vitrectomy; Retinal Degeneration; Tomography, Optical Coherence; Vision Disorders; Early Diagnosis
PubMed: 37787254
DOI: 10.4103/IJO.IJO_996_23 -
American Journal of Ophthalmology Sep 2023The aim of this study is to report the clinical characteristics, causative organisms, and treatment outcomes in patients presenting with endophthalmitis related to XEN...
PURPOSE
The aim of this study is to report the clinical characteristics, causative organisms, and treatment outcomes in patients presenting with endophthalmitis related to XEN stent implants.
DESIGN
Retrospective, noncomparative consecutive case series.
METHODS
Clinical and microbiologic review was performed for 8 patients presenting to the Bascom Palmer Eye Institute Emergency Room between 2021 and 2022 with XEN stent-related endophthalmitis. Data collected included clinical characteristics of patients at presentation, organisms identified in ocular cultures, treatments received, and visual acuity at last follow-up.
RESULTS
The current study included 8 eyes from 8 patients. All cases of endophthalmitis occurred >30 days after implantation of the XEN stent. At the time of presentation, there were external exposures of the XEN stent in 4 of 8 patients. Five of the 8 patients had positive intraocular cultures, all of which were variants of staphylococcus and streptococcus species. Management included intravitreal antibiotics in all patients, explantation of the XEN stent in 5 patients (62.5%), and pars plana vitrectomy in 6 patients (75%). At last follow-up, 6 of the 8 patients (75%) had a visual acuity of hand motion or worse.
CONCLUSIONS
Endophthalmitis in the setting of XEN stents results in poor visual outcomes. The most common causative organisms are staphylococcus or streptococcus species. At time of diagnosis, prompt treatment with broad-spectrum intravitreal antibiotics is recommended. Consideration can be made to explant the XEN stent and perform early pars plana vitrectomy.
Topics: Humans; Retrospective Studies; Eye Infections, Bacterial; Endophthalmitis; Vitreous Body; Vitrectomy; Anti-Bacterial Agents; Stents
PubMed: 37059319
DOI: 10.1016/j.ajo.2023.04.006 -
Journal of Visualized Experiments : JoVE Jan 2024Vitreoretinal lymphoma (VRL) represents an aggressive lymphoma, often categorized as primary central nervous system diffuse large B-cell lymphoma. To diagnose VRL,...
Vitreoretinal lymphoma (VRL) represents an aggressive lymphoma, often categorized as primary central nervous system diffuse large B-cell lymphoma. To diagnose VRL, specimens such as vitreous humor and, more recently, aqueous humor are collected. Diagnostic testing for VRL on these specimens includes cytology, flow cytometry, and molecular testing. However, both cytopathology and flow cytometry, along with molecular testing using cellular DNA, necessitate intact whole cells. The challenge lies in the fact that vitreous and aqueous humor typically have low cellularity, and many cells get destroyed during collection, storage, and processing. Moreover, these specimens pose additional difficulties for molecular testing due to the high viscosity of vitreous humor and the low volume of both vitreous and aqueous humor. This study proposes a method for extracting cell-free DNA from vitreous and aqueous specimens. This approach complements the extraction of cellular DNA or allows the cellular component of these specimens to be utilized for other diagnostic methods, including cytology and flow cytometry.
Topics: Humans; Vitreous Body; Retinal Neoplasms; Cell-Free Nucleic Acids; Aqueous Humor; Biomarkers, Tumor; Eye Neoplasms; Lymphoma; DNA
PubMed: 38284545
DOI: 10.3791/65708 -
Ophthalmology. Retina Jan 2024Vitreoretinal lymphoma is a malignancy with high mortality. Incidence is rare, and there is a lack of medical evidence to direct management. This work describes... (Observational Study)
Observational Study
PURPOSE
Vitreoretinal lymphoma is a malignancy with high mortality. Incidence is rare, and there is a lack of medical evidence to direct management. This work describes presentation, diagnostic testing, and first treatment approaches in a recently diagnosed and treated patient cohort.
DESIGN
Clinical registry-based observational study.
SUBJECTS
Forty-eight women and 32 men (age range, 32-91 years; median age, 64 years) diagnosed with vitreoretinal lymphoma.
METHODS
An international network of ophthalmologists reported clinical features and management of patients presenting with vitreoretinal lymphoma between January 1, 2020 and December 31, 2022 via an electronic platform.
MAIN OUTCOME MEASURES
Visual acuity at presentation (logarithm of the minimum angle of resolution [logMAR]); basis for diagnosis; first treatment.
RESULTS
Vitreoretinal lymphoma was bilateral at presentation in 65% of patients (n = 52) and an initial site of lymphoma in 78% (n = 62). Of 127 eyes with lymphoma at presentation, vitreous was involved in 89% (n = 113) and was the only involved eye tissue in 40% (n = 51), and retina was involved in 46% (n = 59) and was the only involved eye tissue in 9% (n = 11). Median logMAR visual acuity of the worse-seeing eye was 0.50. The lymphoma was diagnosed from ocular specimens in 80% of patients (64/80), usually vitreous (57/64 patients [89%]), and on other clinical information in 20% of patients (16/80). Cellular studies were performed on ocular specimens from 59 of 64 patients (92%), most often cytology. Tumor gene analysis was used in 21 of 64 patients (33%), and cytokine assays were used in 13 of 64 patients (20%). For 76 patients (95%), treatment was initiated within 6 months of diagnosis and included ocular (38/76 [48%]), extraocular (17/76 [21%]), and ocular plus extraocular (21/76 [26%]) approaches. Intravitreal methotrexate was the most common ocular treatment (83/87 eyes [95%]).
CONCLUSIONS
Using data collected from 80 patients diagnosed with vitreoretinal lymphoma since 2020, we show that visual impairment is common, and that management often involves diagnosis by cellular tests and treatment with intravitreal chemotherapy.
FINANCIAL DISCLOSURE(S)
Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
Topics: Male; Humans; Female; Middle Aged; Adult; Aged; Aged, 80 and over; Retinal Neoplasms; Vitreous Body; Eye Neoplasms; Lymphoma; Diagnostic Techniques and Procedures
PubMed: 37648063
DOI: 10.1016/j.oret.2023.08.012 -
Experimental Eye Research Apr 2024Extracellular vesicles (EVs) are released as highly stable lipid bilayer particles carrying proteins, lipids, glycans and miRNAs. The contents of EVs vary based on the... (Review)
Review
Extracellular vesicles (EVs) are released as highly stable lipid bilayer particles carrying proteins, lipids, glycans and miRNAs. The contents of EVs vary based on the cellular origin, biogenesis route and the functional state of the cell suggesting certain diseased conditions. A growing body of evidence show that EVs carry important molecules implicated in the development and progression of ophthalmic diseases. EVs associated with ophthalmic diseases are mainly carried by one of the three ocular biofluids which include tears, aqueous humor and vitreous humor. This review summarizes the list of EV derived biomarkers identified thus far in ocular fluids for ophthalmic disease diagnosis. Further, the methods used for sample collection, sample volume and the sample numbers used in these studies have been highlighted. Emphasis has been given to describe the EV isolation and the characterization methods used, EV size profiled and the EV concentrations analyzed by these studies, thus providing a roadmap for future EV biomarker studies in ocular fluids.
Topics: Extracellular Vesicles; Biomarkers; MicroRNAs; Proteins; Body Fluids
PubMed: 38401855
DOI: 10.1016/j.exer.2024.109831 -
Forensic Science International Sep 2023Traumatic brain injury (TBI) is one of the major causes of morbidity and mortality worldwide. The patients' and injuries' heterogeneity associated with TBI, alongside...
BACKGROUND
Traumatic brain injury (TBI) is one of the major causes of morbidity and mortality worldwide. The patients' and injuries' heterogeneity associated with TBI, alongside with its variable clinical manifestations, make it challenging to make diagnosis and predict prognosis. Therefore, the identification of reliable prognostic markers would be relevant both to support clinical decision-making and forensic evaluation of polytraumatic deaths and cases of medical malpractice. This pilot study aimed to evaluate some of the main biomarkers specific for brain damage in sTBI and mmTBI deaths in samples of vitreous humor (VH) in order to verify whether predictors of prognosis in TBI can be found in this matrix.
METHODS
VH were obtained from both eyes (right and left) of 30 cadavers (20 sTBI and 10 mmTBI) and analysed. These factors were evaluated: NSE (neuron-specific enolase), S100 calcium-binding protein (S100), glial fibrillary acidic protein (GFAP), Brain-derived neurotrophic factor (BDNF), Copeptin, Interleukin 6 (IL-6), Ferritin, Lactate dehydrogenase (LDH), C-Reactive Protein (CRP), Procalcitonin (PCT), Glucose and Neutrophil gelatinase-associated lipocalin (N-Gal).
RESULTS
Four of the analysed proteins (LDH, ferritin, S100 and NSE) proved to be particularly promising. In particular, logistic regression analysis found a good discriminatory power.
CONCLUSIONS
Given the peculiarity of the matrix and the poor standardization of the sampling, such promising results need to be furtherly investigated in serum before being implemented in the forensic practice.
Topics: Humans; Pilot Projects; Vitreous Body; S100 Calcium Binding Protein beta Subunit; Brain Injuries, Traumatic; Biomarkers; Glial Fibrillary Acidic Protein; Ferritins
PubMed: 37467521
DOI: 10.1016/j.forsciint.2023.111782 -
BMJ Open Ophthalmology Dec 2023The quality of biological fluid samples is vital for optimal preanalytical procedures and a requirement for effective translational biomarker research. This study aims...
PURPOSE
The quality of biological fluid samples is vital for optimal preanalytical procedures and a requirement for effective translational biomarker research. This study aims to determine the effects of storage duration and freeze-thawing on the levels of various cytokines in the human aqueous humour and vitreous samples.
METHODS AND ANALYSIS
Human ocular aqueous humour and vitreous samples were obtained from 25 eyes and stored at -80°C for analysis. All samples were assayed for 27 cytokine biomarker concentrations (pg/mL) using a multiplex assay. Four sample storage durations following sample collection were evaluated (1 week, 3 months, 9 months and 15 months). Additionally, samples underwent up to three freeze-thaw cycles within the study period.
RESULTS
Among the 27 cytokine biomarkers, concentrations of four cytokines (Interleukin (IL)-2, IL-10, IL-12 and platelet-derived growth factor-BB) were significantly decreased by storage duration at all time points, as early as 3 months following sample collection (range of 9%-37% decline between 1 week and 15 months, p<0.001). Freeze-thawing of up to three cycles did not significantly impact the cytokine biomarker concentrations in aqueous humour or vitreous. Separability of patient-specific cytokine biomarker profiles in the principal component analysis remained relatively the same over the 15 months of storage duration.
CONCLUSION
The findings from this study suggest that several intraocular cytokine biomarkers in human aqueous humour and vitreous samples may be susceptible to degradation with long-term storage, as early as 3 months after collection. The overall patient-specific cytokine biomarker profiles are more stable than concentrations of individual cytokines. Future studies should focus on developing guidelines for optimal and standardised sample handling methods to ensure correct research findings about intraocular biomarkers are translated into clinical practice.
Topics: Humans; Cytokines; Biomarkers; Specimen Handling; Aqueous Humor; Face
PubMed: 38081779
DOI: 10.1136/bmjophth-2023-001346