Review

Authors: Nawazish Shaikh, Ramamurthy Srishti, Aayesha Khanum...

Vitreous hemorrhage is associated with a myriad of conditions such as proliferative diabetic retinopathy, proliferative retinopathy following vascular occlusion and vasculitis, trauma, retinal breaks, and posterior vitreous detachment without retinal break. Multiple pathological mechanisms are associated with development of vitreous hemorrhage such as disruption of abnormal vessels, normal vessels, and extension of blood from an adjacent source. The diagnosis of vitreous hemorrhage requires a thorough history taking and clinical examination including investigations such as ultra-sonography, which help decide the appropriate time for intervention. The prognosis of vitreous hemorrhage depends on the underlying cause. Treatment options include observation, laser photo-coagulation, cryotherapy, intravitreal injections of anti-vascular endothelial growth factor, and surgery. Pars plana vitrectomy remains the cornerstone of management. Complications of vitreous hemorrhage include glaucoma (ghost cell glaucoma, hemosiderotic glaucoma), proliferative vitreoretinopathy, and hemosiderosis bulbi.

Topics: Humans; Vitreous Hemorrhage; Vitrectomy; Vitreous Detachment; Vitreoretinopathy, Proliferative; Diabetic Retinopathy; Glaucoma; Retinal Perforations

PubMed: 36588205
DOI: 10.4103/ijo.IJO_928_22

Authors: Hirokazu Sakaguchi, Daijiro Kabata, Susumu Sakimoto...

PURPOSE

To evaluate the relationship between full-thickness macular hole (FTMH) onset and perifoveal posterior vitreous detachment using OCT data.

DESIGN

Retrospective study.

PARTICIPANTS

A total of 742 patients with FTMH or impending macular hole (MH) in ≥ 1 eye, as determined by ophthalmoscopy and OCT.

METHODS

Macular holes were staged using OCT results. Patients with the posterior vitreous membrane clearly detected in the OCT images and vitreoretinal adhesion size ≤ 1500 μm-eyes with MH stages 1-3-were included in the study. The contralateral eyes were also included in the analyses if they showed the focal type of vitreomacular adhesion (VMA) (i.e., vitreoretinal adhesion ≤ 1500 μm). The distance between the posterior vitreous membrane and the surface of the retina was defined as the posterior vitreous separation height (PVSH). Using the OCT images, PVSHs of each eye in 4 directions (nasal, temporal, superior, and inferior) at 1 mm from the center of the MH or fovea were calculated.

MAIN OUTCOME MEASURES

The main outcome measures were PVSHs according to the MH stage and VMA, the relationship of the foveal inner tear with PVSH, and the likelihood of a foveal inner tear based on the direction.

RESULTS

The PVSH trends in each of the 4 directions were as follows: VMA < MH stage 1 = MH stage 2 < MH stage 3. Initial MH stage 2 (onset of FTMH) was defined as the presence of a gap in only 1 of the 4 directions from the center of the MH. With increased PVSH, the likelihood of a gap increased ( = 0.002), and a temporal gap was more likely to occur than a nasal gap ( = 0.002).

CONCLUSIONS

At FTMH onset, a foveal inner tear likely appears on the temporal side or the side showing a high PVSH value.

FINANCIAL DISCLOSURES

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

PubMed: 37409190
DOI: 10.1016/j.xops.2023.100339

Authors: Janarthanam Jothi Balaji, Rajiv Raman, Vasudevan Lakshminarayanan...

BACKGROUND

Posterior vitreous detachment (PVD) can result in serious pathologic events at the vitreoretinal interface. This study aims to assess the relationship between PVD, macular thickness (MT), and the foveal avascular zone (FAZ) in myopic eyes.

METHODS

This retrospective study evaluated 63 myopic subjects' data who were examined between January 1 and June 30, 2019. The myopes were grouped on a severity scale, namely mild, moderate, high, and very high using their spherical equivalent (SE). The PVD classification was based on OCT images. The status of the PVD and MT were evaluated with the Macular Cube 200×200 images, the FAZ with an OCTA Angioplex, and the dimensions were calculated using a customized algorithm.

RESULTS

The study population (114 eyes) had a median (range) age was 26.00 (22.00-28.00) years and the females constituted 62.3% of the dataset. In this population, 10 eyes had no PVD in any quadrant, and 73 eyes had incomplete PVD in all four quadrants. The inferior quadrant had the maximum rate of PVD occurrences and the nasal quadrant had the least number of occurrences. High myopic eyes exhibited significantly increased low foveal volume (p = <0.01). The inferior part of the para- and perimacular area showed a significant thinning in very high myopic eyes (p = <0.050). The very high myopic eyes showed a significant alteration of FAZ's circularity index (p = 0.002).

CONCLUSION

In high and very high myopic eyes, an increasing trend of partial PVD is seen, most commonly in the inferior quadrant. A significant alteration in foveal volume and circularity index of the FAZ is seen in high and very high myopic eyes.

PubMed: 35256841
DOI: 10.2147/OPTH.S349531

Authors: Gregory S Fincham, Sean James, Carl Spickett...

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

Authors: Stewart R Lake, Murk J Bottema, Keryn A Williams...

INTRODUCTION

Retinal detachment is a sight-threatening emergency, with more than half of those affected suffering permanent visual impairment. A diagnostic test to identify eyes at risk before vision is threatened would enable exploration of prophylactic treatment. This report presents the use of irregularities in retinal shape, quantified from optical coherence tomography (OCT) images, as a biomarker for retinal detachment.

METHODS

OCT images were taken from posterior and mid-peripheral retina of 264 individuals [97 after a posterior vitreous detachment (PVD), 99 after vitrectomy for retinal detachment and 68 after laser for a retinal tear]. Diagnoses were taken from history, examination and OCT. Retinal irregularity was quantified in the frequency domain, and the distribution of irregularity across the regions of the eye was explored to identify features exhibiting the greatest difference between retinal detachment and PVD eyes. Two of these features plus axial length were used to train a quadratic discriminant analysis classifier. Classifier performance was assessed by its sensitivity and specificity in identifying retinal detachment eyes and visualised with a receiver operating characteristic (ROC) curve.

RESULTS

Validation set specificity was 84% (44/52 PVD eyes correctly labelled) and sensitivity 35% (23/64 retinal detachment eyes identified, p = 0.02). Area under the ROC curve was 0.75 (95% confidence intervals 0.58-0.85). Retinal detachment eyes were significantly more irregular than PVD eyes in the superior retina (0.70 mm versus 0.49 mm, p < 0.05) and supero-temporal retina (1.12 mm versus 0.80 mm, p < 0.05). Lower sensitivity (16/68, 24%) was seen for eyes with a retinal tear without detachment, that were intermediate in size between retinal detachment and PVD eyes. Axial length on its own was a poor classifier. Neither irregularity nor classification were affected by surgery for retinal detachment or the development of PVD.

CONCLUSIONS

The classifier identified 1/3 of retinal detachment eyes in this sample. In future work, these features can be evaluated as a test for retinal detachment prior to PVD.

PubMed: 36271185
DOI: 10.1007/s40123-022-00597-6

Authors: Olta Gishti, Ronald van den Nieuwenhof, Jennifer Verhoekx...

Flashes and floaters are the hallmark symptoms of a posterior vitreous detachment (PVD) which itself is related to an increased risk of the development of retinal tears, retinal detachment and vitreous haemorrhage. The aim of this study is to assess the associations between different symptoms related to PVD and the risk of developing retinal tears. A systematic review of articles written in English, using MEDLINE, Embase (via Embase.com) and the Cochrane Controlled Trials Register (1996-2017) was conducted. Search terms included five elements: PVD, retinal tears, retinal detachment, floaters and flashes. Independent extraction of articles was conducted by two authors using predefined data fields, including study quality indicators. Thirteen studies fulfilled the selection criteria. Analysis of pooled data revealed that presence of isolated flashes was associated with the development of retinal tears in 5.3% of symptomatic eyes [mean 2.9 eyes; 95% CI (2.1, 5.7)].Conversely, floaters alone had a stronger association with retinal tears (16.5% of eyes), as compared to flashes. The association to retinal tears was even greater for those patients reporting both flashes and floaters [mean 17.8 eyes (20.0%); 95% CI (17.4, 18.1)]. Retinal and/or vitreous haemorrhage was also associated with the presence and later development of retinal tears [mean 12.5 eyes (30.0%); 95% CI (11.7, 13.9)]. Patients with more than 10 floaters or a cloud in their vision had a high risk of developing retinal tears (OR19.8, p-value 0.032). In the setting of a PVD, the onset of flashes and floaters, and the presence of retinal and/or vitreous haemorrhage are risk factors for the development of retinal tears. The association is greater when both symptoms are present, and even greater when the patient reports more than 10 floaters, a curtain or a cloud and/or there is a positive finding of a vitreous or retinal haemorrhage. This study supports the necessity of an immediate examination of patients presenting with symptoms related to a PVD, and a follow-up examination might be prudent in a subgroup of these patients.

Topics: Fluorescein Angiography; Fundus Oculi; Global Health; Humans; Incidence; Retina; Retinal Perforations; Risk Assessment; Risk Factors; Vitreous Body; Vitreous Detachment

PubMed: 30632695
DOI: 10.1111/aos.14012

Review

Authors: Mel Maranian, Martin Snead

Retinal detachment (RD) is one of the most common, sight-threatening ocular conditions requiring emergency intervention. Posterior vitreous detachment (PVD) occurs in the majority of an aging population whereby the vitreous body separates from the retina. It is well established that PVD is the common precursor to the most common forms of RD; however, it remains unknown why in most individuals PVD will cause no/few complications (physiological PVD) but in a small percentage will cause retinal tears and detachment (pathological PVD). Despite over 100 years of scientific research, the anatomical definitions of PVD and its pathogenesis remain controversial. Recent research has identified a novel cell population (laminocyte), present at significantly higher numbers in pathological PVD when compared to physiological PVD. We review and summarise the seven distinct clinical sub-groups of retinal breaks and focus on the role of the laminocyte in those secondary to PVD and the transcriptomic profile of this unique cell. Provisional whole transcriptome analysis using bulk RNA-Seq shows marked differentially expressed genes when comparing physiological PVD with PVD associated with RD. The limitations of bulk RNA-Seq are considered and the potential to address these using spatial transcriptomics are discussed. Understanding the pathogenesis of PVD-related retinal tears will provide a baseline for the development of novel therapeutic targets and prophylactic treatments.

Topics: Humans; Aged; Retinal Detachment; Retinal Perforations; Transcriptome; Pathology, Molecular; Vitreous Detachment

PubMed: 36292771
DOI: 10.3390/genes13101885

Authors: Taku Toyama, Hisashi Kawai, Tomoyasu Shiraya...

PURPOSE

To investigate the association between different stages of posterior vitreous detachment (PVD) and macular microvasculature in the elderly.

METHODS

Swept-source optical coherence tomography (OCT), OCT angiography, and color fundus images of 490 eyes without retinal pathologies of 322 participants aged ≥65 years were evaluated. PVD was classified using enhanced vitreous visualization mode as no apparent PVD (stage 0/1), vitreous adhesions at the fovea and optic disc (stage 2), adhesion at the optic disc (stage 3), or complete PVD (stage 4). Microvascular parameters, including foveal avascular zone (FAZ) and vessel density (VD), were analyzed for their associations with complete PVD. Additionally, the association between PVD and central retinal thickness (CRT) was also addressed.

RESULTS

Overall, 80, 31, 31, and 349 eyes were categorized into stages 0/1, 2, 3, and 4, respectively. Using multivariate mixed-effects model, the mean superficial FAZ area was smaller in stage 4 compared with stages 0-3 (0.29 vs. 0.32 mm2; P = 0.014), and the mean superficial VD was lower in stage 4 compared with stages 0-3 (34.96% vs. 35.24%; P = 0.0089). However, PVD was not significantly associated with deep macular microvascular parameters or CRT.

CONCLUSIONS

Complete PVD was associated with smaller FAZ area and lower VD in superficial macular microvasculature, while it was not associated with central retinal thickness.

Topics: Aged; Cross-Sectional Studies; Eye; Female; Fluorescein Angiography; Humans; Macula Lutea; Macular Degeneration; Male; Microvessels; Middle Aged; Retina; Severity of Illness Index; Tomography, Optical Coherence; Vitreous Detachment

PubMed: 32267887
DOI: 10.1371/journal.pone.0231351