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BMJ Open Ophthalmology Nov 2023To explore the current research about the role of optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) in dysthyroid optic neuropathy... (Meta-Analysis)
Meta-Analysis
PURPOSE
To explore the current research about the role of optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) in dysthyroid optic neuropathy (DON).
METHODS
Studies in the literature that focused on OCT, OCTA and DON were retrieved by searching PubMed, EMBASE, Cochrane databases and Clinical Trial before 20 June 2023. The methodological quality was assessed using the Newcastle-Ottawa scale. The quantitative calculation was performed using Review Manager V.5.3.
RESULTS
Twelve studies met the eligibility criteria and were included. DON group presented lower macular ganglion cell complex in the overall, superior and inferior hemifields compared with the non-DON group. Furthermore, the ganglion cell layer and inner plexiform layer in DON group was thinner in contrast to the non-DON group. The optic nerve head vessel density was lower in the DON group than that in the non-DON group. A reduction of radial peripapillary capillary vessel density could be seen in the DON group than the non-DON group in overall, inside disc, peripapillary, superior-hemifield, temporal and nasal. Besides, the macular superficial retinal capillary layer of non-DON and DON is lower than the healthy control group.
CONCLUSIONS
This study supported the potential value of OCT and OCTA metrics as novel biomarkers of DON. Ophthalmologists should comprehensively consider the retinal structure and microvasculature in dealing with DON.
ETHICS AND DISSEMINATION
This systematic review included data from published literature and was exempt from ethics approval. Results would be disseminated through peer-reviewed publication and presented at academic conferences engaging clinicians.
PROSPERO REGISTRATION NUMBER
CRD42023414907.
Topics: Humans; Tomography, Optical Coherence; Optic Disk; Angiography; Retinal Ganglion Cells; Optic Nerve Diseases
PubMed: 37996119
DOI: 10.1136/bmjophth-2023-001379 -
Experimental Eye Research Sep 2023Animal models of choroidal neovascularization (CNV) are extensively used in translational studies of CNV formation and to evaluate angiostatic treatment strategies.... (Review)
Review
Animal models of choroidal neovascularization (CNV) are extensively used in translational studies of CNV formation and to evaluate angiostatic treatment strategies. However, the current paucity of large animal models compared with rodent models constitutes a knowledge gap regarding the clinical translation of findings. Ocular anatomical and physiological similarities to humans suggest the pig as a relevant model animal. Thus, a systematic survey of porcine CNV models was performed to identify pertinent model parameters and suggest avenues for model standardization and optimization. A systematic search was performed in PubMed and EMBASE on November 28, 2022 for porcine models of CNV. Following inclusion by two investigators, data from the articles were extracted according to a predefined protocol. A total of 14 articles, representing 19 independent porcine CNV models were included. The included models were almost equally divided between laser-induced (53%) and surgically-induced (47%) models. Different specified breeds of domestic pigs (71%) were most commonly used in the studies. All studies used normal animals. Female pigs were reported used in 43% of the studies, while 43% did not report on sex of the animals. Younger pigs were typically used. The surgical models reported consistent CNV induction following mechanical Bruch's membrane rupture. The laser models used variants of the infrared diode laser (40%) or the frequency-doubled Nd:YAG laser (50%). Both lasers enabled successful CNV induction with reported induction rates ranging from 60 to 100%. Collateral damage to the neuroretina was reported for the infrared diode laser. CNV evaluation varied across studies with fluorescein angiography (50%) as the most used in vivo method and retinal sections (71%) as the most used ex vivo method. In interventional studies, quantification of lesions was in general performed between 7 and 14 days. The field of porcine CNV models is relatively small and heterogeneous and almost equally divided between surgically-induced and laser-induced models. Both methods have allowed successful modeling of CNV formation with induction rates comparable to those of non-human primates. However, the field would benefit from standardization of model parameters and reporting. This includes laser parameters and validation of CNV formation as well as methods of CNV evaluation and statistical analysis.
Topics: Female; Humans; Swine; Animals; Disease Models, Animal; Choroidal Neovascularization; Retina; Bruch Membrane; Fluorescein Angiography
PubMed: 37474015
DOI: 10.1016/j.exer.2023.109590 -
Frontiers in Medicine 2022To date, various treatments for cystoid macular edema (CME) in retinitis pigmentosa (RP) have been reported. We performed a systematic review and meta-analysis to...
BACKGROUND
To date, various treatments for cystoid macular edema (CME) in retinitis pigmentosa (RP) have been reported. We performed a systematic review and meta-analysis to evaluate the efficacy and safety of current treatments for RP-CME.
METHODS
PubMed, Embase and the Cochrane library were searched from inception to August 2021. ClinicalTrials.gov, WHO ICTRP and ISRCTN were also searched for relevant studies. Only studies published in English were included. The RoB 2 tool was used to evaluate the risk of bias of randomized controlled trials (RCTs), and the MINORS scale was used to assess the methodological quality of non-RCTs. Review manager (Revman) was used to pool the data. The primary outcomes included the change of central macular thickness (CMT) and best-corrected visual acuity (BCVA) from baseline. The secondary outcomes included fluorescein angiography (FA) leakage, rebound of CME and adverse effects.
RESULTS
Thirty-two studies were included in the current systematic review and 7 studies were used for meta-analysis. Treatments for RP-CME included oral and topical carbonic anhydrase inhibitors (CAIs), systematic and local steroids, anti-VEGF therapy, NSAIDS, grid LASER photocoagulation, subliminal micropulse LASER, vitrectomy, lutein supplement and oral minocycline. CAIs and local steroids were proved to be effective in reducing CMT. The effects of anti-VEGF reagents varied among studies. Regarding other treatments, only one study for each method fitted the inclusion criteria, so the evidence was very limited.
CONCLUSION
Topical CAIs, oral CAIs and local steroids are effective in treating RP-CME. However, due to the overall inferior design and small patient number of the included studies, the quality of evidence was poor. Systematic steroids, LASER, NSAIDS and vitrectomy may also be effective, nevertheless, considering the limited number of studies, no conclusion could be drawn regarding these treatments. More well-designed and conducted studies are needed in this field.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021273979, identifier CRD42021273979.
PubMed: 35652079
DOI: 10.3389/fmed.2022.895208 -
Graefe's Archive For Clinical and... Jan 2024The association of obstructive sleep apnea (OSA) with development of eye diseases is unclear. This current systematic review and meta-analysis attempts to summarize and... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The association of obstructive sleep apnea (OSA) with development of eye diseases is unclear. This current systematic review and meta-analysis attempts to summarize and analyze associations between OSA and ocular disorders in the literature.
METHODS
PubMed, EMBASE, Google Scholar, Web Of Science, and Scopus databases were searched from 1901 to July 2022 in accordance with the Preferred Reporting in Systematic Review & Meta-Analysis (PRISMA). Our primary outcome assessed the association between OSA and the odds of developing floppy eyelid syndrome (FES), glaucoma, non-arteritic anterior ischemic optic neuropathy (NAION), retinal vein occlusion (RVO), keratoconus (KC), idiopathic intracranial hypertension (IIH), age-related macular degeneration (AMD), and central serous chorioretinopathy (CSR) through odds ratio calculated at the 95% confidence interval.
RESULTS
Forty-nine studies were included for systematic review and meta-analysis. The pooled OR estimate was highest for NAION [3.98 (95% CI 2.38, 6.66)], followed by FES [3.68 (95% CI 2.18, 6.20)], RVO [2.71(95% CI 1.83, 4.00)], CSR [2.28 (95% CI 0.65, 7.97)], KC [1.87 (95% CI 1.16, 2.99)], glaucoma [1.49 (95% CI 1.16, 1.91)], IIH [1.29 (95% CI 0.33, 5.01)], and AMD [0.92 [95% CI 0.24, 3.58] All observed associations were significant (p < 0.001) aside from IIH and AMD.
CONCLUSION
OSA is significantly associated with NAION, FES, RVO, CSR, KC, and glaucoma. Clinicians should be informed of these associations so early recognition, diagnosis, and treatment of eye disorders can be addressed in at-risk groups, and early referral to ophthalmic services is made to prevent vision disturbances. Similarly, ophthalmologists seeing patients with any of these conditions should consider screening and referring patients for assessment of possible OSA.
Topics: Humans; Eyelid Diseases; Glaucoma; Keratoconus; Optic Neuropathy, Ischemic; Retinal Vein Occlusion; Sleep Apnea, Obstructive
PubMed: 37227479
DOI: 10.1007/s00417-023-06103-3 -
Biology Direct Oct 2023The social impact of glaucoma is worth of note: primary open-angle glaucoma (POAG) is one of the leading causes of irreversible blindness worldwide, affecting some 68.56... (Meta-Analysis)
Meta-Analysis Review
The social impact of glaucoma is worth of note: primary open-angle glaucoma (POAG) is one of the leading causes of irreversible blindness worldwide, affecting some 68.56 million people with overall prevalence of 2.4%. Since one of the main risk factors for the development of POAG is the increase of intraocular pressure (IOP) causing retinal ganglion cells death, the medical treatment of POAG consists in the use of drugs endowed with neuroprotective effect and able to reduce IOP. These drugs include beta-blockers, prostaglandin analogues, carbonic anhydrase inhibitors, alpha or cholinergic agonists and rho kinase inhibitors. However, not all the patients respond to the same extent to the therapy in terms of efficacy and safety. Genetics and genome wide association studies have highlighted the occurrence of mutations and polymorphisms influencing the predisposition to develop POAG and its phenotype, as well as affecting the response to pharmacological treatment. The present systematic review and meta-analysis aims at identifying genetic variants and at verifying whether these can influence the responsiveness of patients to therapy for efficacy and safety. It follows the most updated Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020 recommendations. The literature search was conducted consulting the most relevant scientific databases, i.e. PubMed/MEDLINE, Scopus, Web of Science and Public Health Genomics and Precision Health Knowledge Base up to June 14th, 2023. The search retrieved 1026 total records, among which eight met the eligibility criteria for inclusion in the analysis. The results demonstrated that the most investigated pharmacogenetic associations concern latanoprost and timolol, and that efficacy was studied more in depth than safety. Moreover, the heterogeneity of design and paucity of studies prompt further investigation in randomized clinical trials. In fact, adequately powered and designed pharmacogenetic association studies are needed to provide body of evidence with good certainty for a more appropriate use of medical therapy in POAG.PROSPERO registration: CRD42023434867.
Topics: Humans; Glaucoma, Open-Angle; Antihypertensive Agents; Genome-Wide Association Study; Timolol; Genotype
PubMed: 37833756
DOI: 10.1186/s13062-023-00423-4 -
Translational Vision Science &... Nov 2023This systematic review evaluates the safety and efficacy of ocular gene therapy using adeno-associated virus (AAV). (Meta-Analysis)
Meta-Analysis
PURPOSE
This systematic review evaluates the safety and efficacy of ocular gene therapy using adeno-associated virus (AAV).
METHODS
MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov were searched systematically for controlled or non-controlled interventional gene therapy studies using key words related to retinal diseases, gene therapy, and AAV vectors. The primary outcome measure was safety, based on ocular severe adverse events (SAEs). Secondary outcome measures evaluated efficacy of the therapy based on best corrected visual acuity (BCVA) and improvements in visual sensitivity and systemic involvement following ocular delivery. Pooling was done using a DerSimonian Laird random effects model. Risk of bias was assessed using the Cochrane Risk of Bias Tool, version 1.
RESULTS
Our search identified 3548 records. Of these, 80 publications met eligibility criteria, representing 28 registered clinical trials and 5 postmarket surveillance studies involving AAV gene therapy for Leber congenital amaurosis (LCA), choroideremia, Leber hereditary optic neuropathy (LHON), age-related macular degeneration (AMD), retinitis pigmentosa (RP), X-linked retinoschisis, and achromatopsia. Overall, AAV therapy vectors were associated with a cumulative incidence of at least one SAE of 8% (95% confidence intervals [CIs] of 5% to 12%). SAEs were often associated with the surgical procedure rather than the therapeutic vector itself. Poor or inconsistent reporting of adverse events (AEs) were a limitation for the meta-analysis. The proportion of patients with any improvement in BCVA and visual sensitivity was 41% (95% CIs of 31% to 51%) and 51% (95% CIs of 31% to 70%), respectively. Systemic immune involvement was associated with a cumulative incidence of 31% (95% CI = 21% to 42%).
CONCLUSIONS
AAV gene therapy vectors appear to be safe but the surgical procedure required to deliver them is associated with some risk. The large variability in efficacy can be attributed to the small number of patients treated, the heterogeneity of the population and the variability in dosage, volume, and follow-up.
TRANSLATIONAL RELEVANCE
This systematic review will help to inform and guide future clinical trials.
Topics: Humans; Retinal Degeneration; Dependovirus; Macular Degeneration; Retinitis Pigmentosa; Genetic Therapy
PubMed: 37982768
DOI: 10.1167/tvst.12.11.24 -
The Cochrane Database of Systematic... Jan 2023Uveitis is a term used to describe a group of intraocular inflammatory diseases. Uveitis is the fifth most common cause of vision loss in high-income countries, with the... (Review)
Review
BACKGROUND
Uveitis is a term used to describe a group of intraocular inflammatory diseases. Uveitis is the fifth most common cause of vision loss in high-income countries, with the highest incidence of disease in the working-age population. Corticosteroids are the mainstay of treatment for all subtypes of non-infectious uveitis. They can be administered orally, topically with drops, by periocular (around the eye) or intravitreal (inside the eye) injection, or by surgical implantation.
OBJECTIVES
To determine the efficacy and safety of steroid implants in people with chronic non-infectious posterior uveitis, intermediate uveitis, and panuveitis.
SEARCH METHODS
We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register), MEDLINE Ovid, Embase, PubMed, LILACS, and three trials registries to November 2021. SELECTION CRITERIA: We included randomized controlled trials comparing either fluocinolone acetonide (FA) or dexamethasone (DEX) intravitreal implants with standard-of-care therapy or sham procedures, with at least six months of follow-up after treatment. We included studies that enrolled participants of all ages, who had chronic non-infectious posterior uveitis, intermediate uveitis, or panuveitis with vision that was better than hand-motion.
DATA COLLECTION AND ANALYSIS
We applied standard Cochrane methodology.
MAIN RESULTS
We included data from four trials (683 participants, 907 eyes) that compared corticosteroid implants with either sham or standard-of-care therapy. Study characteristics and risk of bias Of the two trials that compared corticosteroid implants with sham procedure, one examined a 0.18 mg FA implant, and the other, a 0.7 mg DEX implant. The other two trials compared a 0.59 mg FA implant with standard-of-care therapy, which included systemic corticosteroids and immunosuppressive medications, if needed. We assessed the four trials to be at either low risk, or with some concerns of risk of bias across all domains. Findings Using sham procedure as control, combined results at the six-month primary time point suggested that corticosteroid implants may decrease the risk of uveitis recurrence by 60% (relative risk [RR] 0.40, 95% confidence interval [CI] 0.30 to 0.54; 2 trials, 282 participants; low-certainty evidence); and lead to a greater improvement in best-corrected visual acuity (BCVA; mean difference [MD] 0.22 logMAR, 95% CI 0.13 to 0.31; 1 trial, 153 participants; low-certainty evidence). Evidence based on a single-study report (146 participants) suggested that steroid implants may have no effects on visual functioning quality of life, measured on the National Eye Institute 25-Item Visual Function Questionnaire (MD 2.85, 95%CI -3.64 to 9.34; 1 trial, 146 participants; moderate-certainty evidence). Using standard-of care therapy as control, combined estimates at the 24-month primary time point suggested that corticosteroid implants were likely to decrease the risk of recurrence of uveitis by 54% (RR 0.46, 95% CI 0.35 to 0.60; 2 trials, 619 eyes). Combined estimates at 24 months also suggested that steroid implants may have little to no effects on BCVA (MD 0.05 logMAR, 95% CI -0.02 to 0.12; 2 trials, 619 eyes; low-certainty evidence). Evidence based on a single-study report (232 participants) suggested that steroid implants may have minimal clinical effects on visual functioning (MD 4.64, 95% CI 0.13 to 9.15; 1 trial, 232 participants; moderate-certainty evidence); physical functioning (SF-36 physical subscale MD 2.95, 95% CI 0.55 to 5.35; 1 trial, 232 participants; moderate-certainty evidence); or mental health (SF-36 mental subscale MD 3.65, 95% CI 0.52 to 6.78; 1 trial, 232 participants; moderate-certainty evidence); but not on EuroQoL (MD 6.17, 95% CI 1.87 to 10.47; 1 trial, 232 participants; moderate-certainty evidence); or EuroQoL-5D scale (MD 0.02, 95% CI -0.04 to 0.08; 1 trial, 232 participants; moderate-certainty evidence). Adverse effects Compared with sham procedures, corticosteroid implants may slightly increase the risk of cataract formation (RR 2.69, 95% CI 1.17 to 6.18; 1 trial, 90 eyes; low-certainty evidence), but not the risk of cataract progression (RR 2.00, 95% CI 0.65 to 6.12; 1 trial, 117 eyes; low-certainty evidence); or the need for surgery (RR 2.98, 95% CI 0.82 to 10.81; 1 trial, 180 eyes; low-certainty evidence), during up to 12 months of follow-up. These implants may increase the risk of elevated intraocular pressure ([IOP] RR 2.81, 95% CI 1.42 to 5.56; 2 trials, 282 participants; moderate-certainty evidence); and the need for IOP-lowering eyedrops (RR 1.85, 95% CI 1.05 to 3.25; 2 trials, 282 participants; moderate-certainty evidence); but not the need for IOP-lowering surgery (RR 0.72, 95% CI 0.13 to 4.17; 2 trials, 282 participants; moderate-certainty evidence). Evidence comparing the 0.59 mg FA implant with standard-of-care suggested that the implant may increase the risk of cataract progression (RR 2.71, 95% CI 2.06 to 3.56; 2 trials, 210 eyes; low-certainty evidence); and the need for surgery (RR 2.98, 95% CI 2.33 to 3.79; 2 trials, 371 eyes; low-certainty evidence); along with the risk of elevated IOP (RR 3.64, 95% CI 2.71 to 4.87; 2 trials, 605 eyes; moderate-certainty evidence); and the need for medical (RR 3.04, 95% CI 2.36 to 3.91; 2 trials, 544 eyes; moderate-certainty evidence); or surgical interventions (RR 5.43, 95% CI 3.12 to 9.45; 2 trials, 599 eyes; moderate-certainty evidence). In either comparison, these implants did not increase the risk for endophthalmitis, retinal tear, or retinal detachment (moderate-certainty evidence). AUTHORS' CONCLUSIONS: Our confidence is limited that local corticosteroid implants are superior to sham therapy or standard-of-care therapy in reducing the risk of uveitis recurrence. We demonstrated different effectiveness on BCVA relative to comparators in people with non-infectious uveitis. Nevertheless, the evidence suggests that these implants may increase the risk of cataract progression and IOP elevation, which will require interventions over time. To better understand the efficacy and safety profiles of corticosteroid implants, we need future trials that examine implants of different doses, used for different durations. The trials should measure core standard outcomes that are universally defined, and measured at comparable follow-up time points.
Topics: Humans; Adrenal Cortex Hormones; Cataract; Glaucoma; Panuveitis; Quality of Life; Steroids; Uveitis; Uveitis, Intermediate; Randomized Controlled Trials as Topic
PubMed: 36645716
DOI: 10.1002/14651858.CD010469.pub3 -
Journal of Clinical Medicine Sep 2022(1) Background: We aimed to systematically review the current literature to evaluate if in patients with postoperative endophthalmitis treated with pars plana... (Review)
Review
(1) Background: We aimed to systematically review the current literature to evaluate if in patients with postoperative endophthalmitis treated with pars plana vitrectomy, silicone oil tamponade could provide a useful contribution to the control and eradication of infection and if it could influence anatomical recovery and functional outcome. (2) Randomized controlled trials, cross-sectional studies, case series, and case reports published in the English language in peer-reviewed journals were included. No restriction was placed based on the study location. We used medical subject headings (MeSH) and text words. We searched MEDLINE (OVID and PubMed), Google Scholar, ISI Web of Science (Thom-on-Reuters), and the Cochrane Library (Wiley) from January 1995 to the present. To ensure literature saturation, we scanned the reference lists of included studies or relevant reviews identified through the search. Risk of Bias was assessed using the Newcastle-Ottawa scale for longitudinal studies and Cochrane risk-of-bias tool for randomized trials. (3) Results: abstracts of 75 articles were selected for full-text reading; after full-text reading, 44 articles were taken into consideration in the systematic review. 5 out of 7 in vitro experimental studies demonstrated antimicrobial activity against different species of bacteria and fungi. The use of SO as endotamponade associated with PPV led to better visual acuity and a lower rate of retinal detachment and the need for additional surgery. (4) Conclusions: Silicone oil reduces the risk of postoperative retinal detachment, especially in case of undetected retinal breaks, produces compartmentalization of the eye, may lead to early visual recovery, allows laser photocoagulation, prevents severe postoperative hypotony and has antimicrobic activity due to an inhibitory effect for several species of pathogens. Concerns regarding possible toxic effects on the retina and optic disc, compartmentalization and impaired washout of pathogen toxins have been reported. It may also influence intravitreal antibiotic distribution and clearance.
PubMed: 36143089
DOI: 10.3390/jcm11185445 -
Translational Vision Science &... Jul 2023The purpose of this study was to perform a systematic review and meta-analysis to synthesize evidence from studies using deep learning (DL) to predict cardiovascular... (Meta-Analysis)
Meta-Analysis
PURPOSE
The purpose of this study was to perform a systematic review and meta-analysis to synthesize evidence from studies using deep learning (DL) to predict cardiovascular disease (CVD) risk from retinal images.
METHODS
A systematic literature search was performed in MEDLINE, Scopus, and Web of Science up to June 2022. We extracted data pertaining to predicted outcomes, model development, and validation and model performance metrics. Included studies were graded using the Quality Assessment of Diagnostic Accuracies Studies 2 tool. Model performance was pooled across eligible studies using a random-effects meta-analysis model.
RESULTS
A total of 26 studies were included in the analysis. There were 42 CVD risk-related outcomes predicted from retinal images were identified, including 33 CVD risk factors, 4 cardiac imaging biomarkers, 2 CVD risk scores, the presence of CVD, and incident CVD. Three studies that aimed to predict the development of future CVD events reported an area under the receiver operating curve (AUROC) between 0.68 and 0.81. Models that used retinal images as input data had a pooled mean absolute error of 3.19 years (95% confidence interval [CI] = 2.95-3.43) for age prediction; a pooled AUROC of 0.96 (95% CI = 0.95-0.97) for gender classification; a pooled AUROC of 0.80 (95% CI = 0.73-0.86) for diabetes detection; and a pooled AUROC of 0.86 (95% CI = 0.81-0.92) for the detection of chronic kidney disease. We observed a high level of heterogeneity and variation in study designs.
CONCLUSIONS
Although DL models appear to have reasonably good performance when it comes to predicting CVD risk, further work is necessary to evaluate the real-world applicability and predictive accuracy.
TRANSLATIONAL RELEVANCE
DL-based CVD risk assessment from retinal images holds great promise to be translated to clinical practice as a novel approach for CVD risk assessment, given its simple, quick, and noninvasive nature.
Topics: Humans; Cardiovascular Diseases; Deep Learning
PubMed: 37440249
DOI: 10.1167/tvst.12.7.14 -
The Cochrane Database of Systematic... Sep 2021Assisted vaginal births are carried out to expedite birth for the benefit of mothers and babies but are sometimes associated with significant morbidity for both.... (Review)
Review
BACKGROUND
Assisted vaginal births are carried out to expedite birth for the benefit of mothers and babies but are sometimes associated with significant morbidity for both. Various instruments are available, broadly divided into forceps and vacuum cups, and choice may be influenced by clinical circumstances, operator preference, experience and availability. OBJECTIVES: To evaluate the different instruments in terms of success in achieving a vaginal birth, and the risk of morbidity for mother and baby.
SEARCH METHODS
We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (14 May 2021), and reference lists of retrieved studies.
SELECTION CRITERIA
We selected randomised controlled trials of assisted vaginal birth using different instruments. The review did not include quasi-randomised trials, cluster-randomised trials or cross-over designs. The review included trials for which abstracts alone were available as long as there was sufficient information to assess eligibility. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. We used the GRADE approach to assess the certainty of evidence. The main outcomes assessed included failed delivery with allocated instrument, any maternal trauma, third- and fourth-degree tears, postpartum haemorrhage, any neonatal trauma, low Apgar and low umbilical artery pH. MAIN RESULTS: We included 31 studies involving a total of 5754 women. Risk of bias criteria were largely assessed as 'unclear', due to a lack of detail in trial reports. Blinding would have been challenging for all trials due to their inability to conceal the type of instrument used from either the woman or the operator, which is reflected in the risk of bias assessment. Any type of forceps versus any type of vacuum cup (12 studies, 3129 women) Forceps may be less likely to fail in achieving vaginal birth: risk ratio (RR) 0.58, 95% confidence interval (CI) 0.39 to 0.88; 11 studies, 3080 women; low certainty. 'Any maternal trauma' may be slightly more likely with forceps: odds ratio (OR) 1.53, 95% CI 0.98 to 2.40; 5 studies, 1356 women; low certainty; and third- or fourth-degree tears may also be more likely with forceps: RR 1.83, 95% CI 1.32 to 2.55; 9 studies, 2493 women; low certainty. There is no evidence of a difference in the incidence of postpartum haemorrhage (PPH) between the two groups: RR 1.71, 95% CI 0.59 to 4.95; 2 studies, 523 women; low certainty, because the evidence is very imprecise due to a very wide CI. More women in the forceps group reported requiring pain relief. There is probably no evidence of difference in rates of low Apgar: RR 0.83, 95% CI 0.46 to 1.51; 7 studies, 1644 women; moderate certainty; or low umbilical artery pH in the forceps group compared to any vacuum: RR 1.33, 95% CI 0.91 to 1.93; 2 studies, 789 women; low certainty; both of these outcomes are imprecise and have wide CIs that include both benefit and harm. There were also lower rates of fetal trauma with 'any forceps' (cephalhematoma, retinal haemorrhage and jaundice). The composite outcome of 'any neonatal trauma' was not reported. Low-cavity forceps versus any vacuum cup (2 studies, 218 women) We included two small studies with 218 participants in this comparison, but we judged most of the evidence as very low certainty, hence it was not feasible to make judgements on the difference in the rates of failed delivery, any maternal trauma or third- and fourth- degree tears. PPH and low umbilical artery pH were not reported. Soft vacuum cup versus any rigid cup (9 studies, 1148 women) Failed delivery may be more likely in the soft vacuum cup group: RR 1.62, 95% CI 1.21 to 2.17; 9 studies, 1148 women; low certainty. There may be no difference in the rates of 'any maternal trauma': OR 0.63, 95% CI 0.24 to 1.67; 2 studies, 348 women; low certainty, but the confidence interval is wide, indicating possible benefit or harm. There may be no difference in the rates of third- or fourth-degree tears: RR 0.93, 95% CI 0.35 to 2.44; 4 studies, 619 women; low certainty. There is probably no difference in the rates of PPH: RR 0.89, 95% CI 0.49 to 1.61; 5 studies, 737 women; moderate certainty between the soft and rigid cup groups. There may be little or no difference in the incidence of low Apgar scores: RR 0.82, 95% CI 0.49 to 1.37; 9 studies, 1148; low certainty; or low umbilical artery pH: RR 0.80, 95% CI 0.47 to 1.36; 1 study, 100 women; low certainty. Handheld vacuum versus any vacuum cup (4 studies, 968 women) There may be no difference in the rates of failures with allocated instrument: RR 1.35, 95% CI 0.81 to 2.25; 4 studies, 962 women; low certainty, any maternal trauma: OR 1.16, 95% CI 0.71 to 1.88; 2 studies; 394 women; low certainty, PPH: RR 0.31, 95% CI 0.03 to 2.92; 1 study, 164 women; low certainty, low umbilical artery pH: RR 1.06, 95% CI 0.71 to 1.59; 1 study, 164 women; low certainty, or low Apgar scores: RR 1.25, 95% CI 0.34 to 4.61; 3 studies, 784 women; low certainty) between the two groups. There is probably no difference in the rates of third- or fourth-degree tears between the 'handheld vacuum' and 'any vacuum cup' groups: RR 1.15, 95% CI 0.62 to 2.12; 4 studies, 962 women; moderate certainty.
AUTHORS' CONCLUSIONS
This review provides low-certainty evidence that forceps may be more likely to achieve vaginal birth and have lower rates of fetal trauma, but at a greater risk of perineal trauma and higher pain relief requirements compared with vacuum cups. There was low-certainty evidence that rigid vacuum cups may be more likely to achieve a vaginal birth than soft cups but with more fetal trauma, whilst handheld vacuum cups had similar success rates compared to other cups. There was no evidence of a difference in the rates of third- or fourth-degree tears or postpartum haemorrhages between types of cups, but wide confidence intervals around the estimates indicate further research is needed in this area.
Topics: Female; Humans; Infant; Infant, Newborn; Parturition; Postpartum Hemorrhage; Pregnancy
PubMed: 34559884
DOI: 10.1002/14651858.CD005455.pub3