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The purpose was to review the efficacy and safety of CCS in improving functional and anatomical outcomes and in preventing postoperative complications. This review is organized according to the timing of CCS administration: preoperative, intraoperative, and postoperative. No solid consensus exists on intraoperative and postoperative use of CCS to treat and prevent postoperative complications. However, a large randomized clinical trial including more than eyes suggested that oral prednisone after surgery decreases the rate of postoperative grade B PVR.

Keywords: rhegmatogenous retinal detachment; vitrectomy; scleral buckling; dexamethasone; triamcinolone; fluocinolone; corticosteroids 1. Introduction Rhegmatogenous retinal detachment RRD is a common retinal disease with an incidence of one in 10, people per year [1] that often causes visual field defects and moderate to severe visual J.

However, despite primary anatomic success, degeneration of the photoreceptors and post-operative complications, such as proliferative vitreoretinopathy PVR often occur as a result of inflammation, preventing complete functional recovery or causing RRD recurrence [3,4].

There is increasing evidence that in the presence of RRD, the activation of inflammatory processes occurs, in particular when it is associated with choroidal detachment [5,6]. The surgeries themselves, both scleral buckle SB and pars plana vitrectomy PPV , induces an inflammatory response as demonstrated by an increase of aqueous flare values, from day one up to three months post-operatively with the peak value observed at post-operative day seven [7].

Corticosteroid CCS drugs are able to modulate inflammation by binding intracellular receptors and regulating cytokine synthesis [8]. Several studies have already investigated the efficacy of CCS prior, during, and after surgery for RRD repair, administered in different formulations: topical, subconjunctival, subtenon ST , intravitreal IVT and systemic; however, there is no agreement about the most efficient formulation with the least side effects. Ando et al. Moreover, Bali et al.

Weijtens et al. Shen et al. A higher glucose level is another side effect of particular concern, especially in diabetic patients [20]. Ocular complications of corticosteroid use have been well reported after intravenous, oral, topical ocular and cutaneous , and injected sub-conjunctival, subtenon, and periocular corticosteroids. In particular, oral corticosteroid use can cause glaucoma and cataract development with a threshold dose-related pattern a mean value dosage of over 7.

Secondary ocular hypertension was also reported after subtenon and intravitreal TA injection 4. Methods 2. Search Methods for Identification of Studies Literature from the PubMed search engine was analyzed to find current evidence on CSS use in addition to surgery for the management of RRD with or without choroidal detachment; papers published from up to December were analyzed.

Articles in which steroids were used as a dye for vitreous, posterior hyaloid or internal limiting membrane, were excluded, as well as articles concerning the use of CCS in the management of postoperative complications such as cystoid macular edema. The reference lists of the analyzed articles were also considered as a potential source of information.

Data Collection The present review was structured in three sections based on the timing of CCS use in addition to surgery: preoperative, intraoperative, and postoperative. The following mean characteristics were analyzed for each article: 1 Study design: retrospective, prospective, comparative and non-comparative, randomized and non-randomized, single-center and multicenter and case report 2 Clinical outcomes: anatomical and functional 3 3Number of eyes studied 4 Primary treatment 5 Follow-up duration of the study 6 Main results 7 Side effects Two investigators VB and EO independently assessed the articles for compliance with the inclusion criteria concerning the selection of the papers to be analyzed and resolved disagreements through consensus.

Results A total of articles were identified through database searching. After the exclusion of studies on the basis of irrelevant titles and abstracts such as articles not written in English; studies on assessment of molecular or biomarker profiling, and on the estimation of body and ocular pharmacological concentration of CCS after their administration; evaluation of alternative pharmacological approaches to CCS in RRD surgery or failure to meet inclusion criteria, 23 studies were assessed as eligible and included in our review Figure 1.

Study selection process. Preoperative Use Figure 1. Study Six studies regarding the preoperative useselection of CCSprocess. Their main characteristics and results are shown in Table 1. Four had a prospective design but 3. Preoperative Use only two of these were randomized; the other three of the seven studies were retrospective [27—32].

Our Six studies regarding systematic the preoperative review found use of CCS that CCS are widely usedwere identified by preoperatively inour literature addition review.

Associations of []. RRDCD to wassurgery to treat first, described patients affected in and by RRD associated is characterized with choroidal by the detachment detachment of the CD choroid and, [].

Preoperative use of corticosteroid drugs in retinal detachment surgery. Anatomic primary success Anatomic final success Sharma T et al. BCVA improvement: 2. Pre-operative CD 16 eyes ST injection of Systemic and - 4 eyes in TA group vs. Ciliary body and received 4 mg of and pre- 2. Sign on 19 eyes phosphate 0.

Retinal 2. Group 2 Yu Y et al. Factors variables of 20 mg PVR grade D vs. GROUP 4 41 eyes group 2 IVT for 5 to 7 days group 3 Regarding the vascular pathogenesis, the hypotony induced by the RD has been assumed to lead to CD by stimulating dilatation and hyper-permeability of choroidal blood vessels [38]. In addition, edema of the ciliary body itself could further reduce the production of aqueous humor with a positive feedback loop and consequently more hypotony.

Other authors [6] have shown inflammatory processes playing an important role in the development of CD associated with RRD and hypothesized that a severe uveitic process, secondary to RD, could occur and lead to the exudation of choroidal blood vessels, leakage of fluid and subsequent choroidal detachment with secondary hypotony, creating a vicious circle.

This theory found support in the overexpression of inflammatory cytokines and proteins such as migration inhibitor factor MIF and soluble intercellular adhesion molecule1 sICAM-1 observed by Dai et al. According to these pathogenic theories, the pre-operative use of CCS could play an important role in preparing patients affected by RRDCD for surgery, in order to increase IOP and reduce CD by reducing the permeability of choroidal blood vessels, inhibiting inflammatory reactions and cellular proliferation, and stabilizing BRB [27—32].

Intraoperative Use From our systematic review of the literature, we identified 11 studies [40—50] investigating the effects of steroids as an intraoperative adjuvant in RRD surgery. Of the eleven studies, seven had a prospective design but only five were randomized; three studies were retrospective and one study was a case report.

Overall, in all of these studies, the main reason for the intraoperative use of CCS in combination with PPV was either the treatment of PVR, [41,42,44,48] when associated with RRD, or its prevention, in cases of RRD with a high risk of PVR development [45], and the prevention of postoperative complications such as macular pucker [43], persistent subretinal fluid SRF [46,48] and cystoid macular edema [46,48].

Although the pathogenesis of PVR is complex and still remains partially unclear, the role of inflammation in the pathogenesis of PVR has been widely accepted and three overlapping biological processes have been identified as major triggers.

These are: 1 Retinal pigment epithelial RPE and glial cellular migration into the vitreal cavity and onto the retinal surface, respectively ; 2 cellular proliferation extravasations of blood components such as fibrin, elastin, fibronectin, growth factors, and cytokines secondary to blood—retinal barrier breakdown ; and 3 cellular contraction due to the deposition of the extracellular matrix and collagen synthesis.

Connective tissue factor CTS-F promotes cellular migration and proliferation and stimulates the production of extracellular matrix with the consequent formation of membranes.

All these factors stimulate cellular migration, cellular proliferation, deposition of cellular matrix, and creation of contractile membranes growth factor and cytokines hypothesis [55].

The role of macrophages has been recently highlighted. They have a multifactorial action that includes the secretion of growth factors such as PDGF and their differentiation into fibroblast-like cells macrophage hypothesis [55]. Several drugs have been proposed as an adjunctive treatment for preventing postoperative PVR. Corticosteroid treatment can modulate both the inflammatory and proliferative pathways of PVR by stabilizing the blood—retinal barrier and suppressing local growth factors and inflammatory cytokines.

This could finally lead to the inhibition of the proliferation of RPE cells, fibroblasts, and myofibroblasts, [55,56]. The advantage of a DEX implant is the slow release of active dexamethasone within the vitreous chamber for up to six months, with a single injection, and with a similar clearance in vitrectomized and non-vitrectomized eyes [58].

However, 4 mg TA intravitreal injection has been reported to have an effect that lasts up to three months [59] with a six times quicker clearance in vitrectomized than in non vitrectomized eyes [60]. Intraoperative use of corticosteroid drugs in retinal detachment surgery.

BCVA improvement 4 mg 1. Retinal reattachment rate Retinal Group 2 from 2. Rate of recurrent PVR grade C: Macular pucker Reattachment rate: Macular pucker: Post-operative complications: 3. Additional surgery Additional surgery: Group 1 vs. PVR development: Reibaldi M et al. BCVA improvement: 1. Incidence of persistence SRF: 3. Extent of detachment: case series No cataract progression 5. Post-operative 33 eyes group 1 vs. BCVA improvement patient 1: from 0.

BCVA improvement 0. Stable retinal reattachment with SO: 5 out of 5 eyes 3. Hypotony at least achieving a visual acuity of 1. Macular findings at 6 months: additional surgical 2.

IOP at least 1 episode : - Macular edema intervention at 6 months group 1 United Kingdom 3. Macular findings at 70 eyes : group 1 Development DEX implant 4. Retinal reattachment: Tractional retinal 4.

Retinal attachment 15—37 months Korea patients with RD implant 2. Complete response IV 15 min before the Severity standardized 10 mL IV at the start of vs. It has also been reported to have a longer action compared to the DEX implant in vitrectomized eyes [62].

Among the 11 studies reviewed, we identified 6 studies investigating the use of intravitreal triamcinolone IVTA and 3 studies assessing the use of the DEX implant in addition to surgery to treat RRD.

Moreover, we found one study that investigated the use of intravenous dexamethasone during surgery. No studies regarding the intraoperative use of the FA implant were found. The main characteristics and results of these studies are shown in Table 2.

Previous experimental and clinical research demonstrated that IVTA was not significantly retinotoxic when used during vitrectomy without silicone oil SO endotamponade [63—66].

On the other hand, toxicity is still controversial when IVTA in different doses: 2, 4, 10, and 20 mg is used during vitrectomy with SO endotamponade [67—69].

Kivilcim et al. However, Perkins et al. Moreover, Spritzer [70], in an experimental model, observed that TA injected into the vitreous cavity filled with SO precipitated at the lower border of the endotamponade bubble, without mixing with it and causing a possible cytotoxic effect on the retina.

In conclusion, it is still unclear which is the best timing for TA injection: soon before silicone oil injection [40] or at the end of the operation into the silicone oil bubble filling the vitreous chamber [41]. Fewer data exist about a DEX implant into silicone oil-filled eyes. One author, using an in vitro model, showed that when DEX is injected into vitrectomized silicone oil-filled eyes, SO modified and increased DEX release over a one-year period [71].

To date, in vivo information is limited to a few case reports and only one recent randomized clinical trial RCT , with the latter showing results that a DEX implant is generally well tolerated. On the other hand, Bakri and Alniemi [72] reported epiretinal fibrosis development around the implant at the 6th postoperative week, leading to recurrent retinal detachment that needed vitrectomy, removal of the implant, and peeling of epiretinal proliferation.

Postoperative Use Five studies assessing the postoperative use of CCS oral or topical were identified by our literature review. Their main characteristics and results are shown in Table 3.

Postoperative use of corticosteroids in retinal detachment surgery. Macular edema treated by SB group 2 Macular edema within 4. SRF - Incidence 6 weeks after operation : group 1 SRF incidence group 1A Enter the email address you signed up with and we'll email you a reset link.

Need an account? Click here to sign up. Download Free PDF. Pars Plana Vitrectomy. Ahmed Al bayar. A short summary of this paper. Download Download PDF. Translate PDF. These individuals include those affected by proliferative diabetic retinopathy, proliferative vitreoretinopathy, andendophthalmitis or patients otherwise regarded as hopeless. Ahmad A. It is a hydrophilic gel that mainly serves the optical functions.

In addition, it mechanically stabilizes the volume of the globe and is a pathway for nutrients to reach the lens and retina. Structure: The normal youthful vitreous gel is composed of a network of randomly-oriented collagen fibrils interspersed with numerous spheroidal macromolecules of hyaluronic acid.

The collapse of this structure with age or otherwise leads to conversion of the gel into sol. The vitreous body can be divided into two parts: the cortex and the nucleus the main vitreous body 1: Cortical vitreous. It lies adjacent to the retina posteriorly and lens, ciliary body and zonules anteriorly.

The density of collagen fibrils is greater in this peripheral part. The condensation of these fibrils form a false anatomic membrane which is called as anterior hyaloid membrane anterior to ora serrate and posterior hyaloid membrane posterior to ora. The attachment of the anterior hyaloid membrane to the posterior lens surface is firm in the young and weak in the elderly whereas posterior hyaloid membrane remains loosely attached to the internal limiting membrane of the retina throughout life.

These membranes cannot be discerned in a normal eye unless the lens has been extracted and posterior vitreous detachment has occurred. It has a less dense fibrillar structure and is a true biological gel. It is here where liquefactions of the vitreous gel start first. Microscopically the vitreous body is homogenous, but exhibits wavy lines as of watered silk in the slit-lamp beams.

Down this canal ran the hyaloid artery of the foetus. Attachments : The part of the vitreous about 4 mm across the ora serrata is called as vitreous base, where the attachment of the vitreous is strongest. The other firm attachments are around the margins of the optic disc, foveal region and back of the crystalline lens by hyloidocapsular ligament of Wieger.

Gross anatomy of vitrous. The physiological function of the vitreous body involves supporting adjacent posterior segment structures, providing an ocular refractive medium, and acting as a cell barrier to inhibit cell migration from the retina to the vitreous cavity.

With age, the natural vitreous body gradually shrinks and collapses during the course of syneresis. This phenomenon may eventually lead to posterior vitreous detachment and can play a crucial role in the formation of retinal breaks which result in rhegmatogenous retinal detachment if untreated.

Pars plana Vitrectomy : Pars plana vitrectomy PPV is a surgical procedure that involves removal of vitreous gel from the eye. The procedure derives it name from the fact that vitreous is removed i.

History: PPV was first introduced in , when Machemer invented a single port, multifunctional gauge cutter called" the vitreous infusion suction cutter " VISC. PPV was a major advance because for the first time it allowed for the removal of vitreous through a closed system, rather than through an open sky technique.

Over the past several years, the development of small incision transconjunctival, sutureless PPV has led to a major shift in how many diseases are treated in the operating room.

Sugical indications : Pars plana vitrectomy is commonly recommended for the following conditions. Surgical techniques : Pars plana vitrectomy is a highly sophisticated microsurgery which can be performed by using two type of systems: 1.

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Choroidal Neovascularization.