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Numerous neurological disorders have a pathophysiology that involves an increase in free radical production in the brain. Quercetin (QER) is a nutraceutical compound that shields the brain against oxidative stress-induced neurodegeneration. Nonetheless, its low oral bioavailability diminishes brain delivery. Therefore, the current study aimed to formulate QER-loaded transferosomal nanovesicles (QER-TFS) in situ gel for QER brain delivery via the intranasal route. This study explored the impacts of lipid amount, edge activator (EA) amount, and EA type on vesicle diameter, entrapment, and cumulative amount permeated through nasal mucosa (24 h). The optimum formulation was then integrated into a thermosensitive gel after its physical and morphological characteristics were assessed. Assessments of the optimized QER-TFS showed nanometric vesicles (171.4 ± 3.4 nm) with spherical shapes and adequate entrapment efficiency (78.2 ± 2.8%). The results of short-term stability and high zeta potential value (−32.6 ± 1.4 mV) of QER-TFS confirmed their high stability. Compared with the QER solution, the optimized QER-TFS in situ gel formulation exhibited sustained release behavior and augmented nasal mucosa permeability. CT scanning of rat brains demonstrated the buildup of gold nanoparticles (GNPs) in the brains of all treatment groups, with a greater level of GNPs noted in the rats given the transferosomal gel. Additionally, in vitro studies on PCS-200-014 cells revealed minimal cytotoxicity of QER-TFS in situ gel. Based on these results, the developed transferosomal nanovesicles may be a suitable nanocarrier for QER brain targeting through the intranasal route.

Oxidative stress is a leading cause of different diseases. Genistein is a valuable bioflavonoid possessing antioxidant and anti-inflammatory activity but unfortunately, it suffers from low aqueous solubility, extremely poor bioavailability and first pass effect when used in its pure state. The aim of this work was to formulate and characterize genistein-loaded highly phospholipid-containing lipid nanocarriers to improve oral bioavailability and pharmacodynamic performance. Lipid nanocarriers were prepared by the emulsification/sonication technique. The influence of phospholipid percentage (1%-10%) on physicochemical properties, drug release and stability was investigated. The particle size, zeta potential and EE% were in ranges from 211.9 ± 21.6 to 342.3 ± 7.9 nm, -11.6 ± 1.7 to -19.4 ± 3.1 mV and 78.5 ± 4.7% to 92.2 ± 1.9%, respectively. Drug release was less predominant in the case of SLN formulations when compared to corresponding NLC formulations. High phospholipid percentage produced less stable formulations in terms of particle size growth, gelation and heterogeneous particle distributions. DSC, FT-IR and XRD tools revealed that genistein has existed in an amorphous form in NLC4. The bioavailability of NLC4 was approximately 2.6-fold greater than that of conventional suspension. Additionally, lipid peroxidation in liver homogenate and histopathological alterations in liver and kidney sections were particularly improved, providing a promising strategy for oral administration of genistein.

Olive oil is a vegetable oil which has been successfully used as a skin penetrating agent. Acidity of olive oil is considered as one of the characteristic properties of olive oil. Olive oil acidity was selected as a parameter under investigation for evaluation of skin permeability. The acidities of the three investigated olive oils are varying from 0.75±0.16 to 2±0.17. Olive oil with acidity equals 2.0 showed the highest skin permeation for 12 h and cutaneous deposition with significant difference compared to the permeation values of 0.75 and F1.4 acidities. Results of cutaneous secretion of cytokines suggested that higher penetration was accompanied higher cytokines’ secretions. Olive oil with acidity equals 2.0 also showed more prominent skin changes which suggested to be due to acidity and fatty acids’ content. These results suggest that olive oil might improve the epidermal permeability, which is more pronounced in highly acidic olive oil, through weakening of skin barriers followed by acting of cytokines on re-building effective barriers. Finally, based on the current study, highly acidic olive oil is more efficient skin permeation enhancer vehicle than less acidic ones and can be efficiently used in formulation of cutaneous drug delivery systems.

This work designates EthoLeciplex, a vesicular system consisting of phospholipid, CTAB, ethanol and water, as an innovative vesicular system for cutaneous/transfollicular minoxidil (MX) delivery. MX-loaded EthoLeciplex was fabricated by one-step fabrication process. Formulations were designed to study the effects of drug/phospholipid ratio, CTAB/phospholipid ratio, and ethanol concentration on vesicular size, PDI, surface charge and EE%. The optimized formulation was characterized by

Diabetes is one of the most common metabolic disorders often associated with hyperglycemia, altered carbohydrate, lipid, and protein metabolism. Type 2 diabetes is the most common type of diabetes associated with the disturbance of the normal level of insulin secretion from pancreatic β-cell. The current treatment of diabetes is done with semi-synthetic and synthetic drugs, but it is associated with adverse effects. Now, scientific community searches for new herbal bioactive as a replacement for successful management of the disease. Primitively bioactive compounds from herbs served as the backbone of medical therapy. The significant scientific facts and profitable dormant of ancient medicines are directed to increased global attention for herbal remedies. Herbal remedies are composed of an intricate blend of several bioactive molecules with accountable pharmacological action. Numerous published reports claim the pharmacological action of herbal remedies of the exact phytoconstituents. It is imperative to understand the pharmacokinetics of such phytoconstituents, with only a few phytoconstituents whose pharmacokinetic properties have been reported, and it requires to explore the pharmacokinetic property of other phytoconstituents. There are many bioactive plants that have antidiabetic properties such as Capsicum (chili pepper), Vitis vinifera (grape vine), Glycyrrhiza, Cinnamomum extract, Ervatamia microphylla, Trigonella foenum-graecum, and Moringa oleifera. This review highlights comprehensive information on pharmacokinetics and clinical efficacy of different bioactive constituents which is obtained from various plants that may afford as antidiabetic therapeutics.

Luteolin is an excellent flavone possessing several beneficial properties such as antioxidant and anti-inflammatory effects which are interesting for skin delivery. Development of an appropriate skin delivery system could be a promising strategy to improve luteolin cutaneous performance.So, the main aim of this work was to fabricate, characterize and evaluate phospholipid-based luteolin-loaded lipid nanocapsules for skin delivery. The influence of phospholipid/oil ratio, surfactant type and chitosan coating were investigated. The prepared formulations underwent in vitro assessment and the selected formulations were evaluated ex vivo and in vivo. The mean diameters of investigated formulations varied between 174 nm and 628 nm while zeta potential varied between -25.7 ± 4.8 mV and 6.8 ± 1.7 mV. Increasing in phospholipid/oil ratios resulted in decrease in particles size with little effect on zeta potential and drug encapsulation. Cremophor EL showed the lowest particle sizes and the highest drug encapsulation. Chitosan coating shifted zeta potential towards positive values. Structural analyses showed that luteolin is incorporated into lipid core of nanocapsules. Selected formulations (LNC4 and LNC13) exhibited sustained in vitro release and antioxidant activity. LNC13 (chitosan coated) showed higher flux (0.457 ± 0.113 µg/cm

The aim of this work was to prepare and optimize mucoadhesive nanostructured lipid carrier (NLC) impregnated with fluconazole for better management of oral candidiasis. The NLCs were fabricated using an emulsification/sonication technique. The nanoparticles consisted of stearic acid, oleic acid, Pluronic F127, and lecithin. Box-Behnken design, artificial neural networking, and variable weight desirability were employed to optimize the joint effect of drug concentration in the drug/lipid mixture, solid lipid concentration in the solid/liquid lipid mixture, and surfactant concentration in the total mixture on size and entrapment. The optimized NLCs were coated with chitosan. The nanoparticles were characterized by surface charge, spectroscopic, thermal, morphological, mucoadhesion, release, histopathological, and antifungal properties. The nanoparticles are characterized by a particle size of 335 ± 13.5 nm, entrapment efficiency of 73.1 ± 4.9%, sustained release, minor histopathological effects on rabbit oral mucosa, and higher fungal inhibition efficiency for an extended period of time compared with fluconazole solution. Coating the nanoparticles with chitosan increased its adhesion to rabbit oral buccal mucosa and improved its anti-candidiasis activity. It is concluded that mucoadhesive lipid-based nanoparticles amplify the effect of fluconazole on

There are many synthetic drugs in literature have been utilized in healing of the wounds although the natural product specially antioxidants can offer similar if not better biological activity in t...

In the last few decades, several natural bioactive agents have been widely utilized in the treatment and prevention of many diseases owing to their unique and versatile therapeutic effects, including antioxidant, anti-inflammatory, anticancer, and neuroprotective action. However, their poor aqueous solubility, poor bioavailability, low GIT stability, extensive metabolism as well as short duration of action are the most shortfalls hampering their biomedical/pharmaceutical applications. Different drug delivery platforms have developed in this regard, and a captivating tool of this has been the fabrication of nanocarriers. In particular, polymeric nanoparticles were reported to offer proficient delivery of various natural bioactive agents with good entrapment potential and stability, an efficiently controlled release, improved bioavailability, and fascinating therapeutic efficacy. In addition, surface decoration and polymer functionalization have opened the door to improving the characteristics of polymeric nanoparticles and alleviating the reported toxicity. Herein, a review of the state of knowledge on polymeric nanoparticles loaded with natural bioactive agents is presented. The review focuses on frequently used polymeric materials and their corresponding methods of fabrication, the needs of such systems for natural bioactive agents, polymeric nanoparticles loaded with natural bioactive agents in the literature, and the potential role of polymer functionalization, hybrid systems, and stimuli-responsive systems in overcoming most of the system drawbacks. This exploration may offer a thorough idea of viewing the polymeric nanoparticles as a potential candidate for the delivery of natural bioactive agents as well as the challenges and the combating tools used to overcome any hurdles.

The objective of the current work was to develop and evaluate suppository dosage form in order to improve ranitidine bioavailability as a substitute to the oral administration. Suppocire (different grades), Witepsol W25 and polyethylene glycol (PEG) were used as suppository bases and prepared by molding method. The prepared formulations were examined for hardness, disintegration time, melting point, content uniformity, drug release, stability and bioavailability. The hardness ranged from 3.82 to 12.53 kg and disintegration time from 13.32 to 28.22 min. The melting points of fatty bases had values from 33.94 to 36.82±0.36ºC while PEG based suppositories melting points were directly proportional chain length. Higher content uniformity was observed in PEG based suppositories due to easy incorporation of RT into water soluble base. Release was affected by hydroxyl value and molecular weight (in cases of fatty and PEG bases respectively). All formulations were relatively stable after 12 months. In vivo studies of all formulations exhibited double peak phenomena. PEG based formula (S8) showed significant higher Cmax (10.05±1 μg/ml) and AUC0-12 (58.313±3.9 µg.h/mL) than fatty bases and oral solution. In conclusion, rectal administration of S8 could be prepared as an alternative to the oral dosage form to improve bioavailability and overcome the first-pass metabolism.

Background Although few studies have used ketamine for induction and maintenance of pediatric anesthesia, official dosage recommendations are lacking. This study evaluates the outcomes of adult anesthetic doses in a pediatric population through pharmacokinetic modeling and computer simulations in an attempt to recommend an adequate ketamine dosing regimen. Methods Ketamine plasma concentration-time data in 19 children (age 8 months to 16 years; weight 5.5 to 67 kg) were analyzed according to a non-compartmental pharmacokinetic approach. The relationship between pharmacokinetic parameters and demographic covariates was mathematically characterized. A one-compartment open model was implemented to simulate the plasma profile following administration of 1-4.5 mg/kg IV bolus dose and 0.1-0.5 mg/kg/min continuous infusion of ketamine and to predict anesthesia onset and offset. Key results Pharmacokinetic parameters determined were clearance 0.025 ± 0.008 L/kg/min; distribution volume 3.3 ± 1.3 L/kg; half-life 2.6 ± 1 h; and mean residence time 2.3 ± 0.64 h. Body weight was the best predictor of clearance and distribution volume according to a 0.75-power model. Using weight to scale doses was associated with limited variability in simulated concentrations. Ketamine administered as 2.25 mg/kg IV bolus dose, followed by 0.1 mg/kg/min continuous IV infusion enables anesthesia initiation within 3 minutes and maintains it for 3 hours. Conclusions & inferences Weight-based dosing minimizes age-dependent variation in the plasma concentration of ketamine. Low-to-intermediate adult doses are suitable for induction and maintenance of safe anesthesia in children undergoing short-term surgical operations. However, this finding requires validation in controlled clinical trials before it is adopted into surgical standard practices.

Delayed hemolytic transfusion reactions (DHTRs) occur in patients who have received transfusions in the past. These patients may have very low antibody titers that are undetectable on pretransfusion testing, so that seemingly compatible units of red blood cells (RBCs) are transfused. DHTRs are a potentially life-threatening complication of sickle-cell disease (SCD) treatment. In SCD, DHTRs appear to be an immune process that develop because of differences in erythrocyte antigens between blood donors and patients. Aim:DHTR is one of serious complication of blood transfusion that happens due to alloimmunized which is lead to hyperhaemolysis syndrome , DHTR can be managed by steroid and Intravenous immunoglobulin ( IVIG ) and prevented by accurate records with extended matching for certain population. Methodology:The consent of the patient and his family was obtained to publish and highlight his health condition in detail and to follow up with the case to match the research results and work on it under the framework of case reporting. Conclusion:DHTR can be managed by steroid and Intravenous immunoglobulin ( IVIG ) with good outcomes,DHTR can be prevented by means of accurate records, extended matching for certain population with high risk of developing alloantibodies such as individuals with SCD and B-thalassemia with proper handling of administration of blood product and proper notation in the patient medical records and blood bank records as well as the use of medical card for patient to known RBC alloantibodies. &nbsp

There are many synthetic drugs in literature have been utilized in healing of the wounds although the natural product specially antioxidants can offer similar if not better biological activity in that regard. Genus Sophora is well known to contain flavonoids and phenolic compounds which have antioxidant and inflammatory effects. So, the aim of the current study was to develop and evaluate chitosan/gelatin based

Fibrotic strictures are one of the most severe complications of Crohn’s Disease (CD). They occur in about 50% of patients at five years and in 70% at ten years of the diagnosis. The only treatment available for symptomatic fibrotic strictures is surgical resection and endoscopic dilation. Both strategies are associated with a high rate of recurrence, and with multiple surgical resections, which pose the threat of surgical morbidity and short bowel syndrome. Therefore, it is crucial to identify, early, the patients more prone to develop intestinal fibrosis to intensify follow-ups, switch to more aggressive treatments, and suggest lifestyle modifications. Scarce data are available concerning biomarkers and genetic determinants to predict which patient will develop intestinal fibrosis. Biologic or clinical markers would be useful to determine this subgroup of CD patients and to predict the onset of intestinal fibrosis and, ideally, its severity. Furthermore, the identification of environmental risk factors may suggest lifestyle changes aimed at modifying the natural course, thus decreasing the risk of complicated CD. In this review, we will critically revise clinical, environmental, genetic, and serologic factors that have been associated with a complicated CD course with a particular focus on the fibrostenosing phenotype and their possible implications as predictive factors of intestinal fibrosis.

Objectives This study aims to develop thermosensitive gel containing soy isoflavone (antioxidant and anti-inflammatory natural agent) alginate microspheres for enhancement of wound-healing performance. Methods Soy isoflavone microspheres were prepared by ionic cross-linking method and optimized using the Box–Behnken optimization design. Formulations were characterized in terms of particle size, encapsulation efficiency and equilibrium swelling degree. The optimized formula was incorporated in Pluronic F127 gel base and examined for in vivo wound-healing efficacy. Key findings Results showed mean particle size between 18 and 25 μm, encapsulation efficiency of over 75% and equilibrium swelling degree over 1.9. Thermal analysis indicated interaction between alginate and CaCl2 and embedding of soy isoflavone in microspheres. In vivo wound-healing efficacy showed significant advance in re-epithelization, mature collagen synthesis and proangiogenesis. Immunohistochemical investigation exhibited promising alpha-smooth muscle actin immunopositive cells expression, fibroblast activation and expression of proliferating cell nuclear antigen (proliferation marker) in the epidermis and in the dermis. Conclusions The developed formulation would appear to be a promising topical preparation for accelerating healing process.

Long-acting preparations containing the antipsychotic paliperidone for intramuscular injection has drawn considerable attention to achieve harmless long-term treatment. This study aimed to develop paliperidone loaded polycaprolactone (PCL) nanoparticles and investigate the influence of PCL/drug ratio, stabilizer type, and chitosan coating on physicochemical properties, protein adsorption, and cellular toxicity. Results showed that chitosan coating produced enlarged particle sizes, shifted the surface charges from negative into positive and did not influence encapsulation efficiencies. Chitosan coating relatively sustained the drug release especially in pluronic stabilized formulations. Pluronic F127 based formulations exhibited the least protein adsorption (384.3 μg/mL). Chitosan coating of Tween 80 and polyvinyl alcohol stabilized formulations significantly (p < 0.05) increased protein adsorption. Cellular viability was concentration-dependent and negatively affected by stabilizers. All formulations did not show cellular death at 1.56 μg/mL. Inflammatory responses and oxidative stress were less affected by Tween 80 compared with other stabilizers. Chitosan minimized all aspects of cellular toxicity. Collectively, stabilizer type and chitosan coating play critical roles in developing safe and effective long-acting PCL nanoparticles intended for parenteral drug delivery. The coated formulations containing Tween 80 and Pluronic F127 as stabilizers are warranted a future in vivo study to delineate its safety and efficacy profiles.

This study aims to overcome most of the obstacles that face oral administration of progesterone. Fatty alcohols (cetyl, cetostearyl and 1:1 mixture) containing NLCs were thought to be one of the most relevant systems based on progesterone drawbacks as acid sensitivity and poor solubility. Formulations were prepared characterized for physicochemical evaluation, in vitro release, in vitro stability in gastric fluid, short term stability, interaction possibility and ex vivo permeation studies. The results showed nanorange particle size with major influence of fatty alcohol concentration. In vitro stability in gastric fluid and release results suggested protection of formulation from gastric environment with controlling the drug release as a function of fatty alcohol concentration. Infrared and thermal analyses showed interaction among fatty alcohol, stearic acid and progesterone. Ex vivo results showed that formulations significantly (p

Luteolin is a valuable natural drug for the treatment of oxidative stress associated diseases, but its use is hindered by gastric instability and poor bioavailability. Given that hybrid polymeric nanoparticles may have potential applications in the design of oral drug delivery systems, this study aims to develop luteolin loaded hybrid polylactic acid/Eudragit L100 nanoparticles. By nanoprecipitation, different formulations were prepared, optimized and characterized in terms of physicochemical properties, stability and in vivo performance. The optimum formulation presented particle size of 452.23 ± 22.4 nm, zeta potential of 0.92 mV ± 0.04, entrapment efficiency of 71.02 ± 14.6% and loading efficiency of 11.21 ± 3.1%, in accordance with the values predicted created by Box-Behnken design. In vitro, the system was capable of protection of luteolin in simulated gastric fluid, while a release study confirmed the controlled luteolin release pattern. Interaction between system components was verified through infrared and thermal analysis. The maximum plasma concentration of luteolin in the optimized formulation was significantly improved (212.2 %, p

The study was conducted to evaluate the potential application of nanocapsules and nanospheres as topical drug delivery systems for indomethacin (as model drug). Both were prepared by nanoprecipitation using poly (ɛ-caprolactone) and hydroxypropyl β-cyclodextrin polymers and evaluated for morphology, particle size, zeta potential, EE% and in vitro drug release then incorporated in methylcellulose and Carbopol 940 gel bases and evaluated for in vitro release. The selected formulations and market product were evaluated for ex vivo human skin permeation and anti-inflammatory and analgesic activities by paw edema and hot plate methods respectively. Results showed that nanocapsules had slight higher EE% and larger particle sizes than nanospheres. In vitro release and zeta potential were nearly similar. Methylcellulose exhibited higher in vitro release than Carbopol 940 after 3 h (except NS2). Ex vivo skin permeation studies showed significant higher cumulative amount of IND (and flux) from NC1/MC and NS1/MC (1573.06 ± 14.23 µg/cm 2 and 1452.24 ± 23.18 µg/cm 2 respectively) than market product. They also showed enhancement ratio and permeability coefficient rate of ∼1.5 and ∼2 respectively. NC1/MC proved to be significantly higher pharmacodynamic effects than market product. All results showed that NC1/MC could provide a promising formula as a topical delivery of indomethacin.

The main objective of this study was to prepare and characterize oleogel as potential carrier for quercetin skin delivery. The formulations were prepared by adding olive oil (5–30%) to Pluronic F127 hydrogel and were evaluated for particle size, zeta potential, viscosity in vitro quercetin release and stability, and were compared with that of Pluronic F127 hydrogel. The selected formulation was characterized for its interaction possibility, ex vivo skin permeation and skin histological changes and safety. The particle sizes ranged from 345.3 ± 5.3 nm to 401.5 ± 2.8 nm, and possessed negative charges. The viscosities of the formulations were found in the range of 6367–4823 cps with inverse proportionality to olive oil percentage while the higher percentages showed higher quercetin release. Percentages of 25% and 30% olive oil showed instability pattern under the conditions of accelerated stability studies. Differential scanning calorimetry verified the existence of quercetin in micellar aggregation and the network in the case of hydrogel and oleogel respectively. Ex vivo skin permeation showed an improved skin permeation of quercetin when 20% olive oil containing oleogel was used. Skin histology after 10 days of application showed stratum corneum disruption and good safety profile. Based on these findings, the proposed oleogel containing 20% olive oil denotes a potential carrier for topical delivery of quercetin.

Aim s: This Study was performed to evaluate the quantitative distribution of mannitol (model hydrophilic molecule) and corticosterone (model lipophilic molecule) in human skin following the application of different vesicular systems (liposome, ethosome and invasome). Methodology: Vesicular systems were prepared by thin film hydration method and particle size, particles distribution, zeta potential and in vitro human skin penetration and skin deposition were evaluated. Results and Discussion: Results showed that all of the investigated vesicular systems had almost nanometric size ranging from 67.46±0.25nm and 108.3±0.95nm with low polydispersity (PDI

The main objective of this study was to develop, characterize and evaluate the potential use of dapsone-loaded nanostructured lipid carriers (NLCs) as a topical treatment for acne. Differently charged NLC formulations were successfully prepared using an emulsification/sonication method. The particle sizes ranged from 106.2 ± 5.6 nm to 151.3 ± 7.4 nm, and the NLCs possessed the predicted surface charges, depending on the emulsifier used (Tween 80, Transcutol P, or cetyltrimethylammonium bromide). The entrapment efficiencies ranged from 76.5 ± 3.8% to 91.1 ± 3.9%. Selected formulations were assessed for possible interactions, in vitro release, ex vivo skin permeation, pharmacological efficacy and safety compared with a hydroalcoholic solution. Dapsone was embedded in the lipid matrix of NLCs and behaved as controlled release system with a good occlusive effect. Dapsone-loaded cationic NLC formulation enhanced the skin permeation of dapsone, increase the amount of dapsone retained in the skin in controlled manner, and improved the anti-rosacea activity. Based on these encouraging results, cationic NLC represents a promising carrier for the safe topical delivery of dapsone.

Khaled AG ShalabyOpthamology Department, Al-Azhar University, Cairo, Egypt; Chief Vitreoretinal Service, Dr Soliman Fakeeh Hospital, Jeddah, Saudi ArabiaAbstract: Relaxing retinotomies and retinectomies are used in the presence of retinal shortening resulting from retinal incarceration or fibrous proliferation and contraction that prevents contact of the retina with the retinal pigment epithelium. The peripheral retina is usually cut or excised to preserve function of the posterior retina which is more visually significant.Objective: To investigate the techniques, therapeutic effects, indications, and complications of relaxing retinotomies and retinectomies for complicated retinal detachment with severe proliferative vitreoretinopathy (PVR).Methods: Thirty eight eyes of 38 patients of complicated retinal detachment with severe PVR were recruited for a noncomparative retrospective study. They were operated on and followed-up for at least six months. The operative technique included buckling, vitrectomy, peeling, relaxing retinotomy and/or retinectomy, intraocular tamponade, and laser treatment.Results: Retina was reattached in 34 (89.5%) eyes in operations. Retinal detachment was recurrent in seven eyes in follow-up, in which the retina was reattached again in two eyes by a second operation. The final success rate was 76.3% (29 eyes out of 38 eyes). Visual acuity was perception of light with bad projection in 35 (92%) eyes and hand motion in three (8%) eyes before operation. Visual acuity was better than 4/60 in 23 eyes (60.5%) after operation. The complications included iatrogenic retinal breaks, bleeding from the retinotomy site, hypotony, and recurrent fibrous proliferation from the retinotomy site.Conclusion: Retinotomy and retinectomy can improve the curative effect of complicated retinal detachment. There are potentially serious complications of these maneuvers and they should not be performed if less aggressive measures will suffice.Keywords: relaxing retinotomy, retinectomy, proliferative vitreoretinopathy, recurrent retinal detachment, iatrogenic retinal breaks, intraoperative hemorrhage, intraocular tamponade, hypotony