RESUMEN

This study describes the development of hydrogel formulations with ionic crosslinking capacity and photocatalytic characteristics. The objective of this research is to provide an effective, accessible, "green", and facile route for the decontamination of chemical warfare agents (CWAs, namely the blistering agent-mustard gas/sulfur mustard (HD)) from contaminated surfaces, by decomposition and entrapment of CWAs and their degradation products inside the hydrogel films generated "on-site". The decontamination of the notorious warfare agent HD was successfully achieved through a dual hydrolytic-photocatalytic degradation process. Subsequently, the post-decontamination residues were encapsulated within a hydrogel membrane film produced via an ionic crosslinking mechanism. Polyvinyl alcohol (PVA) and sodium alginate (ALG) are the primary constituents of the decontaminating formulations. These polymeric components were chosen for this application due to their cost-effectiveness, versatility, and their ability to form hydrogen bonds, facilitating hydrogel formation. In the presence of divalent metallic ions, ALG undergoes ionic crosslinking, resulting in rapid gelation. This facilitated prompt PVA-ALG film curing and allowed for immediate decontamination of targeted surfaces. Additionally, bentonite nanoclay, titanium nanoparticles, and a tetrasulfonated nickel phthalocyanine (NiPc) derivative were incorporated into the formulations to enhance absorption capacity, improve mechanical properties, and confer photocatalytic activity to the hydrogels obtained via Zn2+-mediated ionic crosslinking. The resulting hydrogels underwent characterization using a variety of analytical techniques, including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), viscometry, and mechanical analysis (shear, tensile, and compression tests), as well as swelling investigations, to establish the optimal formulations for CWA decontamination applications. The introduction of the fillers led to an increase in the maximum strain up to 0.14 MPa (maximum tensile resistance) and 0.39 MPa (maximum compressive stress). The UV-Vis characterization of the hydrogels allowed the determination of the band-gap value and absorption domain. A gas chromatography-mass spectrometry assay was employed to evaluate the decontamination efficacy for a chemical warfare agent (sulfur mustard-HD) and confirmed that the ionic crosslinked hydrogel films achieved decontamination efficiencies of up to 92.3%. Furthermore, the presence of the photocatalytic species can facilitate the degradation of up to 90% of the HD removed from the surface and entrapped inside the hydrogel matrix, which renders the post-decontamination residue significantly less dangerous.

RESUMEN

PURPOSE: To propose a new technique with an "old" tool to allow for better intraocular foreign body (IOFB) grasping and manipulation during mininvasive vitreoretinal surgery. METHODS: The authors report herein their technique on seven eyes, diagnosed with posterior IOFBs, in which the surgery consisted of a 23-gauge vitrectomy, using, for IOFB grasping, a Grieshaber DSP 23-gauge Eckardt forceps, properly modified intraoperatively. Such result was achieved by enlarging the forceps opening bite, according to the IOFB size. RESULTS: In all patients, IOFBs were removed using the modified 23-gauge Grieshaber Eckardt forceps. In 6 cases, a combined phacovitrectomy was performed, and the IOFB expressed through the corneal phacoincision; in one phakic patient, the removal was performed through the sclerotomy, extended just as needed. CONCLUSION: The Grieshaber Eckardt forceps commonly used in MIVS can be used in IOFB surgery for a scleral or corneal removal. In case of IOFB bigger than 1 mm, enlarging the forceps bite according the IOFB size provides a firm and safe grip, allowing the surgeon to complete the surgery without switching to bigger and more traumatic instrumentation, reducing collateral damage and shortening the surgery time.

Asunto(s)

RESUMEN

The present work reveals a comprehensive decontamination study on real and simulated biological and chemical warfare agents (BCWA). The emphasis was on evaluating the antimicrobial activity against real biological warfare agents, such as Bacillus anthracis, and also the capacity of neutralizing real chemical warfare agents, such as mustard gas or soman, by employing three different types of organic solutions enriched with ZnO, TiO2, and zeolite nanoparticles, specially designed for decontamination applications. The capacity of decontaminating BCWA was evaluated through specific investigation tools, including surface monitoring with the swabs method, minimum inhibitory (MIC) and minimum bactericidal concentration (MBC) evaluations, time-kill tests for microorganisms, and GC-MS for monitoring chemical agents on different types of surfaces (glass, painted metal, rubber, and cotton butyl rubber). These tests revealed high decontamination factors for BCWA even after only 10 min, accomplishing the requirements imposed by NATO standards. At the completion of the decontamination process, the formulations reached 100% efficacy for Bacillus anthracis after 10-15 min, for soman after 20-30 min, and for mustard gas in an interval comprised between 5 and 24 h depending on the type of surface analyzed.

RESUMEN

This paper comprises an extensive study on the evaluation of decontamination efficiency of three types of reactive organic suspensions (based on nanosized adsorbents) on two real chemical warfare agents: soman (GD) and sulfur mustard (HD). Three types of nanoparticles (ZnO, TiO2, and zeolite) were employed in the decontamination formulations, for enhancing the degradation of the toxic agents. The efficacy of each decontamination solution was investigated by means of GC-MS analysis, considering the initial concentration of toxic agent and the residual toxic concentration, measured at different time intervals, until the completion of the decontamination process. The conversion of the two chemical warfare agents (HD and GD) into their decontamination products was also monitored for 24 h.

RESUMEN

PURPOSE: To evaluate whether limited vitrectomy is as effective as complete vitrectomy in eyes with epiretinal membrane (ERM) and to compare the surgical times and rates of complications. METHODS: In this multicentre European study, data of eyes with ERM that underwent vitrectomy from January 2017 to July 2018 were analyzed retrospectively. In the limited vitrectomy group, a posterior vitreous detachment (PVD) was induced up till the equator as opposed to complete PVD induction till the vitreous base in the comparison group. Incidence of iatrogenic retinal breaks, retinal detachment, surgical time, and visual outcomes were compared between groups. RESULTS: We included 139 eyes in the analysis with a mean age being 72.2 ± 6.9 years. In this, sixty-five eyes (47%) underwent limited vitrectomy and 74 eyes (53%) underwent complete vitrectomy. Iatrogenic retinal tears were seen in both groups (5% in limited vitrectomy versus 7% in complete vitrectomy, p=0.49). Retinal detachment occurred in 2 eyes in the limited vitrectomy group (3%) compared to none in the complete vitrectomy group (p=0.22). Best-corrected visual acuity (BCVA) and central macular thickness improved significantly with no intergroup differences (p=0.18). Surgical time was significantly shorter in the limited vitrectomy group with 91% surgeries taking less than 1 hour compared to 71% in the complete vitrectomy group (p < 0.001). CONCLUSION: A limited vitrectomy is a time-efficient and effective surgical procedure for removal of epiretinal membrane with no additional complications.

RESUMEN

PURPOSE: To determine whether internal limiting membrane (ILM) peeling during pars plana vitrectomy for rhegmatogenous retinal detachment reduces the incidence of epiretinal membrane (ERM) formation. METHODS: In this retrospective study, preoperative, intraoperative, and postoperative data from all eyes undergoing pars plana vitrectomy for rhegmatogenous retinal detachment between January 2007 and December 2013 was analyzed. All cases with at least 1-year of follow-up were included. Data collection included vision, intraoperative complications, occurrence of ERM, and spectral domain optical coherence tomography characteristics. The OCTs were retrieved for all eyes and were graded by a single masked grader. RESULTS: Out of 159 eyes recruited, ILM peeling was done in 78 eyes (49%). Overall occurrence of ERM was 20%. Seven eyes (9%) in ILM peeling group and 25 eyes in the non-ILM peeling group (31%) showed ERM (P = 0.001). Postoperative vision was significantly better in eyes that had ILM peeling (0.48 ± 0.4 logarithm of the minimum angle of resolution [20/63] vs. 0.77 ± 0.6 logarithm of the minimum angle of resolution [20/125], P = 0.003). In multivariable models adjusting for type of tamponade, ILM peeling reduced the likelihood of ERM formation by 75% (P = 0.01). CONCLUSION: Internal limiting membrane peeling during pars plana vitrectomy for rhegmatogenous retinal detachment significantly reduces ERM formation in the postoperative period and is associated with better visual and anatomical outcomes.

Asunto(s)

RESUMEN

PURPOSE: To evaluate the efficacy of the modification of Adjustable Macular Buckling device in the treatment of myopic macular hole retinal detachment with posterior staphyloma. METHODS: Four consecutive patients suffering from myopic macular detachment with macular hole were treated using the macular buckling procedure. An Adjustable Macular Buckling device was used in all four cases and was modified using a 29-gauge optical fiber to illuminate its macular plate. RESULTS: Optical coherence tomography showed successful retinal reattachment and closure of the macular hole after the buckling procedure. The macular plate of the buckling device was properly positioned in all four patients. No complications were observed. CONCLUSION: The modification of the macular buckling device improves the accuracy of its positioning by illuminating its macular plate.

Asunto(s)

RESUMEN

BACKGROUND: The ideal intraocular lens in cases of aphakia without capsular support is debated. Choices include anterior chamber lenses, iris- or scleral-sutured lenses, and iris-claw lenses. Our aim was to report our long-term evaluation of the use of retropupillary implantation of the Artisan iris-claw intraocular lens (RPICIOL) in several aphakic conditions without capsular support. METHODS: A retrospective analysis of consecutive 320 eyes of 320 patients (222 males and 98 females) without capsular support in which we performed RPICIOL implantation in post-traumatic aphakia (141 eyes, group 1), post-cataract surgery aphakia (122 eyes, group 2), and in cases in which penetrating keratoplasty was associated with vitrectomy (57 eyes, group 3). Either anterior or posterior vitrectomy procedures were performed with 20-, 23-, or 25-gauge techniques for different associated anterior or posterior segment indications. We reviewed the refractive outcome, anatomical outcome, long-term stability of the implants, and possible long-term complications. RESULTS: The mean patient age was 59.7 years (range, 16-84 years) in group 1; 60.1 years (range, 14-76 years) in group 2; and 65.8 years (range, 25-71.5 years) in group 3. The mean follow-up time was 5.3 years (range, 1 month to 8 years). At the end of the follow-up period, the mean post-operative best-corrected LogMAR visual acuity was 0.6 (range, perception of light to 0.3) in group 1; 0.3 (range, 0.5-0.1) in group 2; and 0.6 (range, hand movement to 0.2) in group 3. Disenclavation of RPICIOLs occurred in three cases because of slippage of one of the iris-claw haptics and spontaneous complete posterior dislocation occurred in one case. One case presented with retinal detachment, and no cases of uveitis were observed. Eight cases complained of chronic dull pain, and severe iridodonesis was seen in five cases. One case of post-operative macular edema was observed without post-operative increase in the mean intraocular pressure. There was no statistically different change in the endothelial cell density (cells/mm(2)) at the end of the follow-up period. CONCLUSIONS: RPICIOL for secondary implantations is a valid alternative strategy to scleral-fixated or angle-supported IOL implantation.

Asunto(s)

RESUMEN

BACKGROUND: To evaluate the incidence of cystoid macular edema (CME) after 23-gauge pars plana vitrectomy (PPV) with or without combined cataract surgery for the treatment of idiopathic epiretinal membrane (ERM). METHODS: Retrospective, non-comparative, interventional case series. Data included patient age, indication for surgery, and intra- and post-operative complications. The follow-up lasted 1 year. Best-corrected visual acuity (BCVA logMAR), central foveal thickness (CFT micron-µ) and the incidence of intra-retinal cysts were evaluated. CME was defined as post-operative observation of intra-retinal cysts at optical coherence tomography, preventing improvement or causing reduction of BCVA when compared to the pre-operative value. Statistical analysis was performed to identify the risk factors of CME. RESULTS: Two hundred and forty two eyes of 242 patients underwent PPV for the treatment of idiopathic ERM. Statistical analysis showed that the presence of preoperative intra-retinal cysts were associated with persistent CME following surgery (odds ratio 3.89; 95%CI: 1.63-9.28, P = 0.0004). However, postoperative CME occurred in 10 % of eyes that did not show preoperative CME. In addition, there was a significant correlation between the baseline value of CFT and the values of CFT at each time point during the follow up (p < 0.0001), with greater values of the pre-operative thickness correlating to greater values of post-operative thickness. CONCLUSIONS: Persistent or new CME following surgery for idiopathic ERM are frequently identified after PPV for ERM. The statistical results of the current study suggest that intraretinal cysts and increased preoperative CFT are associated with reduced visual acuity after surgery.

Asunto(s)

RESUMEN

PURPOSE: To report successful treatment of refractive glaucoma in a patient submitted to osteo-odonto-keratoprosthesis surgery for Stevens-Johnson syndrome. METHODS: An interventional case report. RESULTS: The patient is a 62-year-old Indian man with known Stevens-Johnson syndrome since 1972 secondary to tetracycline therapy, with bilateral dry eye and corneal blindness. He underwent symblepharon release surgery with mucous membrane graft in both eyes. Osteo-odonto-keratoprosthesis surgery was later performed on the left eye. He was submitted to 2 Ahmed valve implants to control secondary glaucoma but visual fields continued to worsen; hence, he underwent endoscopic 140° cyclophotocoagulation with a good control of IOP. CONCLUSION: Endoscopic cyclophotocoagulation as alternative treatment provides good results in refractory glaucoma after osteo-odonto-keratoprosthesis surgery.

Asunto(s)

RESUMEN

A 79-year-old hyperglycemic patient was referred to the 'Santa Maria delle Croci' Hospital, Ravenna, Italy. He presented with visual impairment in the right eye. Four years ago, he had had an uneventful cataract surgery in the right eye. We observed an opacification of the intraocular lens (IOL) causing significant visual disturbance. The IOL was exchanged. Unfortunately, pathologic analysis was not performed. Patient-related factors such as hyperglycemia and hypertension might have been responsible for the opacification. To our knowledge, there is only one previous report of opacification of the Akreos Adapt AO IOL.

RESUMEN

BACKGROUND: Combined post-traumatic aniridia and aphakia demand extensive and complex reconstructive surgery. We present our approach for simultaneous correction of this surgical situation with the use of the ArtificialIris (Dr. Schmidt Intraocularlinsen GmbH, Germany) with a foldable acrylic IOL Lentis L-313 (Oculentis, GmbH, Germany) sutured to its surface. The novelty (our first operation was on June 2010) of this surgical technique is based on the combined use of foldable (with closed haptics) IOL and Artificialiris to correct post-traumatic aniridia and aphakia. METHODS: Four consecutive cases of combined post-traumatic lesions of iris and lens, corrected with complex device ArtificialIris and foldable IOL. In two cases, the compound implant was sutured to the sclera in sulcus during the penetrating keratoplasty; in another case, it was positioned through a corneal incision of about 5.0 mm with transscleral fixation, and in one patient with preserved capsular support and possibility of IOL in-the-bag implantation the ArtificialIris was placed in sulcus sutureless through a clear corneal tunnel. RESULTS: Maximal follow-up was 6 months. The complex device was placed firmly fixed within the sulcus, including in the eye implanted without sutures, and showed a stable and centered position without any tilt or torque. CONCLUSION: Management of post-traumatic aniridia combined with aphakia by haptic fixation of a foldable acrylic IOL on a foldable iris prosthesis appears to be a promising approach which gives the surgeon the possibility to correct a complex lesion with one procedure, which is less traumatic and faster. Existence of foldable materials, both iris and IOL, permits relatively small corneal incisions (4.0-5.0 mm). Moreover, the custom-tailored iris prosthesis gives a perfect aesthetic result.

Asunto(s)