Intracameral Injection in Rats with Low Risk of Adverse Effects.

Intracameral injection is a standard administration routine in ophthalmology. The application of intracameral injection in rodents for research is challenging due to the limiting dimensions and anatomy of the eye, including the small aqueous humor volume, the lens curvature, and lens thickness. Potential damage during intracameral injections introduces adverse effects and experimental variability. This protocol describes a procedure for intracameral injection in rats, allowing precision and reproducibility. Sprague-Dawley rats were used as experimental models. Since the lens position in rats protrudes into the anterior chamber, injecting from the periphery, as done in humans, is unfavorable. Therefore, an incision is created in the central corneal region using a 31 gauge 0.8 mm stiletto blade to form a self-sealing tunnel into the anterior chamber. An incision at an angle close to the flat allows to create a long tunnel, which minimizes the loss of aqueous humor and shallowing of the anterior chamber. A 34 gauge nanoneedle is inserted into the tunnel for injection. This enables penetration with minimal friction resistance and avoids touching the lens. Injection of trypan-blue allows visualization by slit microscopy the presence of the dye in the anterior chamber and exclude leakage. Bioavailability to the corneal endothelial layer is demonstrated by injection of Hoechst dye, which stained the nuclei of corneal endothelial cells after injection. In conclusion, this protocol implements a procedure for accurate intracameral injection in rats. This procedure may be used for intracameral delivery of various drugs and compounds in experimental rat models, increasing the efficiency and reproducibility of ophthalmic research.

Use of recombinant tissue plasminogen activator (rTPA) for treatment of fibrin in the anterior chamber of the horse.

BACKGROUND: Recombinant intracameral tissue plasminogen activator (rTPA) administration can aid clearance of fibrin from the anterior chamber. MATERIALS AND METHODS: In this retrospective multicentre case series, the effect of intracameral rTPA administration to treat fibrin in the anterior chamber resulting from trauma or inflammatory ocular disease was evaluated. Clinical data from 30 treatments in 29 horses were obtained from medical records from 2003 to 2022. Association between time from onset of clinical signs and time for rTPA treatment to effect was studied with regression analysis. RESULTS: Twenty-seven horses (93.1%) had no previous history of ophthalmic disease; one had an iridic cyst, and another had equine recurrent uveitis. The majority of cases were related to trauma (79.3%). Median time from the onset of clinical signs to treatment was 12 h (IQR = 4-48 h). rTPA (72% 20 µg; 24% 25 µg; 3.3% 40 µg) was administered once in all but one eye, which was treated twice. Resolution of fibrin was seen in 96.9% (29/30) of treatments. Fibrin accumulation recurred in one case but resolved 14 days after the second treatment. Complications were seen in four treatments (13.3%): moderate pain for 24 h, intracameral debris and mild intracameral haemorrhage in a horse that received 40 µg of tissue plasminogen activator. Recurrence of fibrin accumulation was absent in 96.7% of cases. Median time to effect was 20 min (IQR = 10-45 min). Time for rTPA treatment to effect was not associated with time from fibrin formation (R2 = 0.09; p = 0.11). CONCLUSION: Intracameral rTPA treatment can be considered at 20-25 µg in 0.1 mL solution to aid resolution of fibrin accumulation.

Changes in ocular biometrics following cycloplegic refraction in strabismic and amblyopic children.

This study was aimed to analyze ocular biometric changes following cycloplegia in pediatric patients with strabismus and amblyopia. Cycloplegia is routinely used to measure refractive error accurately by paralyzing accommodation. However, effects on axial length (AL), anterior chamber depth (ACD), keratometry (Km), and white-to-white distance (WTW) are not well studied in this population. This retrospective study examined 797 patients (1566 eyes) undergoing cycloplegic refraction at a Samsung Kangbuk hospital pediatric ophthalmology clinic from 2010 to 2023. Ocular biometry was measured before and after instilling 1% cyclopentolate and 0.5% phenylephrine/0.5% tropicamide. Patients were categorized by strabismus diagnosis, age, refractive error and amblyopia status. Differences in AL, ACD, Km, WTW, and refractive error pre- and post-cycloplegia were analyzed using paired t tests. ACD (3.44 ±â€…0.33 vs 3.58 ±â€…0.29 mm, P < .05) and WTW (12.09 ±â€…0.42 vs 12.30 ±â€…0.60 mm, P < .05) increased significantly after cycloplegia in all groups except other strabismus subgroup (Cs) in both parameters and youngest subgroup (G1) in ACD. Refractive error demonstrated a hyperopic shift from -0.48 ±â€…3.00 D to -0.06 ±â€…3.32 D (P < .05) in overall and a myopic shift from -6.97 ±â€…4.27 to -8.10 ±â€…2.26 in high myopia (HM). Also, AL and Km did not change significantly. In conclusion, cycloplegia impacts ocular biometrics in children with strabismus and amblyopia, significantly increasing ACD and WTW. Refractive error shifts hyperopically in esotropia subgroup (ET) and myopically in high myopia subgroup (HM), eldest subgroup (G3) relating more to anterior segment changes than AL/Km. Understanding cycloplegic effects on biometry is important for optimizing refractive correction in these patients.

Iris atrophy following intracameral dexamethasone injection: a report of two pediatric cases.

We report 2 pediatric cases of iris atrophy that developed roughly 1 month after intracameral injection of dexamethasone suspension 9% following unilateral goniotomy and cataract extraction.

Cataract surgery in children using intracameral mydriatic.

PURPOSE: To study the pupil dynamics with premixed intracameral anesthetic mydriatic combination of phenylephrine (0.31%), tropicamide (0.02%), and lidocaine (1%) in pediatric cataract surgery. METHODS: Consecutive children aged ≤12 years planned for cataract surgery were recruited. A commercially available premixed combination of phenylephrine (0.31%), tropicamide (0.02%), and lidocaine (1%) was injected at the beginning of surgery without any topical/infusion drugs for mydriasis. Pupil sizes at various points of surgery were studied. RESULTS: We recruited 75 patients with a mean age of 24.3 ± 33.4 months (range: 1 month-11 years). Adequate mydriasis with a single injection was achieved in 93.5% (n = 73 eyes of 70 patients) without additional pharmacotherapy or intervention. The mean pupillary diameter increased from 1.8 ± 0.79 to 6.1 ± 1.4 mm after injection (mean change of 4.2 ± 1.25 mm from baseline). The mean variability in pupillary diameter was 0.73 ± 1.3 mm. In five eyes, good dilatation was not possible even after repeat injection. CONCLUSION: Fixed-dose premixed intracameral injection is effective in pupil dilatation. It alleviates the need for any topical dilators or additional intraoperative supplementation for pediatric cataract surgery.

Novel Technique for Descemetorhexis Under Ophthalmic Viscosurgical Devices and Air.

PURPOSE: The aim of this study was to describe a novel technique for descemetorhexis that combines the advantages of stable anterior chamber (AC) associated with ophthalmic viscosurgical devices and optimal surgical visualization seen with air to overcome the issues of poor Descemet membrane (DM) visibility or AC instability when each is used alone. METHODS: This study is a description of a new surgical approach. RESULTS: We describe a new technique for performing descemetorhexis. The simultaneous presence of cohesive ophthalmic viscosurgical device and air in the AC offers optimal DM visualization and guarantees a stable AC during this surgical step. It does not require an additional incision for an AC maintainer. CONCLUSIONS: The described technique may facilitate the surgical step of descemetorhexis, offering improved AC stability and better visualization of the DM. It may reduce early postoperative graft detachment due to the presence of residues of the recipient's diseased DM.

Advances in Understanding the Mechanism of Ophthalmic Viscosurgical Device Retention in the Anterior Chamber or on the Corneal Surface during Ocular Surgery.

Retention durability, especially in the eye, is one of the most important properties of ophthalmic viscosurgical devices (OVDs) during ocular surgery. However, the information on the physical properties of OVDs is insufficient to explain their retention durability. The purpose of this study is to clarify the mechanism of OVD retention to improve understanding of the behavior of OVDs during ocular surgery. To elucidate the mechanism of OVD retention, we have developed a new test method for measuring repulsive force. As a result, the maximum repulsive force of OVDs was positively and well correlated with the retention durability of investigated OVDs. Consequently, we demonstrated that the repulsive force could be used as an index of retention durability on the ocular surface and in the eye. We directly compared the intraocular retention durability of three OVDs (Shellgan, Viscoat, and Opegan-Hi) in ex vivo porcine eyes. Opegan-Hi was immediately removed from the anterior chamber, but Shellgan and Viscoat remained largely in the anterior chamber as determined by fluorescence imaging. These results showed that the intraocular retention behavior of OVDs was similar to their ocular surface behavior in our previous report, suggesting that retention durability is dependent on the OVD itself. The retention durability of Shellgan seemed to be higher than that of Viscoat, and the maximum repulsive force of Shellgan was 1.35-fold higher than that of Viscoat. Therefore, the repulsive force might be a useful index for assessing the difference in the retention durability between OVDs such as Shellgan and Viscoat.

Treatment of cytomegalovirus anterior segment infection with intravitreal injection of ganciclovir in adjunction with or without oral valganciclovir: a long-term results.

We evaluated the therapeutic outcome of intravitreal injection (IVI) of ganciclovir with/without oral valganciclovir for cytomegalovirus (CMV) anterior segment infection. We enrolled 61 patients (61 eyes) with PCR-proven CMV anterior segment infection. IVI of ganciclovir (2 mg/0.05 mL) was given as a loading dose; subsequent use of oral valganciclovir (900 mg twice daily) was determined according to the severity of anterior chamber inflammation after injection. All eyes had IVI of ganciclovir, and 53 patients received oral valganciclovir as adjunctive therapy with a mean duration of 1.9 months to achieve disease remission. Repeated diagnostic aqueous taps were performed in 37 eyes with suspected recurrence, and CMV DNA was positive in 24 eyes. This therapeutic strategy afforded a median 50% recurrence-free survival time of 47.0 ± 8.12 months. The patients' mean best corrected visual acuity, intraocular pressure and corneal endothelial cell counts stabilized or improved. Corneal transplantation before CMV infection diagnosis was identified as an independent risk factor for recurrence (hazard ratio 6.81, 95% confidence interval 1.21-38.23, P = 0.029). In patients with CMV anterior segment infection, the relative short-term therapeutic strategy, IVI of ganciclovir in adjunction with/without oral valganciclovir, effectively achieved a median recurrence-free survival time of nearly 4 years.

Endophthalmitis Prophylaxis Failures in Patients Injected With Intracameral Antibiotic During Cataract Surgery.

PURPOSE: To estimate the association of cefuroxime and moxifloxacin in relation to the occurrence of endophthalmitis following phacoemulsification cataract surgery. DESIGN: Retrospective clinical cohort study. METHODS: We studied patients with noncomplex phacoemulsification cataract surgery in Kaiser Permanente Northern California during 2014-2019. Data were obtained for acute, postoperative endophthalmitis within 90 days of phacoemulsification, including culture and antibiogram results, intracameral and topical antibiotic agent, and dose. In a post hoc analysis, we also examined preoperative anterior chamber depth (ACD) and postoperative anterior chamber volume (ACV). RESULTS: Of 216,141 surgeries, endophthalmitis occurred in 0.020% of moxifloxacin-injected eyes and 0.013% of cefuroxime eyes (relative risk 1.62 with 95% CI 0.82-3.20, P = .16). Of the 34 (0.016%) cases of endophthalmitis, cefuroxime 1 mg was injected into 13 eyes and moxifloxacin 0.1% into 21 eyes. Organisms with antibiograms were identified in 12 (35%) cases. Of these, bacteria recovered from cefuroxime-injected eyes were resistant to cefuroxime in all cases (4/4), with Enterococcus comprising half of these. In eyes injected with moxifloxacin 0.1%, 6 out of 7 organisms were sensitive to moxifloxacin injected with 0.1 mL and in 1 eye injected with 1 mL. Streptococcus was the most common organism recovered (6/9) in moxifloxacin-injected eyes. Preoperative ACD and postoperative calculated ACV were higher in eyes injected with moxifloxacin. CONCLUSIONS: Endophthalmitis cases with positive cultures were generally related to organism resistance in cefuroxime eyes but to sensitive organisms in moxifloxacin eyes. Moxifloxacin doses may have been insufficient in eyes with larger ACV.

Effect of Intracameral Cefuroxime on Graft Endothelial Cells in Descemet Membrane Endothelial Keratoplasty: A Comparative Study.

Purpose: To evaluate the effect of intracameral cefuroxime on graft endothelial cell loss after simple Descemet Membrane Endothelial Keratoplasty (DMEK) and combined DMEK and cataract surgery.Materials and Methods: Single-center retrospective comparative analysis. One hundred and three patients were included, 31 in the cefuroxime group and 72 in the non-cefuroxime (NC) group. Best Spectacle-Corrected Visual Acuity (BSCVA), endothelial cell density (ECD) of the graft measured by specular microscopy, and the recipient's pachymetry were recorded pre-operatively and at 1, 3, and 6 months after surgery.Results: In the cefuroxime group, BSCVA was 0.22 ± 0.27 LogMAR, 0.15 ± 0.24 LogMAR and 0.07 ± 0.22, respectively, at 1, 3, and 6 months after surgery with no significant differences found when compared to the NC group (p > .05). Anatomical outcomes were similar as mean pachymetry decreased from 599 ± 51 µm preoperatively to 511 ± 30 µm at 6 months after surgery in the cefuroxime group and from 607 ± 67 µm preoperatively to 519 ± 32 µm at 6 months in the NC group (p = .25). Endothelial cell loss was comparable between both groups: 33.4% versus 33.6% at 1 month (p = .97), 37.4% versus 34.9% at 3 months (p = .68) and 41.6% versus 38.3% at 6 months (p = .42) in the cefuroxime and NC groups, respectively. The rates of rebubbling, graft rejection, and cystoid macular edema were not significantly higher in the cefuroxime group.Conclusion: The use of intracameral cefuroxime during simple or combined DMEK did not lead to higher graft endothelial cell loss.

Anterior Uveitis Due to Intracameral Moxifloxacin: A Case Report.

Purpose: To report a case of a drug-induced anterior uveitis secondary to the use ofintracameral moxifloxacin.Case report: A 64-year-old Colombian male patient presented with severe ocular pain and photophobia in his left eye 15 days after cataract surgery. In the ophthalmology and glaucoma specialist evaluation, pigment dispersion in the anterior chamber and camerular angle, severe anterior segment inflammation, and elevated intraocular pressure were observed. Poor response to treatment for a suspected viral origin and exclusion of other possible etiologies, led to the conclusion of intracameral moxifloxacin induced anterior uveitis.Conclusion and importance: We present the second published case worldwide about anterior uveitis secondary to intracameral moxifloxacin, which may rarely cause hypertensive uveitis that may be confused with viral uveitis. This provides evidence on the importance of postoperative follow-up by the surgeon for an early referral and treatment of these cases.

Traumatic hyphema in a patient with severe hemophilia A: Clinical features and management.

PURPOSE: To describe a case of traumatic hyphema in a patient with severe hemophilia A. CASE: We present a case of a 16-year-old boy with severe hemophilia A who presented to our ophthalmology department with total hyphema and elevated intraocular pressure 3 days after a history of blunt ocular trauma on his right eye. Due to the persistent intraocular pressure elevation and total hyphema despite medical intervention, an early anterior chamber washout was performed with the replacement of factor VIII preoperatively and postoperatively. Re-bleeding or any other complications were not experienced during surgery or postoperatively. At the first postoperative week, 20/20 visual acuity and a normal intraocular pressure without antiglaucoma medication was retained and remained stable during the 6-month follow-up. CONCLUSION: In such cases with hemophilia A, traumatic hyphema, and intraocular pressure elevation despite medical intervention, an early surgical clot removal under intense factor VIII replacement could be performed. In the early postoperative period, factor replacement should be resumed in order to avoid re-bleeding.

SHP-1 suppresses endotoxin-induced uveitis by inhibiting the TAK1/JNK pathway.

We investigated how Src-homology 2-domain phosphatase-1 (SHP-1) regulates the inflammatory response in endotoxin-induced uveitis (EIU), and the signalling pathways involved. One week after intravitreal injection of short hairpin RNA targeting SHP-1 or SHP-1 overexpression lentivirus in rats, we induced ocular inflammation with an intravitreal injection of lipopolysaccharide (LPS). We then assessed the extent of inflammation and performed full-field electroretinography. The concentrations and retinal expression of various inflammatory mediators were examined with enzyme-linked immunosorbent assays and Western blotting, respectively. SHP-1 overexpression and knockdown were induced in Müller cells to study the role of SHP-1 in the LPS-induced inflammatory response in vitro. Retinal SHP-1 expression was up-regulated by LPS. SHP-1 knockdown exacerbated LPS-induced retinal dysfunction and increased the levels of proinflammatory mediators in the retina, which was abrogated by a c-Jun N-terminal kinase (JNK) inhibitor (SP600125). SHP-1 overexpression had the opposite effects. In Müller cells, the LPS-induced inflammatory response was enhanced by SHP-1 knockdown and suppressed by SHP-1 overexpression. SHP-1 negatively regulated the activation of the transforming growth factor-ß-activated kinase-1 (TAK1)/JNK pathway, but not the nuclear factor-κB pathway. These results indicate that SHP-1 represses EIU, at least in part, by inhibiting the TAK1/JNK pathway and suggest that SHP-1 is a potential therapeutic target for uveitis.

Endogenous Endophthalmitis Caused by Isolated Listeria Monocytogenes Infection.

Purpose: The purpose of this report is to present an extremely rare case of endogenous Listeria monocytogenes endophthalmitis.Methods: A 72-year-old woman was diagnosed with endogenous endophthalmitis. Listeria monocytogenes was identified by culture of aqueous humor. Multiple investigations could not reveal any source of infection. An overview of other published cases is presented and a standardized treatment protocol is suggested.Results: Treatment consisted of topical therapy with antibiotics, corticosteroids, cycloplegics, and intraocular pressure-lowering agents, four intravitreal injections of vancomycin, an anterior chamber washout, intravenous amoxicillin, and eventually a pars plana vitrectomy. The inflammation subsided and the patient was discharged with a best-corrected visual acuity of 20/40.Conclusion: Our study emphasizes the importance of adequate microbiological testing and initiating appropriate treatment early in the management of endogenous endophthalmitis.

The effect of orally administered glycerol on anterior chamber depth during cataract surgery in eyes with narrow anterior chambers.

PURPOSE: Cataract surgery on eyes with shallow anterior chambers may be demanding. Glycerol intake prior to surgery has been a well-known method in an effort to increase anterior chamber depth. It is used since it is thought that glycerol as an osmotic agent causes the vitreous body to shrink, pulling back the iris and thereby deepening the anterior chamber - making the surgery easier. Our controlled clinical trial tests this hypothesis and investigates the effect of glycerol on anterior chamber depth (ACD), intraocular pressure (IOP), corneal thickness (CCT), pupil diameter change after viscodilation (PD), operating time and perioperative complications. METHODS: We performed a controlled clinical trial. All patients underwent cataract surgery on both eyes with at least 7 days apart. Preoperatively the patient was given glycerol orally when the right eye was operated - when the left eye was operated, nothing was given. In this way, each patient was serving as its own control. Measurements of ACD, IOP and CCT were performed before and after glycerol intake, pupillary diameter was measured before and after viscoelastics during the operation, and operating time and surgical complications were noted. RESULTS: The study included 22 patients with bilateral cataract and anterior chambers depth <2.5 mm. Glycerol caused the anterior chamber to increase by 0.022 mm (p < 0.05), and IOP was lowered by 5.1 mmHg compared to the control group (p < 0.05). However, exposure to glycerol showed no effect on CCT, pupillary dilation of viscoelastics, operating time or surgical complications. CONCLUSION: Glycerol increases anterior chamber depth and lowers intraocular pressure significantly. These changes had no significant impact on operating time nor on the complication rate, suggesting that these changes are too subtle to have a clinical impact on the cataract procedure.

Vault changes after cyclopentolate instillation in eyes with posterior chamber phakic intraocular lens.

Posterior chamber phakic intraocular lens (pIOL) implantation is a common option for correcting moderate-to-high ocular refractive defects. Because this pIOL is implanted on ciliary sulcus, the distance between the back surface of the pIOL and the anterior surface of the crystalline lens, that it is known as vault, should be measured in different conditions to ensure the technique's safety. Cyclopentolate is a drug that dilates the pupil and relaxes accommodation (cycloplegia). It is often used for different ocular examinations and for other medical purposes. However, there is no evidence of the effect of this drug on vault. This study quantified central vault changes associated with cyclopentolate instillation. We measured the vault under normal conditions (pre-cycloplegic instillation) and after instilling cyclopentolate on 39 eyes of 39 patients with implanted pIOL. Our results suggest that cyclopentolate instillation may induce changes to vault in eyes with implanted pIOL. These changes seem safe and are mainly associated with vault under normal conditions, but also with anterior chamber depth, pupillary diameter and pIOL size.

Outcomes of Ahmed Glaucoma Valve Implantation With Viscoelastic Fill at Both Beginning and End of Surgery.

PRéCIS:: Intracameral injection of viscoelastic at the beginning of Ahmed FP7 implantation did not reduce early postoperative complication rates. PURPOSE: To evaluate early postoperative complication rates after a modified technique in which the anterior chamber (AC) is filled with viscoelastic at the beginning of Ahmed FP7 implantation before conjunctival peritomy. SUBJECTS AND METHODS: A retrospective chart review was performed of eyes that underwent Ahmed FP7 implantation with or without viscoelastic fill to ~20 mm Hg by finger tension by a single surgeon (M.R.M). Viscoelastic prevented the AC from becoming shallow at any time during surgery, and additional viscoelastic was injected into the AC at the end of surgery to achieve a final intraocular pressure (IOP) of 20 mm Hg. RESULTS: A total of 159 eyes of 159 patients were included. Mean age was 76.4±10.4 years. Mean preoperative IOP was 30.3±9.7 mm Hg on 2.7±1.2 glaucoma medications. On postoperative day 1, there was an IOP spike ≥30 mm Hg in 0% of patients. Within the first postoperative month, hypotony (<5 mm Hg) occurred in 19 (21.8%) eyes that received viscoelastic fill compared with 5 (13.2%) eyes that did not receive viscoelastic fill (P=0.26). During the early postoperative period (≤3 mo), there was no difference in AC depth, microhyphema, choroidal effusion, or leakage between the 2 groups (P≥0.30 for all). There was a higher rate of layered hyphemas in the viscoelastic-fill group at postoperative week 1 (P=0.01). At 3-month follow-up, mean IOP was 14.9±5.5 mm Hg on 1.6±0.8 medications in the viscoelastic-fill group and 16.0±5.2 mm Hg on 1.0±1.2 medications in the nonviscoelastic-fill group (IOP P=0.35). Compared with baseline, change in IOP at 3 months was similar between both groups (P=0.15). Rates of additional medications and procedures did not differ between the 2 groups at any postoperative visit. CONCLUSIONS: Early intracameral injection of viscoelastic during Ahmed glaucoma valve implantation did not reduce early postoperative complication rates.

Pupil expansion device use and operative outcomes with topical dilation vs intracameral epinephrine in resident-performed cataract surgery.

PURPOSE: To compare the use of topical dilation drops vs topical drops with the addition of intracameral epinephrine in resident-performed cataract surgery and the effects on pupil expansion device (PED) use, surgical costs, and surgical times. SETTING: Iowa City Veterans Affairs Medical Center, Iowa City, Iowa, USA. DESIGN: Retrospective chart review. METHODS: Resident-performed primary cataract surgical cases using topical dilation drops only or drops with the addition of intracameral epinephrine were analyzed for PED use, surgical time, and costs in all patients and in patients with a history of tamsulosin use. RESULTS: In the topical group, PEDs were used in 31.1% of cases compared with 13.5% of cases in the intracameral group (P < .0001). History of tamsulosin use was noted in about one third of cases in both groups. For patients with a history of tamsulosin use, PED use decreased from 52.7% in the topical cases to 17.9% in the intracameral group (P < .0001). Surgical times were on average 7.1 minutes slower with PED use than without PED use. There was a medication savings of $50.44 USD per case in the intracameral group compared with the topical group. Factoring in the $100 to $130 USD per PED used, total surgical costs were $19 267 USD less in the intracameral group over 6 months. CONCLUSIONS: Intracameral epinephrine with lidocaine decreases the need for PED use during cataract surgery, lowers intraoperative costs, and improves efficiency compared with topical dilation drops alone.