Three-Dimensional Ultrasound Imaging of Retinoblastoma and Its Correlation With Pathology.

BACKGROUND AND OBJECTIVE: Monitoring the response of retinoblastoma to globe-salvaging therapies is based on subjective assessments of changes determined by fundoscopy, ultrasound, and optical coherence tomography. Advances in organ-preserving therapies have increased the need for objective, quantitative estimates of tumor response to treatment. Primary tumor volume is a metric that can be objectively determined as a surrogate measure of treatment response. PATIENTS AND METHODS: We evaluated the correlation of objective, quantitative estimates of tumor volume made with two-dimensional (2D) and three-dimensional (3D) ultrasound with gold standard pathological tumor volumes derived by analysis of enucleation specimens. RESULTS: Twelve eyes in 12 patients undergoing primary enucleation were evaluated by 2D and 3D ultrasound during ophthalmic examination under anesthesia prior to enucleation. 2D- and 3D-ultra-sound measurements of tumor volume were both strongly correlated with pathological estimates of tumor volume (r = 0.69, P = 0.018; and r = 0.66, P = 0.027, respectively). CONCLUSIONS: 2D- and 3D-ultrasound measurements of retinoblastoma primary tumor volume are highly correlated with pathological estimates. 3D measurements are easy to perform with volumetric probes and consider the irregular morphology of the tumor. Further study should be undertaken to evaluate the performance of these metrics as surrogate markers of tumor response to treatment. [Ophthalmic Surg Lasers Imaging Retina 2024;55:136-140.].

Charcot-Marie-Tooth Disease and Implications on Corneal Refractive Surgery.

Charcot-Marie-Tooth (CMT) disease is the most common inherited polyneuropathy, with a characteristic phenotype of distal muscle weakness, atrophy, and sensory loss. Variable ocular involvement has been documented in patients with CMT, with optic atrophy as the most frequently reported symptom. Although the Charcot-Marie-Tooth Association has generally deemed laser-assisted in situ keratomileuses (LASIK) a safe option for patients with CMT, reports of corneal refractive surgery are lacking in this patient population. This commentary discusses the current understanding of CMT, including its ocular manifestations, and additional specific testing to consider when evaluating these patients for corneal refractive surgery.

Cataract extraction after inadvertent Nd:YAG laser capsulotomy in a phakic eye.

Inadvertent neodymium: yttrium-aluminum-garnet (Nd:YAG) capsulotomies are rare, with only one incident reported in the literature prior to the present case. We discuss the management of a phakic patient with a dense posterior subcapsular cataract who underwent yttrium-aluminum-garnet (YAG) capsulotomy for presumed posterior capsular opacification. Operative course involved cataract surgery with anterior vitrectomy for prolapsed lens fragments due to the disrupted posterior capsule. This patient experienced excellent visual outcomes postoperatively, with ultimate best-corrected visual acuity of 20/20. This case underscores the importance of thorough preoperative time out, including confirmation of patient's understanding of the intended procedure.

Implications of Corneal Refractive Surgery in Patients with Fabry Disease.

Fabry disease is an X-linked lysosomal storage disorder involving abnormal metabolism of glycosphingolipids, resulting in a range of multisystem organ dysfunction and ocular manifestations. Reports of laser-assisted in situ keratomileuses (LASIK) and photorefractive keratectomy (PRK) are lacking in this patient population. Proceeding with corneal refractive surgery in patients with Fabry disease raises concerns regarding the pre-existing corneal manifestations, reduced mesopic visual acuity, the potential for conjunctival lymphangiectasia, and predisposition to dry eye syndrome. This commentary discusses the current understanding of Fabry disease, including its ocular manifestations, and explores factors to consider when evaluating these patients for LASIK or PRK.

Comparison of 6.0 mm versus 6.5 mm Optical Zone on Visual Outcomes after LASIK.

Previous studies have demonstrated safety and efficacy using 6.0 and 6.5 mm optical zones in the WaveLight EX500 Excimer Laser System but have not evaluated if differing optical zone sizes influence refractive outcomes. This study examines visual outcomes between two study populations undergoing LASIK with either a 6.0 mm (1332 patients) or 6.5 mm (1332 patients) optical zone. Outcomes were further stratified by severity of myopia (low, moderate, and high) and astigmatism (low and high). Patients were matched by age and preoperative manifest sphere and cylinder. Postoperative measurements were then compared. The 6.5 mm group demonstrated better postoperative manifest refractive spherical equivalent (MRSE), manifest sphere, and absolute value of the difference in actual and target spherical equivalent refraction (|∆ SEQ|), within the total population, moderate myopia, and low astigmatism groups, but this did not lead to improved postoperative uncorrected distance visual acuity (UDVA) or best corrected distance visual acuity (CDVA). Though astigmatic correction and postoperative angle of error were similar between optical zone sizes, they were significantly worse with high myopia. Overall, this study demonstrates differences in visual outcomes between the 6.0 and 6.5 mm optical zone sizes that may warrant consideration; however, essentially, the results are comparable between them.

Ectasia After Corneal Refractive Surgery: A Systematic Review.

INTRODUCTION: The incidence of ectasia following refractive surgery is unclear. This review sought to determine the worldwide rates of ectasia after photorefractive keratectomy (PRK), laser-assisted in situ keratomileusis (LASIK), and small incision lenticule extraction (SMILE) based on reports in the literature. METHODS: A systematic review was conducted according to modified Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Publications were identified by a search of eight electronic databases for relevant terms between 1984 and 2021. Patient characteristics and preoperative values including manifest refractive spherical refractive equivalent (MRSE), central corneal thickness (CCT), anterior keratometry, postoperative residual stromal bed (RSB), and percent tissue altered (PTA) were summarized. In addition, annual rates of each refractive surgery were determined, and incidence of post-refractive ectasia for each type was calculated using the number of ectatic eyes identified in the literature. RESULTS: In total, 57 eyes (70 eyes including those with preoperative risk factors for ectasia) were identified to have post-PRK ectasia, while 1453 eyes (1681 eyes including risk factors) had post-LASIK ectasia, and 11 eyes (19 eyes including risk factors) had post-SMILE ectasia. Cases of refractive surgery performed annually were estimated as 283,920 for PRK, 1,608,880 for LASIK, and 96,750 for SMILE. Reported post-refractive ectasia in eyes without preoperative identifiable risk factors occurred with the following incidences: 20 per 100,000 eyes in PRK, 90 per 100,000 eyes in LASIK, and 11 per 100,000 eyes in SMILE. The rate of ectasia in LASIK was found to be 4.5 times higher than that of PRK. CONCLUSION: Post-refractive ectasia occurs at lower rates in eyes undergoing PRK than LASIK. Although SMILE appears to have the lowest rate of ectasia, the number of cases already reported since its recent approval suggests that post-SMILE ectasia may become a concern. Considering that keratoconus is a spectrum of disease, pre-existing keratoconus may play a larger role in postoperative ectasia than previously accounted for in the literature.

Toric Implantable Collamer Lens for the Treatment of Myopic Astigmatism.

PURPOSE: To report visual outcomes following surgical correction of myopic astigmatism with Visian Toric implantable collamer lens (ICL) (STAAR Surgical, Monrovia, CA, USA) at a single tertiary refractive center in the United States. PATIENTS AND METHODS: Toric ICL was implanted in 96 eyes (55 patients) with mean preoperative sphere of -8.98 ± 3.04 diopters (D) and cylinder of -2.67 ± 1.02 D from December 2018 to February 2021. Primary visual outcomes of efficacy, safety, stability, predictability of refractive correction, and astigmatic analysis were reported at three and twelve months postoperatively. Secondary subjective outcomes included patient-reported dry eye symptoms and glare/halos at postoperative visits. Other secondary outcomes were biometric data and postoperative vault over time. RESULTS: At three and twelve months, 75 and 46 eyes were evaluated, respectively. At twelve months, the mean manifest refraction spherical equivalent (MRSE) was -0.23 ± 0.47 D with 93% achieving within ±1.00 D of target refraction. The manifest refractive cylinder (MRC) at twelve months was -0.73 ± 0.51 D, with 86% within ±1.00 D of target. Uncorrected distance visual acuity (UDVA) was 20/20 or better in 74% of eyes at twelve months. No patients lost ≥2 lines of corrected distance visual acuity (CDVA) at twelve months. The mean angle of error was -0.9 ± 10.2° at three months and -1.6 ± 12.8° at twelve months. One patient required bilateral lens rotation, four patients underwent secondary enhancement with LASIK/PRK, and seven patients underwent postoperative limbal relaxing incisions. CONCLUSION: This initial single-site experience finds Toric ICL implantation for myopic astigmatism to be safe and effective. Patients can achieve markedly improved UDVA in a single surgery with stable vision over time and minimal adverse subjective symptoms.

Intraocular Acrylic Allergy: Is it Something to Sneeze at?

Cataract surgery is most commonly performed with acrylic intraocular lens (IOL) implantation. To date, there have been no reported cases of intraocular acrylic allergy despite increasing rates of acrylic-induced contact dermatitis elsewhere in the body. Concern regarding acrylate sensitization is gaining traction in the ophthalmology community. This commentary explores the lack of intraocular atopy and whether an acrylic allergy necessitates extensive preoperative consideration.

Clearing the Haze: Navigating Corneal Refractive Surgery in Patients with Posterior Polymorphous Corneal Dystrophy.

Posterior polymorphous corneal dystrophy (PPCD) is a corneal disorder of the endothelium and Descemet's membrane. Although reports of corneal refractive surgery including laser-assisted in situ keratomileusis (LASIK), photorefractive keratectomy (PRK), and small incision lenticule extraction (SMILE) in PPCD are minimal, these procedures have been shown to be safe and effective in this patient population. Proceeding with corneal refractive surgery in eyes with PPCD raises concerns regarding corneal integrity, including long-term biomechanical instability, risk of ectasia, endothelial cell loss, disease progression, and corneal decompensation. Thus, LASIK, PRK, and SMILE should be considered with caution. This commentary explores the patient characteristics associated with favorable surgical outcomes and factors that weigh against proceeding with refractive surgery.

To Amputate or Not to Amputate: Management of Iatrogenic LASIK Flap Dehiscence and Epithelial Ingrowth with Overlying Pseudopterygium.

A 73-year-old male with a history of myopic laser-assisted in situ keratomileusis (LASIK) 20 years earlier presented with a late LASIK flap dehiscence, epithelial ingrowth, conjunctivalization, and the development of a pseudopterygium in the right eye. The findings were consistent with surgical trauma, likely occurring after corneal epithelial debridement to improve visualization during pars plana vitrectomy for retinal detachment repair 3 months earlier. The patient underwent epithelial ingrowth debridement, LASIK flap reapproximation and suturing, and a conjunctival limbal autograft from the contralateral eye. The surgery was completed successfully without the need for flap amputation. Postoperatively, the patient had an uneventful course with a well-healing conjunctival graft and no interface opacity or evidence of recurrent pseudopterygium of the right eye. The graft and corneal topography remained stable after subsequent cataract surgery.

Utilization of Intravenous Lidocaine Infusion for the Treatment of Refractory Chronic Pain.

CONTEXT: Chronic pain accounts for one of the most common reasons patients seek medical care. The financial burden of chronic pain on health care is seen by direct financial cost and resource utilization. Many risk factors may contribute to chronic pain, but there is no definite risk. Managing chronic pain is a balance between maximally alleviating symptoms by utilizing a therapeutic regimen that is safe for long-term use. Currently, non-opioid analgesics, NSAIDs, and opioids are some of the medical treatment options, but these have numerous adverse effects and may not be the best option for long-term use. However, Lidocaine can achieve both central and peripheral analgesic effects with relatively few side effects, which may be an ideal compound for managing chronic pain. EVIDENCE ACQUISITION: This is a Narrative Review. RESULTS: Infusion of lidocaine (2-(diethylamino)-N-(2,6-dimethylphenyl)acetamide), an amino-amide compound, is emerging as a promising option to fill the therapeutic void for treatment of chronic pain. Numerous studies have outlined dosing protocols for lidocaine infusion for the management of perioperative pain, outlined below. While there are slight variations in these different protocols, they all center around a similar dosing regimen to administer a bolus to reach a rapid steady state, followed by infusion for up to 72 hours to maintain the therapeutic analgesic effects. CONCLUSIONS: Lidocaine may be a promising pharmacologic solution with a low side effect profile that provides central and peripheral analgesia. Even though the multifaceted mechanism is not entirely understood yet, lidocaine may be a promising novel remedy in treating chronic pain in various conditions.

Quantification of hair cortisol concentration in common marmosets (Callithrix jacchus) and tufted capuchins (Cebus apella).

Quantifying cortisol concentration in hair is a non-invasive biomarker of long-term hypothalamic-pituitary-adrenal (HPA) activation, and thus can provide important information on laboratory animal health. Marmosets (Callithrix jacchus) and capuchins (Cebus apella) are New World primates increasingly used in biomedical and neuroscience research, yet published hair cortisol concentrations for these species are limited. Review of the existing published hair cortisol values from marmosets reveals highly discrepant values and the use of variable techniques for hair collection, processing, and cortisol extraction. In this investigation we utilized a well-established, standardized protocol to extract and quantify cortisol from marmoset (n = 12) and capuchin (n = 4) hair. Shaved hair samples were collected from the upper thigh during scheduled exams and analyzed via methanol extraction and enzyme immunoassay. In marmosets, hair cortisol concentration ranged from 2,710 to 6,267 pg/mg and averaged 4,070 ± 304 pg/mg. In capuchins, hair cortisol concentration ranged from 621 to 2,089 pg/mg and averaged 1,092 ± 338 pg/mg. Hair cortisol concentration was significantly different between marmosets and capuchins, with marmosets having higher concentrations than capuchins. The incorporation of hair cortisol analysis into research protocols provides a non-invasive measure of HPA axis activity over time, which offers insight into animal health. Utilization of standard protocols across laboratories is essential to obtaining valid measurements and allowing for valuable future cross-species comparisons.