Jennifer Hasenyager Smith

Effects of Photocoagulation on Intraretinal Po2 in Cat

PURPOSE To test the hypothesis that intraretinal Po(2) increases after photocoagulation. METHODS Anesthetized cats underwent retinal argon laser photocoagulation. At least 4 weeks after treatment, Po(2)-sensitive microelectrodes were used to record intraretinal Po(2) profiles from healed photocoagulation lesions in anesthetized cats breathing air. Histopathologic examination of the retinas was used to confirm that the photoreceptors were destroyed and that the inner retinal layers were preserved, though somewhat disorganized, as in human panretinal photocoagulation (PRP). RESULTS The retina and tapetum were thinner in the lesioned retina than in the nonphotocoagulated retina. Average Po(2) across the inner 50% of the retina was higher (22 +/- 10 mm Hg) in photocoagulated retina than in untreated retina (14 +/- 7 mm Hg; P < 0.01; n = 13 cats). The minimum Po(2) was also significantly higher, whereas choroidal Po(2) was significantly lower in the photocoagulated retina than in untreated retina. No significant difference was found in the preretinal vitreous. After lesions, inner retinal Po(2) could also be maintained above zero, even in the absence of retinal circulation. CONCLUSIONS Previous measurements showed increased Po(2) in the preretinal vitreous of rabbits and pigs (but not cats) after photocoagulation of the outer retina. These intraretinal measurements in cats provide further evidence for a chronic increase in inner retinal Po(2) in lesioned areas during air breathing.

Spontaneous regression of orbital Langerhans cell granulomatosis in a three-year-old girl.

PURPOSE To report a case of spontaneous regression of orbital Langerhans cell granulomatosis. METHOD Case report. A 3-year-old girl was initially examined with a 5-week history of slowly progressive blepharoptosis and periorbital swelling of the left eye. RESULTS Computed tomographic scan showed a mass in the left orbit eroding into the left frontal bone; fine-needle aspiration confirmed diagnosis of Langerhans cell granulomatosis. After initial biopsy, the patient was treated by close observation alone. Six months after initial examination, the monostotic lesion had completely resolved. CONCLUSIONS In some cases of monostotic Langerhans cell granulomatosis, initial biopsy followed by observation alone may allow for the spontaneous regression of the lesion. This conservative approach to treatment is an important therapeutic option that may spare the patient the adverse effects of surgical resection, radiation, or chemotherapy.

Teaching phacoemulsification in US ophthalmology residencies: can the quality be maintained?

Purpose of review To examine the current status of phacoemulsification training and the factors that will influence the future quality of training in phacoemulsification. Recent findings Recent developments include residents performing phaco without previous ECCE experience, residents using topical anesthesia in early surgical cases, virtual surgery, improved techniques for surgical practice with animal eyes, and modular surgical training. Summary Learning to perform cataract surgery is a universal experience for US ophthalmologists. Training in phacoemulsification during residency is one of the most important components of postgraduate education in ophthalmology. The quality of phacoemulsification training in the US is currently threatened by a confluence of factors including decreasing surgical numbers, rapidly changing technology, and shrinking financial resources. The impending decline in quality of phacoemulsification training in US residencies can be prevented if creative and innovative solutions to these problems are applied. These types of solutions include use of improved animal eye practice, virtual surgical practice, alterations in live surgery teaching techniques, and finding additional sources of financial support for surgical teaching.

Decreased Circulation in the Feline Choriocapillaris Underlying Retinal Photocoagulation Lesions

PURPOSE To investigate the effects of argon laser photocoagulation on the choroidal circulation in cats. METHODS Three sizes of argon laser lesions designed to damage the outer retina were created in six cats: larger than 1 mm, 500 μm, and 200 μm. At least 1 month after the lesions, damage to the choroidal vasculature was studied in two ways. First, scanning laser ophthalmoscopy was used to obtain infrared reflectance (IR) photographs and indocyanine green (ICG) angiograms. Second, fluorescent microspheres (15 μm) were injected into the left ventricle. The globes were fixed, the choroid was flat mounted, and images were taken with a fluorescence microscope. Retinal histology was assessed in comparable lesions. RESULTS Histology showed that the inner retina was preserved, but the choroid, tapetum, and outer retina were damaged. ICG angiograms revealed choriocapillaris loss in large lesions and in some 500-μm lesions, whereas the larger vessels were preserved; in 200 μm lesions, choriocapillaris loss was not detectable. However, in all lesions, the distribution of microspheres revealed little if any choriocapillaris flow. In larger lesions, the damaged region was surrounded by an area in which the number of microspheres was higher than in the lesion but lower than in the normal retina. CONCLUSIONS Under lesions that destroyed photoreceptors, the choriocapillaris was also compromised, even when no change could be detected with ICG angiography. Panretinal photocoagulation is designed to increase retinal PO2 by allowing choroidal oxygen to reach the inner retina, but its effectiveness may be limited by damage to the choriocapillaris.

Siblings of retinoblastoma patients: are we underestimating their risk?

PURPOSE To describe the clinical presentation of probable germ-line mosaicism in four retinoblastoma kindreds. METHODS Review of 255 retinoblastoma patients and their family records in a University of California, San Francisco-Bascom Palmer database to identify those with potential germ-line mosaicism. Parents and siblings of retinoblastoma patients were given comprehensive ophthalmologic examinations. RESULTS Four kindreds were identified, wherein retinoblastoma was diagnosed in two siblings and both parents demonstrated no evidence of retinoblastoma or retinocytoma. CONCLUSION Clinical appearance of germ-line mosaicism is demonstrated in our retinoblastoma patient populations. We recommend routine clinical screening of all parents and siblings of retinoblastoma patients to provide more accurate genetic counseling and to allow earlier examination and treatment of children at presymptomatic disease stages. Germ-line mosaicism must be considered as a genetic transmission pattern in these patients, and genetic counseling should specifically recognize this possibility. If a parent is germ-line mosaic, the possibility of bearing a second child with retinoblastoma is clearly higher than conventionally believed.

Ocular manifestations of systemic malignancies.

Ocular manifestations of systemic malignancy are important for both the ophthalmologist and the internist to recognize because they may precede the diagnosis of cancer. This review of the current literature discusses the clinical manifestations, etiology, and potential therapeutic interventions for a group of visual paraneoplastic syndromes, including carcinoma-associated retinopathy and melanoma-associated retinopathy. These conditions are characterized by elevated serum levels of autoantibodies directed against tumor antigen that cross-react with retinal proteins, resulting in rod and cone dysfunction. The clinical presentation, site of origin, frequency, and intraocular distribution of tumors metastatic to the eye are also reviewed.

The disappearing “melanoma”

Editor,—Uveal melanoma is the most common primary intraocular malignancy in adults. Accurate diagnosis relies upon evaluation by indirect ophthalmoscopy as well as on characteristic features present on ancillary tests such as ultrasonography and angiography. Masquerading lesions can occasionally provide diagnostic challenges. Common simulating lesions include choroidal naevi, metastases, haemangioma, osteoma, CHRPE, and disciform scar.1 We report the case of a patient with a lesion simulating an intraocular melanoma which resulted from the development of an orbital cyst that indented the globe. ### CASE REPORT A 49 year old white male was referred with a diagnosis of an intraocular melanoma. He complained of progressively decreasing vision in his right eye over the previous 1.5 years. His medical history was …

Investigating the Support Networks for Mothers of a High-density Public Housing Community and the Effects of Housing Closures on These Support Systems

Over the past few decades, public housing initiatives have focused on the decentralization of poverty by replacing high-density public housing (HDPH) models with lower-density, mixed-income models. This action has resulted in the displacement of families who had lived in these developments for generations. In past studies, public housing residents have been shown to have stronger social ties than those living in other types of assisted housing. Research on the dismemberment of US public housing has demonstrated a “root shock” or disruption in the support infrastructure in these resource-limited communities. The purpose of this study was to use intergenerational analysis to analyze support systems of mothers in a low-income community and to investigate how the dismemberment of a Chicago HDPH community, Cabrini Green, affected parenting experiences and support infrastructure. Two generations of the former HDPH community were interviewed: (Gen1) mothers who raised their children in Cabrini Green and (Gen2) their daughter(s) who were raised in Cabrini Green but who now raise their children elsewhere. Interviews were analyzed for common themes in relation to mental health, social support networks, and parenting experiences. Four main components of parenting support were identified: familial support, father of child support, community support, and institutional support. Interviews suggest that the closing of Cabrini-Green high-rise buildings impacted relative contributions from specific components of mothers’ support infrastructure, particularly community and institutional support. Mothers with support void in one component of support had better outcomes if they had the reserve to compensate by increasing one or more other areas of support. Programs that foster other sources of parenting support during and after public housing closures may help to improve outcomes for mothers and their families. By analyzing the experiences of mothers of both generations, we also gain insight into how experiences of motherhood and support systems compared before and after Cabrini Green’s dissolution as well as insight into the participants’ views on the impact of the housing closing on the parenting experience.

Study protocol for a cluster randomised controlled factorial design trial to assess the effectiveness and feasibility of reactive focal mass drug administration and vector control to reduce malaria transmission in the low endemic setting of Namibia

Introduction To interrupt malaria transmission, strategies must target the parasite reservoir in both humans and mosquitos. Testing of community members linked to an index case, termed reactive case detection (RACD), is commonly implemented in low transmission areas, though its impact may be limited by the sensitivity of current diagnostics. Indoor residual spraying (IRS) before malaria season is a cornerstone of vector control efforts. Despite their implementation in Namibia, a country approaching elimination, these methods have been met with recent plateaus in transmission reduction. This study evaluates the effectiveness and feasibility of two new targeted strategies, reactive focal mass drug administration (rfMDA) and reactive focal vector control (RAVC) in Namibia. Methods and analysis This is an open-label cluster randomised controlled trial with 2×2 factorial design. The interventions include: rfMDA (presumptive treatment with artemether-lumefantrine (AL)) versus RACD (rapid diagnostic testing and treatment using AL) and RAVC (IRS with Acellic 300CS) versus no RAVC. Factorial design also enables comparison of the combined rfMDA+RAVC intervention to RACD. Participants living in 56 enumeration areas will be randomised to one of four arms: rfMDA, rfMDA+RAVC, RACD or RACD+RAVC. These interventions, triggered by index cases detected at health facilities, will be targeted to individuals residing within 500 m of an index. The primary outcome is cumulative incidence of locally acquired malaria detected at health facilities over 1 year. Secondary outcomes include seroprevalence, infection prevalence, intervention coverage, safety, acceptability, adherence, cost and cost-effectiveness. Ethics and dissemination Findings will be reported on clinicaltrials.gov, in peer-reviewed publications and through stakeholder meetings with MoHSS and community leaders in Namibia. Trial registration number NCT02610400; Pre-results.

Surgical Technique — How to Perform a Smooth Transition

The advantages of micro incision phaco outweigh any increased difficulty or complications that occur during a surgeons early experience with the technique. The many advantages of biaxial micro incision phaco are easily accessible to the skilled cataract surgeon.