Contralateral Forced Eyelid Closure Increases Intraocular Pressure.

OBJECTIVES: The purpose of the study was to describe the influence of contralateral forced eyelid closure on intraocular pressure (IOP). METHODS: Twenty-one healthy volunteers with no ophthalmic history had their IOP measured in the supine position to simulate the intraoperative environment. Intraocular pressure was measured with a handheld tonometer over three scenarios: (1) both eyes in a relaxed state, (2) eyelid speculum in the right eye with both eyes open and relaxed, (3) eyelid speculum in the right eye with the fellow eye squeezing tightly. RESULTS: Intraocular pressure significantly increased with forced contralateral eyelid squeezing compared with the relaxed state by a mean of 7.71±5.08 mm Hg (95% Confidence Interval of 5.40-7.37), P<0.001. CONCLUSIONS: Contralateral eyelid squeezing can significantly increase intraoperative IOP measurements.

Insect Fungus Metarhizium robertsii Is a Rare Causative Agent of Keratitis.

PURPOSE: This study aimed to describe a case of keratitis secondary to Metarhizium robertsii, a soil-dwelling fungus with typical insect pathogenicity. METHODS: A Case report. RESULTS: A 58-year-old man with a ocular history of soft contact lens overwear, poor contact lens hygiene, and ocular exposure to ground well water supplying his house was referred to our university practice for a central corneal ulcer with 40% thinning. Same-day rapid microscopic detection with Giemsa stain identified the presence of many hyphae elements, and he was ultimately diagnosed with M. robertsii keratitis. The patient's course involved severe and progressive corneal thinning that stabilized over a 3-month course of antifungal therapy. CONCLUSIONS: Metarhizium robertsii seems more aggressive than other forms of fungal keratitis; therefore, this infection may be watched more closely with the risk for quick progressive corneal thinning, even while on antifungal management.

Sterile iris abscess associated with herpes zoster ophthalmicus.

PURPOSE: To report a case of a sterile iris abscess associated with herpes zoster ophthalmicus (HZO). OBSERVATIONS: A 69-year-old African American female presented to SUNY Downstate Medical Center complaining of left-sided eye pain for two weeks. The patient had a best-corrected visual acuity of 20/30 OD and 20/200 OS. On external exam, vesicles were noted on the left upper lid and tip of the nose. Anterior segment exam was notable for decreased sensation without epithelial defects. The patient had 2+ stromal edema with 3+ cell and flare. The iris was flat with 1+ nuclear sclerosis OU. The intraocular pressure (IOP) was 14 mmHg OD and 40 mmHg OS. The patient was diagnosed with HZO with secondary uveitic glaucoma.At ten weeks, anterior segment inflammation resolved and IOP stabilized. However, an iris nodule was noted superior nasal which continued to enlarge by 16 weeks follow up. Iris ultrasound revealed a 3 × 3 mm elevated lesion with internal homogeneity suggestive of an abscess.At five months, a dense, mature cataract developed. The patient underwent cataract extraction with sector iridectomy. Gram staining and cultures were negative for organisms but positive for polymorphic neutrophils. Histopathology revealed fibrosis, surface necrosis, and stromal infiltration with chronic inflammatory cells consistent with chronic iritis and a sterile abscess secondary to HZO. CONCLUSIONS AND IMPORTANCE: HZO is associated with a range of ocular sequelae with acquired iris nodule only mentioned once in the literature. As the second documented case, our findings will add to the general fund of knowledge regarding iris lesions and HZO.

Update on corneal collagen crosslinking for ectasia.

PURPOSE OF REVIEW: Corneal collagen crosslinking (CXL) is a minimally invasive treatment that can stabilize corneal ectatic disorders including keratoconus, pellucid marginal degeneration, or postrefractive surgery ectasia. The benefits of CXL have been well documented. New research is focused on modifying current treatment protocols with the goals of maximizing corneal stability while also shortening overall procedure time. RECENT FINDINGS: Accelerated CXL protocols have the goal of delivering the same ultraviolet A intensity as conventional protocols, but over a shorter time period. Accelerated protocols have shown success to date, but there are concerns for long-term corneal stability. Pulsed protocols may increase the long-term efficacy of the accelerated designs. In addition, transepithelial crosslinking protocols have been designed with the goal of reducing postoperative pain and lower the risk of infectious complications of epithelial-off conventional protocols. SUMMARY: Newer CXL protocols attempt to make the procedure safer and more effective. Current research is promising, but long-term studies are essential to understand how the new protocols may affect corneal stability.

Comparison of Clinical Features and Treatment Outcomes of Pseudomonas aeruginosa Keratitis in Contact Lens and Non-Contact Lens Wearers.

PURPOSE: To compare the outcomes of Pseudomonas aeruginosa keratitis (PAK) in contact lens wearers (CLWs) and non-contact lens wearers (non-CLWs) and identify risk factors for poor visual acuity (VA) outcomes in each group. DESIGN: Retrospective cohort study METHODS: Two hundred fourteen consecutive cases of PAK were included between January 2006 and December 2019. Clinical features, microbiologic results, and treatment course were compared between CLW and non-CLW groups. Analyses of clinical features predicting poor final VA were performed. RESULTS: This study identified 214 infected eyes in 207 patients with PAK, including 163 eyes (76.2%) in CLWs and 51 eyes (23.8%) in non-CLWs. The average age was 39.2 years in CLWs and 71.9 years in non-CLWs (P < .0001). The average logMAR visual acuity (VA) at presentation was 1.39 in CLWs and 2.17 in non-CLWs (P < .0001); average final VA was 0.76 in CLWs and 1.82 in non-CLWs (P < .0001). Stromal necrosis required a procedural or surgical intervention in 13.5% of CLWs and 49.0% of non-CLWs (P < .0001). A machine learning-based analysis yielded a list of clinical features that most strongly predict a poor VA outcome (worse than 20/40), including worse initial VA, older age, larger size of infiltrate or epithelial defect at presentation, and greater maximal depth of stromal necrosis. CONCLUSIONS: Non-CLWs have significantly worse VA outcomes and required a higher rate of surgical intervention, compared with CLWs. Our study elucidates risk factors for poor visual outcomes in non-CLWs with PAK.

Neisseria sicca: A Rare Cause of Bacterial Conjunctivitis.

BACKGROUND Neisseria-associated conjunctivitis is a rare cause of bacterial conjunctivitis in adults, with Neisseria gonorrhoeae as the primarily identified infectious strain. Here, we present a rare case of bacterial conjunctivitis due to Neisseria sicca in a 34-year-old immunocompetent man with no prior medical or ocular history. CASE REPORT A 34-year-old man with no significant past medical or ocular history presented with a 3-day history of left periorbital edema, ocular pain, and copious purulent discharge. Bacterial conjunctivitis was suspected due to the rapidity of onset and purulence. Peripheral corneal thinning was identified. Preliminary culture results showed gram-negative diplococci, and the patient was treated for gonococcal infection. Final cultures identified Neisseria sicca, a rarely pathogenic strain of Neisseria species. CONCLUSIONS This is the second reported case of Neisseria sicca-associated conjunctivitis, and the first reported case to have corneal involvement. Neisseria sicca, while typically non-pathogenic, may manifest as conjunctivitis in immunocompetent hosts with a low-risk sexual history.

Cognitive emotion regulation fails the stress test.

Cognitive emotion regulation has been widely shown in the laboratory to be an effective way to alter the nature of emotional responses. Despite its success in experimental contexts, however, we often fail to use these strategies in everyday life where stress is pervasive. The successful execution of cognitive regulation relies on intact executive functioning and engagement of the prefrontal cortex, both of which are rapidly impaired by the deleterious effects of stress. Because it is specifically under stressful conditions that we may benefit most from such deliberate forms of emotion regulation, we tested the efficacy of cognitive regulation after stress exposure. Participants first underwent fear-conditioning, where they learned that one stimulus (CS+) predicted an aversive outcome but another predicted a neutral outcome (CS-). Cognitive regulation training directly followed where participants were taught to regulate fear responses to the aversive stimulus. The next day, participants underwent an acute stress induction or a control task before repeating the fear-conditioning task using these newly acquired regulation skills. Skin conductance served as an index of fear arousal, and salivary α-amylase and cortisol concentrations were assayed as neuroendocrine markers of stress response. Although groups showed no differences in fear arousal during initial fear learning, nonstressed participants demonstrated robust fear reduction following regulation training, whereas stressed participants showed no such reduction. Our results suggest that stress markedly impairs the cognitive regulation of emotion and highlights critical limitations of this technique to control affective responses under stress.

FGF signalling generates ventral telencephalic cells independently of SHH.

Sonic hedgehog (SHH) is required to generate ventral cell types throughout the central nervous system. Its role in directly specifying ventral cells, however, has recently been questioned because loss of the Shh gene has little effect on ventral development if the Gli3 gene is also mutant. Consequently, another ventral determinant must exist. Here, genetic evidence establishes that FGFs are required for ventral telencephalon development. First, simultaneous deletion of Fgfr1 and Fgfr3 specifically in the telencephalon results in the loss of differentiated ventromedial cells; and second, in the Fgfr1;Fgfr2 double mutant, ventral precursor cells are lost, mimicking the phenotype obtained previously with a loss of SHH signalling. Yet, in the Fgfr1;Fgfr2 mutant, Shh remains expressed, as does Gli1, the transcription of which depends on SHH activity, suggesting that FGF signalling acts independently of SHH to generate ventral precursors. Moreover, the Fgfr1;Fgfr2 phenotype, unlike the Shh phenotype, is not rescued by loss of Gli3, further indicating that FGFs act downstream of Shh and Gli3 to generate ventral telencephalic cell types.

Sympathetic overactivity in active ulcerative colitis: effects of clonidine.

Previous reports suggest that inflammatory bowel diseases may be accompanied by abnormalities in the neural autonomic profile. We tested the hypotheses that 1) an exaggerated sympathetic activity characterizes active ulcerative colitis (UC) and 2) a reduction of sympathetic activity by clonidine would be associated with clinical changes of UC. In 23 patients with UC and 20 controls, muscle sympathetic nerve activity (MSNA), ECG, blood pressure, and respiration were continuously recorded, and plasma catecholamine was evaluated both at rest and during a 75 degrees head-up tilt. Autonomic profile was assessed by MSNA, norepinephrine, epinephrine, spectral markers of low-frequency (LF) cardiac sympathetic (LF(RR); normalized units) and high-frequency (HF) parasympathetic (HF(RR); normalized units) modulation and sympathetic vasomotor control (LF systolic arterial pressure; LF(SAP)), obtained by spectrum analysis of the R-R interval and systolic pressure variability. Among UC patients, 16 agreed to be randomly assigned to 8-wk transdermal clonidine (15 mg/wk, 9 subjects), or placebo (7 patients). An autonomic profile, Disease Activity Index (DAI), and endoscopic pattern were compared before and after clonidine/placebo. At rest, MSNA, heart rate (HR), LF(RR), LF/HF, and LF(SAP) were higher and HF(RR) was lower in patients than in controls. Tilt decreased HF(RR) and increased MSNA and LF(RR) less in patients than in controls. Clonidine decreased HR, MSNA, epinephrine, LF(RR), and increased HF(RR), whereas placebo had no effects. Changes of the autonomic profile after clonidine were associated with reduction of DAI score. An overall increase of sympathetic activity characterized active UC. Normalization of the autonomic profile by clonidine was accompanied by an improvement of the disease.

Effects of unilateral and bilateral carotid baroreflex stimulation on cardiac and neural sympathetic discharge oscillatory patterns.

BACKGROUND: Left and right carotid baroreflex afferents participate in generating the spontaneous variability of heart rate (HR), arterial pressure (AP), and muscle sympathetic nerve activity (MSNA), but the relative contribution of each side is unclear. Pathophysiological conditions unilaterally affecting carotid baroreceptor function might result in abnormal changes of HR, AP, and MSNA variability, thus markedly affecting prognosis. We tested the hypothesis that unilateral carotid baroreceptor perturbation might differentially affect HR, AP, and MSNA variability compared with stimulation of the opposite side. METHODS AND RESULTS: In 12 healthy volunteers, 4 sinusoidal neck suction procedures (0.1 Hz, from 0 to -50 mm Hg) were applied at the right, left, and combined right and left sides of the neck, in concordance or with phase opposition. Respiration was controlled at 0.25 Hz. Power spectrum analysis assessed the changes in the 0.1-Hz oscillatory component of the R-R interval, systolic AP (SAP), and MSNA variability induced by rhythmic baroreceptor stimulation. Mean R-R interval, SAP, and MSNA were unchanged during all procedures. The increase of the 0.1-Hz component of R-R and SAP variability during right and combined right and left carotid baroreceptor stimulation was greater than the changes induced by left-sided stimulation. The increase in the 0.1-Hz oscillatory component of MSNA variability was similar during all neck suction procedures. CONCLUSIONS: Right carotid baroreflex loading was as efficient as bilateral stimulation and more effective than left carotid suction in modulating R-R and SAP variability. There was no asymmetry in neural sympathetic discharge responses after single-sided carotid baroreceptor stimulation.