Ultrastructural Integrity of Human Capsulotomies Created by a Thermal Device.

PURPOSE: To investigate the ultrastructural features of anterior capsulotomy performed with a thermal device, the precision pulse capsulotomy (PPC). DESIGN: Prospective, multicenter case series. PARTICIPANTS: Consecutive patients undergoing capsulotomy with the PPC device. METHODS: Prospective study of patients undergoing capsulotomy with the PPC by 2 surgeons, followed up by routine phacoemulsification cataract surgery, was undertaken. All capsulotomy specimens were collected for scanning electron microscopy (SEM). Observations were made regarding uniformity of the capsular edge and the presence of irregularities that may compromise integrity. Comparisons were made with manual continuous curvilinear capsulorrhexis. MAIN OUTCOME MEASURES: Ultrastructural features of PPC and presence of irregularities. RESULTS: Frayed appearance of the anterior capsule edge was noted in postoperative visits under slit-lamp examination. Scanning electron microscopy sampling showed a generally uniform rolled capsular edge, but interspersed with areas of irregularity with frayed appearance at the capsule margin. CONCLUSIONS: The PPC device is capable of creating reproducible, central, and precise circular capsulotomy. The ultrastructural features in ex vivo human capsulotomy specimens generally show eversion of the capsulotomy edge, but in some cases, this was accompanied by areas of irregular capsule margin with frayed edges, likely caused by dissipated thermal energy. The postoperative appearance and SEM features warrant further assessment of the PPC integrity and clinical correlation.

Aqueous Chlorhexidine for Intravitreal Injection Antisepsis: A Case Series and Review of the Literature.

PURPOSE: To determine the incidence of endophthalmitis in a large clinical series using aqueous chlorhexidine for antisepsis before intravitreal injection and to review the ophthalmic literature regarding chlorhexidine efficacy and safety. DESIGN: Multicenter retrospective case series. PARTICIPANTS: All patients receiving intravitreal injections from 7 retinal specialists. METHODS: An audit of intravitreal injections performed by retinal specialists who exclusively used aqueous chlorhexidine 0.05% or 0.1% for prophylaxis of infective endophthalmitis was undertaken. The incidence of endophthalmitis was determined from August 1, 2011, to February 28, 2015. A literature review was performed to critically appraise the ocular safety and efficacy of aqueous chlorhexidine. MAIN OUTCOME MEASURES: Incidence of endophthalmitis after intravitreal injections. RESULTS: A total of 40 535 intravitreal injections were performed by 7 retinal specialists across 3 centers. Chlorhexidine was well tolerated, and only 1 patient with a suspected allergic reaction was noted. Three cases of endophthalmitis were identified with 1 culture-positive case. The 0.0074% (1 in 13 512) per-injection rate of endophthalmitis in this series compares favorably with previous series in which povidone-iodine has been used. CONCLUSIONS: Aqueous chlorhexidine was associated with a low rate of postinjection endophthalmitis and was well tolerated by patients.

A Comparative Cohort Study of Visual Outcomes in Femtosecond Laser-Assisted versus Phacoemulsification Cataract Surgery.

PURPOSE: To evaluate visual outcomes after femtosecond laser-assisted cataract surgery (LCS) with phacoemulsification cataract surgery (PCS). DESIGN: Prospective, multicenter, comparative case series. PARTICIPANTS: Consecutive patients undergoing femtosecond LCS or PCS with intraocular lens insertion. METHODS: A total of 1876 eyes of 1238 patients (422 male and 772 female) who underwent cataract surgery between January 2012 and June 2014 were included in the study: 1017 eyes from center A and 859 eyes from center B. Cases underwent clinico-socioeconomic selection. Patients with absolute LCS contraindications were assigned to PCS; otherwise, all patients were offered LCS and elected on the basis of their decision to pay (the out-of-pocket cost for LCS). Demographic and postoperative data were collected to determine differences between groups. MAIN OUTCOME MEASURES: Six-month postoperative visual and refractive outcomes. Masked subjective refractions were performed 2 to 6 months postoperatively. RESULTS: There were 988 eyes in the LCS group and 888 eyes in the PCS group. Baseline best-corrected visual acuity (BCVA) was better in LCS compared with PCS (20/44.0 vs. 20/51.5; P < 0.0003). Preoperative surgical refractive aim differed significantly between groups (LCS -0.28 vs. PCS -0.23; P < 0.0001). More patients who received LCS had Toric lenses implanted compared with PCS (47.4% vs. 34.8%; P < 0.0001). Postoperative BCVA was better after LCS (20/24.5 vs. 20/26.4; P = 0.0003) with a greater proportion of LCS cases achieving BCVA >20/30 (LCS 89.7% vs. PCS 84.2%; P = 0.0006) and 20/40 (LCS 96.6% vs. PCS 93.9%; P = 0.0077). However, PCS cases had more letters gained compared with LCS cases (13.5 vs. 12.5 letters; P = 0.0088), reflecting baseline BCVA differences. Mean absolute error was higher in LCS compared with PCS (0.41 diopters [D] vs. 0.35 D; P < 0.0011). The percentage of eyes within 0.5 D of error from preoperative aim refraction was higher in the PCS group (LCS 72.2% vs. PCS 82.6%; P < 0.0001). CONCLUSIONS: Femtosecond LCS did not demonstrate clinically meaningful improvements in visual outcomes over conventional PCS.

Inferring landscape-scale land-use impacts on rivers using data from mesocosm experiments and artificial neural networks.

Identifying land-use drivers of changes in river condition is complicated by spatial scale, geomorphological context, land management, and correlations among responding variables such as nutrients and sediments. Furthermore, variations in standard metrics, such as substratum composition, do not necessarily relate causally to ecological impacts. Consequently, the absence of a significant relationship between a hypothesised driver and a dependent variable does not necessarily indicate the absence of a causal relationship. We conducted a gradient survey to identify impacts of catchment-scale grazing by domestic livestock on river macroinvertebrate communities. A standard correlative approach showed that community structure was strongly related to the upstream catchment area under grazing. We then used data from a stream mesocosm experiment that independently quantified the impacts of nutrients and fine sediments on macroinvertebrate communities to train artificial neural networks (ANNs) to assess the relative influence of nutrients and fine sediments on the survey sites from their community composition. The ANNs developed to predict nutrient impacts did not find a relationship between nutrients and catchment area under grazing, suggesting that nutrients were not an important factor mediating grazing impacts on community composition, or that these ANNs had no generality or insufficient power at the landscape-scale. In contrast, ANNs trained to predict the impacts of fine sediments indicated a significant relationship between fine sediments and catchment area under grazing. Macroinvertebrate communities at sites with a high proportion of land under grazing were thus more similar to those resulting from high fine sediments in a mesocosm experiment than to those resulting from high nutrients. Our study confirms that 1) fine sediment is an important mediator of land-use impacts on river macroinvertebrate communities, 2) ANNs can successfully identify subtle effects and separate the effects of correlated variables, and 3) data from small-scale experiments can generate relationships that help explain landscape-scale patterns.

Anterior capsulotomy integrity after femtosecond laser-assisted cataract surgery.

OBJECTIVE: To compare the incidence of anterior capsular tears after femtosecond laser-assisted cataract surgery (FLACS) versus phacoemulsification cataract surgery (PCS) and to assess the ultrastructural features of anterior capsulotomy specimens (FLACS and PCS) using electron microscopy. DESIGN: Prospective, multicenter, comparative cohort case series. PARTICIPANTS: Consecutive patients undergoing FLACS or PCS. METHODS: A prospective cohort study of all patients (n = 1626) undergoing FLACS or PCS by 2 surgeons from centers A and B was undertaken to compare the incidence of anterior capsule tears. Anterior lens capsules were collected by 4 surgeons from centers A, B, C, and D using 3 different commercially available femtosecond platforms, each with latest version upgrades. Lens capsule tissue was prepared for scanning electron microscopy (SEM) using a total of 10 samples for patients undergoing PCS, and 40 samples for patients undergoing FLACS. MAIN OUTCOME MEASURES: Incidence of anterior capsule tear and comparative ultrastructural features of capsular samples from both PCS and FLACS cases. RESULTS: There was a significantly increased rate of anterior capsule tears in the FLACS group (15/804 [1.87%]) when compared with the PCS group (1/822 [0.12%]; P = 0.0002, Fisher exact test). In 7 cases, the anterior capsule tear extended to the posterior capsule. Because all cases had occurred in complete capsulotomy, the integrity of the anterior capsule was questioned in the FLACS group. Subsequent SEM sampling showed irregularity at the capsule margin, as well as multiple apparently misplaced laser pits in normal parts of the tissue. Aberrant pits were approximately 2 to 4 µm apart and occurred at a range of 10 to 100 µm radially from the capsule edge. CONCLUSIONS: Laser anterior capsulotomy integrity seems to be compromised by postage-stamp perforations and additional aberrant pulses, possibly because of fixational eye movements. This can lead to an increased rate of anterior capsule tears, and extra care should be taken during surgery after femtosecond laser pretreatment has been performed. A learning curve may account for some of the increased complication rate with FLACS. However, the SEM features raise safety concerns for capsular integrity after FLACS and warrant further investigation.

Craniopharyngioma: a review of long-term visual outcome.

PURPOSE: To assess the clinical presentation and long-term visual outcome in a series of patients with craniopharyn-gioma. METHODS: Retrospective case review. RESULTS: Thirty-six patients were reviewed, comprising 19 female patients and 17 male patients. The age range was 2-77 years with a bimodal distribution of 17 children (mean age 10 years) and 19 adults (mean age 47 years). Blurred vision was the most common visual complaint (23 cases, 64%) and headache the most frequent systemic complaint (19 cases, 53%). The average duration of systemic symptoms was 45 weeks compared to 10 weeks for visual symptoms. Deficits in visual acuity occurred in 13 patients (36%) and showed no significant change from initial presentation to final review. Sixteen patients (44%) had bitemporal hemianopia on presentation and pleomorphism (change from one type of visual field defect to another) occurred in 11 patients. Recurrence of tumour occurred in 15 patients (42%) and was more likely in children (59%) than adults (26%). The mean time period to recurrence was 7 years. The average follow-up period for all cases was 10 years. CONCLUSION: Patients with craniopharyngioma generally present late, and the visual symptoms are often preceded by a long history of systemic symptoms. Children are more likely to present with systemic symptoms than adults. Visual field pleomorphism is a feature of craniopharyngioma and occurred in one-third of the patients. Local recurrence is common. Although magnetic resonance imaging is the recommended means of follow up, regular neuro-ophthalmic review is useful in the early detection of anterior visual pathway compression by recurrent tumour.

Orbital lipomatous haemangiopericytoma: an unusual variant.

Haemangiopericytoma (HPC) of the orbit is a rare tumour occurring in all age groups and presenting with slowly progressive proptosis, ocular motility impairment and visual loss. Although most are benign tumours that are resectable at diagnosis, one-third of these tumours demonstrate malignant features and recur locally or metastasize, usually with a fatal outcome. In 1995, a morphologically unique variant, termed lipomatous haemangiopericytoma (L-HPC), was described. Only one case has been reported previously arising in the orbit. In this paper, a case is reported of L-HPC occurring in the orbit and consider the prognostic implications of this HPC variant.