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: PurposeTo evaluate the intraocular pressure (IOP), best corrected visual acuity (BCVA), and glaucoma medication requirements in patients having phacoemulsification after preexisting glaucoma filters.: SettingOphthalmic Consultants of Boston, Boston, Massachusetts, USA.: MethodsA retrospective analysis of 58 eyes that had temporal phacoemulsification via a clear corneal (32 eyes) or a scleral tunnel (26 eyes) approach after filtration surgery was performed with a minimum follow-up of 12 months. Two-tailed homoscedastic t tests were used for statistical analysis.: ResultsThe mean preoperative IOP in all eyes was 11.8 mm Hg ± 4.2 (SD), and the mean final postoperative IOP was 13.7 ± 4.6 mm Hg (P<.022). The mean preoperative logMAR equivalent BCVA was 0.8 ± 0.4, which improved to a mean of 0.4 ± 0.4 postoperatively (P<.0000002). There was no statistically significant change in glaucoma medication requirements postoperatively. The differences in IOP, BCVA, and postoperative glaucoma medication requirements were not statistically significant between the clear corneal group and the scleral tunnel group or between patients who received mitomycin at the time of filtration surgery and those who did not. There were no intraoperative complications; 1 patient required additional glaucoma surgery.: ConclusionClear corneal or scleral tunnel phacoemulsification in the setting of a preexisting glaucoma filter was associated with improved BCVA, a small but statistically significant increase in IOP, and stability in the number of glaucoma medicines required for IOP control over a minimum follow-up of 1 year. [Copyright &y& Elsevier]

Provides information on a study measuring the functional responses of coyotes and lynx during a cyclic fluctuation of hare populations in the southwest Yukon, to determine their effects on the cyclic dynamics. Methodology used to conduct the study; Information on the monitoring of radio-collared predators; Diets of coyotes and lynx; Findings of the study.

Analyzes the early survival of juvenile snowshoe hares. Effects of food addition to survival; Causes of mortality; Relationship among survival rates, litter size and body size at birth; Life history traits.

There is wisdom in the saying that ‘To a person with a hammer everything looks like a nail’. As a therapist my hammer is talking, naturally and inevitably, and most things look like they need talking. But, there are times when I put my talking tool aside and select another tool and my three tennis balls are one of the tools for which I reach. [ABSTRACT FROM AUTHOR]

Groundberries are an important component of the flora of the boreal forest and provide seasonally important food for many birds and mammals, as well as local people in northern Canada. Here, we ask whether there has been a change in the cover of groundberries in the Yukon boreal forest over the last two decades. We monitored five common species at undisturbed forest sites spaced 300 km apart. At our Kluane site, we monitored 710 fixed quadrats per year for 26 years (1997–2022), and at Mayo 500 quadrats per year for 18 years (2005–2022). The cover of four species, Arctostaphylos uva-ursi (L.) Spreng. (bearberry), Arctostaphylos rubra (Rehder & E.H. Wilson) Fernald (red bearberry), Empetrum nigrum L. (crowberry), and Geocaulon lividum (Richardson) Fernald (toadflax), declined annually by 0.2%–0.8% at both sites. In contrast, Vaccinium vitis-idaea L. (lingonberry) increased annually by 0.5% and 0.8%. We tested whether increases in summer temperature and rainfall were correlated with the observed changes but found no significant relationships. These boreal plants are changing in abundance, but we have limited data on the extent and speed of these changes. We recommend experiments to understand the cause(s) of these changes in groundberry productivity. Our study is a start in monitoring important berry species in this critical ecosystem of northern Canada. [ABSTRACT FROM AUTHOR]

Discusses blurred vision and reviews the examination techniques and diagnostic algorithms that are useful in the evaluation of blurred vision. History of the eye exam; Topics of visual acuity, field, pupils, movement of extraocular muscles, and anterior and posterior segments; Causes of blurred vision; Conclusion that blurred vision is a complex symptom that needs proper diagnosis to distinguish pathologic causes from nonpathologic causes.

We evaluated evidence of an effect of climate on the numerical response of a coyote (Canis latrans) population to their keystone prey, snowshoe hares (Lepus americanus), in a Canadian boreal forest. Six a priori hypotheses of the coyote numerical response were developed that postulated linear, nonlinear, additive, and interactive effects of prey and climate. Model selection procedures showed the North Atlantic Oscillation (NAO) had the strongest effect on the coyote numerical response via its interaction with snowshoe hare density, while other large-scale climate indices had very weak effects. For a given snowshoe hare density, a negative value of the NAO amplified the abundance of coyote and a positive NAO decreased coyote abundance. We hypothesize that the coyote numerical response is ultimately determined by the coyote functional response influenced by winter conditions determined by the NAO. [ABSTRACT FROM AUTHOR]

PURPOSE: To analyze the outcomes of surgery for dislocated intraocular lenses (lOLs) in patients with pseudoexfoliation (PXF). SETTING: Private practice, Boston, Massachusetts, USA. DESIGN: Retrospective case study. METHODS: Eyes with PXF and I0L dislocations that had I0L exchange or repositioning were re-viewed. An outcomes analysis compared the surgical techniques with regard to corrected distance visual acuity (CDVA), intraocular pressure (I0P), and glaucoma medication requirements. RESULTS: The lOLexchange was performed in 64 eyes (79%) and I0L repositioning in 17 eyes (21 %). The CDVA improved in all eyes, from a preoperative mean of 0.78 logMAR ± 0.50 (SD) to a mean of 0.35 ± 0.31 logMAR at the final follow-up (mean 2.5 ± 2.6 years) (P<.0001). The mean IOP was reduced by 4.2 mm Hg at the final follow-up (P<.0001). The mean glaucoma medication requirement remained stable at the final follow-up compared with the preoperative levels (P>.05). There were no significant differences in the mean CDVA, IOP, or glaucoma medication requirement between eyes that had IOL exchange and eyes that had I0L repositioning. There were no significant intraoperative complications. The most common postoperative complication was a transient decrease in IOP to 5 mm Hg or lower or an increase in IOP to 30 mm Hg or higher. CONCLUSIONS: Patients with PXF having surgical treatment of IOL dislocation have the potential for excellent visual outcomes with minimal intraoperative and postoperative complications. [ABSTRACT FROM AUTHOR]

Purpose: To determine whether pupil stretch during phacoemulsification affects postoperative best corrected visual acuity (BCVA), intraocular pressure (IOP), and inflammation compared with results in patients without pupil stretch. Methods: A retrospective analysis of 115 eyes that had pupil stretch during phacoemulsification (study group) and 125 eyes without pupil stretch (control group) was performed with a minimum of 12 months follow-up. Single-factor analysis of variance and 2-tailed homoscedastic t tests were used for statistical analysis. Results: The mean preoperative logMAR equivalent BCVA was 0.5 ± 0.3 (SD) in the study group and 0.6 ± 0.4 in the control group. The mean preoperative IOP was 16.2 ± 4.1 mm Hg in the study group and 16.0 ± 3.5 mm Hg (control group). There was no statistically significant difference at postoperative follow-up of 1 year in BCVA or IOP between the 2 groups (1 year BCVA 0.2 ± 0.2 [study group], 0.2 ± 0.2 [control group] [P<.1]; IOP 14.5 ± 3.5 mm Hg and 14.7 ± 3.3 mm Hg, respectively [P<.7]). There was no significant difference in the number of glaucoma medications required for glaucoma patients preoperatively and postoperatively between the 2 groups (P<.5). Complications were rare, and there was no significant difference in the complications (ie, iritis, hyphema, cystoid macular edema, epiretinal membrane formation) between the 2 groups at 1 year. Conclusion: Pupil stretch during phacoemulsification was not associated with a statistically significant difference in BCVA, IOP, inflammation, or other complications postoperatively compared with results in the control group without pupil stretch. [Copyright &y& Elsevier]

Purpose: To compare the results of 1-site versus 2-site combination glaucoma filtration and phacoemulsification surgery with respect to visual acuity, intraocular pressure (IOP), and glaucoma medication requirements via a case control study. Methods: Results of 2-site phacotrabeculectomy surgery in 64 eyes of 59 patients were retrospectively reviewed with a minimum follow-up of 1 year. The 2-site procedures were compared with a randomly chosen control group of 71 1-site phacotrabeculectomies performed by the same surgeon. Results: The presurgical visual acuity, IOP, and glaucoma medication requirements did not differ significantly between the 2 groups. Mean final postoperative results at 1 year for 2-site versus 1-site eyes, respectively, were visual acuity 0.32 ± 0.353 (SD) and 0.32 ± 0.37 (P = .99), IOP 15.0 ± 3.7 mm Hg and 15.1 ± 6.3 mm Hg (P = .97), and glaucoma medication requirements 0.43 ± 0.90 and 0.61 ± 1.1 (P = .52). Conclusion: There was no statistically significant difference in the final visual acuity, IOP, or glaucoma medication requirements between the 2-site and 1-site groups. [Copyright &y& Elsevier]

Purpose: To analyze the intraocular pressure (IOP), glaucoma medication requirements, and visual acuity after glaucoma filtration surgery in pseudophakic eyes. Setting: Private practice, Boston, Massachusetts, USA. Methods: The results of glaucoma filtration surgery in 47 eyes of 40 pseudophakic patients with a minimum follow-up of 1 year were retrospectively reviewed. Eyes with previously surgically manipulated conjunctiva in the area of filtration were compared to eyes without previous manipulation. Results: Preoperatively, the mean IOP was 25 mm Hg ± 7.3 (SD); mean number of glaucoma medications, 3.3 ± 1.0; and mean logMAR visual acuity, 0.41 ± 0.38. At the final follow-up visit (mean 36.5 ± 31.5 months), the respective means were 13.6 ± 6.6 mm Hg (P<.001), 0.9 ± 1.4 (P<.001), and 0.46 ± 0.43 (P=.53). The mean postoperative IOP, glaucoma medication requirements, and visual acuity at the final follow-up in eyes with virgin conjunctiva and eyes with previously manipulated conjunctiva were, respectively, as follows: IOP, 12.5 ± 3.2 mm Hg and 14.1 ± 7.6 mm Hg (P=.52); medications, 1.1 ± 1.3 and 0.9 ± 1.4 (P=.66); and logMAR acuity, 0.6 ± 0.52 and 0.4 ± 0.39 (P=.23). Conclusions: Glaucoma filtration surgery in pseudophakic eyes significantly improved IOP and reduced glaucoma medication requirements while maintaining stability of vision. There were no statistically significant differences in final IOP, glaucoma medication requirements, or visual acuity between eyes with virgin conjunctiva and eyes with previously surgically manipulated conjunctiva. [Copyright &y& Elsevier]

: PurposeTo characterize the differences in technique, complications, and outcomes in a large series of cataract extractions in patients with and without pseudoexfoliation (PEX) syndrome.: SettingOphthalmic Consultants of Boston, Boston, Massachusetts, USA.: MethodsA retrospective analysis was performed of 297 cases of cataract extraction in patients with PEX and 427 cases of cataract extraction in patients without PEX. This study examined and quantified the intraoperative and postoperative complications, performed a comparative outcomes analysis of intraocular pressure (IOP) change, and determined the prevalence of systemic vascular diseases in these patients.: ResultsThe overall rate of vitreous loss was 4% (7/297) in the PEX population and 0% (0/427) in the non-PEX group. There were no overall differences in the rate of postoperative complications. At 2 years, IOP had declined from a mean of 16.8 to 13.9 mm Hg in the PEX group and from 16.3 to 14.4 mm Hg in the non-PEX group. The decline was significantly greater in the PEX group. The prevalence of hypertension and diabetes was significantly greater in the non-PEX group (50% and 11%, respectively) than in the PEX group (38% and 5%, respectively).: ConclusionsThe increased frequency of intraoperative complications during cataract extraction in PEX patients stemmed from zonular weakness rather than capsule tears. Postoperative IOP declines were greater in the PEX group even 2 years after cataract extraction, suggesting the potential for long-term improvement in outflow facility in patients with coexisting cataract and glaucoma. [Copyright &y& Elsevier]

Purpose: To study the effect of peripheral iridectomy (PI) in phacotrabeculectomy.Setting: Academic private glaucoma practice with a primarily white patient population.Methods: This retrospective study comprised 126 eyes of 117 patients randomized for PI or no PI during phacotrabeculectomy who were followed for 12 months. Postoperative parameters in both groups included intraocular pressure (IOP), bleb development, visual acuity, and complications.Results: There were no statistically significant differences between the 2 groups in visual acuity or IOP. Bleb development required significantly more 5-fluorouracil therapy in the no-PI group than in the PI group; however, bleb failure and the need for laser suturelysis were not significantly different between groups. Complications were rare in both groups.Conclusion: Phacotrabeculectomy without PI may be an acceptable alternative to the surgical management of co-existing cataract and glaucoma. [Copyright &y& Elsevier]

Determining the factors driving cyclic dynamics in species has been a primary focus of ecology. For snowshoe hares (Lepus americanus), explanations of their 10-year population cycles most commonly feature direct predation during the peak and decline, in combination with their curtailment in reproduction. Hares are thought to stop producing third and fourth litters during the cyclic decline and do not recover reproductive output for several years. The demographic effects of these reproductive changes depend on the consistency of this pattern across cycles, and the relative contribution to population change of late-litter versus early litter juveniles. We used monitoring data on snowshoe hares in Yukon, Canada, to examine the contribution of late-litter juveniles to the demography of their cycles, by assigning litter group for individuals caught in autumn based on body size and capture date. We found that fourth-litter juveniles occur consistently during the increase phase of each cycle, but are rare and have low over-winter survival (0.05) suggesting that population increase is unlikely to be caused by their occurrence. The proportion of third-litter juveniles captured in the autumn remains relatively constant across cycle phases, while over-winter survival rates varies particularly for earlier-litter juveniles (0.14–0.39). Juvenile survival from all litters is higher during the population increase and peak, relative to the low and decline. Overall, these results suggest that the transition from low phase to population growth may stem in large part from changes in juvenile survival as opposed to increased reproductive output through the presence of a 4th litter. [ABSTRACT FROM AUTHOR]

Purpose To evaluate the results of phacoemulsification and intraocular lens ( IOL) implantation in eyes with pseudoexfoliation ( PEX) and zonular weakness. Methods Two hundred and ninety-five patients (295 eyes) were recruited. This study is a retrospective case review of 143 PEX eyes with preoperative (Group 1) and intraoperative (Group 2) signs of zonular weakness, 76 PEX eyes (Group 3) and 76 non- PEX eyes without zonular weakness (Group 4) undergoing phacoemulsification and IOL implantation performed by single surgeon from year 1988 to 2010. Outcome measures included frequency of postoperative pseudophakodonesis, anterior capsule contraction and IOL decentration/dislocation. Postoperative vision, intraocular pressure (IOP) and glaucoma medication requirements were also assessed. A subanalysis on identical postoperative outcomes of capsular tension ring ( CTR) implantation was performed. Comparisons were made for 52 PEX eyes with zonular weakness receiving nonsutured CTR implantation (Group A), 91 PEX eyes with zonular weakness not receiving CTR implantation (Group B) and 142 PEX eyes without zonular weakness (Group C). Results Mean follow-up was 4.08 ± 0.48 years and maximum was 8.3 years. Both Groups 1 and 2 showed higher incidence of complications than Groups 3 and 4 (p < 0.01). Vision, IOP and glaucoma medication requirements were similar postoperatively for all four groups. Groups A and B had a significantly higher proportion of postoperative complications than Group C (p < 0.01). There was no significant difference in risk of developing these complications between Groups A and B (p = 0.64). Conclusion Postoperative complication rates are higher in PEX eyes with preoperative and/or intraoperative signs of zonular weakness undergoing phacoemulsification. Nonsutured CTR implantation does not prevent IOL and capsular complications postoperatively. [ABSTRACT FROM AUTHOR]

Snowshoe hares ( Lepus americanus Erxleben, 1777) fluctuate in 9-10 year cycles throughout much of their North American range. These cycles show large variations in cyclic amplitude and we ask what factors could cause amplitude variation. We gathered data from 1976 to 2012 on hare numbers in the boreal forest of Alaska, Yukon, Northwest Territories, and northern British Columbia to describe the amplitude of hare fluctuations and to evaluate four possible causes. First, weather could cause variation in amplitude via hare reproduction or survival, but this mechanism does not fit our data. Second, bottom-up processes involving forest succession could explain amplitude variation through changes in winter forage availability, but succession is too slow a variable in our study areas. Third, plant defenses entrained by hare over-browsing in one cycle can produce variation in plant quality and quantity in subsequent cycles. A mathematical model suggests this is a possible explanation. Fourth, predator recovery following the cyclic low is inversely related to hare cyclic amplitude, and the existing data are consistent with this mechanism. A standardized regional monitoring program is needed to improve our understanding of cyclic amplitude variation in hares and the possible role of predators and winter foods in affecting amplitude. [ABSTRACT FROM AUTHOR]

The trophic dynamics of the Yukon boreal forest have been under investigation at the Kluane Lake Research Station since 1973. We monitored and conducted experiments on the major species in this ecosystem, except the large mammals (for logistic reasons). The central problem has been to determine the causes of the 9 - 10 year cycle of snowshoe hares, and to achieve this we carried out several large-scale experiments manipulating food supplies, predator pressure, and soil nutrient availability to test hypotheses that food, predation, or habitat quality regulate populations. The hare cycle is driven top-down by predators, and most hares die because they are killed by predators. Predators also cause stress in female hares, and the stress response seems to be responsible for the loss of reproductive potential in the decline and low phases of the hare cycle. Many of the specialist predators and some herbivores in this ecosystem fluctuate with the hare cycle. Arctic ground squirrels do, but red squirrels do not, being linked closely to white spruce seed masting years. Small rodents fluctuate in numbers in two patterns. Red-backed voles and four species of Microtus voles have a 3 - 4 year cycle that seems to be driven by food supplies and social behaviour. Deer mice, in contrast, have fluctuated dramatically in the 38 years we have monitored them, but not cyclically. White spruce seed production varies with temperature and rainfall, but was not affected by adding nutrients in fertilizer. Global warming and reduced hare browsing in the last 20 years have helped to increase the abundance of shrubs in these forests. It will be challenging to predict how this system will change as climatic warming proceeds, because even closely related species in the same trophic level respond differently to perturbations. We recommend continued monitoring of the major species in these boreal forests. [ABSTRACT FROM AUTHOR]

The trophic dynamics of the Yukon boreal forest have been under investigation at the Kluane Lake Research Station since 1973. We monitored and conducted experiments on the major species in this ecosystem, except the large mammals (for logistic reasons). The central problem has been to determine the causes of the 9 - 10 year cycle of snowshoe hares, and to achieve this we carried out several large-scale experiments manipulating food supplies, predator pressure, and soil nutrient availability to test hypotheses that food, predation, or habitat quality regulate populations. The hare cycle is driven top-down by predators, and most hares die because they are killed by predators. Predators also cause stress in female hares, and the stress response seems to be responsible for the loss of reproductive potential in the decline and low phases of the hare cycle. Many of the specialist predators and some herbivores in this ecosystem fluctuate with the hare cycle. Arctic ground squirrels do, but red squirrels do not, being linked closely to white spruce seed masting years. Small rodents fluctuate in numbers in two patterns. Red-backed voles and four species of Microtus voles have a 3 - 4 year cycle that seems to be driven by food supplies and social behaviour. Deer mice, in contrast, have fluctuated dramatically in the 38 years we have monitored them, but not cyclically. White spruce seed production varies with temperature and rainfall, but was not affected by adding nutrients in fertilizer. Global warming and reduced hare browsing in the last 20 years have helped to increase the abundance of shrubs in these forests. It will be challenging to predict how this system will change as climatic warming proceeds, because even closely related species in the same trophic level respond differently to perturbations. We recommend continued monitoring of the major species in these boreal forests. [ABSTRACT FROM AUTHOR]

Snowshoe hares ( Lepus americanus Erxleben, 1777) fluctuate in 9-10 year cycles throughout much of their North American range. Regional synchrony has been assumed to be the rule for these cycles, so that hare populations in virtually all of northwestern North America have been assumed to be in phase. We gathered qualitative and quantitative data on hare numbers and fur returns of Canada lynx ( Lynx canadensis Kerr, 1792) in the boreal forest regions of Alaska, Yukon, Northwest Territories, and northern British Columbia to describe synchrony in the time window of 1970-2012. Broad-scale synchrony in lynx fur returns was strong from 1970 to about 1995 but then seemed to break down in different parts of this region. Hare populations at 20 sites in Alaska, the Yukon, and Northwest Territories showed peak populations that lagged by 1-4 years during the 1990s and 2000s cycles. The simplest hypothesis to explain these patterns of asynchrony in hare cycles is the movement of predators from British Columbia north into the Yukon and then east into the Northwest Territories and west into Alaska. A traveling wave of these cycles is clearly seen in the lynx fur returns from western Canada and Alaska from 1970 to 2009. One consequence of a failure of synchrony is that hare predators like Canada lynx and Great-horned Owls ( Bubo virginianus (Gmelin, 1788)) can move from one adjacent area to the next within this region and survive long enough to prolong low densities in hare populations that have declined earlier. [ABSTRACT FROM AUTHOR]

Purpose: To assess the short- and long-term effect of uneventful phacoemulsification, posterior chamber intraocular lens (IOL) implantation, and trabeculectomy on intraocular pressure (IOP) and glaucoma medication requirements in eyes with pseudoexfoliation glaucoma (PXG) and compare the results with those in eyes that had uneventful phacoemulsification only (reported in a previous study of the same cohort of pseudoexfoliation eyes). Setting: Private practice, Boston, Massachusetts, USA. Design: Comparative case series. Methods: A retrospective analysis was performed of consecutive PXG eyes that had uneventful combined phacoemulsification and trabeculectomy by the same surgeon. The change in IOP, glaucoma medication requirements, and logMAR corrected distance visual acuity was compared between the combined surgery group and the phaco-alone group. Results: The combined-surgery group (n = 138) had statistically significant reduced mean IOP and glaucoma medication requirements through 10 years postoperatively (P<.018). The change in IOP and glaucoma medication requirements was greater in the combined-surgery group than in the phaco-alone group (n = 240); this was statistically significant up to 7 years postoperatively (P<.022). The reduction in mean postoperative IOP was greater in eyes with a higher mean preoperative IOP. In the combined-surgery group, 13.8% of eyes required subsequent laser trabeculoplasty, glaucoma surgery, or both. Conclusions: Uneventful phacoemulsification, IOL implantation, and trabeculectomy resulted in significant long-term reduction in IOP and glaucoma medication requirements in eyes with PXG. Combined procedures resulted in greater and more longstanding reductions in IOP and glaucoma medication requirements and fewer 1-day postoperative IOP spikes than phacoemulsification alone. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned. [Copyright &y& Elsevier]

Purpose: To assess the frequency and results of cataract surgery with concurrent vitrectomy due to zonule weakness in eyes with pseudoexfoliation (PXF). Setting: Private practice, Boston, Massachusetts, USA. Methods: This retrospective nonrandomized study assessed consecutive eyes with PXF having cataract surgery. High risk was defined as preoperative phacodonesis, iridodonesis, or lens subluxation (subgroup 1); preoperative anterior chamber depth or angle-depth asymmetry between eyes confirmed by slitlamp biomicroscopy or gonioscopy, respectively (subgroup 2); or complicated cataract extraction related to zonule weakness in the fellow eye (subgroup 3). Exclusion criteria were previous vitrectomy, scleral buckle, or trabeculectomy surgery and combined cataract–glaucoma surgery. A comparative analysis of outcome parameters was performed. Results: Of the 1059 eyes evaluated, 38 had vitrectomy. Concurrent vitrectomy was required in 19 (15.6%) of 122 high-risk eyes and 19 (2.0%) of 937 non-high-risk eyes (P<.00001). The need for concurrent vitrectomy was greatest in subgroup 3 (72.7%) and subgroup 1 (42.9%). There was no statistically significant difference between the vitrectomy group and the no-vitrectomy group in the mean improvement in logMAR corrected distance visual acuity (CDVA) (P = .38) or mean change in intraocular pressure (IOP) (mean decrease 2.6 mm Hg ± 1.5 [SD] and 1.6 ± 0.5 mm Hg, respectively) (P = .47). Conclusion: Despite the need for vitrectomy and the attendant increased demands in postoperative care, both the vitrectomy group and no-vitrectomy group had improved logMAR CDVA and IOP. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned. [Copyright &y& Elsevier]

Purpose: To assess the effect of phacoemulsification with posterior chamber intraocular lens (IOL) implantation performed by a single surgeon on intraocular pressure (IOP) and glaucoma medication requirements in pseudoexfoliation (PFX) eyes with or without glaucoma. Setting: Private practice, Boston, Massachusetts, USA. Methods: This retrospective analysis comprised 1122 eyes with PFX having uneventful phacoemulsification with IOL implantation. Of the eyes, 882 did not have glaucoma (PFX group) and 240 had glaucoma (PXG group). A comparative outcomes analysis was performed; the analysis focused on IOP and change in glaucoma medication requirements between the 2 groups. Results: The mean IOP was statistically significantly reduced through 7 years postoperatively compared with preoperatively in the PFX group. The PXG group had reduced mean IOP for 1 year and reduced glaucoma medication requirements at almost all postoperative time intervals. Higher mean preoperative IOP was associated with a greater reduction in mean IOP postoperatively in both groups. Intraocular pressure spikes (>30 mm Hg) 1 day postoperatively occurred in 4% in the PFX group and 17% in the PXG group. Postoperatively, 2.7% of PFX eyes progressed to a need for glaucoma medication and 3.7% of PXG eyes progressed to a need for laser and/or glaucoma surgery. Conclusions: A long-term reduction in mean IOP occurred in PFX eyes with and without glaucoma. The IOP reduction was proportional to the preoperative IOP; higher preoperative IOP was associated with a greater reduction in IOP. Glaucoma progression in both groups was low, suggesting a protective effect of phacoemulsification on IOP in these eyes. [Copyright &y& Elsevier]

Purpose: To compare intraoperative and postoperative complications, best corrected visual acuity, intraocular pressure (IOP), and glaucoma medication requirements between eyes with clinically apparent pseudoexfoliation (PEX) and fellow eyes without PEX in patients having bilateral cataract surgery. Setting: Private practice, Boston, Massachusetts, USA. Methods: This retrospective study comprised 1000 consecutive patients who had cataract surgery performed by the same surgeon. Of the 1000 patients, 137 had unilateral PEX and bilateral cataract surgery. Patients with previous or concurrent glaucoma surgery were eliminated from the study. Two-way analysis of variance and Tukey post hoc tests were used for statistical analysis. Results: Complications were few, with no significant differences between the 2 groups intraoperatively (zonule instability) or postoperatively (corneal edema, cystoid macular edema, intraocular lens decentration). Both groups had improved visual acuity, with no statistically significant between- group difference in acuity at 1 year. Both groups had decreased IOP postoperatively, although the eyes with PEX had a significantly greater mean Δ IOP than the fellow eyes without PEX (P<.016). The PEX group required more glaucoma medications overall (P<.003) and needed more glaucoma medications at 3 to 5 years than preoperatively; the medication requirement in the fellow-eye group remained stable. Conclusions: The presence of clinically apparent PEX had an impact on IOP reduction and glaucoma medication requirements. There were no differences in intraoperative or postoperative complications between eyes with PEX and fellow eyes without PEX. [Copyright &y& Elsevier]

Purpose: To determine the incidence of hypotony and intraocular pressure (IOP) elevation in the immediate and early postoperative period after temporal posterior limbal phacoemulsification and intraocular lens (IOL) implantation. Setting: Ambulatory surgical center. Methods: This prospective analysis comprised 310 eyes that had temporal posterior limbal phacoemulsification with IOL implantation. Surgical parameters included keratome incision of 2.85 mm, incision length of 2.5 mm, peribulbar anesthesia, case-completion IOP of 20 mm Hg, and postoperative lid taping. The IOP measurements were collected preoperatively and 30 minutes and 1 day after surgery. Results: Nineteen eyes (6.1%) had an IOP lower than 5 mm Hg 30 minutes postoperatively in the absence of incision leakage at the paracentesis or keratome sites. Eighteen of the 19 eyes with postoperative hypotony received hydroxypropyl methylcellulose 2% (OcuCoat) and 1 received hypromellose 2% (Cellugel). None of the 23 eyes with an acrylic IOL implanted via a cylindrical lens inserter had an IOP lower than 5 mm Hg postoperatively. Suturing did not significantly affect the incidence of hypotony, and there were no postoperative complications related to hypotony. The mean IOP at 30 minutes was lower than at 1 day in the normal, glaucoma, and glaucoma-suspect groups. Twenty-one normal eyes (8.1%), 5 glaucoma eyes (15.6%), and 1 glaucoma-suspect eye (5%) had an IOP greater than 30 mm Hg 1 day postoperatively. Conclusions: Postoperative hypotony (IOP <5 mm Hg) occurred in 19 (6.1%) of 310 eyes. At 1 day, IOP higher than 30 mm Hg was more frequent in glaucoma eyes than in normal eyes. Although there were no direct problems related to hypotony at 30 minutes or to elevated IOP (>30 mm Hg) at 1 day, surgeons should be aware of and check for IOP variability (low and high) that can occur in normal, glaucoma, and glaucoma-suspect eyes within the first 24 hours after surgery. [Copyright &y& Elsevier]

We counted fecal pellets of snowshoe hares (Lepus americanus) once a year in 10 areas in the southwestern Yukon from 1987 to 1996. Pellets in eighty 0.155-m[sup 2] quadrats were counted and cleared each June on all areas, and we correlated these counts with estimates of absolute hare density obtained by intensive mark–recapture methods in the same areas. There is a strong relationship between pellet counts and population density (r = 0.76), and we present a predictive log–log regression to quantify this relationship, which improves on our previously published 1987 regression, particularly at low hare densities. The precision of density estimates can be improved most easily by increasing the number of sets of quadrats in an area (one set = 80 plots), rather than increasing the number of plots counted within one set. The most important question remaining concerns the generality of this relationship for snowshoe hares living in other habitats in the eastern and southern portions of their geographic range.Nous avons compté les boulettes fécales de Lièvres d'Amérique (Lepus americanus) une fois l'an en 10 zones du sud-ouest du Yukon, de 1987 à 1996. Les boulettes ont été comptées chaque juin, puis retirées, dans quatre-vingt quadrats de 0,155 m[sup 2] dans chacune des zones; par la suite, ces nombres ont été mis en corrélation avec des estimations de la densité absolue des lièvres obtenues par des méthodes intensives de capture–recapture dans les mêmes zones. Il y a une forte corrélation entre le nombre de boulettes et la densité de la population (r = 0,76) et nous présentons ici une régression log–log prédictive pour quantifier cette relation, ce qui rend plus robuste la régression que nous avons publiée en 1987, particulièrement lorsque la densité des lièvres est faible. La précision des estimations de la densité peut être raffinée davantage en augmentant le nombre d'ensembles de quadrats dans une région (1 ensemble = 80 parcelles), plutôt que le nombre de parcelles dans chaque ensemble. Il reste à déterminer à quel point cette relation est généralisée chez les lièvres qui vivent dans d'autres habitats dans les portions est et sud de leur répartition.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Presents a report on common dynamic structure of Canada lynx populations within three climatic regions, namely Pacific-maritime, Continental, and Atlantic-maritime. Suggestion of a possible link with the North Atlantic Oscillation.