The course of surface deposits on a hydrophilic acrylic intraocular lens after implantation through a hexagonal cartridge

AIM

To evaluate the outcome of surface deposits that occurred during implantation of hydrophylic acrylic intraocular lenses (IOLs) through a hexagonal cartridge.

METHODS

Surface deposits were observed on the posterior surface of the ACR6D SE IOLs that were injected through a hexagonal cartridge filled with sodium hyaluronate 1%. All the patients were examined 1 day, 1 week, 1 month, 6 months and 1 year postoperatively. The location of the deposits was recorded and photographed. The patients were questioned about blurred vision, glare or halos.

RESULTS

Linear or curly deposits were detected on the posterior surface of the IOL in six patients. In four patients, the deposits were peripheral and were observed 1 week postoperatively. In two patients, the deposits were noticed immediately after implantation. In one eye, they were misinterpreted as a crack in the IOL's optic and were left in the eye. In the second patient the deposits were removed immediately after implantation with forceps. The deposits that were left after implantation (five eyes) did not resolve during 1 year of follow-up. None of the eyes developed abnormal inflammatory reaction. In three eyes the best-corrected visual acuity (BCVA) was 6/6. In the other three eyes the BCVA was 6/12. None of the patients experienced any visual disturbance.

CONCLUSIONS

Implantation of the ACR6D SE IOL through a hexagonal cartridge can lead to the formation of deposits on the posterior surface of the lens. The deposits do not resolve and may resemble a crack in the IOL. The deposits left on the IOL had no clinical relevance in our patients.

Small plot trials documenting effective mating disruption of oriental fruit moth by using high densities of wax-drop pheromone dispensers

In 2004 field experiments, we compared the effectiveness of various deployment densities of 0.1-ml paraffin wax drops containing 5% pheromone versus Isomate M-Rosso "rope" dispensers for disruption of Grapholita molesta (Busck). Treatments were evaluated in 0.05-ha (12-tree) plots of 'Delicious' apples receiving regular maintenance according to growers' standards, but not sprayed with insecticides. The application densities of 0.1-ml wax drops were 3 per tree (820/ha), 10 per tree (2,700/ha), 30 per tree (8,200/ha), and 100 per tree (27,300/ha). Wax drops were compared with 3-ml dispensers of pheromone-containing paraffin wax or Isomate M-Rosso ropes at 1.8 per tree (500/ha) and untreated control plots. Treatments were applied before the start of each of three moth generations. Orientational disruption, as measured by inhibition of moth captures in pheromone-baited delta traps, was greatest in plots that received 100 drops per tree (99.2%) and 30 drops per tree (99.4%). More than 55% of tethered, virgin females were mated in control plots after one night of deployment. However, no mating was recorded at the two highest application densities of wax drops where orientational disruption of traps exceeded 99%. Mating ranged from 7 to 20% among the other treatments, including Isomate rope dispensers. G. molesta males were observed closely approaching pheromone dispensers in plots containing ropes and wax drops, documenting competitive attraction between synthetic pheromone sources and feral females. The majority of observed G. molesta males approached within 60 cm of wax drops or pheromone ropes and departed within 20 s by flying upwind. Thirty wax drops per tree yielded higher mating disruption of G. molesta than did Isomate M-Rosso dispensers deployed at the recommended rate of 500/ha (1.8 per tree). Measurement of release rates confirmed behavioral data indicating that paraffin wax dispensers would need to be applied once per G. molesta generation in Michigan. Paraffin wax drops are a promising technology for moth mating disruption. They are cheaper and easier to produce, require less total pheromone per annual application, and produce better mating disruption at appropriate deployment densities compared with Isomate M-Rosso dispensers under high G. molesta population densities. The cost-effectiveness of this approach will require an appropriate mechanized applicator for wax drops.

Clinical effectiveness, tolerability and cost-effectiveness of newer drugs for epilepsy in adults: a systematic review and economic evaluation

OBJECTIVES

To examine the clinical effectiveness, tolerability and cost-effectiveness of gabapentin (GBP), lamotrigine (LTG), levetiracetam (LEV), oxcarbazepine (OXC), tiagabine (TGB), topiramate (TPM) and vigabatrin (VGB) for epilepsy in adults.

DATA SOURCES

Electronic databases. Internet resources. Pharmaceutical company submissions.

REVIEW METHODS

Selected studies were screened and quality assessed. Separate analyses assessed clinical effectiveness, serious, rare and long-term adverse events and cost-effectiveness. An integrated economic analysis incorporating information on costs and effects of newer and older antiepileptic drugs (AEDs) was performed to give direct comparisons of long-term costs and benefits.

RESULTS

A total of 212 studies were included in the review. All included systematic reviews were Cochrane reviews and of good quality. The quality of randomised controlled trials (RCTs) was variable. Assessment was hampered by poor reporting of methods of randomisation, allocation concealment and blinding. Few of the non-randomised studies were of good quality. The main weakness of the economic evaluations was inappropriate use of the cost-minimisation design. The included systematic reviews reported that newer AEDs were effective as adjunctive therapy compared to placebo. For newer versus older drugs, data were available for all three monotherapy AEDs, although data for OXC and TPM were limited. There was limited, poor-quality evidence of a significant improvement in cognitive function with LTG and OXC compared with older AEDs. However, there were no consistent statistically significant differences in other clinical outcomes, including proportion of seizure-free patients. No studies assessed effectiveness of AEDs in people with intellectual disabilities or in pregnant women. There was very little evidence to assess the effectiveness of AEDs in the elderly; no significant differences were found between LTG and carbamazepine monotherapy. Sixty-seven RCTs compared adjunctive therapy with placebo, older AEDs or other newer AEDs. For newer AEDs versus placebo, a trend was observed in favour of newer drugs, and there was evidence of statistically significant differences in proportion of responders favouring newer drugs. However, it was not possible to assess long-term effectiveness. Most trials were conducted in patients with partial seizures. For newer AEDs versus older drugs, there was no evidence to assess the effectiveness of LEV, LTG or OXC, and evidence for other newer drugs was limited to single studies. Trials only included patients with partial seizures and follow-up was relatively short. There was no evidence to assess effectiveness of adjunctive LEV, OXC or TPM versus other newer drugs, and there were no time to event or cognitive data. No studies assessed the effectiveness of adjunctive AEDs in the elderly or pregnant women. There was some evidence from one study (GBP versus LTG) that both drugs have some beneficial effect on behaviour in people with learning disabilities. Eighty RCTs reported the incidence of adverse events. There was no consistent or convincing evidence to draw any conclusions concerning relative safety and tolerability of newer AEDs compared with each other, older AEDs or placebo. The integrated economic analysis for monotherapy for newly diagnosed patients with partial seizures showed that older AEDs were more likely to be cost-effective, although there was considerable uncertainty in these results. The integrated analysis suggested that newer AEDs used as adjunctive therapy for refractory patients with partial seizures were more effective and more costly than continuing with existing treatment alone. Combination therapy, involving new AEDs, may be cost-effective at a threshold willingness to pay per quality-adjusted life year (QALY) greater than 20,000 pounds, depending on patients' previous treatment history. There was, again, considerable uncertainty in these results. There were few data available to determine effectiveness of treatments for patients with generalised seizures. LTG and VPA showed similar health benefits when used as monotherapy. VPA was less costly and was likely to be cost-effective. The analysis indicated that TPM might be cost-effective when used as an adjunctive therapy, with an estimated incremental cost-effectiveness ratio of 34,500 pounds compared with continuing current treatment alone.

CONCLUSIONS

There was little good-quality evidence from clinical trials to support the use of newer monotherapy or adjunctive therapy AEDs over older drugs, or to support the use of one newer AED in preference to another. In general, data relating to clinical effectiveness, safety and tolerability failed to demonstrate consistent and statistically significant differences between the drugs. The exception was comparisons between newer adjunctive AEDs and placebo, where significant differences favoured newer AEDs. However, trials often had relatively short-term treatment durations and often failed to limit recruitment to either partial or generalised onset seizures, thus limiting the applicability of the data. Newer AEDs, used as monotherapy, may be cost-effective for the treatment of patients who have experienced adverse events with older AEDs, who have failed to respond to the older drugs, or where such drugs are contraindicated. The integrated economic analysis also suggested that newer AEDs used as adjunctive therapy may be cost-effective compared with the continuing current treatment alone given a QALY of about 20,000 pounds. There is a need for more direct comparisons of the different AEDs within clinical trials, considering different treatment sequences within both monotherapy and adjunctive therapy. Length of follow-up also needs to be considered. Trials are needed that recruit patients with either partial or generalised seizures; that investigate effectiveness and cost-effectiveness in patients with generalised onset seizures and that investigate effectiveness in specific populations of epilepsy patients, as well as studies evaluating cognitive outcomes to use more stringent testing protocols and to adopt a more consistent approach in assessing outcomes. Further research is also required to assess the quality of life within trials of epilepsy therapy using preference-based measures of outcomes that generate cost-effectiveness data. Future RCTs should use CONSORT guidelines; and observational data to provide information on the use of AEDs in actual practice, including details of treatment sequences and doses.

The UK Endovascular Aneurysm Repair (EVAR) Trials: Design, Methodology and Progress

OBJECTIVES

The endovascular aneurysm repair (EVAR) trials aim to assess the efficacy of EVAR in the treatment of AAA in terms of mortality, quality of life, durability and cost-effectiveness.

DESIGN

Male and female patients aged at least 60 years with an AAA diameter measuring at least 5.5 cm on a computed tomography (CT) scan are assessed for anatomical suitability for EVAR. Suitable patients are offered entry either into EVAR Trial 1 if they are considered fit for conventional open repair or EVAR Trial 2 if they are considered unfit. EVAR 1 randomly allocates patients to EVAR or open repair and EVAR 2 randomly allocates patients to EVAR with best medical treatment or best medical treatment alone. Target recruitment for EVAR Trials 1 and 2 is 900 and 280 patients, respectively.

PROGRESS

Recruitment began in September 1999 and there are currently 40 UK centres participating in the trials. Monthly targets are being exceeded in EVAR Trial 1 with 1037 patients randomised by October 2003. EVAR Trial 2 is also meeting monthly targets with a total of 319 patients randomised. When recruitment closes in December 2003 patients will need to be followed for at least 1 year from their operation. Publication of full results for both trials is expected in mid 2005.

The clinical course of acquired complete heart block in children with acute myocarditis

A case of biopsy-proven myocarditis in a 7-year-old complicated by advanced atrioventricular (AV) block prompted a review of the medical literature to determine the prognosis for recovery of AV conduction or need for pacemaker implantation. A total of 40 patients younger than 20 years of age were identified, with return of AV conduction within 7 days in 27 patients (67%), permanent pacing in 11 patients (28%) with persistent AV block, and death in 2 patients (5%).

A comparative assessment of endothelium from pseudophakic and phakic donor corneas stored in organ culture

AIMS

To evaluate the endothelial quality of corneas obtained from pseudophakic donors and to compare the data with matched phakic controls.

METHODS

Corneas from eyes with posterior chamber intraocular lenses (PCIOLs) and corneas from phakic eyes (controls) were stored for 1-2 weeks in organ culture and then examined after staining with Alizarin red S. The corneas were divided into two groups according to the duration of storage. Endothelial cell density, the percentage of hexagonal cells, and the coefficient of variation (CV) were determined.

RESULTS

There was no statistically significant difference between the 14 PCIOL corneas and the 13 controls stored in organ culture for 7 days for any of the three parameters studied. The mean cell density was 2155 (SD 529) cells/mm(2) in the PCIOL corneas and 2118 (453) cells/mm(2) in the controls (p=0.85). The mean percentage of hexagonal cells was 52% (8%) and 58% (7%), respectively (p=0.06). The mean CV was 0.32 (0.18) in the pseudophakic corneas and 0.39 (0.18) in the controls (p=0.33). Moreover, there was no significant difference between the PCIOL corneas and the controls stored for up to 2 weeks.

CONCLUSIONS

The corneal endothelium from eyes with PCIOLs appears to be similar to that of phakic eyes after 1-2 weeks in organ culture. This finding suggests that corneas from pseudophakic eyes should not routinely be disqualified for transplantation. The use of at least some pseudophakic corneas may substantially increase the potential donor pool.

Therapeutic drug monitoring in methadone maintenance: choosing a matrix

Methadone maintenance is the premier pharmacological treatment for opioid addiction, but it is rarely informed by evidence-based practice guidelines for dosage monitoring and adjustment. Such guidelines are crucial because the pharmacokinetics of methadone vary greatly among patients, and this variation may account for differences in treatment outcome. We review the pharmacokinetics of methadone and factors that may alter it (including drug interactions, disease states, and idiosyncratic differences among patients). Also reviewed are prospects for therapeutic drug monitoring (TDM) of methadone in plasma, urine, sweat, and saliva. Due to its ease of collection and its presumed representation of the bioavailable free-fraction of methadone, saliva may be a promising matrix. However, saliva methadone concentrations are influenced by salivary pH, and future studies are needed to determine how to control for that. Administrative, medical, and social implications of methadone TDM are briefly discussed.

Medical complications of female genital mutilation

More than 130 million women are subjected to genital mutilation. Despite increasing efforts to reduce the practice, there are many obstacles to eliminating this 2,000-year-old practice, which is based on strong cultural traditions. As college health clinicians provide care to more international students from countries where female genital mutilation is performed, increased awareness and knowledge of the procedure will enable clinicians to understand and manage its complications. We report a case of obstructive uropathy resulting in hydronephrosis secondary to female genital mutilation and review the medical literature regarding this and other complications of genital mutilation "surgery."

A mutant Drosophila insulin receptor homolog that extends life-span and impairs neuroendocrine function

The Drosophila melanogaster gene insulin-like receptor (InR) is homologous to mammalian insulin receptors as well as to Caenorhabditis elegans daf-2, a signal transducer regulating worm dauer formation and adult longevity. We describe a heteroallelic, hypomorphic genotype of mutant InR, which yields dwarf females with up to an 85% extension of adult longevity and dwarf males with reduced late age-specific mortality. Treatment of the long-lived InR dwarfs with a juvenile hormone analog restores life expectancy toward that of wild-type controls. We conclude that juvenile hormone deficiency, which results from InR signal pathway mutation, is sufficient to extend life-span, and that in flies, insulin-like ligands nonautonomously mediate aging through retardation of growth or activation of specific endocrine tissue.

A quality measurement framework for managed care organizations

This article presents a framework for a quality measurement system and its corresponding principles for quality improvement within a managed care environment. The quality measurement system comprises four modes: quality assessment, comparison, improvement, and system evaluation. If these modes are to be effective, the measurement system must incorporate the following five principles: (a) maintain and continually improve the data systems, (b) develop and utilize sound methodology and valid indicators, (c) build a competent measurement team, (d) develop effective strategies for implementation, and (e) protect member confidentiality. This model is helpful in the ongoing development and testing of new measurement systems.

Adult patients with occult bacteremia discharged from the emergency department: epidemiological and clinical characteristics

To determine the epidemiological and clinical characteristics of patients who were discharged from the emergency department (ED) and subsequently proved to have bacteremia, we prospectively assessed all patients examined in the ED during an 18-month period from whose blood cultures a significant organism was isolated. Discharged patients were contacted and reevaluated. Two case-control studies were conducted, in which each study patient was matched with a total of 4 control patients. During the study period, 46,336 patients were examined in the ED; 78% were adults and 22% were children. Blood cultures were performed for 25% of the adult patients and for 44% of the children. Although the occurrence of occult bacteremia in patients who were discharged from the ED is 3.7 times more common in children than in adults, the absolute numbers of discharged adults and children with occult bacteremia are similar. Careful clinical assessment will not prevent discharge of some of these patients; however, these patients in general do well and can be safely recalled for reevaluation and complementation of therapy.

Dyspnea differentiation index: A new method for the rapid separation of cardiac vs pulmonary dyspnea

STUDY OBJECTIVE

To assess the utility of a new parameter in the differentiation of dyspnea of cardiac origin from dyspnea of pulmonary origin.

METHODS

The peak expiratory flow (PEF) rate and the partial pressure of oxygen in arterial blood (PaO(2)) were measured in 71 patients with the chief complaint of dyspnea. The patients were treated in the hospital, and the final diagnosis (cardiac or pulmonary) of the cause of dyspnea was made at discharge. We defined a new measure, the dyspnea differentiation index (DDI), as (PEF x PaO(2))/1,000. We performed a receiver operating characteristic (ROC) curve analysis of the data to define the measure that best distinguished cardiac from pulmonary dyspnea. The curves also allowed us to establish an optimal cut-off point to distinguish between cardiac and pulmonary dyspnea.

RESULTS

Patients with pulmonary dyspnea had a significantly lower mean PEF than patients with cardiac dyspnea (144 +/- 66 vs 267 +/- 97 L/min, respectively; p < 0.001). They also had a lower DDI than patients with cardiac dyspnea (8.4 +/- 4.0 vs 18.4 +/- 7.9 L-mm/min, respectively; p < 0.001). These two measures, PEF and DDI, also best distinguished pulmonary from cardiac dyspnea. PEF was able to diagnose the correct cause of dyspnea in 72% of patients, and DDI was correct in 79% of patients. This compares favorably to the performance of the emergency department physicians, who were able to predict the correct diagnosis in only 69% of patients.

CONCLUSION

These results demonstrate that the PEF by itself is useful in differentiating between cardiac and pulmonary causes of dyspnea, but that the calculation of DDI is superior in this regard.

Photorefractive keratectomy to correct myopic or hyperopic astigmatism with a cross-cylinder ablation

PURPOSE

To assess the efficacy and safety of a combined ablation of the steep and flat meridian to correct astigmatism with the excimer laser.

METHODS

Twenty-two eyes with myopic, mixed, or hyperopic astigmatism (mean preoperative spherical equivalent refraction -4.30 +/- 4.70 D [range, -12.50 to +1.50 D] and mean preoperative cylinder magnitude -3.40 +/- 1.40 D [range, -1.50 to -6.00 D]) underwent PRK with the Nidek EC-5000 excimer laser. The surgical strategy involved ablating half the amount of the cylinder (in diopters) along steepest meridian, the other half in a subsequent step along the flattest meridian; thereafter, the spherical equivalent was corrected.

RESULTS

Six months postoperatively, mean spherical equivalent refraction was -0.07 +/- 0.87 D and mean cylinder was -0.44 +/- 0.36 D. Mean spectacle-corrected visual acuity was 0.86 +/- 0.13 compared to 0.75 +/- 0.22 preoperatively. Mean corneal haze was 0.67 +/- 0.31. No patient lost 2 or more lines of spectacle-corrected visual acuity and there were no complaints about night halos or glare.

CONCLUSIONS

Unlike other ablation strategies, the cross-cylinder method creates a smooth transition (low dioptric gradient) between the treated and untreated cornea. This is achieved by first treating the cylinder and making the corneal surface spherical and then ablating the spherical component of the refractive error.

Algorithm to correct hyperopic astigmatism with the Nidek EC-5000 excimer laser

BACKGROUND

The efficacy of a new ablation algorithm for the correction of hyperopic astigmatism with the Nidek EC-5000 excimer laser was evaluated.

METHODS

Twenty-five eyes with mean preoperative hyperopia of +3.76 +/- 1.70 D and a mean hyperopic cylinder of 2.20 +/- 0.80 D underwent photorefractive keratectomy (PRK) using a new algorithm with the Nidek EC-5000 excimer laser (software version 3.0). The new algorithm differed from previous algorithms in that less tissue was removed for the same amount of diopters, and there was less of a dioptric gradient between the optical zone and the transition zone. Mean preoperative spectacle-corrected visual acuity was 0.8 +/- 0.09. Minimum follow-up was 6 months.

RESULTS

Mean postoperative spectacle corrected visual acuity (geometric mean) increased significantly to 0.89 +/- 0.1. The mean sphere decreased by 3.08 D and the mean cylinder by 1.60 D.

CONCLUSION

Hyperopic PRK using the Nidek EC-5000 excimer laser with this new algorithm for hyperopic astigmatism appears to be safe and effective.