bluuebunny/crossref_metadata_2025_split huggingface dataset:
Endoscopic transventricular positioning of intracystic catheter for treatment of craniopharyngioma
Authors: Pettorini Benedetta L. , Tamburrini Gianpiero , Massimi Luca , Caldarelli Massimo , Di Rocco Concezio 
Published: September 2009

The intracystic injection of chemo- and radiotherapeutic agents was introduced for the treatment of craniopharyngioma to control tumor growth and to delay the potentially harmful effects of surgery or radiation therapy. The positioning of cyst catheters has been performed by means of direct vision, stereotactically guided insertion, and ultrasonographic and ventriculoscopic guidance. The insertion of a catheter into the cyst is not devoid of complications, with an incidence ranging up to 16%, independent of the surgical technique used.
Eight patients (mean age 25.8 years) with symptomatic cystic craniopharyngioma were treated by means of an endoscopic transventricular approach for the insertion of an intracystic catheter for intratumoral therapy with interferon-α.
A single right precoronal bur hole is made, and the frontal horn of the lateral ventricle is accessed under neuronavigation guidance. A ventricular catheter with an inserted stylet was advanced anterior to the endoscope sheath through the same cortical access as the endoscope and was guided under endoscopic view down to the cyst dome wall. The coagulated surface of the craniopharyngioma cyst was punctured and the tip of the ventricular catheter was advanced; the depth was established preoperatively on MR scans and confirmed by neuronavigation guidance. The proximal end of the cystic catheter was connected to an access chamber to be left in the subcutaneous space, and the endoscope was slowly retracted.
The authors' experience favors the use of neuroendoscopic positioning of intracystic catheters as safer than open and stereotactic approaches.
Quantification of Everest region glacier velocities between 1992 and 2002, using satellite radar interferometry and feature tracking
Authors: Quincey D.J. , Luckman A. , Benn D. 
Published: September 2009

AbstractMany glacier snouts in the Himalaya are known to be stagnant and exhibiting low surface gradients, conditions that are conducive to the formation of glacial lakes impounded either by the terminal moraine or by the remnant glacier snout. In this study, we use interferometry and feature-tracking techniques to quantify the extent of stagnation in 20 glaciers across the Everest (Qomolangma; Sagarmatha) region, and subsequently we examine the relationship between local catchment topography and ice dynamics. The results show that only one of the studied glaciers, Kangshung Glacier, is dynamic across its entire surface, with flow rates greater than 40 m a−1 being recorded in high-elevation areas. Twelve other glaciers show some evidence of flow, but are generally characterized by long, stagnant tongues, indicating widespread recession and in situ decay. The remaining seven glaciers show no evidence of flow in any of the available datasets. Hypsometric data suggest that catchment topography plays an important role in controlling glacier flow regimes, with those fed by wide, high-altitude accumulation areas showing the most extensive active ice, and those originating at low elevations exhibiting large areas of stagnant ice. Surface profiles extracted from a SRTM digital elevation model indicate that stagnant snouts are characterized by very low (<2°) surface angles and that down-wasting is the prevalent ablation pattern in the study area.
Influence of High-Dose Cortisol on the Biomechanics of Incubated Porcine Corneal Strips
Authors: Spoerl Eberhard , Zubaty Viktoria , Terai Naim , Pillunat Lutz E. , Raiskup Frederik 
Published: September 2009

Purpose:To investigate the change in biomechanical properties of the cornea induced by high-dose hydro-cortisone.Methods:The influence of hydrocortisone was investigated in 12 fresh porcine corneas incubated in culture medium of 2.5 µM of hydrocortisone for 7 days. Twelve additional porcine corneas incubated in culture medium without hydrocortisone for the same time served as the control group. Strips of cornea were cut and the stress–strain relationship was measured in a biomaterial tester. Young's modulus was calculated.Results:After incubation, the thickness of the cornea was 1120±130 µm in the control group and 1320±90 µm in the hydrocortisone group. The hydrocortisonetreated corneas were 18% thicker compared to the control corneas. However, the difference in the biomechanical stress value at 10% strain was significantly larger. In the control group, the stress value measured 122±40 kPa, and in the hydrocortisone group, it measured 77±19 kPa (P=.003), representing a reduction of the corneal stiffness by 37% due to hydrocortisone treatment. Young's modulus was reduced by 42.8% from 2.90±1.10 MPa in the control group to 1.66±0.49 in the hydrocortisone group.Conclusions:Hydrocortisone is a modulating factor of the biomechanical properties of the cornea. The significance of the cortisol status of the patient and its influence on the biomechanical stability of the cornea should be considered in the development of keratectasia in keratoconus or after refractive surgery. [J Refract Surg. 2009;25:S794–S798.]
In Vitro Antimicrobial Efficacy of Riboflavin and Ultraviolet Light onStaphylococcus aureus, Methicillin-resistantStaphylococcus aureus, andPseudomonas aeruginosa
Authors: Schrier Amilia , Greebel Gennifer , Attia Hosam , Trokel Stephen , Smith Edward F. 
Published: September 2009

Purpose:Ultraviolet (UV) light and riboflavin has been developed as a collagen cross-linking treatment for corneal ectasia. This treatment has also been used to treat infectious corneal ulcers with apparent favorable results. In this experiment, the antibacterial action of riboflavin alone, UV light alone, and the combination of riboflavin and UV light was tested onStaphylococcus aureus, methicillin-resistantS aureus(MRSA), andPseudomonas aeruginosa.Methods:Thirty agar plates withS aureusoverlays were used. Ten plates were exposed to riboflavin (0.1% solution in dextran) alone, 10 plates were exposed to UV light (365 nm) alone, and 10 plates were exposed to a combination of riboflavin and UV light. Fifteen agar plates with MRSA and 15 plates withP aeruginosawere tested. Five plates of each group were exposed to riboflavin, 5 plates of each group were exposed to UV light alone, and 5 plates of each group were exposed to a combination of riboflavin and UV light. All plates were incubated for 24 hours and then analyzed.Results:All plates exposed to riboflavin alone showed no bacterial death. AllS aureusand MRSA plates exposed to UV light alone showed no bacterial growth. Three of fiveP aeruginosaplates exposed to UV light alone showed no bacterial death; two of fiveP aeruginosaplates exposed to UV light alone showed minimal inhibition. All plates exposed to the combination of riboflavin and UV light showed bacterial death.Conclusions:Riboflavin in combination with UV light is an effective modality to eradicate the bacteriaS aureus, MRSA, andP aeruginosa. [J Refract Surg. 2009;25: S799–S802.]
Keratitis and Corneal Scarring After UVA/Riboflavin Cross-linking for Keratoconus
Authors: Koppen Carina , Vryghem Jérôme C. , Gobin Laure , Tassignon Marie-José 
Published: September 2009

Purpose:
To report four cases of severe keratitis after standard corneal collagen cross-linking (CXL) treatment for keratoconus.

Methods:

Four patients with progressive keratoconus from two different centers were treated by ultraviolet A (UVA) CXL, using riboflavin as a photosensitizer. The epithelium was removed over the central 8 to 9 mm of the cornea. Riboflavin 0.1% in dextran 20% was instilled every 2 minutes for 30 minutes before UVA exposure. The UV-X™ light source (IROC), calibrated at 3 mW/cm
2
, was applied for 30 minutes while instillation was continued every 2 minutes. At the end of the treatment, a bandage contact lens was applied and topical treatment consisting of a combination of antibiotics and/or anti-inflammatory drops was initiated.

Results:
Patients experienced delayed (after more than 24 hours) symptoms and signs of inflammation. The eyes showed pronounced ciliary redness with cells in the anterior chamber and central keratic precipitates; multiple white infiltrates had developed at the edge and within the area of CXL. High-dose topical or subconjunctival corticosteroids led to rapid initial improvement of symptoms and signs. Herpes virus could not be detected on the ocular surface or on the anterior chamber tap of one patient.

Conclusions:

We report four cases of keratitis and corneal scarring from a total of 117 eyes treated with CXL. The location of the scarring determined the amount of loss of visual acuity: in two eyes, there was a persistent decrease in best spectacle-corrected visual acuity. [
J Refract Surg
. 2009;25:S819–S823.]
Permanent Corneal Haze After Riboflavin-UVA-induced Cross-Linking in Keratoconus
Authors: Raiskup Frederik , Hoyer Anne , Spoerl Eberhard 
Published: September 2009

Purpose:
Retrospective evaluation of haze development after riboflavin-ultraviolet (UV) A-induced corneal collagen cross-linking (CXL).

Methods:
One hundred sixty-three eyes of 127 patients with stage 1–3 keratoconus according to Krumeich's classification were included in this retrospective analysis. Follow-up was 1 year. Preoperatively and at all follow-up examinations uncorrected visual acuity, best spectacle-corrected visual acuity (BSCVA), slit-lamp microscopic findings, corneal topography, and corneal thickness were recorded.

Results:

At 1 year after CXL, 149 (91.4%) eyes of 114 patients had a clear cornea without stromal haze (control group), whereas 14 eyes (8.6%) of 13 patients developed clinically significant stromal haze (haze group). Preoperatively, the mean keratometry (K) value of the apex was 62.1±13.8 diopters (D) in the control group and 71.1±13.2 D in the haze group (
P
=.02). The mean corneal thickness before the procedure was 478.1±52.4 µm in the control group and 420.0±33.9 µm in the haze group (
P
=.001). Uncorrected visual acuity and BSCVA, which were similar between groups preoperatively (
P
=.59 and
P
=.75, respectively), were improved in the control group (
P
=.023 and
P
=.001, respectively), but reduced in the haze group (
P
=.012 and
P
=.004, respectively) postoperatively.

Conclusions:

The parameters defining the stage of keratoconus, such as K-value and corneal thickness, could be considered predicting factors for possible development of corneal haze after riboflavin-UVA-induced CXL. Advanced keratoconus should be considered at higher risk of haze development after CXL due to low corneal thickness and high corneal curvature. [
J Refract Surg
. 2009;25:S824–S828.]
Reproducibility of Tear Meniscus Measurement by Fourier-Domain Optical Coherence Tomography: A Pilot Study
Authors: Zhou Sheng , Li Yan , Lu Ake Tzu-Hui , Liu Pengfei , Tang Maolong , Yiu Samuel C. , Huang David 
Published: September 2009

Background and Objective:
To study the reproducibility of tear meniscus measurement with high-speed high-resolution Fourier-domain optical coherence tomography (FD-OCT).

Patients and Methods:
Twenty normal participants were enrolled in this prospective study. The lower tear meniscus in the right eye of each subject was imaged by vertical scans centered on the inferior cornea and the lower eyelid using an FD-OCT system (RTVue; Optovue, Inc., Fremont, CA) with a corneal adaptor. The system performs 26,000 axial scans per second and has a 5-micron axial resolution. Each subject was examined at two visits 30 to 60 days apart. Each eye was scanned twice on each visit. The scans were taken 2 seconds after a blink. The lower meniscus height, depth, and cornea–meniscus angle were measured with a computer caliper. The cross-sectional area was calculated using a two-triangle approximation.

Results:
The between-visits coefficient of variation was 17.5%, 18.0%, 35.5%, and 12.2% for meniscus height, depth, area, and angle, respectively. The intraclass correlations for these parameters were 0.605, 0.558, 0.567, and 0.367, respectively.

Conclusion:
FD-OCT measures lower tear meniscus dimensions and area with higher between-visits reproducibility than previous OCT instruments. FD-OCT may be a useful way to measure dry eye severity and treatment effectiveness.

[Ophthalmic Surg Lasers Imaging 2009;40:442–447.]
Effectiveness of Laser Photocoagulation in Clinically Significant Macular Edema With Focal Versus Diffuse Parafoveal Thickening on Optical Coherence Tomography
Authors: Barkmeier Andrew J. , Nicholson Benjamin P. , Akduman Levent 
Published: September 2009

Background and Objective:
To evaluate whether increased foveal thickness in clinically significant diabetic macular edema responds differently to modified focal/grid laser photocoagulation in the setting of focal versus diffuse parafoveal thickening as defined by optical coherence tomography (OCT) criteria.

Patients and Methods:
The medical records of patients undergoing macular laser procedures for clinically significant diabetic macular edema were retrospectively reviewed. OCT, demographic, and clinical data were recorded for 62 consecutive eyes with clinically significant diabetic macular edema and foveal thickening (> 230 microns). Diffuse parafoveal thickening was defined as having all four parafoveal OCT quadrants greater than 300 microns, whereas focal thickening was defined as having fewer than four quadrants greater than 300 microns.

Results:

Mean foveal thickness decreased from 331 to 311 microns with relatively stable visual acuity (20/54 vs 20/51) after a single laser treatment session. The diffuse parafoveal edema subgroup (24 eyes) had a mean foveal thickness change from 383 to 366 microns (
P
= .47) and mildly decreased visual acuity (20/62 vs 20/69). The focal parafoveal edema subgroup (38 eyes) experienced statistically significant foveal thinning from 299 to 276 microns (
P
= .018) and mildly improved visual acuity (20/48 to 20/43).

Conclusion:

Increased foveal thickening associated with clinically significant diabetic macular edema responds more favorably to modified focal/grid laser photocoagulation in the setting of focal parafoveal edema by OCT criteria. Statistically significant foveal thinning occurred following treatment in the focal group (
P
= .018) but not the diffuse group (
P
= .47). Furthermore, eyes with focal parafoveal edema experienced a more beneficial visual acuity response than those with diffuse edema (
P
= .049).

[Ophthalmic Surg Lasers Imaging 2009;40:472–479.]
Definition of Implanted Neurological Device Abandonment
Authors: Okun Michael S. , Marjenin Timothy , Ekanayake Jinendra , Gilbert Frederic , Doherty Sean P. , Pilkington Jack , French Jennifer , Kubu Cynthia , Lázaro-Muñoz Gabriel , Denison Timothy , Giordano James 
Published: April 2024

ImportanceEstablishing a formal definition for neurological device abandonment has the potential to reduce or to prevent the occurrence of this abandonment.ObjectiveTo perform a systematic review of the literature and develop an expert consensus definition for neurological device abandonment.Evidence ReviewAfter a Royal Society Summit on Neural Interfaces (September 13-14, 2023), a systematic English language review using PubMed was undertaken to investigate extant definitions of neurological device abandonment. Articles were reviewed for relevance to neurological device abandonment in the setting of deep brain, vagal nerve, and spinal cord stimulation. This review was followed by the convening of an expert consensus group of physicians, scientists, ethicists, and stakeholders. The group summarized findings, added subject matter experience, and applied relevant ethics concepts to propose a current operational definition of neurological device abandonment. Data collection, study, and consensus development were done between September 13, 2023, and February 1, 2024.FindingsThe PubMed search revealed 734 total articles, and after review, 7 articles were found to address neurological device abandonment. The expert consensus group addressed findings as germane to neurological device abandonment and added personal experience and additional relevant peer-reviewed articles, addressed stakeholders’ respective responsibilities, and operationally defined abandonment in the context of implantable neurotechnological devices. The group further addressed whether clinical trial failure or shelving of devices would constitute or be associated with abandonment as defined. Referential to these domains and dimensions, the group proposed a standardized definition for abandonment of active implantable neurotechnological devices.Conclusions and RelevanceThis study’s consensus statement suggests that the definition for neurological device abandonment should entail failure to provide fundamental aspects of patient consent; fulfill reasonable responsibility for medical, technical, or financial support prior to the end of the device’s labeled lifetime; and address any or all immediate needs that may result in safety concerns or device ineffectiveness and that the definition of abandonment associated with the failure of a research trial should be contingent on specific circumstances.
Prescription and Dispensation of QT-Prolonging Medications in Individuals Receiving Hemodialysis
Authors: Wang Virginia , Wang Chin-Hua (Lily) , Assimon Magdalene M. , Pun Patrick H. , Winkelmayer Wolfgang C. , Flythe Jennifer E. 
Published: April 2024

ImportanceIndividuals with dialysis-dependent kidney failure have numerous risk factors for medication-related adverse events, including receipt of care by multiple clinicians and initiation of some QT-prolonging medications with known risk of torsades de pointes (TdP), which is associated with higher risk of sudden cardiac death. Little is known about the prescription and dispensation patterns of QT-prolonging medications among people receiving dialysis, hindering efforts to reduce drug-related harm from these and other medications in this high-risk population.ObjectiveTo examine prescription and dispensation patterns of QT-prolonging medications with known TdP risk and selected interacting medications prescribed to individuals receiving hemodialysis.Design, Setting, and ParticipantsThis cross-sectional study included patients 60 years or older who were enrolled in Medicare Parts A, B, and D receiving in-center hemodialysis from January 1 to December 31, 2019. Analyses were conducted from October 20, 2022, to June 16, 2023.ExposuresNew-user prescriptions for the 7 most frequently filled QT-prolonging medications characterized by the timing of the new prescription relative to acute care encounters, the type of prescribing clinician and pharmacy that dispensed the medication, and concomitant use of selected medications known to interact with the 7 most frequently filled QT-prolonging medications with known TdP risk.Main Outcomes and MeasuresThe main outcomes were the frequencies of the most commonly filled and new-use episodes of QT-prolonging medications; the timing of medication fills relative to acute care events; prescribers and dispensing pharmacy characteristics for new use of medications; and the frequency and types of new-use episodes with concurrent use of potentially interacting medications.ResultsOf 20 761 individuals receiving hemodialysis in 2019 (mean [SD] age, 74 [7] years; 51.1% male), 10 992 (52.9%) filled a study drug prescription. Approximately 80% (from 78.6% for odansetron to 93.9% for escitalopram) of study drug new-use prescriptions occurred outside of an acute care event. Between 36.8% and 61.0% of individual prescriptions originated from general medicine clinicians. Between 16.4% and 26.2% of these prescriptions occurred with the use of another QT-prolonging medication. Most potentially interacting drugs were prescribed by different clinicians (46.3%-65.5%).Conclusions and RelevanceIn this cross-sectional study, QT-prolonging medications for individuals with dialysis-dependent kidney failure were commonly prescribed by nonnephrology clinicians and from nonacute settings. Prescriptions for potentially interacting medications often originated from different prescribers. Strategies aimed at minimizing high-risk medication-prescribing practices in the population undergoing dialysis are needed.
Accuracy of Event Rate and Effect Size Estimation in Major Cardiovascular Trials
Authors: Olivier Christoph B. , Struß Lasse , Sünnen Nathalie , Kaier Klaus , Heger Lukas A. , Westermann Dirk , Meerpohl Joerg J. , Mahaffey Kenneth W. 
Published: April 2024

ImportanceFor the design of a randomized clinical trial (RCT), estimation of the expected event rate and effect size of an intervention is needed to calculate the sample size. Overestimation may lead to an underpowered trial.ObjectiveTo evaluate the accuracy of published estimates of event rate and effect size in contemporary cardiovascular RCTs.Evidence ReviewA systematic search was conducted in MEDLINE for multicenter cardiovascular RCTs associated with MeSH (Medical Subject Headings) terms for cardiovascular diseases published in the New England Journal of Medicine, JAMA, or the Lancet between January 1, 2010, and December 31, 2019. Identified trials underwent abstract review; eligible trials then underwent full review, and those with insufficiently reported data were excluded. Data were extracted from the original publication or the study protocol, and a random-effects model was used for data pooling. This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guideline. The primary outcome was the accuracy of event rate and effect size estimation. Accuracy was determined by comparing the observed event rate in the control group and the effect size with their hypothesized values. Linear regression was used to determine the association between estimation accuracy and trial characteristics.FindingsOf the 873 RCTs identified, 374 underwent full review and 30 were subsequently excluded, resulting in 344 trials for analysis. The median observed event rate was 9.0% (IQR, 4.3% to 21.4%), which was significantly lower than the estimated event rate of 11.0% (IQR, 6.0% to 25.0%) with a median deviation of −12.3% (95% CI, −16.4% to −5.6%; P &amp;lt; .001). More than half of the trials (196 [61.1%]) overestimated the expected event rate. Accuracy of event rate estimation was associated with a higher likelihood of refuting the null hypothesis (0.13 [95% CI, 0.01 to 0.25]; P = .03). The median observed effect size in superiority trials was 0.91 (IQR, 0.74 to 0.99), which was significantly lower than the estimated effect size of 0.72 (IQR, 0.60 to 0.80), indicating a median overestimation of 23.1% (95% CI, 17.9% to 28.3%). A total of 216 trials (82.1%) overestimated the effect size.Conclusions and RelevanceIn this systematic review of contemporary cardiovascular RCTs, event rates of the primary end point and effect sizes of an intervention were frequently overestimated. This overestimation may have contributed to the inability to adequately test the trial hypothesis.