The influence of eyelid pressure and eye contour factors on rigid corneal contact lens fitting

PURPOSE

This study aimed to investigate the impact of eyelid pressure (ELP) and eye contour factors on rigid corneal contact lens fitting.

METHODS

This prospective cross-sectional study involved 20 participants (one eye per person). Rigid corneal contact lenses with three different base curves were selected for each participant. The base curves were calculated according to the average keratometry value. The original value and its variations (+0.1 mm and - 0.1 mm) were considered. Eye contour factors, lens decentration under natural eye position (LD I) and full eyelid exposure (LD II), and lens vertical movement were taken by a Canon camera mounted on a digital slit lamp biomicroscope. Upper and lower ELPs were measured by a novel blepharo-tensiometer.

RESULTS

The mean values of LD I, LD II, and lens vertical movement significantly increased as the base curve increased (P＜0.001, ＜0.001, and = 0.005). Upper ELP was positively correlated with lens vertical movement of the three base curves (P = 0.047, 0.001, and 0.004). Furthermore, upper ELP (odds ratio [OR]: 1.039; 95 % confidence [CI]: 1.009-1.069; P = 0.009) and flat keratometry values (OR: 0.873; 95 % CI: 0.786-0.969; P = 0.011) independently influenced lens vertical movement.

CONCLUSIONS

ELP and base curve independently influenced rigid corneal contact lens fitting. Thus, ELP should be considered during rigid corneal contact lens fitting in clinical practice.

Process and Outcomes of Fitting Corneoscleral Profilometry-Driven Scleral Lenses for Patients With Ocular Surface Disease

OBJECTIVES

To assess the feasibility of obtaining cornea scleral profile (CSP) measurements using Scheimpflug imaging and report on the fitting process of free-form custom scleral lenses (SLs) for patients with ocular surface disease (OSD).

METHODS

This prospective study of patients fit with free-form SLs collected data on the following: demographics, indications for wear, corneal and scleral tomography, scan acquisition process, and SL fitting process.

RESULTS

Cornea scleral profile scans were acquired on 15 eyes of nine patients. Mean scan time for right eyes was 10.7, and 9.7 min for left eyes. A mean of 2.9 follow-up visits were required to complete SL fitting, with a mean of 2.1 lenses ordered. One eye did not tolerate lens wear, and one eye could not be fit using the CSP scan because of insufficient data. The initial lens ordered was dispensed at the first follow-up visit for seven of the remaining 13 eyes, all of which were ultimately fit successfully in free-form lenses.

CONCLUSIONS

In this study of profilometry-guided SL fitting for eyes with OSD and low magnitude corneal astigmatism, the number of lenses and follow-up visits required were similar to outcomes of previous studies that described the diagnostic approach to SL fitting. In addition, imaging technology does not negate the need for skilled clinical observation while fitting SLs.

Case Report: Remote Scleral Lens Fitting for High Toric Scleras in a Keratoconus Patient

SIGNIFICANCE

Technology plays a crucial role in customizing scleral lenses and improving lens alignment, especially in challenging scleral shapes. In addition, remote fitting technology allows optometrists to extend their expertise globally, empowering patients to access to customized lenses without travel expenses.

PURPOSE

The objective of this study was to document the difficulties encountered in fitting a scleral lens in a patient with keratoconus and pronounced scleral toricity. In addition, the study aimed to present the successful remote fitting achieved by using advanced technology.

CASE REPORT

An Irish male patient diagnosed with keratoconus exhibited high scleral toricity. Generally, keratoconus eyes often exhibit significant scleral asymmetry associated with cone decentration and disease severity. Improperly aligned scleral lenses can lead to regional changes in scleral shape, lens decentration, discomfort, and visual disturbances. Indeed, previous scleral lens fits were unsuccessful because of these issues. Corneoscleral profilometry was acquired in Ireland and then used in Italy to design customized lenses, which were then delivered to the patient's optometrist in Ireland. The first lenses designed and delivered demonstrated excellent overall performance without requiring adjustments.

CONCLUSIONS

This report highlights the importance of corneoscleral profilometry to increase efficiency and reduce lens reorders and chair time, and the remote fitting in overcoming barriers to accessing specialized lens fitting.

Novel deep learning approach to estimate rigid gas permeable contact lens base curve for keratoconus fitting

INTRODUCTION

Rigid gas permeable contact lenses (RGP) are the most efficient means of providing optimal vision in keratoconus. RGP fitting can be challenging and time-consuming for ophthalmologists and patients. Deep learning predictive models could simplify this process.

OBJECTIVE

To develop a deep learning model to predict the base curve (R0) of rigid gas permeable contact lenses for keratoconus patients.

METHODS

We conducted a retrospective study at the Rothschild Foundation Hospital between June 2012 and April 2021. We included all keratoconus patients fitted with Menicon Rose K2® lenses. The data was divided into a training set to develop the model and a test set to evaluate the model's performance. We used a U-net architecture. The raw matrix of anterior axial curvature in millimeters was extracted from Scheimpflug examinations for each patient and used as input for the model. The mean absolute error (MAE) between the prediction and the prescribed R0 was calculated. Univariate and multivariate analyses were conducted to assess the model's errors.

RESULTS

Three hundred fifty-eight eyes from 202 patients were included: 287 eyes were included in the training dataset, and 71 were included in the testing dataset. Our model's Pearson coefficient of determination (R2) was calculated at 0.83, compared to 0.75 for the manufacturer's recommendation (mean keratometry, Km). The mean square error of our model was calculated at 0.04, compared to 0.11 for Km. The predicted R0 MAE (0.16 ± 0.13) was statistically significantly different from the Km MAE (0.23 ± 0.23) (p = 0.02). In multivariate analysis, an apex center outside the central 5 mm region was the only factor significantly increasing the prediction absolute error.

CONCLUSION

Our deep learning approach demonstrated superior precision in predicting rigid gas permeable contact lens base curves for keratoconus patients compared to the manufacturer's recommendation. This approach has the potential to be particularly beneficial in complex fitting cases and can help reduce the time spent by ophthalmologists and patients during the process.

Average Scleral Lens Replacement Period at a Tertiary Care Hospital

OBJECTIVE

To evaluate the average scleral lens replacement period at a tertiary care hospital.

METHODS

Patients were identified retrospectively through electronic medical records. Inclusion criteria included scleral lens patients treated at the USC Department of Ophthalmology who had reordered a scleral lens at least once in one eye. Lens order histories were evaluated, and statistical analysis included a multivariable, mixed-methods, linear, regression model.

RESULTS

Two hundred fifty-one patients (120 men and 131 women; average age 57.1±17.4 years, range 9-93 years) and a total of 445 eyes (227 OD, 218 OS; 199 irregular corneas, 246 ocular surface disease) were included. The average replacement period for a scleral lens was 23.9±14.3 months (range 5-2,617 days). Patients with greater scleral lens experience had a statistically significant increase in their average scleral lens replacement period; for every one year of additional experience wearing scleral lenses, average replacement period increased by 30.7 days ( P =0.001). There was no statistically significant correlation between average scleral lens replacement period and sex, diagnosis, prior outside scleral lens treatment, lens brand, or lens diameter.

CONCLUSION

The average scleral lens replacement period in this patient cohort at a tertiary care hospital was 23.9±14.3 months (1.99±1.19 years). Further studies are needed to better understand the impact of scleral lens age on ocular health and vision. Certainly, proper scleral lens training and education are essential to ensure optimal lens condition and treatment outcomes.

Evidence of Contact Lenses for Vision Rehabilitation in Corneal Diseases: A Review

OBJECTIVES

To evaluate the efficacy and safety of contact lenses (CL) as a therapeutic option for patients affected by a corneal disease and to determinate which is the best lens modality for each disease.

METHODS

A literature review using PubMed was performed. All relevant articles published during the last 15 years have been included.

RESULTS

Various studies point to CL as the best therapeutic option for some corneal diseases and even as an alternative to surgery in some cases. After fitting, patients show an improvement in their functional vision and quality of life, in some cases being able to drive or work again.

CONCLUSIONS

There is a lack of scientific evidence to determine which lens modality is suitable for each corneal pathology. Currently, according to this review, the reason for choosing between the different options depends on the severity of symptoms, and it is worth mentioning that scleral lenses seem to be the best option in advanced stages of disease. However, the expertise of professionals is also an important factor at the time of choosing a particular CL modality. Standardized criteria are still necessary for correct selection of lens modality for a correct management of the disease.

The Comparison of Soft HydroCone (Toris K) Silicone Hydrogel and Rigid Gas-Permeable Contact Lenses in Patients With Posterior Microphthalmos

OBJECTIVE

To evaluate and compare soft HydroCone (Toris K) silicone hydrogel and rigid gas-permeable contact lenses (RGPCLs) in patients with posterior microphthalmos (PMs), for visual rehabilitation and comfort.

METHODS

The records of 11 patients who were followed up in our hospital with the diagnosis of PM and were fitted with both Toris K and RGPCLs in our contact lens department were reviewed retrospectively. Patient age, gender, axial length (AL), topographic keratometry (K) values and best-corrected visual acuity (BCVA) with both lens types and subjective lens comfort status were recorded.

RESULTS

A total of 22 eyes of 11 patients with a mean age of 20.9±11.1 years were included in the study. The mean AL were 16.01±0.1 and 15.9±0.2 mm in the right and left eyes, respectively. Mean K1 and K2 were 48.6±2.2 and 49.4±2.2 D, respectively. Mean logMAR BCVA of the 22 eyes before contact lens fitting was 0.63±0.56 with spectacle. After Toris K and RGPCLs fitting, mean logMAR BCVA were 0.43±0.20 and 0.35±0.25, respectively. Both lenses provided better visual acuity than spectacles; RGPCLs also provided significantly better visual acuity than HydroCone lens ( P <0.05). Eight of 11 patients (73%) had ocular discomfort with RGPLs, and there was no complaint with Toris K.

CONCLUSIONS

The corneal surfaces are steeper in patients with PMs than in normal population. For that reason, their vision should be rehabilitated by special design keratoconus lenses like Toris K and RGPCLs. Although vision rehabilitation seems better with RGPCLs, these patients prefer Toris K more because of discomfort.

Scleral lens prescription and management practices: Emerging consensus

PURPOSE

To describe international scleral lens prescription and management practices across multiple practice types.

METHODS

For this cross-sectional study, scleral lens practitioners were asked to complete an electronic survey that requested information about a single scleral lens patient. Data collected included practitioner demographics (practice type, country, years of experience) and patient indications for scleral lens wear, fitting process, lens design, and care products.

RESULTS

Data were collected for 259 patients (419 eyes). Most participants (60%) practiced in the US, 75% worked primarily in community practice, and 58% claimed more than 5 years' experience fitting scleral lenses. Indications for scleral lens wear were corneal irregularity (87%), ocular surface disease (9%), and uncomplicated refractive error (4%). During the fitting process, the mean (SD) number of lenses ordered was 2.4 (1.6) (range, 1-16 lenses) during 3.8 (2.4) visits (range, 1-18 visits). Of patients, 62% used a daily surfactant cleaner, 47% used hydrogen peroxide disinfection, and 67% used single-use vials of nonpreserved saline. Mean lens diameter was 16.2 (1.1) mm (range, 11.8-23.0 mm). The landing zones were spherical (64%), toric (26%), quadrant-specific (7%), and custom (3%) designs. Optical power was spherical in 70%, toric in 27%, and higher-order aberration correcting in 3% of lenses. Only 5 lenses had multifocal optics.

CONCLUSIONS

General consensus regarding prescribing patterns (lens design, wearing schedules, care products) between US vs non-US, community vs academic, and new vs established providers is reported in this study. Relatively low percentages of patients wearing lenses with advanced landing zones or optical designs suggest that these new options have not been widely adopted.

Trends in Scleral Lens Fitting Practices: 2020 Scleral Lenses in Current Ophthalmic Practice Evaluation Survey

OBJECTIVES

To explore trends in demographic characteristics of scleral lens (SL) practitioners and primary indications for SL fitting over 5 years.

METHODS

An online survey similar to the 2015 Scleral Lenses in Current Ophthalmic Practice Evaluation (SCOPE) study was designed and administered from November 8, 2019, through March 31, 2020, to attendees at two international contact lens meetings, members of the Scleral Lens Education Society, and participants in the 2015 SCOPE study. Practitioners reporting at least five completed SL fits were included in the analysis.

RESULTS

Of 922 respondents, 777 had fit at least five SLs: 63% from the United States (59 other countries were represented), findings similar to the 2015 survey, in which 799 respondents (72%) were US-based and 49 from other countries. Most practitioners were in community practice (76%) than academic practice (24%). In 2015, 64% were in community practice and 36% in academic practice. A median of 84% of SLs were fit for corneal irregularity, 10% for ocular surface disease, and 2% for uncomplicated refractive error. In comparison, the 2015 indications were 74%, 16%, and 10%, respectively. The median number of fits completed per practitioner was 100 (range, 5-10,000; mean [SD] 284 [717]; n=752). In 2015, the median was 36 (range, 5-3,600; mean [SD] 125 [299]; n=678).

CONCLUSIONS

The number of experienced SL practitioners is increasing, as is international representation. Most practitioners practice in community rather than academic settings. SLs continue to be primarily prescribed for corneal irregularity and are rarely used solely for correction of refractive error.

Benefits of Scleral Lens in the Management of Irregular Corneas and Dry Eye Syndrome After Refractive Surgery

OBJECTIVES

To evaluate the utility of the SPOT scleral lens (Oxygen Permeable Scleral Lens of Thonon; LAO, Thonon-les-Bains, France) in the management of the irregular cornea after refractive surgery.

METHOD

We included 19 patients (35 eyes) with irregular corneas after refractive surgery. Patients were fitted with scleral lenses after the failure of conventional contact lenses adaptation. The ophthalmologic examination included measurement of best-corrected visual acuity (BCVA), slitlamp examination, and evaluation of ocular aberrations (Objective Scattering Index [OSI] and higher-order aberration [HOA]).

RESULT

Scleral lens fitting increases significantly the BCVA from 0.33 (±0.25) to 0.08 (±0.13) LogMAR (P<0.001). There was also a significant decrease in Ocular Surface Disease Index from 66.2±22.8 to 42.4±18.9 (P<0.001). Ocular aberrations (OAs) are also significantly reduced by the scleral lenses, the mean OSI goes from 7.2 (±4.2) to 3.0 (±1.8) (P<0.001), OA from 2.58 (±1.34) to 1.98 μm (±2.31) (P=0.035), and HOA from 0.94 (±0.51) to 0.48 (±0.23) (P=0.0018).

CONCLUSION

Fitting with scleral lenses improves patients' optical and ocular surface problems. Scleral lens restores BCVA and the quality of life. Fitting with scleral lenses is an alternative to further surgery on these fragile eyes and is sometimes the only viable treatment option for the patient.

Glaucoma Prevalence and Glaucoma Surgical Considerations in Prosthetic Replacement of the Ocular Surface Ecosystem Device Use

OBJECTIVES

The purpose of this study was to identify patients with glaucoma and corneal/ocular surface disease who have been fit with Prosthetic Replacement of the Ocular Surface Ecosystem (PROSE; BostonSight, Needham, MA) devices and to understand the PROSE device fit experience in patients with glaucoma at Weill Cornell Medicine (WCM).

METHODS

This is a retrospective chart review of patients older than 18 years who underwent PROSE device fitting at WCM. Records were reviewed for demographic information and ophthalmic variables. Descriptive statistics were performed.

RESULTS

Between 2011 and 2017, 281 patients underwent PROSE device fitting at WCM, of whom 24 patients (8.5%) had a glaucoma diagnosis and 17 patients (6.0%) were identified as glaucoma suspect. Ocular surface disease was the most common indication for PROSE device wear (58.3%). Five patients had a history of incisional glaucoma surgery in the eye undergoing PROSE device fitting: three valved glaucoma drainage implants and two trabeculectomies. Three of these eyes were successfully fit with PROSE devices.

CONCLUSIONS

Patients fitted with Prosthetic Replacement of the Ocular Surface Ecosystem devices at WCM had a higher prevalence of glaucoma than in the general population. Among patients with incisional glaucoma surgery, PROSE device fitting was challenging, with a 40% failure rate.

Frugal Method of Notch Modification of Scleral Contact Lenses in the Setting of Complex Ocular Surface Anatomy

ABSTRACT

Scleral contact lenses (ScCLs) have gained popularity as a treatment of refractive errors in patients with complex anterior segment pathology. Patients with mechanical abnormalities of the ocular surface may be unsuccessful with traditional ScCL fitting. Scleral contact lens modifications, such as notching and microvaulting, typically incur additional financial costs and require the services of professional laboratories. We describe a frugal method of ScCL notch modification that can be performed by a practitioner using readily available tools in a single office visit. Two patients with abnormal ocular surface anatomy were fit with the practitioner-modified ScCL and achieved successful visual rehabilitation. We offer this method as a potentially economical and effective technique to achieve successful ScCL fitting in this challenging patient population with pathologies that may preclude standard ScCL usage.

Procedural Results of Patients Undergoing Transcatheter Aortic Valve Implantation With Aortic Annuli Diameter ≥26 mm: insights from the German Aortic Valve Registry

Patients presenting with severe aortic stenosis and large aortic annuli are challenging to treat because of the size limitations of available transcatheter heart valves. In this study, we aimed to determine clinical and hemodynamic outcomes in patients presenting with large aortic annuli who underwent transcatheter aortic valve implantation (TAVI). Patients from the German Aortic Valve Registry who underwent TAVI either with the Edwards Sapien (ES) or Medtronic CoreValve (MCV) systems from 2011 to 2017 were included. They were further stratified into a large (aortic annulus diameter 26 to 29 mm for ES; 26 to 30 mm for MCV) and extra-large (aortic annulus diameter >29 mm for ES; >30 mm for MCV) group and analyzed using propensity score adjustment. Extra-large was set beyond the sizing limitations according to the manufacturer's instructions for use. Patients in the large (n = 5,628) and extra-large (n = 509) groups were predominantly male (large: 92.6% vs extra-large: 91.9%). The 30-day mortality was comparable (large: 3.9% vs extra-large: 5.0%, p = 0.458). Procedure duration (large: 78.9 minutes ± 0.82 vs extra-large: 86.4 minutes ± 1.9, p <0.001) was longer in the extra-large group. Likewise, vascular complications (large: 6.2% vs extra-large: 12%, p = 0.002) and the need for a permanent pacemaker implantation (large: 18.8% vs extra-large: 26.0%, p = 0.027) were more often present in the extra-large group. Aortic regurgitation ≥II after valve implantation was numerically higher (large: 3.0% vs extra-large: 5.3%, p = 0.082) in patients with extra-large anatomy. In conclusion, patients with large and extra-large aortic annulus diameters who underwent TAVI have comparable 30-day mortality. Beyond the recommended annulus range, there is a higher risk for vascular complications and permanent pacemaker implantation.

Quality-of-Life Improvement After Scleral Lens Fitting in Patients With Keratoconus

OBJECTIVES

To assess the quality-of-life improvement after scleral lens fitting in patients with keratoconus.

METHODS

We conducted a prospective observational study of all consecutive patients with keratoconus starting scleral lens fitting in 2019, from January 2 to December 27, at the Dijon University Hospital, France. Quality of life was assessed before and after wearing scleral lenses for 3 months through the National Eye Institute Visual Function Questionnaire 25 (NEI-VFQ 25) questionnaire. We investigated factors potentially influencing quality of life: final visual acuity, keratoconus stage, and maximum keratometry reading.

RESULTS

In total, 41 eyes of 24 patients were successfully fitted with scleral lenses, 92.9% were 18 mm in diameter and 7.1% were 17 mm. The visual acuity improved by -0.4±0.3 logarithm of the minimum angle of resolution (P<0.001) after scleral lens fitting. Visual gain increased with keratometry and keratoconus severity (P<0.001; P<0.01). The NEI-VFQ 25 score increased by 19.5±19.1 points on average (P<0.001). No association was found between the factors under study and improvement in quality of life.

CONCLUSION

Our study confirms the functional improvement in patients with keratoconus fitted with scleral lenses, especially in patients with more advanced disease. Moreover, it suggests a major role of these lenses in improving quality of life, independently of the severity of the disease and the visual gain.

Impact of Patient Prosthesis Mismatch on the Outcome of Transcatheter Pulmonic Valve Implantation

Patient prosthesis mismatch (PPM) is an important factor of the outcome in transcatheter aortic valve implantation. However, the impact of PPM in transcatheter pulmonic valve implantation (TPVI) has not been studied. Based on the narrowest valve stent diameters in two views of fluoroscopy, internal geometric orifice area (GOA) of the valve stent was calculated and indexed by body surface area (BSA), deriving iGOA. To define PPM in TPVI, receiver operating characteristics (ROC) curve analysis for iGOA for predicting significant residual right ventricular outflow tract (RVOT) gradient was used to derive the optimal cut-off value of iGOA. Our cohort were divided into 2 groups: PPM versus non-PPM. The clinical data were compared between 2 groups. TPVI was performed using Melody valve in 101 patients. Significant RVOT residual pressure gradient (≥ 15 mmHg) was observed in 31 patients (39.6%). Over a mean follow up periods of 6.9 ± 2.7 years, 22 patients (21.8%) required repeat interventions (16 transcatheter, 11 surgical, and both in 5 patients). Based on the ROC analysis, the best cut-off value of iGOA was 1.25 cm²/m² (area under the curve 0.873, p < 0.001) to define PPM. PPM was present in 42 patients (42%). On the Kaplan-Meier survival analysis, PPM was associated with the need of repeat intervention (p = 0.02). In conclusion, in TPVI, PPM was a strong predictor for the need of re-intervention. Considering PPM, target diameter of valve stent would depend on the patient body size and should be taken into account for optimal outcome of TPVI.

Visual Rehabilitation With Contact Lenses Following Open Globe Trauma

OBJECTIVES

To describe visual outcomes with various contact lens modalities in patients with a history of ocular trauma who underwent surgical open globe repair.

METHODS

Records of all patients with a history of open globe injury and repair at a tertiary care hospital between January 1, 2010, and December 31, 2016, were reviewed. Demographics, type of injury, and visual acuity were assessed before and after contact lens evaluation.

RESULTS

Of 214 patients who underwent open globe repair, 29 (13.6%) were evaluated with a contact lens. Visual acuity improved in 97% (28 of 29) of patients from 1.47±0.75 to 0.67±0.71 logarithm of the minimal angle of resolution (logMAR) with manifest refraction to 0.28±0.45 logMAR with contact lenses (n=29; P<0.0001). Corneal opacity was the most common clinical indication (20 of 29) for fitting followed by aphakia (13 of 29). A range of contact lens modalities, including corneal rigid gas-permeable (12 of 28), soft (9 of 28), hybrid (3 of 28), scleral gas-permeable (2 of 28), and piggyback (2 of 28) lenses were prescribed.

CONCLUSION

In this study, patients with a history of trauma and open globe repair with good neurosensory visual potential had improvements in visual acuity with contact lens greater than manifest refraction. Soft and gas-permeable lenses were used to improve visual acuity in patients with a history of open globe repair and corneal scarring, aphakia, iris abnormalities, or other ocular sequelae. Although corneal rigid gas-permeable lenses were prescribed most often, additional consideration should be given to other contact lens modalities, including soft, piggyback, hybrid, and scleral gas-permeable lenses.

Clinical Outcome of Hybrid Contact Lenses in Keratoconus

OBJECTIVES

To report the clinical outcome of hybrid contact lens fitting in keratoconus.

METHODS

A retrospective chart review was performed of keratoconus patients who had been fitted with hybrid contact lenses in one or both eyes. Patients with a history of previous intraocular surgery (except for corneal crosslinking) and relevant concurrent ocular disease limiting visual outcome were excluded. The outcome data at 6-month follow-up included hybrid lens-corrected visual acuity, wearing time, and lens discontinuation.

RESULTS

Fifty-four keratoconus patients (102 eyes) were included. Mean visual acuity with habitual correction before hybrid lens fitting was 0.63±0.29 (decimal Snellen). Eyes were fitted with Eyebrid lenses (LCS Laboratories, Caen, France) and SynergEyes lenses (SynergEyes Inc., Carlsbad, CA). Refits were necessary in 13 eyes, because of poor fitting (76.9%) or suboptimal refraction (23.1%). Visual acuity had significantly improved with hybrid lenses (0.93±0.14; P<0.0001). In 37 eyes (37.8%), hybrid lens wear was discontinued within 6 months after lens fitting. Reported issues were discomfort in 27 eyes (73%), handling difficulties in 14 eyes (37.8%) and poor vision in 1 eye (2.7%). Success rate of lens fitting was significantly correlated to cone morphology (P=0.01).

CONCLUSIONS

New generation hybrid lenses are an appropriate, safe therapeutic option for keratoconus patients. Excellent visual outcomes are achieved in successful fittings, yet a dropout rate of 37.8%-mainly occurring in sagging, more peripheral, cones - still limit their clinical success.

Use of silicone hydrogel contact lenses by Australian optometrists

BACKGROUND

Prior to the launch of silicone hydrogel (Si-H) materials in Australia in 1999, only 1.6 per cent of lenses were prescribed on a continuous wear basis.

METHODS

One thousand surveys were distributed randomly to practitioners in Australia during January 2000, 2001 and 2002 (total surveys 3000). Each anonymous survey requested data about the next 10 patients fitted with contact lenses, including date, age, gender, new fitting or refitting, lens material type, lens design, frequency of replacement, modality of wear, uses per week and care regimen.

RESULTS

Twenty per cent (599) were returned, reporting data on 5976 fittings. A total of 710 fittings used Si-H contact lenses (11.9 per cent), which represented 18.6 per cent of all soft lens fittings. During the three years, the proportion of practitioners prescribing Si-H lenses increased from 42.2 to 52.5 per cent. In 2000, 43.8 per cent were daily wear, which decreased to 32.2 per cent by 2002. The solution system of choice for daily wear lenses was multipurpose solutions (98.4 per cent); the only alternative was hydrogen peroxide systems. Continuous wear represented 11.7 per cent of all fittings, of which 85.7 per cent were Si-H, 3.0 per cent RGP lenses and 11.3 per cent conventional hydrogels. For continuous wear, 79.0 per cent of fittings were to existing wearers, whereas for daily wear, 59.4 per cent were existing wearers. More males were prescribed Si-H continuous wear contact lenses, while females were more likely to be prescribed Si-H on a daily wear basis.

DISCUSSION

Si-H contact lenses were introduced to the Australian market as a continuous wear contact lens, yet many practitioners use this product for daily wear with multipurpose solutions. By 2002, more practitioners were prescribing Si-H contact lenses for continuous wear than in 2000, suggesting a growing confidence in that product for that mode of wear. A comparison with an earlier survey shows there is an increase in continuous wear from 1.6 per cent to 11.7 per cent over a five-year period.

An evaluation of silicone‐hydrogel lenses worn on a daily wear basis

PURPOSE

To examine the clinical performance of two brands of silicone-hydrogel lenses when worn on a daily wear basis.

METHODS

Fifty-six subjects with no ocular disease were enrolled at multiple sites in Australasia. Contact lenses made from galyfilcon A or lotrafilcon A were randomly assigned to each eye of the subject and the lenses were worn on a daily wear basis for a period of two weeks. Subjects did not know the identity of the lenses they wore. Clinical data and patient responses to a questionnaire were gathered at an initial visit and after two weeks of wear.

RESULTS

For both lenses, the degree of limbal hyperaemia and bulbar conjunctival hyperaemia decreased significantly over the two-week wearing period. The eyes wearing galyfilcon A lenses showed an increase in conjunctival staining compared to the baseline measures. On average, galyfilcon A lenses decentred more and moved less than the lotrafilcon A lenses. The lotrafilcon A lenses showed a greater loss of wettability, as judged by practitioner grading, than the galyfilcon A lenses over the two-week period. The subjective responses showed strong preference for the galyfilcon A lens across 26 of 27 questions relating to comfort, vision, handling, preference and other subjective outcomes.

DISCUSSION

The results show that different silicone-hydrogel lenses have different performance characteristics on the eye, when worn on a daily wear basis. Striving for high oxygen transmissibility at the expense of other properties may lead to a range of undesirable performance characteristics.

Measurements of the local evoked potential from the cochlear nucleus in patients with an auditory brainstem implant and its implication to auditory perception and audio processor programming

The measurement of the electrically evoked compound action potential (ECAP) in cochlear implant (CI) patients is widely used to provide evidence of a functioning electrode-nerve interface, to confirm proper location of the electrode array and to program the sound processor. In patients with an auditory brainstem implant (ABI), a likewise versatile measurement would be desirable. The ECAP measurement paradigm “Alternating Polarity” was utilized to record responses via the implanted ABI electrode array placed on the cochlear nucleus. Emphasizing on the different location of stimulation and recording, these responses are called local evoked potentials (LEP). LEP measurements were conducted during the clinical routine in 16 ABI patients (12 children and 4 adults), corresponding to 191 electrode contacts. A retrospective analysis of these data revealed, that LEP responses were observed in 64.9% of all measured electrode contacts. LEP responses predicted auditory perception with a sensitivity of 90.5%. False-positive rate was 33.7%. Objective LEP thresholds were highly significantly (p < 0.001) correlated both to behavioral thresholds (Pearson’s r = 0.697) and behavioral most comfortable levels (r = 0.840). Therefore, LEP measurements have the potential to support fitting in ABI patients.

Contact Lens Adaption in Neophytes

SIGNIFICANCE

Clinicians commonly either recommend patients begin contact lens (CL) wear full time or suggest that patients should gradually increase their wear times during the first few days of wear. This study found no differences between these two wear schedules, suggesting that patient preference may be the best schedule.

PURPOSE

The purpose of this study was to determine if there are any clinical differences in neophyte, 2-week, reusable soft CL wearers who were randomized to either a full-time or a gradually increasing wear time schedule.

METHODS

This was an investigator-masked, three-visit, randomized, clinical trial. Participants were randomized to wear their CLs full time starting on the first day or gradually starting with 2 hours of wear on the first day and increasing wear by 2 hours each day until 8 hours or more of wear per day was achieved. Symptoms (Ocular Surface Disease Index and visual analog scale) and ocular surface signs (tear breakup time, extent of corneal staining, and Schirmer test I) were evaluated at each visit.

RESULTS

A total of 25 participants were randomized, with 21 participants completing at least 1 week of follow-up. Completed participants had a mean ± standard deviation age of 23.5 ± 3.0 years, and 48% were female. No significant between-group differences were found when comparing the full-time and gradual wear time schedule groups at 2 weeks (all, P > .32): Ocular Surface Disease Index (10.8 ± 8.5 vs. 16.3 ± 18.8), visual analog scale (89.0 ± 9.7 vs. 81.8 ± 18.7), tear breakup time (11.7 ± 7.0 vs. 9.8 ± 2.7), extent of corneal staining (0.0 ± 0.1 vs. 0.3 ± 0.5), or Schirmer test I (15.9 ± 8.8 vs. 21.2 ± 12.5).

CONCLUSIONS

No between-group differences were found for any metric evaluated, which suggests that the best wear schedule may be the one that best suits the neophyte CL wearer's lifestyle.

Visual Performance of Center-distance Multifocal Contact Lenses Fit Using a Myopia Control Paradigm

PURPOSE

The purpose of this study was to examine the visual performance of center-distance MFCLs in nonpresbyopic adults under different illumination and contrast conditions compared with a single-vision contact lens (SVCL).

METHODS

Twenty-five adult subjects were fit with three different lenses (CooperVision Biofinity D MFCL +2.50 add, Visioneering Technologies NaturalVue MFCL, CooperVision Biofinity sphere). Acuity and reading performance were evaluated.

RESULTS

A statistically significant difference in high-contrast distance acuity was observed (Biofinity, -0.18 ± 0.06; Biofinity MFCL, -0.14 ± 0.08; NaturalVue MFCL, -0.15 ± 0.03; repeated-measures [RM] ANOVA, P = .02). Under mesopic, high-contrast conditions, MFCLs performed worse than SVCLs (Biofinity, -0.05 ± 0.091; Biofinity MFCL, +0.03 ± 0.09; NaturalVue MFCL, +0.05 ± 0.091; RM-ANOVA, P < .0001). Under low-contrast conditions, MFCLs performed one line worse in photopic lighting and two lines worse under mesopic conditions (RM-ANOVA, P < .0001). Glare reduced acuity by 0.5 logMAR for all lenses (RM-ANOVA, P < .001). A statistically significant difference in near acuity was observed (RM-ANOVA, P = .02), but all lenses achieved acuity better than -0.1 logMAR (Biofinity, -0.16 ± 0.06; Biofinity MFCL, -0.17 ± 0.04; NaturalVue MFCL, -0.13 ± 0.08). Reading performance in words per minute (wpm) was worse with MFCLs (Biofinity MFCL, 144 ± 22 wpm; NaturalVue MFCL, 150 ± 28 wpm) than with SVCLs (156 ± 23 wpm; RM-ANOVA, P = .02) regardless of letter size (RM-ANOVA, P = .13). No difference in acuity between the MFCLs was detected (RM-ANOVA: all, P > .05).

CONCLUSIONS

Multifocal contact lenses perform similarly to SVCLs for high-contrast targets and display reduced low-contrast acuity and reading speed. Practitioners should recognize that high-contrast acuity alone does not describe MFCL visual performance.

Gas-Permeable Contact Lenses and Water Exposure: Practices and Perceptions

SIGNIFICANCE

This study provides insight into the current recommendations, clinical behaviors, and risk assessments of eye care professionals on the topic of rigid contact lens exposure to tap water. This knowledge may motivate professional organizations to develop initiatives to educate eye care professionals on the dangers of contact lens exposure to water.

PURPOSE

The purpose of this study was to investigate the practice patterns and risk perceptions of eye care professionals regarding gas-permeable contact lens exposure to tap water.

METHODS

A branched-logic survey was started by 320 clinicians, vision scientists, and industry personnel and was fully completed by 272 participants. The survey queried participants about their current practices, recommendations, and perceptions of risk regarding exposure of gas-permeable contact lenses to tap water.

RESULTS

Of those who prescribe gas-permeable contact lenses, 57.4% reported rinsing lenses with tap water, whereas only 32.7% reported engaging in this same behavior in front of patients. Of those who reported never rinsing lenses with tap water, 85.6% indicated that rinsing lenses with water increases infection risk, whereas 52.1% of those who rinse lenses with water reported the same perceived risk (P < .001). Of all participants, 60% indicated that wearing contact lenses while showering increases infection risk, and 50.2% of all participants advised patients to avoid this behavior.

CONCLUSIONS

A discrepancy exists between perceptions of risk concerning exposure of contact lenses to water and both clinical practices and patient education provided by professionals.

A novel, low-cost transradial socket fabrication method using mass-producible components and expanding rigid foam

BACKGROUND

Millions of people in low- and middle-income countries lack access to prosthetic care. A well-fitting, durable socket is important for prosthesis comfort and function, but conventional fabrication techniques require highly trained clinicians and specialized equipment.

OBJECTIVES

To increase access to prosthetic care by developing a simple, low-cost socket fabrication method that does not require specialized equipment or electricity, and can be performed by persons with minimal prosthetic training.

STUDY DESIGN

Socket fabrication methods and socket function were evaluated in a pilot feasibility study.

TECHNIQUE

We describe a rapid method for fabricating a rigid foam socket directly over the residual limb, with a mass producible, strong, cosmetically appealing plastic outer shell. We fabricated sockets for four individuals with unilateral transradial amputations and evaluated socket function.

RESULTS

An individual with no formal prosthetic training was able to fabricate sockets and assemble a functional, comfortable prosthesis system within 90 min. All necessary supplies can be provided in a kit for under US$100.

DISCUSSION

Further work is required to determine durability, assess comfort, refine suspension methods, and to develop instructional materials.

CONCLUSIONS

We developed a simplified, inexpensive method to fabricate sockets on the residual limb using expandable foam with an integrated cosmetic/structural covering (i.e. an exoskeletal system), for persons with transradial amputation. A transradial prosthesis socket can be fabricated in around 90 min. and all necessary materials, tools, and written instructions for fabrication and fitting can be provided in a kit. Specialized equipment and electricity are not required. Instructions for fabrication and fitting can be provided in multiple languages using online videos.

Clinical guidelines for the management of keratoconus patients with gas permeable contact lenses based on expert consensus and available evidence

PURPOSE OF REVIEW

Fitting rigid gas permeable contact lenses (RGP CLs) in keratoconic patients is the most common visual rehabilitation option to improve patients' quality of life, but require long patient and practitioner chair time. The purpose of this review is to provide evidence-based clinical practice guidelines (CPG) in the management of patients with keratoconus with RGP CLs.

RECENT FINDINGS

An extensive literature review from 1990 to 2017 identified 354 potentially relevant publications. Fifty-two articles were reviewed and included in the CPG. An international expert panel of eight contact lens practitioners, with vast experience in keratoconus management reviewed and appraised the CPG following the Appraisal of Guidelines for Research and Evaluation II consortium requirements. The developed CPG clearly outlines a strategy for the successful fitting of RGP CLs in patients with keratoconus. This includes how to calculate parameters of the first diagnostic lens, criteria for assessing good fit and a standardized schedule of wear time and follow-up appointments.

SUMMARY

The current evidence and consensus-based CPG helps guide clinicians in a successful strategy for fitting RGP CLs in patients with keratoconus.

Current perspectives in the management of keratoconus with contact lenses

Our aim is to review current and significant articles on contact lens wear in keratoconus patients. A comprehensive literature search of PubMed was performed for the following topics on contact lens wear in keratoconus patients: (1) characteristics of contact lens wearers, (2) safety and efficacy, (3) complications, (4) fitting techniques, (5) contact lens wear after procedures/surgeries, (6) patient satisfaction. A total of 104 studies were finally selected and reviewed. Gas permeable (GP) lens wear provided significantly better vision than glasses. Special cone design lenses had better patient comfort levels though there was no difference in best corrected visual acuity among the GP lenses. Soft lenses showed good efficacy for the treatment of mild-to-moderate keratoconus with newer designs improving visual performance such as customised hydrogel and novel pinhole lenses. Scleral and hybrid lenses provide good visual acuity and comfort for keratoconic patients previously intolerant to RGP lenses. RGP lens wear post-cross linking (CXL) is relatively well-tolerated. Contact lenses may still be required post intrastromal corneal ring procedures and post keratoplasty. Scheimpflug imaging and anterior segment optical coherent tomography (ASOCT) are useful in contact lens fitting. Computerized contact lens fitting techniques could reduce the chair time of lens fitting as well as improve comfort and visual performance. Contact lenses play an important role in the visual rehabilitation of keratoconus patients. New contact lens designs and materials have significantly expanded the available fitting options for keratoconus patients. Imaging technology can be utilized to guide contact lens fitting.

[Rotationplasty in a schoolboy for osteosarcoma: Prosthesis fitting and update]

INTRODUCTION

The classical treatment of osteosarcoma used to be ablative surgery. After the appearance of adjuvant chemotherapy, survival in these patients increased, and with it, the number of affected school age children with high growth potential. Hence, reconstructive surgeries are currently proposed instead of conventional bone resections due to greater limb preservation and better functional status than those achieved with conventional amputations.

CASE PRESENTATION

We describe a case of osteosarcoma in a 9-year-old boy with a history of retinoblastoma. The tumour involved the entire length of the left femur. He also had a lung metastasis. Given the incomplete response to neoadjuvant chemotherapy, we chose bone resection, rotation and fitting of the left lower limb and thoracoscopy to treat the lung injury. A bypass ortoprosthesis was placed for the first 6 weeks, until there was healing, bone consolidation and absence of complications, followed by a definitive orthoprosthesis for the next 4 months. At one year, the patient was able to walk independently with the use of the ortoprosthesis, swimming with a fin adapted to the stump and was had restarted cycling. At the last clinical review, at the age of 13 years, he is disease free and continues to have periodic follow-up visits in our office for adaptations to the prosthesis according to his growth.

DISCUSSION

This case highlights the various reconstructive options available and the difficulties encountered in the management of these aggressive malignant processes. Rotationplasty is a viable therapeutic option in young patients with osteosarcoma, which allows the child to participate again in premorbid daily and recreational activities.

Balloon Filling Algorithm for Optimal Size of Balloon Expandable Prosthesis During Transcatheter Aortic Valve Replacement

Aim is to report on the results of an optimized balloon filling algorithm and suggest a refinement of the implantation approach to maximize safety. Appropriate sizing of balloon expandable valves during transcatheter aortic valve implantation is crucial. Study comprised 370 consecutive patients receiving SAPIEN 3 valve between 2015 and 2018. Valve expansion/recoil measurement in the inflow area, annular area, and outflow area was performed previously and postimplantation. Nominal balloon filling resulted in underexpansion-23 mm (20.96 mm), 26 mm (23.88 mm), and 29 mm (27.56 mm) SAPIEN 3 valves at the annular level. Increased balloon filling by 2 cc resulted in a gradual increase in valve diameter reaching 97.35% (23 mm), 96.50% (26 mm), and 96.11% (29 mm) of the nominal valve diameter. Final diameters were usually higher in the valvular inflow and outflow tracts. The 29 mm valve did not reach its nominal diameter with 2 cc overfilling and in none of inflow area (95.48%), annular area (96.11%), or outflow area (96.86%). Device success (by VARC II) was 96.2%. No root or septal rupture, device migration, mitral valve injury, coronary obstruction, or dissection occurred. Rate of new permanent pacemaker implantation was 8.3%. Paravalvular leakage was none or trace in most patients. Mean valve gradient was 10.77 mm Hg postprocedure. 1.9% of the patients had a maximum gradient of >40 mm Hg, 2.2% >20 mm Hg. In conclusion, an optimized balloon filling algorithm resulted in appropriate valve gradients, low levels of paravalvular leakage, low rates of permanent pacemaker implantation and no annular rupture.

Chopart Amputation: Questioning the Clinical Efficacy of a Long-standing Surgical Option for Diabetic Foot Infection

BACKGROUND

Diabetic foot ulcers with associated infection and osteomyelitis often lead to partial or complete limb loss. Determination of the appropriate level for amputation based on the patient's baseline physical function, extent of infection, vascular patency, and comorbidities can be challenging. Although Chopart amputation preserves greater limb length than more proximal alternatives such as Syme or below-the-knee amputations (BKA), challenges with wound healing and prosthesis fitting have been reported. We aimed to investigate the functional and clinical outcomes of Chopart amputation combined with tendon transfers.

METHODS

We identified patients who underwent Chopart amputations for diabetic foot infections by an academic orthopaedic group between August 2013 and September 2018. Subjects completed three Patient-Reported Outcomes Measurement Information Systems (PROMIS) instruments. Incidence of postoperative complications and change in patient-reported outcomes before and after surgery were recorded.

RESULTS

Eighteen patients with an average age of 60.8 (range, 44 to 79) years were identified. The mean follow-up was 22.8 months (range, 6.7 to 51.0). Seventeen of the 18 total patients developed postoperative wound complications. These lead to revision amputations in 10 Chopart amputees, consisting of two Syme and eight BKAs. Half of the Chopart patients never received a prosthesis because of delayed wound healing and revision amputation. PROMIS physical function (PF) (31.1 pre-op and 28.6 post-op), pain interference (63.1 pre-op and 59.4 post-op), and depression (53.0 pre-op and 54.8 post-op) did not show significant change (P-values = 0.38, 0.29, 0.72, respectively). Pre- and post-op the PROMIS physical function scores were well below the US average.

DISCUSSION

In our patient cohort, 94% of patients developed postoperative wound complication. Only 44% of patients ever successfully ambulated with a prosthesis after Chopart amputation, and the others (56%) required revision amputations such as a BKA. Even after wound healing, Chopart amputees may struggle with obtaining a prosthesis suitable for ambulation. Surgeons should exercise judicious patient selection before performing Chopart amputation.

LEVEL OF EVIDENCE

IV, Case Series.

Performance of a Fully Adaptive Directional Microphone to Signals Presented from Various Azimuths

The signal-to-noise ratio advantage of a directional microphone is achieved by reducing the sensitivity of the microphone to sounds from the sides and back. A fully adaptive directional microphone (one that automatically switches between an omnidirectional mode and various directional polar patterns) may allow the achievement of signal-to-noise (SNR) improvement with minimal loss on audibility to sounds that originate from the sides and back. To demonstrate such possibilities, this study compared the soundfield aided thresholds, speech in quiet at different input levels, and speech in noise performance of 17 hearing-impaired participants under three microphone modes (omnidirectional, fixed hypercardioid, and fully [or automatic] adaptive) as the stimuli were presented from 0° to 180° in 45° intervals. The results showed a significant azimuth effect only with the fixed directional microphone. In quiet, the fully adaptive microphone performed similarly as the omnidirectional microphone at all frequencies, input levels, and azimuths. In noise, the fully adaptive microphone achieved similar SNR improvement as the fixed directional microphone. Clinical implications of the results of this study were discussed.

Problems and Solutions for Fitting Amplification to Patients with Ménière's Disease

Fitting amplification to a patient with Ménière's disease (MD) can present several challenges to the dispensing audiologist. These challenges include the presence of fluctuating hearing loss, a rising audiometric configuration, unilateral or asymmetrical hearing loss, reduced dynamic range, and reduced word-recognition scores. The presence of any one of these characteristics could create obstacles for a successful hearing aid fit. The presence of most if not all of these characteristics in a single patient can readily challenge the skills of even the most experienced dispensing audiologist. In addition to the audiometric challenges, this patient population has the added psychological problems associated with feeling ill due to the nausea secondary to vertiginous attacks and the anxiety associated with the unpredictable nature of the course of these attacks. This paper summarizes numerous strategies and technologies that could be implemented by the audiologist to address these unique challenges and provide a greater opportunity for a successful hearing aid fit. These suggestions include (1) advantages offered by digital signal processing; (2) using directional microphones and assistive listening devices to improve speech recognition in noise; (3) using wireless hearing aids as well as the bone anchored hearing aid; (4) counseling patients on the realistic expectations from amplification in noisy listening situations and for those with poor speech recognition; (5) using multiple programs for patients with fluctuating hearing loss; and (6) offering suggestions on programming the frequency-gain/output response for a rising configuration.

Short-Term and Long-Term Hearing Aid Benefit and User Satisfaction: A Comparison between Two Fitting Protocols

Currently published hearing aid fitting protocols recommend speech-in-noise testing and loudness measures, but it remains unclear how these measures affect hearing aid benefit and user satisfaction. This study compared two protocols in their effects on benefit and satisfaction. Protocol A included an electroacoustic analysis, real-ear measures, and hearing aid adjustments based on users' comments. Protocol B included all of Protocol A and a speech-in-noise test, loudness discomfort levels, and aided loudness. Thirty-two participants completed the Abbreviated Profile of Hearing Aid Benefit (APHAB) and the Satisfaction with Amplification in Daily Life (SADL) at 45 days and three months post–initial fitting. Fewer hearing aid adjustments were made to the hearing aids for participants fitted with Protocol B than participants fitted with Protocol A, but final gains were similar for both groups. Although similar APHAB scores were obtained for both protocols, SADL scores decreased between 45 days and three months for Protocol A. Los protocoles de amplificación de auxiliares auditivo actualmente publicados recomiendan pruebas de lenguaje en ruido y mediciones de apreciación subjetiva de la intensidad (sonoridad), pero no está claro cómo estas mediciones afectan el beneficio de un auxiliar auditivo y la satisfacción del usuario. El estudio comparó dos protocolos en cuanto a sus efectos sobre beneficio y satisfacción. El Protocolo A incluyó un análisis electroacústico, mediciones de oído real y ajuste en el auxiliar auditivo basados en los comentarios del usuario. El Protocolo B incluyó todas las pruebas del Protocolo A, además de una prueba de audición en ruido, de niveles de molestia en la apreciación subjetiva de la intensidad y de sonoridad amplificada. Treinta y dos participantes completaron el Perfil Abreviado de Beneficio del Auxiliar Auditivo (APHAB) y la prueba de Satisfacción con la Amplificación en la Vida Diaria (SADL) a los 45 días y a los tres meses de la adaptación inicial. Tuvieron que hacerse menos ajustes en el audífono en los auxiliares auditivos de participantes adaptados con el Protocolo B, que en los participantes adaptados con el Protocolo A, pero las ganancias finales fueron similares en ambos grupos. Aunque se obtuvieron puntajes APHAB similares en ambos protocolos, los puntajes SADL disminuyeron entre los 45 días y los tres meses para el Protocolo A.

A Digital Processing Strategy to Optimize Hearing Aid Outputs Directly

A new amplification strategy (ADRO™), based on 64 independently operating channels, was compared with a nine-channel wide dynamic range compression strategy (WDRC). Open-platform in-the-ear hearing instruments were configured either with ADRO or the manufacturer's WDRC strategy. Twenty-two subjects with mild to moderate hearing loss took home the ADRO or WDRC hearing aids. After three weeks' acclimatization, the aids were evaluated using monosyllables in quiet at 50 to 65 dB SPL and sentences in eight-talker babble. The acclimatization and evaluation were repeated in the second phase of the balanced reverse-block blind experimental design. The ADRO program showed a statistically significant mean advantage of 7.85% word score (95% confidence interval 3.19% to 12.51%; p = 0.002) and 6.41% phoneme score for the monosyllables in quiet (95% confidence interval 2.03% to 10.79%; p = 0.006). A statistically significant advantage of 7.25% was also found for the ADRO program in background noise (95% confidence interval 1.95% to 12.55%; p = 0.010). The results are consistent with earlier data for listeners with moderate to severe hearing loss.

The Relationship between Obligatory Cortical Auditory Evoked Potentials (CAEPs) and Functional Measures in Young Infants

Finding ways to evaluate the success of hearing aid fittings in young infants has increased in importance with the implementation of hearing screening programs. Cortical auditory evoked potentials (CAEP) can be recorded in infants and provides evidence for speech detection at the cortical level. The validity of this technique as a tool of hearing aid evaluation needs, however, to be demonstrated. The present study examined the relationship between the presence/absence of CAEPs to speech stimuli and the outcomes of a parental questionnaire in young infants who were fitted with hearing aids. The presence/absence of responses was determined by an experienced examiner as well as by a statistical measure, Hotelling's T2. A statistically significant correlation between CAEPs and questionnaire scores was found using the examiner's grading (rs = 0.45) and using the statistical grading (rs = 0.41), and there was reasonably good agreement between traditional response detection methods and the statistical analysis. La búsqueda de formas de evaluar el éxito de una adaptación de auxiliares auditivos en niños pequeños ha aumentado en importancia con la implementación de los programas de tamizaje auditivo. Se pueden registrar potenciales evocados auditivos corticales (CAEP) en infantes y aportar evidencia sobre la detección del lenguaje a nivel cortical. La validez de esta técnica como una herramienta para la evaluación de las necesidades de adaptación de auxiliares auditivos necesita, sin embargo, ser demostrada. El presente estudio examinó la relación entre la presencia/ausencia de CAEP ante estímulos de lenguaje y el resultado de un cuestionario a los padres de infantes a los que se adaptaron auxiliares auditivos. La presencia/ausencia de respuestas fue determinada por un examinador con experiencia, así como por un procedimiento de medición estadística: la T2 de Hotelling. Se encontró una correlación estadísticamente significativa entre los CAEP y los puntajes del cuestionario, utilizando la gradación del examinador (rs = 0.45) y utilizando la gradación estadística (rs = 0.41), y existió un acuerdo razonablemente bueno entre los métodos tradicionales de detección de respuesta y el análisis estadístico.

Measuring Hearing Aid Outcomes Using the Satisfaction with Amplification in Daily Life (SADL) Questionnaire: Australian Data

The aims of this study were to investigate hearing aid satisfaction for a group of older Australians fitted with government-funded hearing aids using the Satisfaction with Amplification in Daily Life (SADL) questionnaire; to compare the Australian data gathered with the provisional normative data reported by Cox and Alexander (1999); and to investigate the relationship between SADL satisfaction and several participant variables, hearing aid variables, and other outcome measures.

The SADL questionnaire and a Client Satisfaction Survey (CSS) were distributed by mail to 1284 adults fitted with government-funded hearing aids three to six months previously. 1014 surveys were returned. The mean age of participants was 75.32 years; 54.4% of participants were male, and 54.8% were fitted binaurally. Participants were fitted primarily with digitally programmable hearing aids of various styles (22.5% BTEs, 34.8% ITEs, 41.8% ITCs, 0.9% nonstandard [NS] devices).

Overall, participants reported a considerable level of satisfaction with their devices. SADL Global and subscale scores were significantly higher for the Australian sample than the U.S. norms described by Cox and Alexander (1999).

Evaluation of a Probe-Tube Insertion Technique for Measuring the Real-Ear-to-Coupler Difference (RECD) in Young Infants

A common strategy for measuring the real-ear response of the real-ear-to-coupler difference (RECD) in the pediatric population is to insert a probe-tube separately from the eartip. This strategy is at times difficult to implement while attempting to obtain the measurement from a young infant. An RECD probe-tube insertion technique that involves connecting the probe-tube to an eartip with plastic film for simultaneous insertion was examined on 30 infants. Repeated measurements were completed on each infant to obtain within-session test-retest reliability data. Probe-tube insertion depth was also examined across participants to provide a guideline for the infant population. Findings indicate that reliable RECD values can be obtained in infants when the probe-tube is extended approximately two to four millimeters (mm) beyond the eartip or 11 mm from the entrance to the ear canal. Clinical implications of this work are discussed.

Quantifying and Responding to Patient Needs and Expectations

Comprehensive audiometric testing serves as the cornerstone of adult hearing aid fittings for many clinicians. The data will serve to define the degree, configuration, and site of lesion of the hearing loss. The data will be used in prescriptive formula to preset the hearing aid and may be entered into probe microphone or hearing aid test box equipment to provide verification targets. Clinicians are comfortable obtaining audiometric data, have an accepted way of obtaining these data, and are comfortable discussing these data with patients and other professionals. The patient, however, is not a walking audiogram and may bring all sorts of interesting nuances to the process.

Just as part of the clinician's comfort with using audiometric data comes from the standard process of obtaining and reporting these data, the clinician who chooses to go beyond the audiogram in terms of data collection with a patient must have a means for gathering and quantifying additional information. The following case describes a method of obtaining and quantifying the patient's listening and communication needs. The case illustrates the use of these measures in recommending appropriate communication and safety solutions.

Analysis of Prefitting versus Postfitting Hearing Aid Orientation Using the Glasgow Hearing Aid Benefit Profile (GHABP)

Results of this study demonstrate the advantages of both pre- and postfitting hearing aid orientation (HAO) sessions. This study demonstrated that HAO counseling is helpful in expediting hearing aid benefit and satisfaction through the education of our clients and that this benefit and satisfaction is age dependent as measured by the Glasgow Hearing Aid Benefit Profile (GHABP) (Gatehouse, 1997). Patients with greater initial disability, as identified by item 1 of the GHABP, receive significant benefit from prefitting and/or postfitting counseling as compared to patients receiving no counseling. Implications of these findings are discussed.

NIDCD/VA Hearing Aid Clinical Trial and Follow-Up: Coupler and Real-Ear Measurement

A total of 190 individuals participated in a clinical visit during the Cooperative Studies Program (CSP) 418-A Long Term Follow-Up Study. Of this cohort, 158 participants were considered current hearing aid users, and 32 were non–hearing aid users. Of the current hearing aid users, 81 were still using their original 418 study devices, and 77 had acquired new hearing aids. Coupler and real ear measurements were completed on all available hearing aids. Results showed that study aids had remained relatively stable over the six years between CSP 418 and CSP 418-A. On average, these hearing aid wearers preferred use gain settings that were 6–9 dB less than current NAL-RP insertion gain targets. Mean real ear insertion gain (REIG) was comparable to the mean real ear insertion gain of the same participants in the original study, and users did not tend to increase gain as hearing decreased. Real ear saturation responses (RESR) remained unchanged. Loudness discomfort levels (LDL) obtained during 418-A were significantly lower than LDLs obtained on those same participants at both the initial and final visits in the previous study. Un total de 190 individuos participaron de la visita clínica durante el Estudio de Seguimiento a Largo Plazo 418-A del Programa de Estudios Cooperativos (CSP). De esta cohorte, 158 participantes se consideraron usuarios actuales de auxiliares auditivos (AA), y 32 se consideraron no usuarios de AA. De los usuarios actuales de AA, 81 aún utilizaban sus dispositivos 418 del estudio, y 77 había adquiridos nuevos AA. Se completaron mediciones de acoplador y de oído real para todos los AA disponibles. Los resultados mostraron que los AA del estudio había permanecido relativamente estables en los seis años entre el CSP 418 y el CSP 418-A. En promedio, estos usuarios de AA prefirieron el uso de ajustes de ganancia que estaban 6-9 dB por debajo de las metas actuales de ganancia de inserción del NAL-RP. La ganancia media de inserción de oído real (REIG) fue comparable con la ganancia media de inserción de oído real de los mismos participantes en el estudio original, y los sujetos no tendieron a incrementar la ganancia conforme la audición se deterioró. Las respuestas de saturación de oído real (RESR) se mantuvieron sin cambio. Los niveles de incomodidad a la intensidad subjetiva (LDL) obtenidos durante el 419-A fueron significativamente más bajos que los LDL obtenidos en los mismos participantes, tanto en la visita inicial como final del estudio previo.

The Effects of Expansion on the Objective and Subjective Performance of Hearing Instrument Users

The present study investigated the effects of expansion on the objective and subjective performance of 20 hearing instrument users fitted binaurally with digital ITE products. Objective performance was evaluated in quiet using the Connected Speech Test and in noise using the Hearing in Noise Test. Subjective performance was evaluated in two ways: (a) by having each participant rate their satisfaction regarding the amount of noise reduction they perceived in each expansion condition on a daily basis and (b) by having each participant indicate which expansion condition they preferred following the completion of a two-week trial. Results indicated that expansion significantly reduced low-level speech perception performance; however, satisfaction and preference ratings significantly increased when using expansion. The effect of degree of hearing loss, expansion kneepoint, and expansion ratio on the effectiveness of expansion for a given listener was discussed.

Gain and Maximum Output of Two Electromagnetic Middle Ear Implants: Are Real Ear Measurements Helpful?

We compared the output of two electronic middle ear implants: the Otologics MET™ device and the Vibrant Soundbridge™ device. Both devices were programmed in the linear amplification mode. Aided minus unaided sound pressure levels recorded in the ear canal (objective gain) were compared to unaided minus aided soundfield thresholds (functional gain) in 13 patients with severe sensorineural hearing loss. In addition, input/output characteristics were studied with the help of ear canal measurements. Objective gain was consistently lower than functional gain, with wide variation between patients and frequencies. Using input/output data measured in the ear canal in combination with functional gain data, the mean maximum output of the two devices was estimated, expressed in dB SPL. In comparison to NAL-R target values, (functional) gain was adequate; however, the maximum output was low, especially for the Vibrant Soundbridge device.

Fitting Hearing Aids Using Clinical Prefitting Speech Measures: An Evidence-Based Review

A systematic review of the literature addressed the question "Is there evidence of a good correlation between unaided prefitting speech measures and aided satisfaction on self-report measures?" This restricted question is only one of several possible questions related to speech measures and hearing aid fittings. The levels of evidence that were accepted included meta-analyses, randomized controlled trials, and nonrandomized intervention studies. Nearly 300 articles and book chapters were identified during the initial search; 220 were eliminated on the basis of their abstracts; and 80 papers and book chapters were reviewed in depth. Five studies met the criteria set forth in this review. No significant correlation between traditional unaided prefitting speech measures and aided satisfaction was found in any of the five studies. One of the studies showed a correlation between the results of a prefitting speech-in-noise test and self-reported aided satisfaction.

Field Evaluation of an Asymmetric Directional Microphone Fitting

Laboratory evidence suggests that an asymmetric microphone fitting (omnidirectional processing in one ear and directional processing in the other) can provide a directional advantage in background noise that is as great, or nearly as great, as that provided by binaural directional processing (Bentler et al, 2004). The present study investigated whether the potential benefit of an asymmetric fitting observed in the laboratory extends to real-life listening. Specifically, ease of listening was compared across a variety of real-life listening situations for asymmetric microphone fittings and bilateral omnidirectional processing. These ratings were compared to determine whether the asymmetric fitting provided an advantage in listening situations in which directional microphone processing is generally preferred and/or a disadvantage in listening situations in which omnidirectional microphone processing is generally preferred. Results suggest that an asymmetric fitting may be a viable option for patients who cannot or do not switch microphone modes. La evidencia de laboratorio sugiere que una adaptación asimétrica de micrófono (procesamiento omnidireccional en un oído y procesamiento direccional en el otro) puede aportar una ventaja direccional en medio de ruido de fondo que es tan buena, o al menos casi tan buena, como la otorgada por un procesamiento direccional biauricular (Bentler y col., 2004). El presente estudio investigó si el beneficio potencial de una adaptación asimétrica observada en el laboratorio se extiende a la audición en la vida real. Específicamente, la facilidad de escucha fue comparada en una variedad de situaciones auditivas en la vida real utilizando adaptaciones asimétricas de micrófono y de procesamiento omnidireccional bilateral. Estos resultados fueron comparados para determinar si la adaptación asimétrica aportaba una ventaja a la hora de escuchar, situaciones donde se suele preferir el procesamiento por micrófono direccional, y/o, una desventaja en situaciones auditivas donde se prefiere el procesamiento con micrófono omnidireccional. Los resultados sugieren que una adaptación asimétrica puede ser una opción viable para pacientes que no pueden o no quieren cambiar la modalidad de micrófono.

Undersized Stentgraft Placement for Traumatic Descending Aorta Rupture, and What Is Next?

BACKGROUND Traumatic injury of the thoracic aorta is proving to be not only the most lethal of traumatic injuries, but also the most urgent reason for vascular intervention among all trauma patients. Endovascular aortic repair is used increasingly often to treat traumatic injuries. We report a case of endovascular treatment and its use as a delayed correction (two-stage treatment) for a traumatic aortic isthmus rupture. CASE REPORT A 20-year-old Asian male was admitted to our department after a car accident presenting symptoms of ischemic shock. Among multiple injuries, a traumatic descending aorta rupture was diagnosed. The patient was referred directly to the operating room for a thoracic endovascular aortic repair (TEVAR). The patient's other trauma-related injuries required additional interventions in the following days. Thirty days after the emergent TEVAR operation, the patient required reintervention due to a major type-I endoleak. Computed tomography angiography revealed a failed stentgraft deployment. We removed the mismatched endovascular equipment and deployed an appropriately sized stentgraft during a hybrid procedure, excluding the ruptured aortic wall altogether. CONCLUSIONS Endovascular treatment of both children and small-framed adults remains a challenge for operating teams. First, no dedicated equipment can be found on the market. Second, measuring and fitting endovascular equipment constitutes a sore point in treatment, so in emergency situations, only off-the-shelf tools are accessible. We assert that, in such cases, the primary procedure should be understood as a lifesaving intervention, awaiting a final and long-lasting solution.

Effectiveness of elevated vacuum and suction prosthetic suspension systems in managing daily residual limb fluid volume change in people with transtibial amputation

BACKGROUND

Previous studies investigating limb volume change with elevated vacuum have shown inconsistent results and have been limited by out-of-socket volume measurements and short, single-activity protocols.

OBJECTIVES

To evaluate the effectiveness of elevated vacuum for managing limb fluid volume compared to suction suspension with an in-socket measurement modality during many hours of activity.

STUDY DESIGN

Fixed-order crossover design with a standardized out-of-laboratory activity protocol.

METHODS

Transtibial electronic elevated vacuum users participated in two sessions. Elevated vacuum was used during the first session, and suction suspension in the second. Participants completed a 5.5-h protocol consisting of multiple intervals of activity. In-socket residual limb fluid volume was continuously measured using a custom portable bioimpedance analyzer.

RESULTS

A total of 12 individuals participated. Overall rate of fluid volume change was not significantly different, though the rate of posterior fluid volume change during Cycle 3 was significantly lower with elevated vacuum. Although individual results varied, 11 participants experienced lower overall rates of fluid volume loss in at least one limb region using elevated vacuum.

CONCLUSION

Elevated vacuum may be more effective as a volume management strategy after accumulation of activity. Individual variation suggests the potential to optimize the limb fluid volume benefits of elevated vacuum by reducing socket vacuum pressure for some users.

CLINICAL RELEVANCE

A better understanding of how elevated vacuum (EV) affects residual limb fluid volume will allow prosthetists to make more informed clinical decisions regarding accommodation strategies designed to improve daily socket fit.

Experimental Model of Far Temporal Field Negative Dysphotopsia Generated in Phakic Eyes

Purpose

The axial separation between the iris and the intraocular lens (IOL) in pseudophakic eyes can cause rays originating from the far temporal field to miss the IOL, resulting in negative dysphotopsia (ND). We developed an experimental model to test the hypothesis that obstruction of rays from the far temporal field can generate ND and an accompanying loss of visual sensitivity in the far temporal field.

Methods

The right eyes of 10 phakic subjects were fitted with soft contact lenses containing a 5.50-mm central clear zone and a 12-mm outer diameter opaque annulus. In three of the subjects, eyes were dilated with 1% tropicamide solution, and effective aperture diameters were determined optically (pupil camera) and psychophysically (narrow beam detection). Visual field extent (Goldmann bowl) and temporal and inferotemporal meridian sensitivities (Octopus perimeter) were measured. A wide-angle model was constructed to quantify the impact of the annular opacity on retinal illuminance.

Results

All 10 subjects observed a dark crescent in the far temporal and inferotemporal fields. The opaque annulus reduced effective horizontal pupil diameters from 8 mm to 5.5 mm on-axis and from >2 mm to <1 mm at 90°. Perimetry revealed a 10° reduction in temporal and inferotemporal field extent and increasing loss of sensitivity beyond 70°. The wide-angle model confirmed significant vignetting (>50% beyond 70°), approaching zero retinal illuminance beyond 85°.

Conclusions

Vignetting of rays originating from the far temporal field by axially separated apertures can create symptoms mirroring perceptual reports of negative dysphotopsia in symptomatic pseudophakic patients.

Incidence, Mechanisms, and Predictors of Mean Systolic Gradients ≥20 mm Hg after Transcatheter Aortic Valve Implantation

There is a significant increase in transvalvular gradients after transcatheter aortic valve implantation (TAVI) in some patients; however, mechanisms underlying the greater than expected gradients are unknown. We sought to determine the incidence and mechanisms of greater than expected gradients post-TAVI. A total of 424 patients who underwent TAVI at our institution between November 2008 and August 2015 and had at least 1 follow-up echocardiogram were included in the study. Greater than expected gradients were defined as mean systolic Doppler gradients ≥20 mm Hg. The primary end-point was incidence and mechanisms of mean systolic Doppler gradients ≥20 mm Hg. A total of 36 (8%) patients had mean systolic Doppler gradients ≥20 mm Hg. The mechanisms of mean systolic Doppler gradients ≥20 mm Hg were: patient prosthesis mismatch in 15 (42%) patients, high cardiac output in 13 (36%), prosthetic and periprosthetic regurgitation in 11 (31%), stenosis in 5 (14%), and multiple mechanisms in 8 (22%). Patients with mean systolic Doppler gradients ≥20 mm Hg had higher cardiac re-hospitalization rate, but no difference in mortality or major cardiovascular events when compared with the normal gradient group. Smaller prosthetic valve size (p <0.0001) and larger body mass index (p = 0.02) were associated with mean systolic Doppler gradients ≥20 mm Hg; warfarin therapy at discharge had no effect on gradients. In conclusion, about 8% patients had mean systolic Doppler gradients ≥20 mm Hg following TAVI, and patient-prosthesis mismatch was the most common mechanism. The mean systolic Doppler gradients ≥20 mm Hg after TAVI are not benign and warrant careful surveillance.

Direct anterior approach in lateral position achieves superior cup orientation in total hip arthroplasty: a radiological comparative study of two consecutive series

INTRODUCTION

Although the advantages of total hip arthroplasty (THA) using the direct anterior approach (DAA) have been well documented, DAA in the supine position is limited by the difficulty in exposing the acetabulum and femur, which may result in implant malpositioning and intra-operative complications. Recent studies have reported that DAA-THA in the lateral position can achieve satisfactory clinical and radiographic outcomes. The aim of this study was to investigate the difference in implant alignment between two patient cohorts that underwent primary THA by DAA and the traditional posterolateral approach (PLA) in the lateral position.

METHODS

A total of 208 THAs (110 using DAA and 98 using PLA) were retrospectively analyzed.

RESULTS

The cup anteversion angle was closer to the target anteversion angle, and the accuracy of cup orientation was superior in the DAA group. A total of 82 (74.5%) DAA-THA and 56 (57.1%) PLA-THA cases showed successful inclination and anteversion angles (p = 0.008) of the implant. In addition, 90 (81.8%) DAA-THA and 67 (68.4%) PLA-THA cases had successful anteversion angle (p = 0.024). There was no significant difference between the two groups in terms of successful inclination angle (98 vs. 81, p = 0.181), as well as in the stem alignment in both coronal and sagittal planes.

CONCLUSION

THA using DAA in the lateral position can achieve superior cup orientation compared to PLA while maintaining the stem alignment.