Navigating the Healthcare Conundrum: Leadership Perspective from a Premier Healthcare Organization in Loma Linda's Blue Zone.

Navigating the healthcare conundrum in the Blue Zone of Loma Linda, California, requires understanding the unique factors that make this region stand out in terms of health and longevity. But more important is understanding the healthcare system sustaining the Blue Zone in Loma Linda, California. In an era marked by soaring healthcare costs and diminishing reimbursement rates, hospitals and physicians face an unprecedented challenge: providing excellent patient care while maintaining financial sustainability. This leadership perspective publication paper delves into the multifaceted struggles encountered by healthcare and hospital leaders, exploring the root causes, implications, and potential solutions for this complex issue. As we examine the evolving healthcare landscape, we aim to shed light on the critical need for innovative approaches to sustain the future of healthcare excellence in one of the five original Blue Zones.

Effectiveness, safety and treatment adherence of biosimilar follow-on insulin in diabetes management.

AIM: To assess the change in HbA1c after initiation of biosimilar follow-on insulin (Basaglar) or reference insulin (Lantus) among patients with type 2 diabetes. We also compared treatment adherence, safety events and costs at 1 year after initiation of insulin. MATERIALS AND METHODS: Using claims data from a large US health plan during 2016-2020, we identified adults with type 2 diabetes who initiated either Basaglar or Lantus. Generalized linear regression modelling assessed the differences in outcomes between the two groups. A 0.4% margin was used to determine non-inferiority for HbA1c. RESULTS: The study included 1136 Basaglar users and 6304 Lantus users. Both Lantus and Basaglar groups showed more than 1% reduction in HbA1c over 6 months and over 12 months. Reduction in HbA1c with Basaglar was similar (non-inferior) to that with Lantus, with an adjusted difference of Basaglar to Lantus of 0.14% (95% CI -0.02 to 0.30) over 6 months and 0.17% (95% CI 0.02 to 0.32) over 12 months. Rates of adverse events were similar for both hypoglycaemia and vascular events. The Basaglar group showed higher adherence in terms of proportion of days covered (adjusted difference 0.06, 95% CI 0.04 to 0.08). Medical costs were similar, but the cost of Basaglar was lower (adjusted mean cost difference -$462, 95% CI -$556 to -$363) after adjustment. CONCLUSIONS: In patients with type 2 diabetes, Basaglar provided similar glycaemic control compared with Lantus, had a similar safety profile and lower drug costs, and showed more favourable adherence.

The Long-Term Residual Effects of Low-Magnitude Mechanical Stimulation on Murine Femoral Mechanics.

As an alternative to drug treatments, low-magnitude mechanical stimulation (LMMS) may improve skeletal health without potential side effects from drugs. LMMS has been shown to increase bone health short term in both animal and clinical studies. Long-term changes to the mechanical properties of bone from LMMS are currently unknown, so the objective of this research was to establish the methodology and preliminary results for investigating the long-term effects of whole body vibration therapy on the elastic and viscoelastic properties of bone. In this study, 10-week-old female BALB/cByJ mice were given LMMS (15 min/day, 5 days/week, 0.3 g, 90 Hz) for 8 weeks; SHAM did not receive LMMS. Two sets of groups remained on study for an additional 8 or 16 weeks post-LMMS (N = 17). Micro-CT and fluorochrome histomorphology of these femurs were studied and results were published by Bodnyk et al. (2020, "The Long-Term Residual Effects of Low-Magnitude Mechanical Stimulation Therapy on Skeletal Health," J. Biol. Eng., 14, Article No. 9.). Femoral quasi-static bending stiffness trended 4.2% increase in stiffness after 8 weeks of LMMS and 1.3% increase 8 weeks post-LMMS compared to SHAM. Damping, tan delta, and loss stiffness significantly increased by 17.6%, 16.3%, and 16.6%, respectively, at 8 weeks LMMS compared to SHAM. Finite element models of applied LMMS signal showed decreased stress in the mid-diaphyseal region at both 8-week LMMS and 8-week post-LMMS compared to SHAM. Residual mechanical changes in bone during and post-LMMS indicate that LMMS could be used to increase long-term mechanical integrity of bone.

Thyroid eye disease in New Zealand: interaction between ethnicity and smoking status.

AIM: This study was conducted to describe the epidemiology of thyroid eye disease (TED) in New Zealand. METHODS: One hundred and sixty-one subjects with TED seen over a 14-year period in Auckland, from a combined ophthalmology-endocrinology clinic, had data extracted from clinical notes. RESULTS: Median age at onset was 47.0±15.1 years and 77.6% were female. Crude yearly incidence of TED (per 1,000,000) was 12.6 in non-smokers and 67.3 in smokers (p<0.001).  On univariate analysis, female gender, Maori ethnicity and smoking were associated with incidence of TED. On multivariate analysis, female gender and smoking status were associated with risk of TED, and the difference in ethnicity was explained by smoking status. Maori subjects with TED were more likely to be current smokers (72.7%) compared to European (39.2%), Pacific Peoples (33.3%), Asian (8.3%) and Other (12.5%). Maori ethnicity and current smokers were associated with a higher clinical activity score at presentation (p=0.049 and p=0.027). CONCLUSION: A strong association was demonstrated with female gender and smoking status and rate of TED. Maori have increased rates of TED; however, this difference was explained by smoking. Eliminating smoking would result in at least a 28.1% reduction in TED incidence in New Zealand.

The long-term residual effects of low-magnitude mechanical stimulation therapy on skeletal health.

BACKGROUND: Low-magnitude mechanical stimulation (LMMS) may improve skeletal health. The objective of this research was to investigate the long-term residual effects of LMMS on bone health. 10-week old female mice were given LMMS for 8 weeks; SHAM did not receive LMMS. Some groups remained on study for an additional 8 or 16 weeks post treatment (N = 17). RESULTS: Epiphyseal trabecular mineralizing surface to bone surface ratio (MS/BS) and bone formation rate (BFR/BS) were significantly greater in the LMMS group compared to the SHAM group at 8 weeks by 92 and 128% respectively. Mineral apposition rate (MAR) was significantly greater in the LMMS group 16 weeks post treatment by 14%.Metaphyseal trabecular bone mineral density (BMD) increased by 18%, bone volume tissue volume ratio (BV/TV) increased by 37%, and trabecular thickness (Tb.Th.) increased by 10% with LMMS at 8 weeks post treatment. Significant effects 16 weeks post treatment were maintained for BV/TV and Tb.Th. The middle-cortical region bone volume (BV) increased by 4% and cortical thickness increased by 3% with 8-week LMMS. CONCLUSIONS: LMMS improves bone morphological parameters immediately after and in some cases long-term post LMMS. Results from this work will be helpful in developing treatment strategies to increase bone health in younger individuals.

Improvement in Glycemic and Lipid Profiles in Type 2 Diabetics with a 90-Day Ketogenic Diet.

Because low-carbohydrate diets are effective strategies to improve insulin resistance, the hallmark of type 2 diabetes, the purpose of reporting these clinical cases was to reveal the meaningful changes observed in 90 days of low-carbohydrate (LC) ketogenic dietary intervention in female type 2 diabetics aged 18-45. Eleven women (BMI 36.3 kg/m2) who were recently diagnosed with type 2 diabetes based on HbA1c over 6.5% (8.9%) volunteered to participate in an intensive dietary intervention to limit dietary carbohydrates to under 30 grams daily for 90 days. The main outcome was to determine the degree of change in HbA1c, while secondary outcomes included body weight, blood pressure, and blood lipids. The volunteers lost significant weight (85.7 ± 3.2 kg to 76.7 ± 2.8 kg) and lowered systolic (134.0 ± 1.6 to 123.3 ± 1.1 mmHg) and diastolic (89.9 ± 1.3 to 82.6 ± 1.0 mmHg) blood pressure. HbA1c dropped to 5.6%. Most blood lipids were significantly altered, including HDL cholesterol (43.1 ± 4.4 to 52.3 ± 3.3 mg/dl), triglycerides (177.0 ± 19.8 to 92.1 ± 8.7 mg/dl), and the TG : HDL ratio (4.7 ± 0.8 to 1.9 ± 0.2). LDL cholesterol was not significantly different. AST and ALT, plasma markers of liver health, were reported for eight patients and revealed no significant changes. These findings indicate that a short-term intervention emphasizing protein and fat at the expense of dietary carbohydrate functionally reversed the diabetes diagnosis, as defined by HbA1c. Furthermore, the intervention lowered body weight and blood pressure, while eliciting favorable changes in blood lipids.

Corneoscleral stiffening increases IOP spike magnitudes during rapid microvolumetric change in the eye.

Factors governing the steady-state IOP have been extensively studied; however, the dynamic aspects of IOP are less understood. Clinical studies have suggested that intraocular pressure (IOP) fluctuation may be associated with glaucoma risk. This study aims to investigate how stiffening of corneoscleral biomechanical properties affects IOP spikes induced by rapid microvolumetric change. Porcine eyes (n = 25 in total) were subjected to volumetric infusions before and after external treatment of a circular area (11 mm diameter) in either the central cornea or posterior sclera. The treated area in the control group was immersed in phosphate-buffered saline (PBS) for 40 min, while the treated area of the chemical crosslinking group was immersed in 4% glutaraldehyde/PBS for 40 min. A subset of the sham-treated eyes was also subjected to volumetric infusions at a raised steady-state IOP. The magnitude of IOP spikes increased after localized chemical crosslinking of either the cornea (27.5% increase, p < 0.001) or the sclera (14.3% increase, p < 0.001) with corneal crosslinking having a stronger effect than scleral crosslinking (p = 0.018). We also observed that raising the steady-state IOP from 15 to 25 mmHg resulted in marked increase in IOP spike magnitudes by 63.9% (p < 0.001). These results suggested that an increased corneoscleral stiffness could significantly increase IOP spike magnitudes at the same volumetric change. Corneal stiffness appeared to have a strong impact on the IOP spike magnitude and may play a major role in regulating rapid volume-pressure dynamics. An increase in steady-state IOP also resulted in larger IOP fluctuations due to the increased "apparent" stiffness of the ocular shell, suggesting a potential interaction between the magnitude of IOP and its fluctuations. Corneoscleral properties may represent additional pathways for understanding and managing glaucoma risk and warrant future investigation.

Partnering to develop a continuing professional development program in a low-resource setting: Cambodia.

OBJECTIVE: To design and implement a continuing professional development (CPD) program for Cambodian ophthalmologists. DESIGN: Partnering (twinning) between the Royal Australian and New Zealand College of Ophthalmologists (RANZCO) and the Cambodian Ophthalmological Society (COS). PARTICIPANTS: Practicing ophthalmologists in Cambodia. METHODS: A conjoint committee comprising 4 ophthalmologists from RANZCO and 3 ophthalmologists from COS was established, supported by a RANZCO administrative team experienced in CPD administration. CPD requirements and recording were adapted from the RANZCO CPD framework. Cambodian ophthalmologists were surveyed during program implementation and after handover to COS. RESULTS: At the end of the 3-year program at handover to COS, a CPD program and online recording system was established. All 47 (100%) practicing ophthalmologists in Cambodia were registered for CPD, and 21/47 (45%) were actively participating in the COS CPD program online recording. Surveys of attitudes toward CPD demonstrated no significant change. CONCLUSIONS: Partnering was moderately effective in establishing a CPD program for Cambodian ophthalmologists. Uptake of CPD may have been limited by lack of a requirement for CPD for continuing medical licensure in Cambodia. Follow-up will be necessary to demonstrate CPD program longevity.

In vivo ocular biomechanical compliance in thyroid eye disease.

BACKGROUND/AIMS: To compare the ocular biomechanical properties in patients with thyroid eye disease (TED) and healthy participants using a non-contact Scheimpflug-based tonometer (CorVis ST). METHODS: All eyes were examined by slit lamp biomicroscopy, corneal tomography and the CorVis ST (CST). Patients with TED were examined by a fellowship trained oculoplastics specialist to determine status and assess severity. The outputs from CST and additionally derived parameters, including maximum orbital deformation (MOD), were compared between healthy participants and patients with TED using Student's t-test. Furthermore, a multiple linear regression analysis was used to control for various factors known to influence ocular biomechanical responses to an air pulse. RESULTS: This study included 20 patients with TED and compared them with a cohort of 152 healthy participants. The mean age of patients with TED was 46.7±19.0 years and the mean age of healthy participants was 35.9±13.8 years (p=0.03). There were no statistically significant differences in gender distributions between both groups (p>0.05). Several CST parameters were significantly different between groups (p<0.05). Of note, however, MOD was significantly lower in patients with TED (0.16±0.04 mm) compared with the healthy participants (0.25±0.05 mm, p<0.001). This dissimilarity remained even after controlling for the various cofactors. Receiver-operating characteristic analysis revealed an area under the curve of 0.91±0.04 (95% CI 0.84 to 0.98, p<0.001) for MOD. CONCLUSIONS: The in vivo ocular biomechanics as measured by the CST reflects a reduced orbital compliance. This method of ocular biomechanical assessment may aid in the categorisation of TED severity and assist in monitoring and/or diagnosing TED.

Mapping 3D Strains with Ultrasound Speckle Tracking: Method Validation and Initial Results in Porcine Scleral Inflation.

This study aimed to develop and validate a high frequency ultrasound method for measuring distributive, 3D strains in the sclera during elevations of intraocular pressure. A 3D cross-correlation based speckle-tracking algorithm was implemented to compute the 3D displacement vector and strain tensor at each tracking point. Simulated ultrasound radiofrequency data from a sclera-like structure at undeformed and deformed states with known strains were used to evaluate the accuracy and signal-to-noise ratio (SNR) of strain estimation. An experimental high frequency ultrasound (55 MHz) system was built to acquire 3D scans of porcine eyes inflated from 15 to 17 and then 19 mmHg. Simulations confirmed good strain estimation accuracy and SNR (e.g., the axial strains had less than 4.5% error with SNRs greater than 16.5 for strains from 0.005 to 0.05). Experimental data in porcine eyes showed increasing tensile, compressive, and shear strains in the posterior sclera during inflation, with a volume ratio close to one suggesting near-incompressibility. This study established the feasibility of using high frequency ultrasound speckle tracking for measuring 3D tissue strains and its potential to characterize physiological deformations in the posterior eye.

Three-Dimensional Strains in Human Posterior Sclera Using Ultrasound Speckle Tracking.

Intraocular pressure (IOP) induced strains in the peripapillary sclera may play a role in glaucoma progression. Using inflation testing and ultrasound speckle tracking, the 3D strains in the peripapillary sclera were measured in nine human donor globes. Our results showed that the peripapillary sclera experienced through-thickness compression and meridional stretch during inflation, while minimal circumferential dilation was observed when IOP was increased from 10 to 19 mmHg. The maximum shear was primarily oriented in the through-thickness, meridional cross sections and had a magnitude slightly larger than the first principal strain. The tissue volume had minimal overall change, confirming near-incompressibility of the sclera. Substantial strain heterogeneity was present in the peripapillary region, with local high strain areas likely corresponding to structural heterogeneity caused by traversing blood vessels. These 3D strain characteristics provide new insights into the biomechanical responses of the peripapillary sclera during physiological increases of IOP. Future studies are needed to confirm these findings and investigate the role of these biomechanical characteristics in ocular diseases.

Intraoperative ultrasonography and surgical strategy in hepatic resection: What difference does it make?

BACKGROUND: With modern advancements in preoperative imaging for liver surgery, intraoperative ultrasonography (IOUS) may be perceived as superfluous. Our aim was to determine if IOUS provides new information that changes surgical strategy in hepatic resection. METHODS: We retrospectively analyzed 121 consecutive liver resections performed at a single institution. Preoperative computed tomography and/or magnetic resonance imaging determined the initial surgical strategy. The size, location and number of lesions were compared between IOUS and preoperative imaging. Reviewing the operative report helped determine if new IOUS findings led to changes in surgical strategy. Pathology reports were analyzed for margins. RESULTS: Of 121 procedures analyzed, IOUS was used in 88. It changed the surgical plan in 15 (17%) cases. Additional tumours were detected in 10 (11%) patients. A change in tumour size and location were detected in 2 (2%) and 3 (4%) patients, respectively. Surgical plans were altered in 7 (8%) cases for reasons not related to IOUS. There was no significant difference (p = 0.74) in average margin length between the IOUS and non-IOUS groups (1.09 ± 1.18 cm v. 1.18 ± 1.05 cm). CONCLUSION: Surgical strategy was altered owing to IOUS results in a substantial number of cases, and IOUS-guided resection planes resulted in R0 resections in nearly all procedures. The best operative plan in hepatic resection includes IOUS.

CONTEXTE: Compte tenu des récentes avancées de l'imagerie préopératoire pour les chirurgies du foie, l'utilisation de l'échographie peropératoire pourrait paraître inutile. Notre objectif était de déterminer si cette pratique permet d'obtenir des images nouvelles motivant un changement de stratégie chirurgicale pendant une résection hépatique. MÉTHODES: Nous avons analysé rétrospectivement 121 résections hépatiques consécutives réalisées dans un même établissement. La tomographie par ordinateur ou l'imagerie par résonance magnétique préopératoires ont été utilisées pour choisir la stratégie chirurgicale initiale. La taille et la position des tumeurs détectées ainsi que leur nombre ont été comparés selon la méthode utilisée : échographie peropératoire ou imagerie préopératoire. Nous avons étudié les rapports opératoires pour déterminer si l'échographie peropératoire avait entraîné un changement de stratégie chirurgicale et avons examiné les rapports de pathologie pour connaître les résultats de l'analyse des contours. RÉSULTATS: L'échographie peropératoire a été utilisée dans 88 des 121 interventions étudiées. Elle a influé sur la stratégie chirurgicale dans 15 cas (17 %). De nouvelles tumeurs ont été détectées chez 10 patients (11 %), et un changement dans la taille ou la position de la tumeur a été détecté chez 2 (2 %) et 3 patients (4 %), respectivement. Dans 7 cas (8 %), la stratégie chirurgicale a été modifiée, mais pour des raisons indépendantes des résultats de l'échographie. Nous n'avons pas observé de différence significative (p = 0,74) entre la taille moyenne des contours pour les 2 groupes de patients, soit ceux qui ont été soumis à l'échographie peropératoire et ceux qui ne l'ont pas été (1,09 ± 1,18 cm par rapport à 1,18 ± 1,05 cm). CONCLUSION: La stratégie chirurgicale a été modifiée en fonction des résultats de l'échographie peropératoire dans un nombre important de cas, et dans presque tous les cas, l'échographie peropératoire a donné lieu à une résection complète. La meilleure approche lors d'une résection hépatique inclut donc l'échographie peropératoire.

Regional variation of bone tissue properties at the human mandibular condyle.

The temporomandibular joint (TMJ) bears different types of static and dynamic loading during occlusion and mastication. As such, characteristics of mandibular condylar bone tissue play an important role in determining the mechanical stability of the TMJ under the macro-level loading. Thus, the objective of this study was to examine regional variation of the elastic, plastic, and viscoelastic mechanical properties of human mandibular condylar bone tissue using nanoindentation. Cortical and trabecular bone were dissected from mandibular condyles of human cadavers (9 males, 54-96 years). These specimens were scanned using microcomputed tomography to obtain bone tissue mineral distribution. Then, nanoindentation was conducted on the surface of the same specimens in hydration. Plastic hardness (H) at a peak load, viscoelastic creep (Creep/Pmax), viscosity (η), and tangent delta (tan δ) during a 30 second hold period, and elastic modulus (E) during unloading were obtained by a cycle of indentation at the same site of bone tissue. The tissue mineral and nanoindentation parameters were analyzed for the periosteal and endosteal cortex, and trabecular bone regions of the mandibular condyle. The more mineralized periosteal cortex had higher mean values of elastic modulus, plastic hardness, and viscosity but lower viscoelastic creep and tan δ than the less mineralized trabecular bone of the mandibular condyle. These characteristics of bone tissue suggest that the periosteal cortex tissue may have more effective properties to resist elastic, plastic, and viscoelastic deformation under static loading, and the trabecular bone tissue to absorb and dissipate time-dependent viscoelastic loading energy at the TMJ during static occlusion and dynamic mastication.

Effect of PET before liver resection on surgical management for colorectal adenocarcinoma metastases: a randomized clinical trial.

IMPORTANCE: Patients with colorectal cancer with liver metastases undergo hepatic resection with curative intent. Positron emission tomography combined with computed tomography (PET-CT) could help avoid noncurative surgery by identifying patients with occult metastases. OBJECTIVES: To determine the effect of preoperative PET-CT vs no PET-CT (control) on the surgical management of patients with resectable metastases and to investigate the effect of PET-CT on survival and the association between the standardized uptake value (ratio of tissue radioactivity to injected radioactivity adjusted by weight) and survival. DESIGN, SETTING, AND PARTICIPANTS: A randomized trial of patients older than 18 years with colorectal cancer treated by surgery, with resectable metastases based on CT scans of the chest, abdomen, and pelvis within the previous 30 days, and with a clear colonoscopy within the previous 18 months was conducted between 2005 and 2013, involving 21 surgeons at 9 hospitals in Ontario, Canada, with PET-CT scanners at 5 academic institutions. INTERVENTIONS: Patients were randomized using a 2 to 1 ratio to PET-CT or control. MAIN OUTCOMES AND MEASURES: The primary outcome was a change in surgical management defined as canceled hepatic surgery, more extensive hepatic surgery, or additional organ surgery based on the PET-CT. Survival was a secondary outcome. RESULTS: Of the 263 patients who underwent PET-CT, 21 had a change in surgical management (8.0%; 95% CI, 5.0%-11.9%). Specifically, 7 patients (2.7%) did not undergo laparotomy, 4 (1.5%) had more extensive hepatic surgery, 9 (3.4%) had additional organ surgery (8 of whom had hepatic resection), and the abdominal cavity was opened in 1 patient but hepatic surgery was not performed and the cavity was closed. Liver resection was performed in 91% of patients in the PET-CT group and 92% of the control group. After a median follow-up of 36 months, the estimated mortality rate was 11.13 (95% CI, 8.95-13.68) events/1000 person-months for the PET-CT group and 12.71 (95% CI, 9.40-16.80) events/1000 person-months for the control group. Survival did not differ between the 2 groups (hazard ratio, 0.86 [95% CI, 0.60-1.21]; P = .38). The standardized uptake value was associated with survival (hazard ratio, 1.11 [90% CI, 1.07-1.15] per unit increase; P < .001). The C statistic for the model including the standardized uptake value was 0.62 (95% CI, 0.56-0.68) and without it was 0.50 (95% CI, 0.44-0.56). The difference in C statistics is 0.12 (95% CI, 0.04-0.21). The low C statistic suggests that the standard uptake value is not a strong predictor of overall survival. CONCLUSIONS AND RELEVANCE: Among patients with potentially resectable hepatic metastases of colorectal adenocarcinoma, the use of PET-CT compared with CT alone did not result in frequent change in surgical management. These findings raise questions about the value of PET-CT scans in this setting. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00265356.

Biaxial mechanical testing of posterior sclera using high-resolution ultrasound speckle tracking for strain measurements.

This study aimed to characterize the mechanical responses of the sclera, the white outer coat of the eye, under equal-biaxial loading with unrestricted shear. An ultrasound speckle tracking technique was used to measure tissue deformation through sample thickness, expanding the capabilities of surface strain techniques. Eight porcine scleral samples were tested within 72 h postmortem. High resolution ultrasound scans of scleral cross-sections along the two loading axes were acquired at 25 consecutive biaxial load levels. An additional repeat of the biaxial loading cycle was performed to measure a third normal strain emulating a strain gage rosette for calculating the in-plane shear. The repeatability of the strain measurements during identical biaxial ramps was evaluated. A correlation-based ultrasound speckle tracking algorithm was used to compute the displacement field and determine the distributive strains in the sample cross-sections. A Fung type constitutive model including a shear term was used to determine the material constants of each individual specimen by fitting the model parameters to the experimental stress-strain data. A non-linear stress-strain response was observed in all samples. The meridian direction had significantly larger strains than that of the circumferential direction during equal-biaxial loadings (P's<0.05). The stiffness along the two directions was also significantly different (P=0.02) but highly correlated (R(2)=0.8). These results showed that the mechanical properties of the porcine sclera were nonlinear and anisotropic under biaxial loading. This work has also demonstrated the feasibility of using ultrasound speckle tracking for strain measurements during mechanical testing.

Correlation between biomechanical responses of posterior sclera and IOP elevations during micro intraocular volume change.

PURPOSE: This study tested the hypothesis that intraocular pressure (IOP) elevations, induced by controlled increase of intraocular volume, are correlated with the biomechanical responses of the posterior sclera. METHODS: Porcine globes were tested within 48 hours postmortem. The first group of globes (n = 11) was infused with 15 µL of phosphate-buffered saline at three different rates to investigate rate-dependent IOP elevations. The second group (n = 16) was first infused at the fast rate and then underwent inflation tests to investigate the relationship between IOP elevations (ΔIOP) and scleral strains. The strains in the superotemporal region of the posterior sclera were measured by ultrasound speckle tracking. Linear regression was used to examine the association between ΔIOP due to micro-volumetric infusion and the scleral strains at a specific inflation pressure. RESULTS: The average ΔIOP was 14.9 ± 4.3 mm Hg for the infusion of 15 µL in 1 second. The ΔIOP was greater for the faster infusion rates but highly correlated across different rates (P < 0.001). A significant negative association was found between the ΔIOP and the tangential strains in both the circumferential (R(2) = 0.54, P = 0.003) and meridian (R(2) = 0.53, P = 0.002) directions in the posterior sclera. CONCLUSIONS: This study showed a substantial increase in IOP, with a large intersubject variance during micro-volumetric change. A stiffer response of the sclera was associated with larger IOP spikes, providing experimental evidence linking corneoscleral biomechanics to IOP fluctuation. In vivo measurement of corneoscleral biomechanics may help better predict the dynamic profile of IOP.

Use of x-ray film implant for the repair of orbital fractures.

PURPOSE: To evaluate the experience with sterilized x-ray film in the repair of orbital blow-out fractures (BOFs). METHODS: A retrospective review of case notes from 56 patients with orbital BOF repaired using sterilized x-ray film onlay implants at 2 institutions between November 2004 and December 2010. Patient demographics, timing of surgery, surgical approach, postoperative complications, and length of follow up were recorded. RESULTS: Fifty-six patients (44 men, 12 women) received sterilized x-ray film implants during the 6-year study period. Mean age at the time of repair was 29 years (range 4-85 years). For 68% of patients, surgical repair was performed within 2 weeks of injury. Average length of postoperative follow up was 5.5 months (range 1-36 months), 48% had follow up >3 months. Following surgical repair, diplopia in primary or down gaze reduced from 98% to 4% and enophthalmos ≥2 mm reduced from 21% to 5% cases. One patient required a second operation for repositioning of an incompletely reduced fracture. A second patient presented 9 months postoperatively with recurrent episodes of proptosis, and the implant and its surrounding pseudocapsule were subsequently removed. There were no cases of visual loss, implant infection, or migration. CONCLUSIONS: This series has demonstrated that in selected orbital fractures sterilized x-ray film can provide a safe, effective, and low-cost onlay implant.