P-Score: A Reference-Image-Based Clinical Grading Scale for Vascular Change in Retinopathy of Prematurity

PURPOSE

The International Classification of Retinopathy of Prematurity Third Edition (ICROP3) acknowledged that plus-like ROP vascular changes occur along a spectrum. Historically, clinician-experts demonstrate variable agreement for plus diagnosis. We developed a 9-photo reference-image set for grading plus-like changes and compared intergrader agreement of the set to standard grading with no-plus/pre-plus/plus.

DESIGN

Retinal photographic grading and expert consensus opinion PARTICIPANTS: Development: 34 international ICROP3 committee members.

VALIDATION

30 ophthalmologists with ROP expertise (15 ICROP3 committee members, 15 non-ICROP3 members) METHODS: Nine ROP fundus images (P1 through P9) representing increasing degrees of zone I vascular tortuosity and dilation, based on ICROP3-committee's 34 members' gradings and consensus image review, were used to establish standard photographs for the "Plus (P) Score." Study participants graded 150 fundus photographs two ways, separated by a 1-week washout period: (1) no-plus/pre-plus/plus disease, (2) choosing the closest P-Score image.

MAIN OUTCOME MEASURES

Intergrader agreement measured by intraclass correlation coefficient (ICC) RESULTS: Intergrader agreement was higher using P-Score (ICC 0.75, 95% CI 0.71-0.79) than no-plus/pre-plus/plus (ICC 0.67, 95% CI 0.62-0.72). Mean P-Scores for images whose mode gradings were no-plus, pre-plus, and plus, were 2.5 (SD 0.7), 4.8 (SD 0.8), and 7.4 (SD 0.8), respectively.

CONCLUSIONS

Intergrader agreement of plus-like vascular change in ROP using the P-Score is high. We recommend incorporation of this 9-image reference set into ICROP3 and clinician daily practice alongside zone/stage/plus. P-score is not yet meant to replace plus diagnosis for treatment decisions, but its use at our institutions has permitted better comparison between examinations for progression and regression, communication between examiners, and documentation of vascular change without fundus imaging. P-score also could provide more detailed ROP classification for clinical trials, consistent with the spectrum of plus-like change that is now formally part of ICROP.

Associations between systemic health and retinal nerve fibre layer thickness in preterm infants at 36 weeks postmenstrual age

BACKGROUND/AIMS

Neonatal insults from systemic diseases have been implicated in the pathway of impaired neurodevelopment in preterm infants. We aimed to investigate the associations between systemic health factors and retinal nerve fibre layer (RNFL) thickness in preterm infants.

METHODS

We prospectively enrolled infants and imaged both eyes at 36±1 weeks postmenstrual age (PMA) using a hand-held optical coherence tomography system at the bedside in the Duke intensive care nurseries. We evaluated associations between RNFL thickness and 29 systemic health factors using univariable and multivariable regression models.

RESULTS

83 infants with RNFL thickness measures were included in this study. Based on the multivariable model, RNFL thickness was positively associated with infant weight at imaging and was negatively associated with sepsis/necrotising enterocolitis (NEC). RNFL thickness was 10.4 µm (95% CI -15.9 to -4.9) lower in infants with than without sepsis/NEC in the univariable analysis (p<0.001). This difference remained statistically significant after adjustment for confounding variables in various combinations (birth weight, birthweight percentile, gestational age, infant weight at imaging and growth velocity). A 250 g increase in infant weight at imaging was associated with a 3.1 µm (95% CI 2.1 to 4.2) increase in RNFL thickness in the univariable analysis (p<0.001).

CONCLUSIONS

Low infant weight and sepsis/NEC were independently associated with thinner RNFL in preterm infants at 36 weeks PMA. To our knowledge, this study is the first to suggest that sepsis/NEC may affect retinal neurodevelopment. Future longitudinal studies are needed to investigate this relationship further.

International Classification of Retinopathy of Prematurity, Third Edition

PURPOSE

The International Classification of Retinopathy of Prematurity is a consensus statement that creates a standard nomenclature for classification of retinopathy of prematurity (ROP). It was initially published in 1984, expanded in 1987, and revisited in 2005. This article presents a third revision, the International Classification of Retinopathy of Prematurity, Third Edition (ICROP3), which is now required because of challenges such as: (1) concerns about subjectivity in critical elements of disease classification; (2) innovations in ophthalmic imaging; (3) novel pharmacologic therapies (e.g., anti-vascular endothelial growth factor agents) with unique regression and reactivation features after treatment compared with ablative therapies; and (4) recognition that patterns of ROP in some regions of the world do not fit neatly into the current classification system.

DESIGN

Review of evidence-based literature, along with expert consensus opinion.

PARTICIPANTS

International ROP expert committee assembled in March 2019 representing 17 countries and comprising 14 pediatric ophthalmologists and 20 retinal specialists, as well as 12 women and 22 men.

METHODS

The committee was initially divided into 3 subcommittees-acute phase, regression or reactivation, and imaging-each of which used iterative videoconferences and an online message board to identify key challenges and approaches. Subsequently, the entire committee used iterative videoconferences, 2 in-person multiday meetings, and an online message board to develop consensus on classification.

MAIN OUTCOME MEASURES

Consensus statement.

RESULTS

The ICROP3 retains current definitions such as zone (location of disease), stage (appearance of disease at the avascular-vascular junction), and circumferential extent of disease. Major updates in the ICROP3 include refined classification metrics (e.g., posterior zone II, notch, subcategorization of stage 5, and recognition that a continuous spectrum of vascular abnormality exists from normal to plus disease). Updates also include the definition of aggressive ROP to replace aggressive-posterior ROP because of increasing recognition that aggressive disease may occur in larger preterm infants and beyond the posterior retina, particularly in regions of the world with limited resources. ROP regression and reactivation are described in detail, with additional description of long-term sequelae.

CONCLUSIONS

These principles may improve the quality and standardization of ROP care worldwide and may provide a foundation to improve research and clinical care.

Natural history of central sparing in geographic atrophy secondary to non-exudative age-related macular degeneration

BACKGROUND

The macular central 1 mm diameter zone is crucial to patients' visual acuity, but the long-term natural history of central sparing in eyes with geographic atrophy (GA) is unknown.

METHODS

We manually segmented GA in 210 eyes with GA involving central 1 mm diameter zone (mean follow-up=3.8 years) in the Age-Related Eye Disease Study. We measured the residual area in central 1 mm diameter zone and calculated central residual effective radius (CRER) as square root of (residual area/π). A linear mixed-effects model was used to model residual size over time. We added a horizontal translation factor to each data set to account for different durations of GA involving the central zone.

RESULTS

The decline rate of central residual area was associated with baseline residual area (p=0.008), but a transformation from central residual area to CRER eliminated this relationship (p=0.51). After the introduction of horizontal translation factors to each data set, CRER declined linearly over approximately 13 years (r²=0.80). The growth rate of total GA effective radius was 0.14 mm/year (95% CI 0.12 to 0.15), 3.7-fold higher than the decline rate of CRER (0.038 mm/year, 95% CI 0.034 to 0.042). The decline rate of CRER was 53.3% higher in eyes with than without advanced age-related macular degeneration in the fellow eyes at any visit (p=0.007).

CONCLUSIONS

CRER in eyes with GA declined linearly over approximately 13 years and may serve as an anatomic endpoint in future clinical trials aiming to preserve the central zone.

Ranibizumab and Bevacizumab for Treatment of Neovascular Age-related Macular Degeneration: Two-Year Results

OBJECTIVE

To describe effects of ranibizumab and bevacizumab when administered monthly or as needed for 2 years and to describe the impact of switching to as-needed treatment after 1 year of monthly treatment.

DESIGN

Multicenter, randomized clinical trial.

PARTICIPANTS

Patients (n = 1107) who were followed up during year 2 among 1185 patients with neovascular age-related macular degeneration who were enrolled in the clinical trial.

INTERVENTIONS

At enrollment, patients were assigned to 4 treatment groups defined by drug (ranibizumab or bevacizumab) and dosing regimen (monthly or as needed). At 1 year, patients initially assigned to monthly treatment were reassigned randomly to monthly or as-needed treatment, without changing the drug assignment.

MAIN OUTCOME MEASURES

Mean change in visual acuity.

RESULTS

Among patients following the same regimen for 2 years, mean gain in visual acuity was similar for both drugs (bevacizumab-ranibizumab difference, -1.4 letters; 95% confidence interval [CI], -3.7 to 0.8; P = 0.21). Mean gain was greater for monthly than for as-needed treatment (difference, -2.4 letters; 95% CI, -4.8 to -0.1; P = 0.046). The proportion without fluid ranged from 13.9% in the bevacizumab-as-needed group to 45.5% in the ranibizumab monthly group (drug, P = 0.0003; regimen, P < 0.0001). Switching from monthly to as-needed treatment resulted in greater mean decrease in vision during year 2 (-2.2 letters; P = 0.03) and a lower proportion without fluid (-19%; P < 0.0001). Rates of death and arteriothrombotic events were similar for both drugs (P > 0.60). The proportion of patients with 1 or more systemic serious adverse events was higher with bevacizumab than ranibizumab (39.9% vs. 31.7%; adjusted risk ratio, 1.30; 95% CI, 1.07-1.57; P = 0.009). Most of the excess events have not been associated previously with systemic therapy targeting vascular endothelial growth factor (VEGF).

CONCLUSIONS

Ranibizumab and bevacizumab had similar effects on visual acuity over a 2-year period. Treatment as needed resulted in less gain in visual acuity, whether instituted at enrollment or after 1 year of monthly treatment. There were no differences between drugs in rates of death or arteriothrombotic events. The interpretation of the persistence of higher rates of serious adverse events with bevacizumab is uncertain because of the lack of specificity to conditions associated with inhibition of VEGF.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Development of a Retinopathy of Prematurity Activity Scale and Clinical Outcome Measures for Use in Clinical Trials

Importance

To facilitate drug and device development for neonates, the International Neonatal Consortium brings together key stakeholders, including pharmaceutical companies, practitioners, regulators, funding agencies, scientists, and families, to address the need for objective, standardized clinical trial outcome measurements to fulfill regulatory requirements. Retinopathy of prematurity (ROP) is a disease that affects preterm neonates. The current International Classification of Retinopathy of Prematurity does not take into account all of the characteristics of ROP and does not adequately discriminate small changes in disease after treatment. These factors are critical for evaluating outcomes in clinical trials.

Observations

There is need for an updated ROP acute disease activity and structure scale as well as end-stage structure and ophthalmologic outcome measures designed for use at different ages. The scale and measures, based on current diagnostic methods and treatments, could be used as a guideline for clinical intervention trials. The scale is intended to be validated against retrospective data and revised for use in future trials. An iterative revision process can be accomplished if new measures are added to clinical trials and evaluated at the end of each trial for prognostic value. The new measures would then be incorporated into a new version of the activity scale and the outcome measures revised.

Conclusions and Relevance

An ROP activity scale and outcome measures to obtain the most robust and discriminatory data for clinical trials are needed. The scales should be dynamic and modified as knowledge and imaging modalities improve and then validated using data from well-documented clinical trials. This approach is relevant to improving clinical trial data quality.

Pain expectations in neuropathic pain: Is it best to be optimistic?

BACKGROUND

Pain expectancy may be an important variable that has been found to influence the effectiveness of treatments for pain. Much of the literature supports a self-fulfilment perspective where expectations for pain relief predict the actual pain experienced. However, in conditions such as neuropathic pain (NeP) where pain relief is difficult to attain, expectations for pain relief could be unrealistic. The objective of this study was to investigate the relationship between realistic/unrealistic expectations and 6-month, post-treatment outcomes.

METHODS

We performed a retrospective analysis of a large cohort of patients with NeP (n = 789) attending tertiary care centres to determine the association between unrealistic (both positive and negative) and realistic expectations with outcomes after multidisciplinary treatment. An expectation variable with three categories was calculated: realistic expectations were those whose expected reduction in pain was similar to the observed mean group reduction in pain, while optimistic and pessimistic expectations were those who over- or under-estimated the expected response to treatment, respectively. The association between baseline realistic/unrealistic expectations and 6-month pain-related disability, catastrophizing and psychological distress was assessed.

RESULTS

Univariable analyses suggested that realistic expectations were associated with lower levels of disability, catastrophizing and psychological distress, compared to unrealistic expectations. However, after adjustment for baseline symptom severity, multivariable analysis revealed that patients with optimistic expectations had lower levels of disability, than those with realistic expectations. Those with pessimistic expectations had higher levels of catastrophizing and psychological distress at follow-up.

CONCLUSIONS

These findings are largely congruent with the self-fulfilment perspective to expectations.

SIGNIFICANCE

This study defined realistic pain expectations with patient data. Examining the relationship between expectations between pain and disability in a large cohort of patients with neuropathic pain.

UAS TOPOGRAPHIC MAPPING WITH VELODYNE LiDAR SENSOR

Unmanned Aerial System (UAS) technology is nowadays willingly used in small area topographic mapping due to low costs and good quality of derived products. Since cameras typically used with UAS have some limitations, e.g. cannot penetrate the vegetation, LiDAR sensors are increasingly getting attention in UAS mapping. Sensor developments reached the point when their costs and size suit the UAS platform, though, LiDAR UAS is still an emerging technology. One issue related to using LiDAR sensors on UAS is the limited performance of the navigation sensors used on UAS platforms. Therefore, various hardware and software solutions are investigated to increase the quality of UAS LiDAR point clouds. This work analyses several aspects of the UAS LiDAR point cloud generation performance based on UAS flights conducted with the Velodyne laser scanner and cameras. The attention was primarily paid to the trajectory reconstruction performance that is essential for accurate point cloud georeferencing. Since the navigation sensors, especially Inertial Measurement Units (IMUs), may not be of sufficient performance, the estimated camera poses could allow to increase the robustness of the estimated trajectory, and subsequently, the accuracy of the point cloud. The accuracy of the final UAS LiDAR point cloud was evaluated on the basis of the generated DSM, including comparison with point clouds obtained from dense image matching. The results showed the need for more investigation on MEMS IMU sensors used for UAS trajectory reconstruction. The accuracy of the UAS LiDAR point cloud, though lower than for point cloud obtained from images, may be still sufficient for certain mapping applications where the optical imagery is not useful.

Equivalency of tricyclic antidepressants in open-label neuropathic pain study

OBJECTIVES

To compare adverse effects, tolerability and efficacy of the tricyclic antidepressants (TCAs) amitriptyline and nortriptyline in management of neuropathic pain due to peripheral neuropathy (PN).

MATERIALS & METHODS

We performed a prospective open-label flexible-dosing comparison of monotherapy or adjuvant therapy using amitriptyline or nortriptyline in PN-associated neuropathic pain. Primary outcomes were quantitative adverse effects and discontinuation rates. Secondary outcomes assessed changes in pain severity, quality of life, disability, sleep efficacy, mood and anxiety, and global improvement. Assessments occurred at 3 and 6 months after initiation. Our hypothesis was that nortriptyline would have better tolerance than amitriptyline.

RESULTS

A total of 228 PN patients were enrolled approximately equally for monotherapy and adjuvant therapy. Adverse effects and discontinuation rates were similar between amitriptyline and nortriptyline interventions. Weight gain was more common with amitriptyline, while nortriptyline use was associated with greater prevalence of dry mouth. Secondary outcome measures were similar in both groups, demonstrating improvement from baseline.

CONCLUSIONS

Amitriptyline and nortriptyline are equivalent for overall adverse effects and discontinuation rates. Either TCA should be equally considered for use in neuropathic pain due to PN. When used as monotherapy or as part of adjuvant therapy, either TCA can be expected to provide approximately 23-26% visual analog scale pain reduction if tolerated. Discontinuations due to inefficacy or adverse effects can be anticipated in 26-37% of patients initiated on either TCA for PN-associated neuropathic pain.

Baseline predictors for one-year visual outcomes with ranibizumab or bevacizumab for neovascular age-related macular degeneration

OBJECTIVE

To determine the baseline predictors of visual acuity (VA) outcomes 1 year after treatment with ranibizumab or bevacizumab for neovascular age-related macular degeneration (AMD).

DESIGN

Cohort study within the Comparison of Age-related Macular Degeneration Treatments Trials (CATT).

PARTICIPANTS

A total of 1105 participants with neovascular AMD, baseline VA 20/25 to 20/320, and VA measured at 1 year.

METHODS

Participants were randomly assigned to ranibizumab or bevacizumab on a monthly or as-needed schedule. Masked readers evaluated fundus morphology and features on optical coherence tomography (OCT). Visual acuity was measured using electronic VA testing. Independent predictors were identified using regression techniques.

MAIN OUTCOME MEASURES

The VA score, VA score change from baseline, and ≥3-line gain at 1 year.

RESULTS

At 1 year, the mean VA score was 68 letters, mean improvement from baseline was 7 letters, and 28% of participants gained ≥3 lines. Older age, larger area of choroidal neovascularization (CNV), and elevation of retinal pigment epithelium (RPE) were associated with worse VA (all P<0.005), less gain in VA (all P<0.02), and a lower proportion gaining ≥3 lines (all P<0.04). Better baseline VA was associated with better VA at 1 year, less gain in VA, and a lower proportion gaining ≥3 lines (all P<0.0001). Predominantly or minimally classic lesions were associated with worse VA than occult lesions (66 vs. 69 letters; P=0.0003). Retinal angiomatous proliferans (RAP) lesions were associated with more gain in VA (10 vs. 7 letters; P=0.03) and a higher proportion gaining ≥3 lines (odds ratio, 1.9; 95% confidence interval, 1.2-3.1). Geographic atrophy (GA) was associated with worse VA (64 vs. 68 letters; P=0.02). Eyes with total foveal thickness in the second quartile (325-425 μm) had the best VA (P=0.01) and were most likely to gain ≥3 lines (P=0.004). Predictors did not vary by treatment group.

CONCLUSIONS

For all treatment groups, older age, better baseline VA, larger CNV area, predominantly or minimally classic lesion, absence of RAP lesion, presence of GA, greater total fovea thickness, and RPE elevation on optical coherence tomography were independently associated with less improvement in VA at 1 year.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Expression of oestrogen receptor β and prognosis of colorectal cancer

BACKGROUND

Previous studies suggest that sex steroids influence colorectal cancer (CRC) carcinogenesis. The oestrogen receptor β (ERβ) is the predominantly expressed ER in the colon and loss of ERβ in CRC has been associated with advanced cancer stages.

METHODS

Information on vital status by the end of 2009 was obtained for 1262 CRC patients recruited between 2003 and 2007. The ERβ expression was immunohistochemically measured and associations of ERβ scores with overall survival (OS), disease-specific survival (DSS) and disease-free survival (DFS) were evaluated using Cox proportional hazard models adjusted for prognostic factors, such as tumour stage and second primary tumours.

RESULTS

Of the 1101 tumour samples with successful measurement, 535 were ERβ negative (48.6%), 381 (34.6%) showed moderate and 185 (16.8%) showed high ERβ expression. Compared with high ERβ expression, lack of ERβ was associated with higher cancer stages as well as greater tumour extent. In multivariate analyses, ERβ negativity was associated with an increased hazard ratio for death (HR=1.61, 95% CI 1.09-2.40, P=0.02), death attributed to CRC (HR=1.54, 95% CI 0.99-2.39, P=0.06) as well as a poorer DFS (DFS HR=1.64, 95% CI 1.23-3.36, P=0.04). The associations were stronger in stage I-III patients (OS HR=2.20, 95% CI 1.28-4.06, P=0.007, DSS HR=2.38, 95% CI 1.20-5.39, P=0.02, respectively).

CONCLUSIONS

Lack of ERβ expression is associated with advanced cancer stages and independently associated with poor survival.

Ranibizumab and bevacizumab for treatment of neovascular age-related macular degeneration: two-year results

OBJECTIVE

To describe effects of ranibizumab and bevacizumab when administered monthly or as needed for 2 years and to describe the impact of switching to as-needed treatment after 1 year of monthly treatment.

DESIGN

Multicenter, randomized clinical trial.

PARTICIPANTS

Patients (n = 1107) who were followed up during year 2 among 1185 patients with neovascular age-related macular degeneration who were enrolled in the clinical trial.

INTERVENTIONS

At enrollment, patients were assigned to 4 treatment groups defined by drug (ranibizumab or bevacizumab) and dosing regimen (monthly or as needed). At 1 year, patients initially assigned to monthly treatment were reassigned randomly to monthly or as-needed treatment, without changing the drug assignment.

MAIN OUTCOME MEASURES

Mean change in visual acuity.

RESULTS

Among patients following the same regimen for 2 years, mean gain in visual acuity was similar for both drugs (bevacizumab-ranibizumab difference, -1.4 letters; 95% confidence interval [CI], -3.7 to 0.8; P = 0.21). Mean gain was greater for monthly than for as-needed treatment (difference, -2.4 letters; 95% CI, -4.8 to -0.1; P = 0.046). The proportion without fluid ranged from 13.9% in the bevacizumab-as-needed group to 45.5% in the ranibizumab monthly group (drug, P = 0.0003; regimen, P < 0.0001). Switching from monthly to as-needed treatment resulted in greater mean decrease in vision during year 2 (-2.2 letters; P = 0.03) and a lower proportion without fluid (-19%; P < 0.0001). Rates of death and arteriothrombotic events were similar for both drugs (P > 0.60). The proportion of patients with 1 or more systemic serious adverse events was higher with bevacizumab than ranibizumab (39.9% vs. 31.7%; adjusted risk ratio, 1.30; 95% CI, 1.07-1.57; P = 0.009). Most of the excess events have not been associated previously with systemic therapy targeting vascular endothelial growth factor (VEGF).

CONCLUSIONS

Ranibizumab and bevacizumab had similar effects on visual acuity over a 2-year period. Treatment as needed resulted in less gain in visual acuity, whether instituted at enrollment or after 1 year of monthly treatment. There were no differences between drugs in rates of death or arteriothrombotic events. The interpretation of the persistence of higher rates of serious adverse events with bevacizumab is uncertain because of the lack of specificity to conditions associated with inhibition of VEGF.

Calibration of a microchannel plate based extreme ultraviolet grazing incident spectrometer at the Advanced Light Source

We present the design and calibration of a microchannel plate based extreme ultraviolet spectrometer. Calibration was performed at the Advance Light Source (ALS) at the Lawrence Berkeley National Laboratory (LBNL). This spectrometer will be used to record the single shot spectrum of radiation emitted by the tapered hybrid undulator (THUNDER) undulator installed at the LOASIS GeV-class laser-plasma-accelerator. The spectrometer uses an aberration-corrected concave grating with 1200 lines/mm covering 11-62 nm and a microchannel plate detector with a CsI coated photocathode for increased quantum efficiency in the extreme ultraviolet. A touch screen interface controls the grating angle, aperture size, and placement of the detector in vacuum, allowing for high-resolution measurements over the entire spectral range.

Adverse effects of corticosteroid therapy in neuromuscular diseased patients are common and receive insufficient prophylaxis

BACKGROUND

Corticosteroid therapy is known to have long-term adverse effects and complications, but our knowledge of the adverse effects of corticosteroids within a neuromuscular patient population is limited.

AIMS OF THE STUDY

We sought to determine the prevalence and impact of corticosteroid use in a population of patients with neuromuscular diseases, as well as possible clinical associations for presence of adverse effects.

METHODS

A retrospective chart review from a comprehensive database from a tertiary care neuromuscular clinic spanning 1988-2007 was performed.

RESULTS

Corticosteroids led to adverse effects in 74% of exposed patients, without proper prophylaxis considered in about 50% of cases. There were no associations determined to have impact upon adverse effect occurrence, including the exposure to cumulative corticosteroid dosing or diagnosis.

CONCLUSION

Corticosteroid therapy is frequently associated with adverse effects, although prediction of their occurrence is not clear. Prophylaxis of their occurrence is underperformed in our tertiary care clinic patient population.

Poor tolerability of high dose ascorbic acid in a population of genetically confirmed adult Charcot-Marie-Tooth 1A patients

BACKGROUND

Preclinical studies have suggested that ascorbic acid (AA) treatment in a mouse model of Charcot-Marie-Tooth type 1A (CMT1A) improves motor function and prolongs lifespan.

AIMS

I sought to determine the safety and tolerability of AA in adult patients with CMT1A.

METHODS

An open-label cohort-controlled 2-year pilot study was used to evaluate the tolerability of 5 g of AA daily. Secondary measurements consisted of clinical and electrophysiological measurements at 0, 12, and 24 months in CMT1A patients.

RESULTS

Twelve CMT1A patients received AA and 10 CMT1A patients formed a cohort group followed in identical manner. Five (42%) patients tolerated this dose of AA for the entire 2-year span, with six patients (50%) developing intolerable gastrointestinal side effects. No significant differences in clinical, disability, or electrophysiological measurements occurred between baseline and final follow-up in patients receiving AA when compared with cohorts.

CONCLUSIONS

High dose AA was not well tolerated in all adult CMT1A patients who may be susceptible to gastrointestinal adverse effects of AA. Studies with greater powers to detect efficacy will be required to test the validity of AA as a therapy in CMT1A patients. Doses lower than 5 g of AA daily may be required for maintenance of tolerability in the CMT1A population.

Neuronal Targeting in Diabetes Mellitus: A Story of Sensory Neurons and Motor Neurons

Diabetes mellitus targets the peripheral nervous system in unique but disabling ways. Although several mechanisms may target peripheral neurons, they render a degenerative pattern of damage that begins in distal terminals. Moreover, sensory neurons are involved early, motor neurons later. By studying a variety of diabetic neuropathy models in rats, mice, and other species, an overall appreciation of its neurodegeneration emerges. Understanding how mechanisms of diabetes complications target peripheral neurons selectively may offer opportunities to intervene before irretrievable neuron loss develops.NEUROSCIENTIST 14(4):311–318, 2008. DOI: 10.1177/1073858408316175

Dramatic MRI improvement with refractory neurosarcoidosis treated with infliximab

BACKGROUND

Neurosarcoidosis is often a devastating, refractory condition without definite pharmacotherapies beyond corticosteroids.

AIM

To describe a case of steroid-refractory neurosarcoidosis with a marked clinical and radiological response to infliximab.

METHODS

We describe the case of a young female patient with biopsy-proven neurosarcoidosis leading to gait failure. She described significant corticosteroid-related side effects without clinical response to the therapy. Infliximab therapy was considered as a possible rescue medication.

RESULTS

Within months of starting intravenous infliximab therapy, she regained her ability to walk and magnetic resonance imaging identified significant improvements over a sustained course of infliximab therapy, including loss of enhancing nodules and loss of meningeal enhancement.

CONCLUSION

Mounting evidence suggests that infliximab is a valuable pharmacological agent in the management of patients with refractory and disabling neurosarcoidosis. Controlled studies of infliximab in this condition are needed.

[Fracture of the intercondylar eminence of the tibia type II in children: 20 surgically-treated cases]

PURPOSE OF THE STUDY

The purpose of this study was to detail therapeutic indications for fractures of the intercondylar eminence of the tibia with little displacement and preservation of the posterior hinge (type II fracture in the Zarincznyj classification).

MATERIAL AND METHODS

We reviewed retrospectively a multicentric serie of type II fractures of the intercondylar eminence observed in children treated surgically. There were twenty patients, ten girls and ten boys, mean age 11.9 years (range 6-16). Imaging included plain x-rays of the knee (anteroposterior and lateral views) in all patients as well as computed tomography (5 patients) and magnetic resonance imaging (1 patient). Surgical treatment was performed in all cases, on average six days after trauma (range 0-25). A medial parapatellar arthrotomy was used in all cases. A non-resorbable thread was used for fixation associated with an anchor in the last four cases. Clinical and radiological assessment was reviewed at mean 3.7 years follow-up.

RESULTS

All children had resumed their sports activities at the same level as before the accident within 4.8 months on average. None of the children suffered from an unstable knee or functional impairment at last follow-up. The Lysholm score was 88.9 on average (range 70-100) at three months postoperative and 99.2 (range 89-100) at last follow-up.

DISCUSSION

There is currently agreement that non-displaced fractures of the anterior intercondylar eminence of the tibia should be treated orthopedically and that forms with displacement require surgery. Conversely, the type II fractures with an anterior gap but a preserved posterior hinge, the appropriate treatment remains a subject of debate. In our experience, surgery would appear to be preferable to orthopedic management. Surgery enables putting correct tension on the anterior crucicate ligament and limits the risk of residual laxity which, even though rarely associated with instability, could in the long-term lead to osteoathritic degradation or meniscal damage.

CONCLUSION

Surgical treatment of fractures of the intercondylar eminence of the tibia with little displacement and preservation of the posterior hinge provides satisfactory results and the best guarantee of long-term stability.

Acetylcholine receptor antibodies in myasthenia gravis are associated with greater risk of diabetes and thyroid disease

OBJECTIVE

Myasthenia gravis (MG) may be associated with the presence of acetylcholine receptor antibodies (AChRAb) [seropositive MG (SPMG)] or their absence [seronegative MG (SNMG)]. Along with features of MG, the presence of the AChRAb may relate to the existence of other immune-mediated diseases. We sought to determine the association of SPMG with other potential autoimmune diseases.

METHODS

A retrospective evaluation of prospectively identified MG patients at a tertiary care center was performed, with patients separated into SPMG and SNMG. Prevalence of other immune-mediated disorders, as well as the epidemiology, sensitivity of diagnostic testing, and thymic pathology, was contrasted between both patient groups.

RESULTS

Of the 109 MG patients identified, 66% were SPMG. SPMG was associated with a greater likelihood of significant repetitive stimulation decrement, the presence of either thymoma or thymic hyperplasia, and the presence of thyroid disease. In addition, all patients with a diagnosis of diabetes, concurrent with MG, were found to be SPMG.

CONCLUSIONS

AChRAb and SPMG impart not only a distinctive clinical and electrophysiological phenotype of MG, but are also associated with the heightened presence of endocrinological disease.

Complement factor H increases risk for atrophic age-related macular degeneration

OBJECTIVE

To determine if the complement factor H gene (CFH) determines risk for development of geographic atrophy (GA).

DESIGN

Retrospective case-control study.

PARTICIPANTS AND CONTROLS

The independent case-control data set contained 647 age-related macular degeneration (AMD) cases (grades 3, 4, or 5) and 163 controls (grades 1 or 2).

METHODS

To determine if CFH had any effect on determining risk for development of GA in an independent case-control data set of 647 AMD cases and 163 controls, the rs1061170 single-nucleotide polymorphism was tested for association, separating grades and analyzing them independently against the controls. Odds ratios were calculated using standard logistic regression models.

MAIN OUTCOME MEASURES

The outcome variable was AMD affection status, and genotypes were coded according to a log-additive model.

RESULTS

There were 407 grade 5, 107 grade 4, 133 grade 3, 35 grade 2, and 128 grade 1 individuals. There was significant association with AMD when comparing grades 3, 4, and 5 versus the controls. The highest odds ratio was obtained when analyzing the grade-4 cases versus the grade-1 controls (OR = 3.217, P<0.0001).

CONCLUSIONS

Our results indicate that CFH increases the risk of developing GA (grade 4) as well as neovascular (grade 5) and milder (grade 3) disease. Although neovascular disease is responsible for the majority of severe vision loss with AMD, GA is also a significant cause of vision loss, and without effective treatment. Therefore, an attempt to clarify its pathogenesis is of the utmost importance.

Remote neurotrophic support of epidermal nerve fibres in experimental diabetes

AIMS/HYPOTHESIS

The support of distal regenerating axons and epidermal nerve fibres through growth factor delivery may depend on the site of delivery. While low-dose systemic insulin provides trophic support for regenerating axons or axons from diabetic animals, its potential action upon the most distal neurites within the epidermis is unknown. In diabetic neuropathy, distal loss of axons is an important clinical and pathological feature. We hypothesised that insulin and IGF-1 delivered intrathecally could support the most distal epidermal nerve fibres.

MATERIALS AND METHODS

As insulin and IGF-1 receptors are present upon sensory ganglion perikarya, we studied the impact of intrathecal delivery of low-dose insulin and equimolar IGF-1 on the density of epidermal axons expressing protein gene product 9.5 in experimental diabetic rats. After 2 months of diabetes induced by streptozotocin injection, intrathecal delivery of low-dose insulin or IGF-1 or saline was provided for 1 month, with comparison to compatible doses of subcutaneous insulin delivery.

RESULTS

Diabetes, in itself, was associated with a decline in epidermal nerve fibre density. Delivery of both intrathecal IGF-1 and insulin was associated with significant improvement in epidermal fibre density (greatest with IGF-1) and length relative to placebo.

CONCLUSIONS/INTERPRETATION

Central intrathecal delivery of IGF-1 and insulin offers remote support for epidermal nerve fibres, subjected to 'dying-back' in early diabetic polyneuropathy.

Rescue and regeneration of injured peripheral nerve axons by intrathecal insulin

Insulin peptide, acting through tyrosine kinase receptor pathways, contributes to nerve development or repair. In this work, we examined the direction, impact and repertoire of insulin signaling in vivo during peripheral nerve regeneration in rats. First, we demonstrated that insulin receptor is expressed on lumbar dorsal root ganglia neuronal perikarya using immunohistochemistry. Immunoblots and polymerase chain reactions confirmed the presence of both alpha and beta insulin receptor subunits in dorsal root ganglia. In vivo and in vitro assessment of dorsal root ganglion neurons showed preferential localization of insulin receptor to perikaryal sites. In vivo, intrathecal delivery of fluorescein isothiocyanate-labeled insulin identified localization around dorsal root ganglia neurons. The direction and impact of potential insulin signaling was evaluated by concurrently delivering insulin or carrier over a 2 week period using mini-osmotic pumps, either intrathecally, near nerve, or with both deliveries, following a selective sural nerve crush injury. Only intrathecal insulin increased the number and maturity of regenerating sensory sural nerve axons distal to the crush site. As well, only intrathecal insulin rescued retrograde loss of sural axons after crush. In a separate experiment, insulin also rescued retrograde loss and atrophy of deep peroneal, largely motor, axons post-injury. Intrathecal insulin increased the expression of calcitonin-gene-related peptide in regenerating sprouts, increased the number of visualized regenerating fiber clusters, and reduced downregulation of calcitonin-gene-related peptide in dorsal root ganglia neurons. Insulin delivered intrathecally does not appear to influence expression of insulin-like growth factor-1 at dorsal root ganglion neurons or near peripheral nerve injury, but was associated with upregulation of insulin receptor alpha subunit in dorsal root ganglia. Intrathecal insulin delivery was associated with greater recovery of thermal sensation and longer distances to stimulus response with the pinch test following sural nerve crush. Insulin signaling at neuron perikarya can drive distal sensory axon regrowth, rescue retrograde alterations of axons and alter axon peptide expression. Moreover, such actions are associated with upregulation of its own receptor.

Histopathologic and ultrastructural features of surgically excised subfoveal choroidal neovascular lesions: submacular surgery trials report no. 7

OBJECTIVES

To identify the histologic and ultrastructural features of surgically excised subfoveal choroidal neovascular lesions from patients enrolled in the Submacular Surgery Trials and to compare them with clinical data.

METHODS

Surgically excised subfoveal choroidal neovascular lesions from patients enrolled in the Submacular Surgery Trials group N trial (lesion predominantly choroidal neovascularization [CNV] with evidence of classic CNV from age-related macular degeneration), group B trial (lesion predominantly hemorrhagic from age-related macular degeneration), and group H trial (idiopathic subfoveal CNV or subfoveal CNV from ocular histoplasmosis syndrome) between October 1, 1999, and September 1, 2001, were submitted to the pathology center. The lesion growth pattern (subretinal pigment epithelial [sub-RPE], subretinal, combined, or indeterminate) and the cellular and extracellular constituents were classified independently. Demographic, clinical, and fluorescein angiographic characteristics of patients, eyes, and lesions, respectively, were compared with the pathologic features.

RESULTS

Of 269 patients assigned to surgery during the 24 months that pathologic specimens were collected, surgical specimens from study eyes of 199 were submitted to the pathology center. Of the 199 routine histologic specimens processed, 144 (72%) were classified as CNV, 51 (26%) as fibrocellular tissue, and 4 (2%) as hemorrhage. The median specimen size was smaller in group H (932 x 208 mum) than in groups N (1980 x 325 mum) and B (1800 x 395 mum). The CNV growth pattern was determined in 91 (46%) of 199 specimens. Of 159 group N and group B lesions, 76 (48%) had an indeterminate growth pattern, 28 (18%) had a sub-RPE growth pattern, and 33 (21%) had sub-RPE and subretinal growth patterns. Of 40 group H lesions, 32 (80%) had an indeterminate growth pattern, 7 (18%) had a subretinal growth pattern, and 1 (2%) had a combined sub-RPE and subretinal pattern. Based on electron microscopy, the most common cellular lesion components were RPE, macrophages, erythrocytes, fibrocytes, and vascular endothelium; the most common extracellular components were 24-nm collagen and fibrin. Basal laminar and linear deposits were found in 80% (40/50) and 16% (8/49) of group N specimens, 66% (43/65) and 5% (3/65) of group B specimens, and 8% (2/26) and 0% (0/26) of group H specimens, respectively.

CONCLUSIONS

Most surgically excised subfoveal specimens had evidence of CNV or tissue associated with CNV. The constituents in CNV were consistent with granulation tissue proliferation. The presence of basal deposits in surgically excised specimens suggested a clinical diagnosis of age-related macular degeneration, even when blood was the predominant component of the lesion. Correlation of growth patterns above or below the RPE with fluorescein angiographic patterns of classic or occult CNV was limited because most specimens had insufficient material to determine these patterns.

Diabetes Mellitus and the Sensory Neuron

Sensory neurons in diabetes may be primarily targeted by diabetes and their involvement may account for prominent sensory loss and pain in diabetic patients. Previous studies demonstrating evidence of excessive polyol flux, microangiopathy, and oxidative stress involving sensory axons and ganglia have been joined by more recent work demonstrating altered neuron phenotype, mitochondrial dysfunction, ion channel alterations, and abnormal growth factor signaling. As such, an interesting and unique panoply of molecular changes in primary sensory neurons has been identified in diabetic models. Insulin deficiency and subsequent changes in second messenger signaling may also play an important role in how sensory neurons respond to diabetes. Applying approaches to support sensory neurons in diabetes may be an important therapeutic direction in diabetic patients.

Student USMLE step 1 preparation and performance

OBJECTIVES

Many medical students take commercial preparation courses to prepare for the USMLE Step 1. This investigation examined the relationships among Step 1 performance, preparation method, and academic achievement in medical school.

METHOD

A survey was conducted on 148 junior students at a medical school in July 2000 regarding their preparation methods for Step 1. Additional data was collected on student Step 1 scores, attendance record on preparation courses, and course grades in medical school.

RESULTS

One hundred students (68%) responded to the survey including 32 preparation course participants. Course participants had significantly lower Step 1 scores and second-year GPAs than those of the non-participants (p < 0.05). However, the effect of preparation method was not significant by using ANCOVA when the second-year GPA was used as a covariate (p = 0.71).

CONCLUSION

Performance on Step 1 is related to academic performance in medical school and not the type of preparation methods.

Student USMLE step 1 preparation and performance

OBJECTIVES

Many medical students take commercial preparation courses to prepare for the USMLE Step 1. This investigation examined the relationships among Step 1 performance, preparation method, and academic achievement in medical school.

METHOD

A survey was conducted on 148 junior students at a medical school in July 2000 regarding their preparation methods for Step 1. Additional data was collected on student Step 1 scores, attendance record on preparation courses, and course grades in medical school.

RESULTS

One hundred students (68%) responded to the survey including 32 preparation course participants. Course participants had significantly lower Step 1 scores and second-year GPAs than those of the non-participants (p < 0.05). However, the effect of preparation method was not significant by using ANCOVA when the second-year GPA was used as a covariate (p = 0.71).

CONCLUSION

Performance on Step 1 is related to academic performance in medical school and not the type of preparation methods.

Hemisensory syndrome is associated with a low diagnostic yield and a nearly uniform benign prognosis

OBJECTIVE

To describe the diagnostic yield and prognosis for patients with hemisensory syndrome.

BACKGROUND

The aetiology, utility of diagnostic procedures, and outcome of hemisensory syndrome in patients with exclusive hemibody complaints having only subjective sensory abnormalities on examination is unknown.

METHODS

Patients were prospectively identified with hemisensory syndrome in a tertiary care institution from 1998-2002. Diagnostic procedures were analysed for sensitivity and clinical follow up was performed.

RESULTS

Thirty four patients, 25 (74%) women, of age 35 (SD 11) years were identified. The hemisensory syndrome occurred on the left side in 23 (68%) cases. Neuroimaging of the brain demonstrated diagnostic abnormalities representing ischaemic aetiology in one case. Other diagnostic testing including cerebrospinal fluid examination, electrophysiological testing, carotid ultrasonography, echocardiography, and blood testing revealed no diagnostic abnormalities. Sixteen patients (47%) continued to complain of hemisensory difficulties after all investigations were completed at 9.6 (5.8) days. One patient with a history of systemic lupus erythematosus and positive antiphospholipid antibodies had a second event diagnosed as stroke seven months after presentation. Clinical follow up at 16 (7) months revealed persisting symptoms in 6 (20%) of 30 patients. Six (50%) of 12 patients agreeing to psychiatric assessment received diagnoses of personality or mood disorders.

CONCLUSIONS

Diagnostic yield in hemisensory syndrome is low, and prognosis is almost always uniformly benign. The author advocates careful assessment of medical history and consideration for neuroimaging in this group of patients.

Electron-yield enhancement in a laser-wakefield accelerator driven by asymmetric laser pulses

The effect of asymmetric laser pulses on electron yield from a laser wakefield accelerator has been experimentally studied using >10(19) cm(-3) plasmas and a 10 TW, >45 fs, Ti:Al2O3 laser. The laser pulse shape was controlled through nonlinear chirp with a grating pair compressor. Pulses (76 fs FWHM) with a steep rise and positive chirp were found to significantly enhance the electron yield compared to pulses with a gentle rise and negative chirp. Theory and simulation show that fast rising pulses can generate larger amplitude wakes that seed the growth of the self-modulation instability, and that frequency chirp is of minimal importance for the experimental parameters.

Supportive and palliative care: experience at the Institut Jules Bordet

The Supportive and Palliative Care Unit of the Institut Jules Bordet officially started its activities in February 1999. Our Unit comprises eight beds (four rooms with one bed each and two rooms with two beds each). We admit advanced cancer patients presenting with severe symptoms whose control is going to require all the expertise of a multidisciplinary team. Whilst these eight beds are identified geographically in the hospital, the team's mobility assures continuity of care for patients who wish to stay in another department. The infrastructure of the Unit and its rooms allow close family members who wish to sleep close to the patients to do so. Otherwise, visits are allowed round the clock, though always with due consideration for patients' comfort. Patients are referred either by a physician working in our Institution (medical oncologist, surgeon, or radiotherapist) or by their family physicians. Less frequently, patients themselves specifically ask to be admitted to our Unit. The activity of the Unit itself during its first year of functioning can be summarized as follows. We admitted 155 advanced cancer patients, for a total number of 210 hospitalizations. Patients were admitted a median of 35 months after their diagnosis and a median of 20 days before death. Stays were generally short (median 11 days). We systematically used quantitative assessment tools (MMSQ, MDAS,EFAT and various VAS) to detect and monitor their symptoms and any complications. The main symptoms on admission were pain, anorexia, asthenia, dyspnea and anxiety/depression. Pain, nausea/vomiting, constipation and cough were controlled in almost all patients, whereas control of asthenia and anorexia was most often insufficient. In 51% of our cases the patients could be discharged home; 40% died in the unit; 4% were transferred to long-term palliative care units and 1% to other units within our Institution (4% were still hospitalized at the time of this analysis).