Is the walk ratio a window to the cerebellum in multiple sclerosis? A structural magnetic resonance imaging study

BACKGROUND AND PURPOSE

Existing research studies have demonstrated a relationship between magnetic resonance imaging (MRI) neuroimaging measures and walking speed in people with multiple sclerosis (PwMS). However, to date there are no data as to the brain structures involved in gait coordination and control in PwMS. Therefore, the aim of our study was to investigate the association between walk ratio, an indicator of gait coordination, and related brain structures in PwMS.

METHODS

A brain MRI was performed by a 3.0-T MR scanner in conjunction with a volumetric analysis based on three-dimensional T1-weighted images. Regions of interest were volumes of the hippocampus, amygdala, putamen, caudate, pallidum, thalamus, cerebellum and the corpus callosum regions. Walking speed and walk ratio, defined as step length divided by step rate, was measured whilst walking on an electronic walkway.

RESULTS

In all, 343 PwMS (41.1 ± 13.4 years, 69.1% female, median Expanded Disability Status Scale 2.5) were included in the study. A significant association was found between the left cerebellum volume and walk ratio after controlling for age, gender, total cranial volume and disability; R²  = 0.379, P = 0.002. A similar association was found between the right cerebellum volume and walk ratio, R²  = 0.364, P = 0.002. No correlations were observed between walk ratio and the thalamus, basal ganglia, hippocampus, amygdala and the corpus callosum volumes. No association was found between walking speed and all brain measures.

CONCLUSIONS

The walk ratio should be considered when evaluating and assessing PwMS presenting with ataxia. Furthermore, it is also hypothesized that a low walk ratio indicates a lower cerebellum volume in the MS population.

Traumatic Cataracts in Children, Long-Term Follow-up in an Israeli Population: A Retrospective Study

BACKGROUND

Ocular trauma in the pediatric population may lead to cataract formation. Managing traumatic cataracts in a visually immature child is a major challenge and can result in poor visual outcome.

OBJECTIVES

To review our long-term surgical experience with childhood unilateral traumatic cataracts.

METHODS

A retrospective observational study of children with unilateral traumatic cataracts with minimal follow-up of 5 years was conducted. Main outcomes included final visual acuity (VA) and occurrence of complications.

RESULTS

Of the 18 children included in the study, 83% were male. Mean follow-up time was 12.5 years. Median age at injury was 7.5 years. Eleven patients (61%) presented with penetrating trauma injuries and 7 (39%) with blunt trauma. Sixteen patients (89%) had cataracts at presentation, while in two the cataracts developed during follow-up. Of the 18 total, cataract removal surgery was conducted in 16 (89%) with intraocular lens (IOL) implantation in 14 (87.5%), while 2 remained aphakic (12.5%). Two (11%) were treated conservatively. Long-term complications included IOL dislocation in 5 (36%), glaucoma in 8 (44%), and posterior capsular opacity in 10 (71%). No correlation was found between final visual acuity and the time interval between injury and IOL implantation nor between final VA and age at trauma. However, the final VA did correlate with time of follow-up.

CONCLUSIONS

Severe complications occurred in over 30% of the patients during a long follow-up (mean 12.5 years). This finding shows the importance of discussions between the operating physician and the parents regarding the prognosis and necessity of scheduled follow-up.

Development of "Predict ME," an online classifier to aid in differentiating diabetic macular edema from pseudophakic macular edema

PURPOSE

Differentiating the underlying pathology of macular edema in patients with diabetic retinopathy following cataract surgery can be challenging. In 2015, Munk and colleagues trained and tested a machine learning classifier which uses optical coherence tomography variables in order to distinguish the underlying pathology of macular edema between diabetic macular edema and pseudophakic cystoid macular edema. It was able to accurately diagnose the underlying pathology in 90%-96% of cases. However, actually using the trained classifier required dedicated software and advanced technical skills which hindered its accessibility to most clinicians. Our aim was to package the classifier in an easy to use web-tool and validate the web-tool using a new cohort of patients.

METHODS

We packaged the classifier in a web-tool intended for use on a personal computer or mobile phone. We first ensured that the results from the web-tool coincide exactly with the results from the original algorithm and then proceeded to test it using data of 14 patients.

RESULTS

The etiology was accurately predicted in 12 out of 14 cases (86%). The cases with diabetic macular edema were accurately diagnosed in 7 out of 7 cases. Of the pseudophakic cystoid macular edema cases, 5 out of 6 were correctly interpreted and 1 case with a mixed etiology was interpreted as pseudophakic cystoid macular edema. Variable input was reported to be easy and took on average 7 ± 3 min.

CONCLUSION

The web-tool implementation of the classifier seems to be a valuable tool to support research into this field.

Refractive surgery in the late adulthood and adolescent age groups

PURPOSE

Most refractive surgeries are performed in the young-adult age group, and less is known about the clinical outcomes of patients in late adulthood and of adolescents. The purpose of this study was to describe the outcomes of refractive surgery in patients over the age of 60 years and under the age of 18 years compared with a control group of patients aged 20-40 years.

METHODS

This retrospective cohort analysis consisted of 64,970 consecutive cases of 32,074 patients who underwent laser-assisted in situ keratomileusis and photorefractive keratectomy during a 10-year period in a single center. The populations were characterized, and a comparison of safety, efficacy, and retreatment rates was performed following propensity score matching, separately for hyperopic and myopic treatments.

RESULTS

Included in the analysis after matching were 143 patients above the age of 60, 608 patients aged < 18, and 2313 patients aged 20-40. Older patients undergoing hyperopic treatments had worse safety (0.95 ± 0.1 versus 0.99 ± 0.2, P = 0.023) and efficacy indices (0.89 ± 0.2 versus 0.97 ± 0.2, P = 0.004) compared with young adults. Lower efficacy was also seen in myopic treatments (0.88 ± 0.3 versus 0.97 ± 0.2, P = 0.001). Higher retreatment rates were also seen among older adults (6.2% versus 2.5%, P = 0.044 in hyperopic treatments, 11% versus 1.1%, P < 0.001 in myopic treatments). In adolescents, the safety and efficacy outcomes were slightly better compared with patients aged 20-40, with lower retreatment rates (1% versus 2.7%, P = 0.001).

CONCLUSIONS

Refractive surgery in the late adulthood population of our cohort was a relatively safe procedure, yet manifesting lower efficacy and requiring more retreatments. In adolescents, results were comparable to those achieved in young adults.

The effect of sildenafil on retinal blood velocity in healthy subjects

Purpose

It has been suggested that Sildenafil may have beneficial therapeutic effects in the treatment of neurodegenerative disorders. The retinal circulation is of significant interest as a marker of cerebral vascular disease since the retinal and cerebral vasculatures share many morphological and physiological properties, yet only the retinal circulation can be directly visualized. Therefore, our aim was to assess the change induced by Sildenafil on retinal blood velocity.

Methods

Retinal flow velocity was measured 0.5, 3 and 6 h following administration of 100 mg of Sildenafil using the Retinal Function Imager.

Results

No clinical change in either systemic blood pressure or retinal flow velocities were observed. However, when controlling for heart rate and blood pressure, a significant drop in venous flow velocity 6 h following treatment (mean drop 0.3 ± 0.07; 95% CI: 0.44–0.56, P = 0.023) was revealed.

Conclusions

In healthy volunteers, retinal venous flow velocity was significantly reduced at the 6-h time point following Sildenafil treatment. No effect was observed on arterial retinal flow velocity.

THUR 174 The magnify-ms study: mavenclad® tablets in active rms

Authors Disclaimer: http://medpub-poster.merckgroup.com/ABN2018DISC_MAGNIFY.pdf

Background

Cladribine tablets (CT) improve clinical and MRI outcomes in patients with active RMS, with significant differences versus placebo after 24 weeks.

Objective

Describe the design of a study to assess the onset of CT’s clinical and MRI effects in patients with active RMS.

Methods

MAGNIFY-MS is a 2 year prospective Phase IV trial (including approximately 100 centres in Europe). Eligible patients will receive two years treatment with CT 3.5 mg/kg cumulative dose. Frequent MRI assessments (including lesion count, lesion volume, brain volume and MTR) will be performed at screening, baseline and 1, 2, 3, 6, 12, 15, 18 and 24 months. Various T- and B-cell subtype counts and functional profiling (eg cytokine production) will be assessed. Clinical outcomes will include changes in cognition (SDMT), disability (EDSS/KFS, 9HPT, T25FW), relapses, NEDA, NEDAP and safety at timepoints up to 24 months.

Results

Aim recruit 300 patients. Primary endpoint: change in the count of combined unique active lesions at end of 6 months versus baseline. Final outcomes expected in 2021.

Conclusions

MAGNIFY-MS will provide important information on the effects of CT, including early MRI changes, insights into effects on a range of disability and cognition markers, and detailed characterization of immune cell reconstitution.

Disclosure statement

This study was sponsored by EMD Serono, Inc., a business of Merck KGaA, Darmstadt, Germany (in the USA), and Merck Serono SA – Geneva, an affiliate of Merck KGaA Darmstadt, Germany (ROW).

Reduction of intraocular pressure after bariatric surgery

PURPOSE

To investigate the effects of bariatric surgery on intraocular pressure (IOP).

METHODS

We prospectively enroled consecutive obese patients who underwent a laparoscopic sleeve gastrectomy procedure. We measured IOP prior to and 3-6 months following surgery and recorded medical and demographical parameters.

RESULTS

Thirty-two patients completed all evaluations. Mean age was 40.5 ± 12 and 24 (75%) were men. Following surgery, mean body-mass index (BMI) decreased from 42 ± 6 to 31 ± 8 (p < 0.001). The mean IOP decreased from 16.9 ± 4 mmHg to 14.1 ± 3 mmHg (p < 0.001). The extent of IOP reduction was correlated with the baseline IOP (Pearson r = 0.737, p < 0.001) and central corneal thickness (Pearson r = 0.453, p = 0.010).

CONCLUSION

In a cohort of obese individuals undergoing sleeve gastrectomy, there was a significant decrease in IOP measured 3-6 months after the procedure. Our results suggest that significant weight loss could have beneficial effects on IOP in obese individuals with ocular hypertension which might enable avoidance of antiglaucoma medications. The high likelihood of a reduction in IOP should be taken into account when considering bariatric surgery in such patients.

Neural correlates of gait variability in people with multiple sclerosis with fall history

BACKGROUND AND PURPOSE

The aim was to investigate the association between step time variability and related brain structures in accordance with fall status in people with multiple sclerosis (PwMS).

METHODS

The study included 225 PwMS. Whole-brain magnetic resonance imaging was performed with a high-resolution 3.0 T magnetic resonance scanner in addition to volumetric analysis based on 3D T1-weighted images using the FreeSurfer image analysis suite. Step time variability was measured with an electronic walkway. Participants were defined as 'fallers' (at least two falls during the previous year) and 'non-fallers'.

RESULTS

In all, 105 PwMS were defined as fallers and had a greater step time variability compared to non-fallers [5.6% (SD = 3.4) vs. 3.4% (SD = 1.5); P = 0.001]. MS fallers exhibited a reduced volume in the left caudate and both cerebellum hemispheres compared to non-fallers. On using a linear regression analysis no association was found between gait variability and related brain structures in the total cohort and the non-fallers group. However, the analysis found an association between the left hippocampus and left putamen volumes with step time variability in the faller group: P = 0.031, 0.048, respectively, controlling for total cranial volume, walking speed, disability, age and gender. Nevertheless, according to the hierarchical regression model, the contribution of these brain measures to predict gait variability was relatively small compared to walking speed.

CONCLUSIONS

An association between low left hippocampal, putamen volumes and step time variability was found in PwMS with a history of falls, suggesting that brain structural characteristics may be related to falls and increased gait variability in PwMS.

Prenatal Ultrasonographic Diagnosis of Cataract: In Utero Manifestations of Cryptic Disease

PURPOSE

 To report and review our experience with antenatal evaluation for fetuses diagnosed with congenital cataract.

MATERIALS AND METHODS

 We retrospectively identified pregnancies diagnosed with fetal cataract during antenatal ultrasound. Evaluation of fetal eyes included intraocular anatomy and biometry. Data on fetal malformations, serology and fetal karyotype were collected.

RESULTS

 8 cases, identified over the course of 10 years, were reviewed. Week 15 was the mean time for diagnosis (range 11 - 34). Extraocular anomalies were demonstrated in 6 cases (central nervous system, cardiac and renal systems). Additional intraocular abnormalities were detected in two cases: one fetus had persistent hyperplastic primary vitreous and another had bilateral retinal detachment. All cases but one involved cataracts in both eyes. The unilateral case was associated with microphthalmic aphakia. All cases had negative serology for TORCHs. 7 out of the 8 fetuses were terminated. The only one who survived developed in utero cataracts secondary to maternal steroid therapy. He underwent bilateral cataract extraction during the first weeks of life and ophthalmologic evaluation at 2 years of age was unremarkable, without any visual impairment.

CONCLUSION

 In most cases, fetal cataract was associated with additional abnormalities, both intra- and extra-ocular. In instances when cataracts are isolated, we suggest conducting a detailed and thorough in utero ophthalmic examination in order to improve antenatal parental counselling.

Frequency, comprehension and attitudes of physicians towards abbreviations in the medical record

AIMS

Abbreviations are common in the medical record. Their inappropriate use may ultimately lead to patient harm, yet little is known regarding the extent of their use and their comprehension. Our aim was to assess the extent of their use, their comprehension and physicians' attitudes towards them, using ophthalmology consults in a tertiary hospital as a model.

METHODS

We first mapped the frequency with which English abbreviations were used in the departments' computerised databases. We then used the most frequently used abbreviations as part of a cross-sectional survey designed to assess the attitudes of non-ophthalmologist physicians towards the abbreviations and their comprehension of them. Finally, we tested whether an online lecture would improve comprehension.

RESULTS

4375 records were screened, and 235 physicians responded to the survey. Only 42.5% knew at least 10% of the abbreviations, and no one knew them all. Ninety-two per cent of respondents admitted to searching online for the meanings of abbreviations, and 59.1% believe abbreviations should be prohibited in medical records. A short online lecture improved the number of respondents answering correctly at least 50% of the time from 1.2% to 42% (P<0.001).

CONCLUSIONS

Abbreviations are common in medical records and are frequently misinterpreted. Online teaching is a valuable tool for physician education. The majority of respondents believed that misinterpreting abbreviations could negatively impact patient care, and that the use of abbreviations should be prohibited in medical records. Due to low rates of comprehension and negative attitudes towards abbreviations in medical communications, we believe their use should be discouraged.

Intraocular Pressure Spikes following Neodymium-doped Yttrium Aluminum Garnet Laser Capsulotomy: Current Prevalence and Management in Israel

Aim

The current treatment for posterior capsular opacification (PCO), neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy, may lead to increased intraocular pressure (IOP). Our aim was to survey routines in the management of IOP spikes and to identify the rate of IOP spikes following prophylactic apraclonidine treatment.

Materials and methods

A survey questionnaire among ophthalmologists and a retrospective registry review was used. Patients were administered apraclonidine 0.5% prior to capsulotomy. The IOP was measured before and 1 hour postprocedure.

Results

A total of 71% of responders (n = 45) routinely prescribe topical IOP-lowering medication and 82% routinely measure IOP before or after capsulotomy. The registry analysis included 87 eyes of 75 patients. Mean IOP decreased by 0.9 ± 3.3 mm Hg (p = 0.01, range: -6 to 10) following capsulotomy. No patient reached IOP values above 21 mm Hg following the procedure, with 3.4 and 1.1% of patients demonstrating an IOP elevation of more than 3 and 5 mm Hg respectively. No association was found between number of laser shots, mean laser power, or comorbid conditions, such as diabetes, hypertension, or glaucoma status with posttreatment IOP.

Conclusion

Most ophthalmologists surveyed routinely prescribe prophylactic IOP-lowering medication and measure IOP before or after capsulotomy. Mean IOP remained clinically stable following capsulotomy with prophylactic apraclonidine instillation, and no patient reached IOP values above 21 mm Hg. Differences in laser delivery or comorbid conditions were not associated with posttreatment IOP. Considering that no patient demonstrated a clinically significant IOP spike following prophylactic apraclonidine instillation, perhaps routine measurement of IOP following primary Nd:YAG laser may be reserved for high-risk patients only.

Clinical significance

In this work, we showed the prophylactic effect of apraclonidine 0.5% and suggest that measuring IOP after the procedure is necessary only in certain high-risk cases, possibly helping to reduce workload and patient waiting time and improving quality of service.

How to cite this article

Achiron A. Intraocular Pressure Spikes following Neodymium-doped Yttrium Aluminum Garnet Laser Capsulotomy: Current Prevalence and Management in Israel. J Curr Glaucoma Pract 2017;11(2):63-66.

Treatment of retinal artery occlusion using transluminal Nd:YAG laser: a systematic review and meta-analysis

AIMS

To review clinical experience, efficacy, and safety of transluminal Nd:YAG laser embolectomy/embolysis (TYE) for retinal artery occlusion.

METHODS

 Electronic databases were searched for all published clinical studies and case-reports reporting on TYE in central (CRAO) or branch (BRAO) retinal artery occlusion. Individual patient data was evaluated in a weighted pooled analysis.

RESULTS

Sixty-one cases were reported, 47 with BRAO and 14 with CRAO. Visual acuity (VA) at onset averaged 20/252 (1.1 LogMAR) and improved following the procedure to 20/47 (0.37 LogMAR) at first follow-up (avg. 6 days, P < 0.001) and to 20/30 (0.18 LogMAR) at last reported follow-up (avg. 1.1 years, P = 0.02). Patients with worse VA (<20/200) improved further (12 vs. three lines, P < 0.001). VA was not improved when using higher pulse energies (≥ 2.4 mJ) which were associated with more vitrectomies. In a weighted analysis vitreous/sub-retinal hemorrhage was estimated to occur in 54% of cases and required vitrectomy in 18% of cases.

CONCLUSIONS

TYE was followed by significant visual improvement in the vast majority of cases, including CRAO, and was frequently associated with vitreous hemorrhage. Patients with poor visual acuity appear to benefit further and higher pulse energies may be detrimental. Lack of randomization and intrinsic biases prevent any definite conclusions regarding the benefits and further research is warranted.

Uveitis-Glaucoma-hyphema Syndrome

After 20 years of catarct surgery, a 66 years old man has found to have subluxtaed intraocular lens with satbilizing haptic protuding through the pupil.

Corneal Staining and Hot Black Tea Compresses

BACKGROUND

Warm compresses are widely touted as an effective treatment for ocular surface disorders. Black tea compresses are a common household remedy, although there is no evidence in the medical literature proving their effect and their use may lead to harmful side effects.

OBJECTIVES

To describe a case in which the application of black tea to an eye with a corneal epithelial defect led to anterior stromal discoloration; evaluate the prevalence of hot tea compress use; and analyze, in vitro, the discoloring effect of tea compresses on a model of a porcine eye.

METHODS

We assessed the prevalence of hot tea compresses in our community and explored the effect of warm tea compresses on the cornea when the corneal epithelium's integrity is disrupted. An in vitro experiment in which warm compresses were applied to 18 fresh porcine eyes was performed. In half the eyes a corneal epithelial defect was created and in the other half the epithelium was intact. Both groups were divided into subgroups of three eyes each and treated experimentally with warm black tea compresses, pure water, or chamomile tea compresses. We also performed a study in patients with a history of tea compress use.

RESULTS

Brown discoloration of the anterior stroma appeared only in the porcine corneas that had an epithelial defect and were treated with black tea compresses. No other eyes from any group showed discoloration. Of the patients included in our survey, approximately 50% had applied some sort of tea ingredient as a solid compressor or as the hot liquid.

CONCLUSIONS

An intact corneal epithelium serves as an effective barrier against tea-stain discoloration. Only when this layer is disrupted does the damage occur. Therefore, direct application of black tea (Camellia sinensis) to a cornea with an epithelial defect should be avoided.

Pseudoexfoliation: An Ocular Finding with Possible Systemic Implications

Pseudoexfoliation syndrome (PES) is a common age-related disorder affecting 60-70 million people worldwide. Patients with PES have abnormal production and deposition of fibrillar material in the anterior chamber of the eye. These exfoliated fibrils, easily detected by ocular slit-lamp examination, have also been found to exist systematically in the skin, heart, lungs, liver and kidneys. Recently, myriad studies have associated PES with systemic conditions such as increased vascular risk, risk of dementia and inflammatory state. We review here the most current literature on the systemic implications of PES. Our aim is to encourage further studies on this important clinical entity.

Intraocular pressure measurement after DSAEK by iCare, Goldmann applanation and dynamic contour tonometry: A comparative study

PURPOSE

Corneal thickness inevitably increases following Descemet's stripping automated endothelial keratoplasty (DSAEK), owing to the addition of a donor graft. The current study compares different devices in assessing post-DSAEK intraocular pressure (IOP).

METHODS

We compared IOP values measured by the Goldmann tonometry (GAT), iCare rebound tonometry (iCare) and Pascal dynamic contour tonometry (PDCT) in eyes following DSAEK. Agreement between measurements was calculated with correlation analysis and Bland-Altman plots. Effects of keratometry, central, thickness (CCT), endothelial cell density (ECD) and axial length on IOP measurements were assessed with Pearson's correlation.

RESULTS

Twenty eyes of 20 patients (mean age 74.3±14.4, 14 females) post-DSAEK were included in this study. There was a high concordance between the IOP readings obtained by the three devices: a strong and significant correlation was found between GAT and PDCT (r=0.94, P<0.001) GAT and iCare (r=0.86, P<0.001) and iCare with PDCT (r=0.81, P<0.001). However, the iCare measurements were significantly and consistently lower than that obtained with GAT (ΔIOP=1.68±2.0, P=0.002, 95% CI: 0.7-2.6) and with PDCT (ΔIOP=1.61±2.5, P=0.01, 95% CI: 0.4-2.8). CCT, ECD, CCT, AXL, corneal curvature or astigmatism did not influence IOP measurement by any instrument.

CONCLUSIONS

IOP measurement with three different techniques (applanation, rebound and dynamic contour) showed good correlations, despite an increased corneal thickness following DSAEK. However, the iCare, which is based on a rebound tonometry showed significant lower IOP then the two other methods. This should be taken into account when evaluating patients post DSAEK.