Accommodative Facility Research Articles

Correlations between clinical measures and symptoms: Report 2: Accommodative and vergence measures with symptoms

AimThe aim of this study was to explore associations among clinical measures of accommodation and vergences with symptoms, which could facilitate the validation of the Convergence Insufficiency Symptoms Survey to screen for deficient clinical measures. MethodsUsing a multi-stage random cluster sampling, 1211 high school students (481 males and 730 females) between 13 and 18 years of age were selected and examined. Visual acuity, stereoacuity and suppression, refractive errors, near point of convergence, heterophoria and fusional vergences, as well as, amplitude of accommodation, accommodative response, facility and relative accommodation were evaluated. The validity of the Convergence Insufficiency Symptoms Survey to distinguish between children with and those without anomalies in the clinical measures were characterized using the Receiver Operation Curve, sensitivity and specificity of the tests. ResultsThe overall mean and standard deviation for symptoms score was 27.38 ± 11.04. Deficient accommodative measures revealed worse symptoms scores than did deficient vergence measures and children with deficient clinical measures had significantly higher mean symptoms scores. (p = 0.001) However, the correlations between defective clinical measures and symptoms were significant but relatively weak. The Receiver Operation Curve showed that the clinical measures with the highest sensitivities using the CISS (≥16) were: reduced amplitude of accommodation 0.63, 95% Confidence interval, 0.59−0.68%) accommodative facility 0.62 (95% Confidence interval, 0.58−0.67) and near point of convergence 0.60 (95% Confidence interval, 0.53−0.67). ConclusionDeficient clinical measures and symptoms of asthenopia are prevalent and correlated in the sample of school children studied. Overall, findings suggest that high school children with deficient clinical measures may be symptomatic when they perform intense near task compared to those without deficiencies. In addition, although validated for convergence insufficiency, the Convergence Insufficiency Symptoms Survey could barely distinguish between children with and without defective clinical measures. Findings highlight the need for and provide baseline data towards possible validation of a fast and reliable screening tool for vision anomalies. Further studies on similar populations are needed to confirm these findings and add to knowledge base.

Research on a new type of buffering valve for vehicle shifting

The traditional buffering valve for vehicle shifting mainly relies on the throttle hole and spring to control the pressure in the clutch. However, its accommodative facility and adaption are inferior. Therefore, two–dimensional (2D) digital technology is proposed to be applied to the vehicle shift buffering area, and the 2D digital buffering valve is designed. This study introduces the structure and working principle of the 2D digital buffering valve and establishes the mathematical model of the 2D digital buffering valve. The classical proportional–integral–differential control algorithm is adopted and Matlab/Simulink is used to simulate its control model. Finally, an experimental study is carried out. The study results show that when the frequency is 50 Hz, the amplitude of the valve output pressure decays to −3 dB, and when the frequency is 60 Hz, the phase of the valve output pressure lags by 90°. The output of the 2D digital buffering valve meets the requirement of the change of the oil pressure in the clutch during the vehicle shifting process. The control precision of its buffering pressure characteristic reaches 15%. The simulation and test results of the buffering valve are consistent, which verifies the correctness of the simulation model.

Accommodation changes after strabismus surgery due to anterior ciliary vessel disruption.

To evaluate monocular accommodation changes after strabismus surgery with and without anterior ciliary vessel preservation. Sixty patients with horizontal concomitant strabismus who were scheduled to undergo monocular strabismus surgeries were randomly divided into two groups: A (without anterior ciliary vessel preservation) and B (with anterior ciliary vessel preservation). Group A was further divided into groups A1 (surgical eyes without anterior ciliary vessel preservation) and A2 (corresponding nonsurgical eyes). Group B was further divided into groups B1 (surgical eyes with anterior ciliary vessel preservation) and B2 (corresponding nonsurgical eyes). Monocular accommodative amplitude (AA) and accommodative facility (AF) were evaluated before and 1day after the surgery to assess accommodation. In groups A2, B1, and B2, the AA and AF values showed no significant difference preoperatively or postoperatively. However, compared with preoperative values, both the postoperative AA and AF values were significantly reduced in group A1. Strabismus surgery without anterior ciliary vessel preservation reduces monocular accommodation, whereas strabismus surgery with anterior ciliary vessel preservation protects accommodation.

Feasibility of optical quality analysis system for the objective assessment of accommodation insufficiency: a phase 1 study

PurposeTo assess differences in a new objective metric obtained with a double-pass technique between a group with accommodation insufficiency (AI) and a control group and to explore the diagnostic capabilities of this new tool in comparison to conventional procedures. MethodsRetrospective cross-sectional case-control phase 1 study. Two groups with ages ranging from 8 to 18 years were recruited: AI and control group. The diagnostic criterion of AI was based on monocular accommodative amplitude (AA), 2 D below Hofstetter’s calculation for minimum AA, and monocular accommodative facility (MAF), failing with minus lens and cut-off at ≤ 6 cycles per minute. Accommodative response with a double pass device (HD Analyzer, Visiometrics) was measured, performing an evaluation from +1.00 D to −3.50D (−0.5D steps), offering the width of the profile at 50% (WP) in minutes of arc. ResultsDifferences were found between groups for the AA, MAF and MEM retinoscopy (p < 0.0001, p < 0.001, p = 0.037). The discriminative capacity of MEM retinoscopy for AI diagnosis was significant and the cut-off that maximized the sensitivity and specificity was > 0.5 D. Considering WP 50% in different points, the discriminative AI diagnosis capacities for the points of 2.0 D and 2.50 D were significant (ROC-AUC 0.78; p = 0.03 and p = 0.02). ConclusionsDouble-pass system metric differed between patients with AI and control group, therefore the aim of a Phase I study was achieved. Further steps with higher sample sizes are required to evidence if the system really provides any advantage versus conventional methods in the diagnosis of AI.

Accommodation is unrelated to myopia progression in Chinese myopic children

This study shows accommodative accuracy and distance accommodation facility in myopic children do not play a role in myopia progression. In 144 subjects, the monocular distance accommodative facility (DAF) and continuous accommodative stimulus–response curves (ASRCs) were measured at the enrolment. Retrospective and prospective refraction with regard to the enrolment visit were obtained from the outpatient database system based on noncycloplegic subjective spherical equivalent refraction (SER). The rate of myopic progression at enrolment was the first derivative of the Gompertz function, which was fitted with each subject's longitudinal refractive error data, including at least four records of SER with an interval of more than 6 months between each visit. A mixed linear model for multilevel repeated-measures data was used to explore the associations between the rate of myopia progression and accommodative parameters. The mean rate of myopia progression at enrolment was -0.61 ± 0.31 D/y with a mean age of 12.27 ± 1.61 years. By adjusting for age and SER, it was shown that the myopic progression rate was not associated with the accommodative lag (F = 0.269, P = 0.604), accommodative lag area (F = 0.086, P = 0.354), slope of ASRC (F = 0.711, P = 0.399), and DAF (F = 0.619, P = 0.432).

Diversity and abundance of wild mammals between different accommodation facilities in the Kwakuchinja Wildlife Corridor, Tanzania

Most of the wildlife corridors in Tanzania have been threatened by extensive human activities, including the establishment of tourist's facilities. However, less attention has been paid to the degree at which tourist accommodation affects the abundance and diversity of wild mammals in wildlife corridors. This study assessed the changes in abundance and diversity of wild mammals in relation to proximity to tourist lodges and tented camps in Kwakuchinja Wildlife Corridor. All wild mammals around four randomly selected accommodation facilities that include two lodges and two tented camps in the Kwakuchinja Wildlife Corridor were counted. In order to count animals, four 2-km transects were laid in each of the selected accommodation facilities and all wild mammals observed within 500 m width were recorded. The total number of each individual species recorded in all four transects was used to determine abundance of mammals in each accommodation facility. After that, we used Shannon-Wiener diversity index to determine species diversity. Generalized linear models were used to assess the variation in abundance and diversity between the two types of tourist accommodation facilities. We found a higher abundance of mammals around tented camps than lodges, while diversity decreased when moving away from those tourist accommodation facilities (for both lodges and tented camps). With the current efforts of the Tanzanian government to revive the vanishing wildlife corridors, understanding how different types of tourist accommodations affect mammalian populations is crucial to inform the sustainable and environmentally sound tourism investments in wildlife corridors and other biodiversity areas.

The Accommodation Response and Facility between Children and Young Adults

Tonic accommodation decreased with age among children. In young adults, late-onset myopia will develop due to occupational near vision demands. This study aims to investigate the accommodation response and facility between children and young adults, in emmetrope (non-myopic) and myope group. The accommodation response and facility of young adults and children were measured using monocular estimation method (MEM), monocular accommodative facility (MAF) and binocular accommodative facility (BAF) with an exposure of near task for 15 minutes. Near task has significantly increased the lag of accommodation in all groups (p&lt;0.05). However, the accommodation facility was not affected by near work in all groups (p&gt;0.05). Keywords: accommodation response, accommodation facility, myopes, emmetropes. eISSN: 2398-4287© 2020. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open access article under the CC BYNC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning &amp; Surveying, Universiti Teknologi MARA, Malaysia. DOI: https://doi.org/10.21834/ebpj.v5i14.2168

Visio-spatial skills in athletes: comparison of rugby players and non-athletes

Research pertaining to the superiority of athletes’ visio-spatial expertise when compared to non-athletes is conflicting. This discrepancy may arise due to a superiority in athletes in only specific visio-spatial skills (VSS) and not all aspects of vision. The aim of this study was to discern whether rugby players have superior VSS/expertise in comparison to non-athletes, when comparing six visual skills (accommodation facility, saccadic eye movement, speed of recognition, peripheral awareness, visual memory and hand–eye coordination). The participants underwent an optometric assessment, after which the VSS components of non-athletes and premier league rugby players were assessed by using six different existing tests namely; the Hart Near Far Rock, saccadic eye movement, evasion, accumulator, flash memory and ball wall toss tests. A statistically significant (p ≤ .05) difference existed between rugby players and non-athletes for five out of the six tests. Conversely, no real evidence is shown that visual memory differs between rugby players and non- athletes (p = .599). This study found that rugby players have an enhanced accommodation facility, saccadic eye movements, speed of recognition, peripheral awareness and hand–eye coordination, but not visual memory, when compared to non-athletes. These findings of a superiority of rugby players in specific VSS have broad implications for theories of sport vision, how best to select tests and in the development of sport-specific VSS testing batteries.

Effects Of Home-Based Convergence Insufficiency Vision Therapy On Accommodation Among School Going Children

Effects of home-based convergence insufficiency vision therapy on accommodation among school going children &#x0D; Wekesa Andrew1, Wanzala Maximilla1&#x0D; 1Masinde Muliro University of Science and Technology Kakamega, Kenya.&#x0D; &#x0D; Abstract &#x0D; Background: Convergence and accommodation are always yoked together and any adjustment on the former affects the later. The most effective treatment for convergence insufficiency (CI) is vision therapy.&#x0D; Aim/Purpose: To determine the effects of home-based vision therapy on accommodation in school-going with CI attending the Masinde Muliro University Academic Vision Center in Kenya.&#x0D; Methods: A clinical experimental design involving 23 participants with the mean age of 14±2.4 years, were recruited into the study, however, only 18 were assessed after the therapy. The study took 9 weeks thus majority lost contact while others moved out of the town. Home-based vision therapy which is undertaken at home using a pencil or broke strings. During the therapy, accommodative values were monitored which were; negative relative accommodation, positive relative accommodation, dynamic accommodation, accommodative facility and near point of accommodation. Paired t-test used to compare mean values before and after the therapy.&#x0D; Results: The mean value of negative relative accommodation (NRA) before (mention what the mean values were here) and after (mention what the mean values were here) home-based therapy was statistically significant (p=0.01). However, the mean values before and after home-based therapy for the near point of accommodation (NPA), dynamic (Lag), relativity (PRA) and facility (MAF) showed no difference (p&gt; 0.05). The mean value of the NRA before and after office-based vision therapy was statistically significant (p=0.01).&#x0D; Conclusion: The use of home-based vision therapy for the patients with CI had significant effects on accommodation changing from a lower limit to average after the therapy.&#x0D; &#x0D; Keywords: Convergence insufficiency, Accommodation, Home-based vision therapy.

Travellers’ top comments during the COVID-19 pandemic in Botswana

ABSTRACT This article is an appraisal of the ongoing COVID-19 pandemic in Botswana. The article outlines literature in the context of impacts and reactions to the pandemic. The rest of the article builds upon the comments retrieved from TripAdvisor as the pandemic unfolds. Using text mining, a rapid assessment of travellers’ reflections of the pandemic on TripAdvisor is provided. The findings demonstrate the limited use of themes such as fear and anxiety or trip disruptions that can be associated with the pandemic, among travellers, who had stayed at varied accommodation facilities in the country. Instead, most of the travellers provided compliments, recommendations and revisit intentions, gave narrations of their trip experiences, game viewing and hunting experiences and were impressed with the location and overall appeal of the facilities. Such findings to some extent allay the uncertainties associated with travel in the country during the pandemic. The findings also emphasise the importance of accommodation facility attributes such as location, even during a crisis.

Receiver operating characteristic curve analysis of clinical signs for screening of convergence insufficiency in young adults.

Convergence insufficiency (CI) is a dysfunction of binocular vision that is associated with various signs and symptoms in near work. However, CI screening is performed less frequently in adults than in children. We aimed to evaluate the ability of screening tests to discriminate CI from other binocular vision anomalies and normal binocular vision in young adults. One hundred eighty-four university students (age, 18-28 years) who underwent an eye examination due to ocular discomfort were included. Near point of convergence (NPC), phoria, accommodative amplitude, fusional vergence, the ratio of accommodative convergence to accommodation, relative accommodation, binocular accommodative facility, vergence facility, and the values corresponding to Sheard's and Percival's criteria were evaluated. Receiver operating characteristic (ROC) curve analysis for each test was also performed. The prevalence of CI ranged from 10.3% to 21.2%, depending on the signs and the presence of CI associated with accommodative disorders. Assessments based on NPC, Sheard's criterion, and Percival's criterion showed high discriminative ability, with the ability being higher between the CI and normal binocular vision groups than between the CI and non-CI groups. Sheard's criterion showed the highest diagnostic performance in discriminating CI with three signs from the non-CI group. The cut-off values were 7.2 cm for NPC, -0.23 to 1.00 for Sheard's criterion, and -4.00 to -2.33 for Percival's criterion. Our results suggest that the use of Sheard's criterion with NPC shows high performance for screening of CI.

Location Characteristics of Accommodation Facilities Selected by Tourists in Surakarta City, Central Java Province

The city of Surakarta is one of the cultural and historical tourist destinations that continues to develop in Indonesia. The trend of an increase in the number of tourists in 2016-2018 has led to the emergence of many accommodation facilities in the city of Surakarta. Differences in location characteristics in each accommodation facility will affect tourists in choosing accommodation facilities. This study aims to determine the characteristics of the location of accommodation facilities chosen by domestic and foreign tourists in the city of Surakarta, as well as the relationship between the characteristics of the location of accommodation facilities with the characteristics of tourists based on the age and place of origin of tourists. This study uses a spatial comparison analysis method and uses a chi-square statistical analysis to see the relationship between variables, such as the characteristics of the location of accommodation facilities and characteristics of tourists. The results of this study indicate that the location characteristics of the accommodation facilities chosen by foreign and domestic tourists are different. Foreign tourists tend to choose star hotels, while for domestic tourists the choice varies, namely star hotels and non-star hotels. In addition, there is a relationship between the characteristics of domestic tourists with the characteristics of the location of selected accommodation facilities, while for the characteristics of foreign tourists there is no relationship with the characteristics of the location of selected accommodation facilities.

Prevalence of Ocular and Visual Anomalies in Students with Autism Spectrum Disorder (ASD)

Purpose: To determine the prevalence of ocular and visual anomalies in students with Autism Spectrum Disorder (ASD). Methods: This case-series in 2015-16 included students with ASD of two special schools of Bangalore, India. Comprehensive ocular and vision examination also included accommodation by dynamic retinoscopy and convergence. The amplitude of accommodation was calculated by Hofstetter minimum formula. The accommodative facility was measured by referring to the cycles of accommodative flippers, used ± 2.50D and 14 cycles/min considered as normal. Saccades were tested using Marsden ball movements. Additional eye testing at our institute was with Vision therapy system, ocular motility testing and alternate prism cover test. Result: The 120 students with ASD had a mean age of 12.9 ± 1.7 years. They included autism 58 (48.3%), ASD 27 (22.5%) and other 34 (28.3%). Spectacles correction was needed in 62 (51.7%) students. Refractive error included myopia (57; 92%), hyperopia (5; 8%), myopic astigmatism (3; 4.8%), and mixed astigmatism (2; 3.2%). The compliance of spectacle wear was 12/62 (19.4%) only. Strabismus was seen in 68 (56.7%) students. Accommodative convergence was 4 to 28 mm. Non-accommodative convergence was 4 to 37 mm. Pursuit movements were poor in 35 (29.2%), average in 39 (32.5%), good in 46 (38.3%) students. The saccadic eye movements were good in 100 (83.3%), average in 15 (12.5%) and poor in 5 (4.2%) students. Conclusion: More than half of students with ASD had at least one ocular morbidity. The commonest was refractive errors followed by strabismus. Periodic and comprehensive ocular assessment of autistic students is recommended.

A Case of Accommodative Insufficiency with Vergence Disorder in a 17-Year Old Student

Accommodation Insufficiency (AI) is a condition in which a patient has an inability to focus or maintain focus at near. AI is mostly observed to occur with a vergence problem especially convergence insufficiency due to the close link between accommodation and convergence system of the eyes. Common symptoms seen in AI are diplopia, asthenopia and difficulty reading at near. Several management options are available including plus lenses for near work, optometric vision therapy and monitoring. A 17-year-old lady presented to the eye department with eyestrains, frontal headache, blurry vision at near with reading difficulties. According her, this problem started in 2018. Visual acuity (VA) for both distance and near was measured. Detailed anterior and posterior segments assessment revealed no anomalies, but binocular assessment showed reduced Amplitude of Accommodation (AOA), increased lag of accommodation, reduced Monocular Accommodative Facility (MAF) and Binocular Accommodative Facility (BAF), reduced Positive Relative Accommodation (PRA) and receded Near Point of Convergence (NPC). Based on the patient’s complaint and what the assessment revealed, accommodative insufficiency with vergence disorder was made. Vision therapy and distance optical correction were prescribed to manage the problem. Accommodative Insufficiency can be treated effectively by an in-office/home-based program. The repetition of appropriate optometric vision therapy procedures at home will help resolve a patient’s maladaptive visual condition over time.

Rehabilitation and Reinforcement of Ferroconcrete Walls with Reinforced Pilasters

The article is focused on renovation, rehabilitation and reinforcement of high ferroconcrete walls. It tries to point out the experience of experts in solving problems with high ferroconcrete walls. During a revitalization of buildings of a military accommodation facility in Brno with basement and connecting corridors of an average height of 25 m, degradation of concrete, locally missing reinforcement and poor-quality concrete mixtures, the strength class of which varied between C8/10–C10/12, were found in these corridors. Along the height of the pilasters, the structure also showed the signs of torsion and it was assessed the structure also needs to be strengthened/reinforced besides the rehabilitation. The reinforcement structure had to be built from the very foundation of the building, it is linked to the existing wall and has three cascade levels. For the first two parts, a construction pit has been created with a Berliner wall, and these parts reach below the modified terrain, are reinforced with concrete reinforcement according to the structural project, concreted with cast concrete, and the foundation is reinforced with deep-based construction. The second and the third parts of the cascade stretch from the modified terrain between the pilasters to the top and they are made with a two-stage shotcrete technique, the first one has inbuilt concrete reinforcement with welded wire mesh and the second one composite mesh anchored by helical reinforcement without static effect. In terms of the damage of the structure, carbon fibre wrapping technique or grouting of the existing ferroconcrete structure was also used in the affected areas. The article also includes photo documentation of the repairs and structural damage prior to them.

Accommodative Changes with Center-Near Multifocal Contact Lenses in Young Adults with Accommodative Infacility

Purpose : To evaluate changes in accommodative function after near works in young myopes with accommodative infacility fitted with center-near multifocal soft contact lenses. Methods : Thirty-one soft contact lens wearers were participated and divided into the accommodative infacility group and normal group according to the accommodative facility. Subjects were fitted with single vision contact lenses (SVCLs) and center-near mid-add multifocal soft contact lenses (MFCLs). In case of MFCLs wearing, accommodative functions were measured after more than 7 days of adaptation. The amplitude of accommodation, near point of convergence, accommodative facility and vergence facility were measured after watching video using a smartphone for inducing accommodative burden for 30 minutes. Results : Among the subjects, twenty-four were normal in accommodative facility and seven were accommodative infacility. In young adults group with accommodative infacility, the near point of accommodation after watching video, was significantly increased with SVCLs(p=0.012) and no difference with MFCLs compared with before watching video. And the near point of convergence with MFCLs after watching video was significantly shorter than that with SVCLs, and shorter than before watching video(p=0.009), and accommodative facility with MFCLs was statistically significant increased compared with SVCLs, and higher than that of before video watching(p=0.004). Conclusion : The med-add center-near MFCLs enhance accommodative function that could be effective to alleviated accommodative burden for the young adults with accommodative infacility.

Application of neural networks to the analysis of consumer opinions

This paper presents an analysis of the possibilities of using neural networks to classify text data in the form of comments. Moreover, results of research of two neural network optimization methods: Adam and Gradient are presented. The aim of the work is to conduct research on the behavior of the neural network depending on the change of parameters and the amount of data used to teach the neural network. To achieve the goal, a test application was created. It uses a neural network to display the overall assessment of the accommodation facility based on the added user feedback.

The effect of base‐in prism on vision‐related symptoms and clinical characteristics of young adults with convergence insufficiency; a placebo‐controlled randomised clinical trial

The aim of the present study was to evaluate the effect of base-in prism on symptoms and clinical characteristics of young adults with convergence insufficiency. In this randomised clinical trial, 64 CI patients aged 18-38years who presented to Bina Eye Hospital, Tehran, Iran between November 2018 and April 2019 were selected and randomly assigned to either prism or placebo groups. All participants underwent complete optometric examinations, including the measurement of visual acuity, objective and subjective refraction, and complete accommodative and binocular vision examinations. Clinical examinations were repeated after three months. The overall score of the Convergence Insufficiency Symptom Survey (CISS) was considered as the primary outcome measure. Secondary outcome measures included near exophoria, positive fusional vergence at near, near point of convergence, vergence facility, monocular accommodative facility, accommodative response, negative relative accommodation and accommodative convergence/accommodation (AC/A) ratio. The mean (S.D.) age of the participants was 25.5 (5.5) years and 44% of them were male. The mean CISS score was significantly lower in the prism group compared to the placebo group in the outcome examination (p<0.001). Moreover, the values of monocular accommodative facility, accommodative response, and negative relative accommodation were significantly higher in the prism group versus the placebo group (p<0.001). There was no significant difference in other parameters, including near positive fusional vergence, near point of convergence, vergence facility, and AC/A ratio between the two groups in the outcome examination (p>0.10). The base-in prism reduced symptoms in young adults with convergence insufficiency, while it had no significant effect on the near point of convergence, near positive fusional vergence, vergence facility and AC/A ratio. However, the results of this study only supports the symptomatic effectiveness of prism in the short term and further studies are needed to assess the long-term effect of prism.

Biosecurity risks posed by a large sea-going passenger vessel: challenges of terrestrial arthropod species detection and eradication

Large sea-going passenger vessels can pose a high biosecurity risk. The risk posed by marine species is well documented, but rarely the risk posed by terrestrial arthropods. We conducted the longest running, most extensive monitoring program of terrestrial arthropods undertaken on board a passenger vessel. Surveillance was conducted over a 19-month period on a large passenger (cruise) vessel that originated in the Baltic Sea (Estonia). The vessel was used as an accommodation facility to house workers at Barrow Island (Australia) for 15 months, during which 73,061 terrestrial arthropods (222 species - four non-indigenous (NIS) to Australia) were collected and identified on board. Detection of Tribolium destructor Uytt., a high-risk NIS to Australia, triggered an eradication effort on the vessel. This effort totalled more than 13,700 human hours and included strict biosecurity protocols to ensure that this and other non-indigenous species (NIS) were not spread from the vessel to Barrow Island or mainland Australia. Our data demonstrate that despite the difficulties of biosecurity on large vessels, stringent protocols can stop NIS spreading from vessels, even where vessel-wide eradication is not possible. We highlight the difficulties associated with detecting and eradicating NIS on large vessels and provide the first detailed list of species that inhabit a vessel of this kind.

Effect of vision therapy on measures of oculomotor function of patients presenting with post-concussion syndrome

Oculomotor dysfunction is a common symptom of post-concussion syndrome (PCS). By use of a retrospective analysis approach, the efficacy of Vision Therapy (VT) for the treatment of PCS related symptoms of the visual system was investigated. Overall, 56 patients were selected for inclusion in this study, all of which presented with clinical impairment of at least one measure of oculomotor functioning. Activities related to VT were wide-ranging and case-dependent, but all aimed to improve one of the five main areas of visual function. Following completion of VT, all patients demonstrated statistically or clinically significant improvements, as defined by use of Morgan’s Norms, in at least one measure of oculomotor functioning related to PCS. In general, improvements in measures of oculomotor functioning were greatest for near point of convergence, vergence facility and accommodative facility. Patients receiving 20 sessions of VT had improved and less variable outcomes when compared to those receiving 5-10 sessions of VT. In addition, VT was found to improve symptoms of visual discomfort in patients presenting with PCS. Results of this retrospective analysis demonstrate significant improvements in measured outcomes for all patients receiving VT and support VT as a treatment option for symptoms of PCS.