Convergence Insufficiency


Alvarez TL, Vicci VR, Alkan Y, et al. "  Vision therapy in adults with convergence insufficiency: clinical and functional magnetic resonance imaging measures."  Optom. Vis Sci. 2010 Nov 4.  
    Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, New Jersey (TLA, YA, HK, SG), Department of Vision Rehabilitation, Kessler Institute for Rehabilitation, West Orange, New Jersey (VRV), Private Practice, Westfield, New Jersey (VRV), Department of Radiology, University of Medicine and Dentistry of New Jersey, Newark, New Jersey (SG, BBB), and the Stroke Research Laboratory (AMB) and the Neuropsychology and Neuroscience Laboratory (NC), Kessler Foundation, West Orange, New Jersey.
   Purpose: This research quantified clinical measurements and functional neural changes associated with vision therapy in subjects with convergence insufficiency (CI).

   Methods: Convergence and divergence 4° step responses were compared between 13 control adult subjects with normal binocular vision and four CI adult subjects. All CI subjects participated in 18 h of vision therapy. Clinical parameters quantified throughout the therapy included: nearpoint of convergence, recovery point of convergence, positive fusional vergence at near, near dissociated phoria, and eye movements that were quantified using peak velocity. Neural correlates of the CI subjects were quantified with functional magnetic resonance imaging scans comparing random vs. predictable vergence movements using a block design before and after vision therapy. Images were quantified by measuring the spatial extent of activation and the average correlation within five regions of interests (ROI). The ROIs were the dorsolateral prefrontal cortex, a portion of the frontal lobe, part of the parietal lobe, the cerebellum, and the brain stem. All measurements were repeated 4 months to 1 year post-therapy in three of the CI subjects.

   Results: Convergence average peak velocities to step stimuli were significantly slower (p = 0.016) in CI subjects compared with controls; however, significant differences in average peak velocities were not observed for divergence step responses (p = 0.30). The investigation of CI subjects participating in vision therapy showed that the nearpoint of convergence, recovery point of convergence, and near dissociated phoria significantly decreased. Furthermore, the positive fusional vergence, average peak velocity from 4° convergence steps, and the amount of functional activity within the frontal areas, cerebellum, and brain stem significantly increased. Several clinical and cortical parameters were significantly correlated.

   Conclusions: Convergence peak velocity was significantly slower in CI subjects compared with controls, which may result in asthenopic complaints reported by the CI subjects. Vision therapy was associated with and may have evoked clinical and cortical activity changes.

  

Aziz S, Cleary M, Stewart HK, Weir CR "Are orthoptic exercises an effective treatment for convergence and fusion deficiencies?"  Strabismus.  Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, UK. 14(4):183-9: 2006.

    Purpose: To investigate whether orthoptic exercises are an effective way to influence the near point of convergence, fusion range and asthenopic symptoms.

    Methods: Seventy-eight patients met the inclusion criteria of visual acuity 6/9 or better, no history of orthoptic treatment, squint surgery or Meares Irlen syndrome/dyslexia. Information was collected from case records related to diagnosis, near point of convergence, fusion range, prism and cover test measurements and symptoms. Type, duration and frequency of exercises were also recorded. Non-parametric statistics were applied.
   Results: Patients ranged in age from 5 to 73 years (mean 11.9). Females outnumbered males (46:32). The diagnoses were: decompensating heterophoria (n = 50) or convergence insufficiency (n = 28: primary 27; secondary 1). Exophoria was more common (n = 65), than esophoria (n = 11) or orthophoria (n = 1). Treatments were aimed at improving near point of convergence and/or reduced fusional reserves. The mean treatment period was 8.2 months. Reduced near point of convergence normalized following treatment in 47/55 cases, and mean near point of convergenc e improved from 16.6 to 8.4 cm (p = 0.0001). Fusional reserves normalized in 29/50. Fusional convergence improved significantly for those with exodeviation (p > 0.0006). Asthenopic symptoms improved in 65 patients. A reduction in deviation of 5 pd or more occurred in 20 patients.

     Conclusions: Orthoptic exercises are an effective means of reducing symptoms in patients with convergence insufficiency and decompensating exophoria, and appear to target the proximal and fusional components of convergence. Their role in esophoria is unclear and needs further study.

 
Birnbaum MH, Cohen AH. "Efficacy of vision therapy for convergence insufficiency in an adult male population."  J Am Optom Assoc, 70 (4): 225-32, 1999.
    Background: Although vision therapy has reportedly been very successful in elimination of asthenopic symptoms in adults with convergence insufficiency, controlled studies have not been performed, and a clinical bias exists against prescribing vision therapy for adults with convergence insufficiency.   
    Methods: Sixty adult males over the age of 40 years (median age, 65 years) with convergence insufficiency were divided into three treatment groups: office-based vision therapy with supplementary home therapy, home therapy only, and a control group.
    Results: Vision therapy was successful in 61.9% of patients who received in-office plus home therapy, in 30% of patients who received home therapy only, and in 10.5% of the control group.  The success rate for patients who received active in-office vision therapy supplemented with home procedures was significantly greater than that for controls. Home therapy alone was less successful than in-office therapy. The success rate obtained with home therapy alone was not significantly greater than that demonstrated by controls.
    Conclusions: Vision therapy is effective in eliminating asthenopia and improving convergence function in adult patients. In-office therapy combined with home therapy tends to produce better results than does home therapy alone.

Borsting E., Rouse MW,  Chu R. "Measuring ADHD behaviors in children with symptomatic accommodative dysfunction or convergence insufficiency: a preliminary study"  Optometry 76: 588-92, 2006.
    Background:  Accommodative dysfunction and convergence insufficiency (CI) are common pediatric vision problems that have been associated with an increase in frequency and severity of vision-specific symptoms that affect children when doing schoolwork. However, the relationship between accommodative dysfunction and CI and other learning problems, such as attention deficit hyperactivity disorder (ADHD), are not well understood. The purpose of this study was to evaluate the frequency of ADHD behaviors in school-aged children with symptomatic accommodative dysfunction or CI.
     Methods:  Children 8 to 15 years of age with symptomatic accommodative dysfunction or CI were recruited from the teaching clinic at the Southern California College of Optometry. Children with learning disabilities or ADHD were excluded. One parent of each child completed the Conners Parent Rating Scale-Revised Short Form (CPRS-R:S). The childrens scores on the CPRS-R:S were compared with the normative sample.
     Results:  Twenty-four children (9 boys and 15 girls) participated in the study with a mean age of 10.93 years (SD = 1.75). On the CPRS-R:S, cognitive problem/inattention, hyperactivity, and ADHD index were significantly different from normative values (p d .001 for all tests).
     Conclusions:  The results from this preliminary study suggest that school-aged children with symptomatic accommodative dysfunction or CI have a higher frequency of behaviors related to school performance and attention as measured by the CPRS-R:S.

 

Borsting E; Rouse MW; De Land PN, "Prospective comparison of convergence insufficiency and normal binocular children on CIRS symptom surveys. Convergence Insufficiency and Reading Study (CIRS) group." Optom Vis Sci. 76(4):221-8, 1999.  
    Purpose: To test the validity-related evidence of a child and a parent symptom survey developed by the Convergence Insufficiency and Reading Study (CIRS) group.
    Methods: A case comparison method was used to measure differences in symptoms between 14 school-aged children (ages 8 to 13 years) with Convergence Insufficiency (CI) and 14 children with normal binocular vision (NBV).
    Results: A pooled t-test indicated that CI children and their parents scored higher than the NBV children and their parents on the child's survey (p<0.001) and parent's survey (p<0.001), respectively. CI children also scored significantly higher (p<0.03) on the Conners' Rating Scale for Parents.
    Conclusions: The results suggest that the CIRS symptom survey is a valid instrument for differentiating CI children from those with normal binocular vision.  Additionally, children in this age group were able to respond to a broad range of symptom questions associated with CI.


Cohen AH, Soden R "Effectiveness of visual therapy for convergence insufficiencies for an adult population." J Am Optom Assoc, (55): 491-4, 1984.
    Abstract: Optometric visual therapy is an effective treatment modality for convergence anomalies in both the adult and the geriatric populations. Complaints of blurred vision, diplopia, headaches, and asthenopia associated with convergence insufficiencies can be alleviated for most patients regardless of age.  Once the basic reflexes of convergence are established there seems to be a high level of long-term success.

 

Cooper J, Duckman R "Convergence insufficiency: incidence, diagnosis and treatment." J Amer O ptom Assoc, (49): 673-680, 1978.
    Abstract: Convergence insufficiency is one of the most common ocular problems. The paper carefully reviews the existing literature relating to etiology, diagnosis, sensory finding, treatment, and treatment results. In 17 studies involving 2149 patients, 78% were "cured" of convergence insufficiency by optometric vision therapy and an additional 15% were "improved."  Vision therapy for convergence insufficiency has been shown to be effective in reducing symptoms and improving vergence abilities.

Cooper J, Selenow A, et al. "Reduction of asthenopia in patients with convergence insufficiency after fusional vergence training."  Am J Optom Physiol Opt, 60:982-9, 1983.
    Abstract: Seven patients with convergence insufficiency and related asthenopia underwent automate fusional convergence training.  A matched-subjects control group crossover design was used to reduce placebo effects. All patients showed significant increases in vergence ranges with concurrent marked reduction of symptoms after training. All patients showed a flattening of and a increase in the base-out portion of their fixation disparity curve. Results demonstrated the effectiveness of fusional vergence training in reducing asthenopia in these patients. Subsequent accommodation and vergence training using traditional orthoptic procedures yielded further reduction of asthenopia, as well as an increase I the base-out fusional range.

 Cooper J. "Review of computerized orthoptics with specific regard to convergence insufficiency." Am J Optom Physiol Opt, 65:448-54, 1988.
    Abstract: Traditional vision training or orthoptics has used line or contour targets to eliminate suppression and improve vergence performance.  Manipulation of these stimuli is slow and arduous.  Line stimuli require an experienced doctor/technician to interpret responses.  Recently, automated vision training using microprocessor anaglyph stimuli, i.e., random dot stereograms (RDS), has been used in an operant conditioning paradigm.  This technique had improved motivation of the patient, improved reliability, and provided standardization of therapy.  In addition, the utilization of RDS associated with operant conditioning has been shown to improve vergence performance and to reduce asthenopia in the convergence insufficiency patient.

Daum KM. "Convergence insufficiency." Am J Optom Physiol Opt, 61:16-22, 1984.
    Abstract: A retrospective study of 110 subjects with convergence insufficiency was completed. Their mean age was 19.9 years. There were 72 females and 38 males in the group. The clinical profiles of these subjects were examined before and after a standard orthoptic treatment regimen. Over the course of treatment, the near angle of deviation, the AC/A ratio, a portion of the negative vergence values, the nearpoint of convergence, and the amplitude of accommodation were found to have changed in a statistically significant manner.

Granet DB, Gomi CF, Ventura R, Miller-Scholte A. "The Relationship between Convergence Insufficiency and ADHD." Strabismus. 13(4):163-8, 2005.
    Background: Children being evaluated for attention deficit hyperactivity disorder (ADHD) often have an eye exam as part of their evaluation. The symptoms of convergence insufficiency (CI) can make it difficult for a student to concentrate on extended reading and overlap with those of ADHD.
    Methods: A retrospective review of 266 patients with CI presenting to an academic pediatric ophthalmology practice was performed. All patients included were diagnosed with CI by one author (DBG) and evaluated for the diagnosis of ADHD. A computerized review was also performed looking at the converse incidence of CI in patients carrying the diagnosis of ADHD.
    Results: We reviewed 266 charts of patients with CI. Twenty-six patients (9.8%) were diagnosed with ADHD at some time in their clinical course. Of the patients with ADHD and CI, 20 (76.9%) were on medication for ADHD at the time of diagnosis for CI while 6 (23.1%) were either not on medication or the medication was discontinued several months before the diagnosis of CI. The review of computer records showed a 15.9% incidence of CI in the ADHD population.
    Conclusion: We report an apparent three-fold greater incidence of ADHD among patients with CI when compared with the incidence of ADHD in the general US population (1.8-3.3%) (Leslie et al., 2004). We also note a seeming three-fold greater incidence of CI in the ADHD population. This may simply represent an association and not be a causative relationship. Until further studies are performed, however, patients diagnosed with ADHD should be evaluated to identify the small subset that may have CI - a condition that responds well to treatment at home.

Grisham JD. "Visual therapy results for convergence insufficiency: A literature review." Am J Optom & Physiol Optics, 65 (6): 448-454, 1988.
    This paper is a review of the literature relative to treatment results for convergence insufficiency utilizing vision therapy training procedures. Vision therapy is known to improve the nearpoint of convergence and fusional convergence and to ameliorate associated symptoms. The overall cure rate is 72%. Furthermore, the training results appear to persist for at least 2 years if the patients are initially cured and are independent of age until the late presbyopic years. Also, recent studies indicate the type of training procedures which yield the most effective training results.

Jenkins RH. "Characteristics and Diagnosis of Convergence Insufficiency." American Orthoptic Journal, 49:7-11, 1999.
     Convergence Insufficiency is defined as the inability to obtain and/or maintain adequate binocular convergence without undue effort. It is one of the most common causes of ocular discomfort, the most common cause of muscular asthenopia and affects 3-5% of the population. The diagnosis is made by the presence of asthenopic symptoms and reduced amplitudes of convergence. The near point of convergence may not be reduced. The etiology of convergence insufficiency is usually idiopathic but several causes are reviewed in this article. The importance of a detailed history to assess the type of convergence insufficiency present and possible causes is noted. The important parts of the ophthalmologic examination are reviewed including near point of accommodation and convergence and the measurement of fusional amplitudes.

Mazow ML, France TD, et al. "Acute accommodative and convergence insufficiency."  Tr Am Opthmalmol Soc, 87:158-68, 1989.
    Abstract: The facility of accommodation and convergence allows persons to read at close range.  When these mechanisms fail, reading becomes tiring, frequently producing headaches and even diplopia. This study reviewed the treatment of 26 young patients with asthenopic symptoms who had a combination of profoundly decreased accommodation and convergence in the absence of any other neurologic symptoms or signs.  Twenty-two of 26 (84.6%) patients were treated with orthoptic exercises to improve convergence.  Twenty-one of 26 (81%) were given plus lenses to aid in accommodation.  Patients were seen for mean of 13.3 visits over an average of 11.8 months.  Seventeen of 26 patients (65.3%) showed definite improvement after treatment and were completely asymptomatic.  Seven of 26 patients (26.9%) reported some improvement of symptoms. Two of 26 patients (7.6%) reported no improvement of symptoms.  However, both of these patients had been treated for less than 2 months. Of the 24 patients whom experienced improvement in symptoms, their headaches decreased and their school performance improved dramatically.

Passmore JW, Maclean F. "Convergence insufficiency and its management." Am J Ophthal, 43: 448-56, 1957.
     This study reported on the evaluation of 100 patients receiving a course of orthoptics for the treatment of convergence insufficiency. The average patient age was 24, range of 8 to 42 years of age. Orthoptic treatment averaged seven sessions of 30 minutes each. A total of 82 patients received complete relief of subjective symptoms at the end of treatment and 18 received partial relief.

 Petrunak JL. "The treatment of convergence insufficiency." American Orthoptic Journal, 49:12-16, 1999.
     Idiopathic convergence insufficiency is characterized by inadequate fusional convergence, causing a variety of asthenopic symptoms which occur during the act of reading.  Orthoptic therapy to increase fusional convergence amplitudes and enhance voluntary convergence is the primary treatment of convergence insufficiency. When unresponsive to orthoptic therapy, other treatment options include optical correction with base-in prisms or surgical intervention in cases associated with a near exophoria. Convergence-accommodative insufficiency and subnormal convergence associated with head trauma are entities that are symptomatically similar to classic convergence insufficiency, but do not demonstrate the same response to orthoptic therapy.

 

Rouse MW, Borsting E, Hyman L, Hussein M, Cotter SA, Flynn M, Scheiman M, Gallaway M, De Land PN, "Frequency of Convergence Insufficiency Among Fifth and Sixth Graders." The Convergence Insufficiency and Reading Study (CIRS) group. Optom Vis Sci. 76(9):643-9, 1999.
     Purpose: To estimate the frequency of convergence insufficiency (CI) and its related clinical characteristics among 9- to 13-year-old children.
     Methods: Fifth and sixth graders were screened in school settings at three different study sites. Eligible children with 20/30 or better visual acuity, minimal refractive error, no strabismus, and exophoria at near were evaluated according to a standardized protocol to determine the presence and severity of CI. These children were classified according to the presence and number of the following clinical signs: (1) exophoria at near > or =4delta than far, (2) insufficient fusional convergence, and (3) receded nearpoint of convergence. Also, children were classified as accommodative insufficient (AI) if they failed Hofstetter's minimum amplitude formula or had greater than a + 1.00 D lag on Monocular Estimate Method retinoscopy.
     Results: Of 684 children screened, 468 (68%) were eligible for further evaluation. Of these, 453 had complete data on CI measurements and were classified as: no CI (nonexophoric at near or exophoric at near and < 4delta difference between near and far) (78.6%); low suspect CI (exophoric at near and one clinical sign: exophoria at near > or =4delta than far) (8.4%); high suspect CI (exophoric at near and two clinical signs) (8.8%); and definite CI (exophoric at near and three clinical signs) (4.2%). CI status varied according to ethnicity and study site (p < 0.0005), but not gender. The frequency of AI increased with the number of CI-related signs. For CI children with three signs, 78.9% were classified as also having AI. 
     Conclusions: These findings suggest that CI (defined as high suspect and definite) is frequent (13%) among fifth and sixth grade children. In addition, there is a high percentage of CI children with an associated AI.

 

Rouse MW, Hyman L, Hussein M, Solan H. "Frequency of convergence insufficiency in optometry clinic settings. Convergence Insufficiency and Reading Study (CIRS) Group." Optom Vis Sci 1998 Feb;75(2):88-96
     Purpose: To estimate the frequency of convergence insufficiency (Cl) and its related characteristics among 8- to 12-year-old children randomly selected from 2 optometry clinic populations.
     Methods: Clinic records of 620 children were randomly selected and reviewed according to a standard protocol, using a systematic sampling method based on the total number of 8- to 12-year-old children seen over a 1-year period at 2 optometry clinics. Records were reviewed for demographic and clinical data. Data on Cl-related symptoms were obtained at one of the sites. Records that met the eligibility criteria of: good visual acuity (20/30 or better in both eyes); minimal refractive error (-0.50 to +1.00 D and < or = 1.00 D of astigmatism in either eye, and < or = 1.00 D of anisometropia); and no strabismus were evaluated for Cl-related characteristics. Eligible children were classified according to the direction of their near heterophoria and the number of the following clinical signs present: (1) exophoria at near > or = 4 delta than at far; (2) insufficient fusional convergence [i.e., failing Sheard's criterion or minimum normative positive fusional vergence (PFV) of 12 delta base-out (BO) blur/15 delta BO break]; and (3) receded nearpoint of convergence (NPC) of > or = 7.5 cm break or > or = 10.5 cm recovery. Children were then classified as: no Cl (nonexophoric at near or < 4 delta difference between far and near); low suspect (exophoric at near and1 sign); high suspect (exophoric at near and 2 signs); or definite Cl (exophoric at near and 3 signs).
     Results: Sixty-seven percent (415/620) of the records met the eligibility criteria and had complete data on phoria, NPC, and PFV. The age (mean +/- SD) of the study population was 10.2 +/- 1.2 years. Ethnicity data were available for 85% of those eligible; the ethnic distribution was 36% African American, 29% Caucasian, 19% Hispanic, and 1% Asian. About one-half of the 415 children were classified as either low suspect (33%); high suspect (12%); or definite Cl (6%). Clinically significant Cl (high suspect and definite categories) was identified in 17.6% of the children. The percentage of children rated as symptomatic increased with the number of Cl-related clinical signs present.
     Conclusions: These findings suggest a high frequency of Cl in optometry clinic populations and a potential correlation between patient symptoms and the number of Cl signs present.

 

Rouse M, Borsting E, Mitchell GL, Kulp MT, Scheiman M, Amster D, Coulter R, Fecho G, Gallaway M; The CITT Study Group. "Academic Behaviors in children with convergence insufficiency with and without parent-reported ADHD." Optom Vis. Sci. 2009.
*OD, MS, FAAO daggerMPH, FAAO double daggerOD, FAAO section signOD Southern California College of Optometry, Fullerton, California (MR, EB), The Ohio State University College of Optometry, Columbus, Ohio (GLM, MTK), Salus University, College of Optometry, Philadelphia, Pennsylvania (MS, MG), and NOVA Southeastern University, Ft. Lauderdale, Florida (DA, RC, GF). The CITT Study Group members are listed in the Acknowledgments.
     Purpose: To determine if children with symptomatic Convergence Insufficiency without the presence of parent-reported Attention Deficit Hyperactivity Disorder (ADHD) have higher scores on the academic behavior survey (ABS).
     Methods: The ABS is a 6-item survey that evaluates parent concern about school performance and the parents' perceptions of the frequency of problem behaviors that their child may exhibit when reading or performing schoolwork (such as difficulty completing work, avoidance, and inattention). Each item is scored on an ordinal scale from 0 (Never) to 4 (Always) with a total score ranging from 0 to 24. The survey was administered to the parents of 212 children 9- to 17-year old (mean age 11.8 years.) with symptomatic convergence insufficiency before enrolling into the Convergence Insufficiency Treatment Trial and to 49 children with normal binocular vision (NBV) (mean age 12.5 years). The parents reported whether the child had ADHD, and this information was used to divide the symptomatic convergence insufficiency group into the convergence insufficiency with parent report of ADHD or convergence insufficiency with parent report of no ADHD groups.
     Results: Sixteen percent of the convergence insufficiency group and 6% of the NBV group were classified as ADHD by parental report. An analysis of covariance showed that the total ABS score for the symptomatic convergence insufficiency with parent report of ADHD group (15.6) was significantly higher than the symptomatic convergence insufficiency with parent report of no ADHD group (11.7, p = 0.001) and the NBV group (8.7, p < 0.0001). Children with convergence insufficiency with parent report of no ADHD scored significantly higher on the ABS than the NBV group (p = 0.036).
     Conclusions: Children with symptomatic convergence insufficiency with parent report of no ADHD scored higher on the ABS, when compared to children with NBV. Children with parent report of ADHD or related learning problems may benefit from comprehensive vision evaluation to assess for the presence of convergence insufficiency.

Scheiman, M; Cotter, S; Rouse, M; Mitchell, G L; Kulp, M; Cooper, J; Borsting, E; and the Convergence Insufficiency Treatment Trial (CITT) Study Group "Randomised clinical trial of treatments for convergence insufficiency in children." Arch. Opthalmol. 2005.
  Purpose: To compare base-in prism reading glasses with placebo reading glasses for the treatment of symptomatic convergence insufficiency (CI) in children aged 9 to <18 years. 
   Methods: In a randomised clinical trial, 72 children aged 9 to <18 years with symptomatic CI were assigned to either base-in prism glasses or placebo reading glasses. Symptom level, measured with a quantitative symptom questionnaire (CI Symptom Survey-V15), was the primary outcome measure. Near point of convergence and positive fusional vergence at near were secondary outcomes. 
   Results: The mean (SD) CI Symptom Survey score decreased (that is, less symptomatic) in both groups (base-in prism glasses from 31.6 (10.4) to 16.5 (9.2); placebo glasses from 28.4 (8.8) to 17.5 (12.3)). The change in the CI Symptom Survey scores (p = 0.33), near point of convergence (p = 0.91), and positive fusional vergence (p = 0.59) were not significantly different between the two groups after 6 weeks of wearing glasses. 
   Conclusions: Base-in prism reading glasses were found to be no more effective in alleviating symptoms, improving the near point of convergence, or improving positive fusional vergence at near than placebo reading glasses for the treatment of children aged 9 to <18 years with symptomatic CI.

 

Scheiman, M; Cotter, S; Rouse, M; Mitchell, G L; Kulp, M; Cooper, J; Borsting, E; et al (CITT).  "A Randomized Clinical Trial of Vision Therapy/Orthoptics versus Pencil Pushups for the Treatment of Convergence Insufficiency in Young Adults."  Optometry and Vision Science. 2005.
   Purpose: The purpose of this article is to compare vision therapy/orthoptics, pencil pushups, and placebo vision therapy/orthoptics as treatments for symptomatic convergence insufficiency in adults 19 to 30 years of age.
   Methods: In a randomized, multicenter clinical trial, 46 adults 19 to 30 years of age with symptomatic convergence insufficiency were randomly assigned to receive 12 weeks of office-based vision therapy/orthoptics, office-based placebo vision therapy/orthoptics, or home-based pencil pushups. The primary outcome measure was the symptom score on the Convergence Insufficiency Symptom Survey. Secondary outcome measures were the near point of convergence and positive fusional vergence at near.
   Results: Only patients in the vision therapy/orthoptics group demonstrated statistically and clinically significant changes in the near point of convergence (12.8 cm to 5.3 cm, p = 0.002) and positive fusional vergence at near (11.3” to 29.7”, p = 0.001). Patients in all three treatment arms demonstrated statistically significant improvement in symptoms with 42% in office-based vision therapy/orthoptics, 31% in office-based placebo vision therapy/orthoptics, and 20% in home-based pencil pushups achieving a score <21 (our predetermined criteria for elimination of symptoms) at the 12-week visit.
   Discussion: In this study, vision therapy/orthoptics was the only treatment that produced clinically significant improvements in the near point of convergence and positive fusional vergence. However, over half of the patients in this group (58%) were still symptomatic at the end of treatment, although their symptoms were significantly reduced. All three groups demonstrated statistically significant changes in symptoms with 42% in office-based vision therapy/orthoptics, 31% in office-based placebo vision therapy/orthoptics, and 20% in home-based pencil push-ups meeting our criteria for elimination of symptoms.

Scheiman, M; Kulp, M; Cotter, S; Mitchell, G L; Rouse, M; et al (CITT).  "Long-term effectiveness of treatments for symptomatic convergence insufficiency in children."  Optom Vis Sci. Sep;86(9):1096-103, 2009. 
   Purpose: To assess the long-term stability of improvements in symptoms and signs in 9- to 17-year-old children enrolled in the Convergence Insufficiency Treatment Trial who were asymptomatic after treatment for convergence insufficiency.

   Methods: Seventy-nine patients who were asymptomatic after a 12-week therapy program for convergence insufficiency were followed for 1 year [33/60 in office-based vergence/accommodative therapy (OBVAT), 18/54 in home-based pencil push-ups (HBPP), 12/57 in home-based computer vergence/accommodative therapy and pencil push-ups (HBCVAT+), and 16/54 in office-based placebo therapy (OBPT)]. Symptoms and clinical signs were measured 6 months and 1 year after completion of the 12-week therapy program. The primary outcome measure was the mean change on the Convergence Insufficiency Symptom Survey (CISS). Secondary outcome measures were near point of convergence, positive fusional vergence at near, and proportions of patients who remained asymptomatic or who were classified as successful or improved based on a composite measure of CISS, near point of convergence, and positive fusional vergence. 
   Results: One-year follow-up visit completion rate was 89% with no significant differences between groups (p = 0.26). There were no significant changes in the CISS in any treatment group during the 1-year follow-up. The percentage who remained asymptomatic in each group was 84.4% (27/32) for OBVAT, 66.7% (10/15) for HBPP, 80% (8/10) for HBCVAT+, and 76.9% (10/13) for OBPT. The percentage who remained either successful or improved 1-year posttreatment was 87.5% (28/32) for OBVAT, 66.6% (10/15) for HBPP, 80% (8/10) for HBCVAT+, and 69.3% (9/13) for OBPT.

   Conclusions: Most children aged 9 to 17 years who were asymptomatic after a 12-week treatment program of OBVAT for convergence insufficiency maintained their improvements in symptoms and signs for at least 1 year after discontinuing treatment. Although the sample sizes for the home-based and placebo groups were small, our data suggest that a similar outcome can be expected for children who were asymptomatic after treatment with HBPP or HBCVAT+.

Scheiman M; Mitchell GL; Cotter S; Kulp M; et al (CITT).  "The convergence insufficiency treatment trial: design, methods, and baseline data."  Ophthalmic Epidemiol. Jan-Feb;15(1): 2008.  
   Objective: This report describes the design and methodology of the Convergence Insufficiency Treatment Trial (CITT), the first large-scale, placebo-controlled, randomized clinical trial evaluating treatments for convergence insufficiency (CI) in children. We also report the clinical and demographic characteristics of patients. 
   Methods: We prospectively randomized children 9 to 17 years of age to one of four treatment groups: 1) home-based pencil push-ups, 2) home-based computer vergence/accommodative therapy and pencil push-ups, 3) office-based vergence/accommodative therapy with home reinforcement, 4) office-based placebo therapy. Outcome data on the Convergence Insufficiency Symptom Survey (CISS) score (primary outcome), near point of convergence (NPC), and positive fusional vergence were collected after 12 weeks of active treatment and again at 6 and 12 months posttreatment. 
   Results: The CITT enrolled 221 children with symptomatic CI with a mean age of 12.0 years (SD = +2.3). The clinical profile of the cohort at baseline was 9Delta exophoria at near (+/- 4.4) and 2Delta exophoria (+/-2.8) at distance, CISS score = 30 (+/-9.0), NPC = 14 cm (+/- 7.5), and near positive fusional vergence break = 13 Delta (+/- 4.6). There were no statistically significant nor clinically relevant differences between treatment groups with respect to baseline characteristics (p > 0.05). 
   Conclusion: Hallmark features of the study design include formal definitions of conditions and outcomes, standardized diagnostic and treatment protocols, a placebo treatment arm, masked outcome examinations, and the CISS score outcome measure. The baseline data reported herein define the clinical profile of those enrolled into the CITT.

 

 Scheiman M; Mitchell GL; Cotter S; Kulp M; et al (CITT).  "Vision therapy/orthoptics for symptomatic convergence insufficiency in children: treatment kinetics."  Optom. Vis. Sci. June 10: 2010.  
    Purpose: To evaluate the kinetics of change in symptoms and signs of convergence insufficiency (CI) during 12 weeks of treatment with commonly prescribed vision therapy/orthoptic treatment regimens.

    Methods: In a randomized clinical trial, 221 children aged 9 to 17 years with symptomatic CI were assigned to home-based pencil push-ups (HBPP), home-based computer vergence/accommodative therapy and pencil push-ups (HBCVAT+), office-based vergence/accommodative therapy with home reinforcement (OBVAT), or office-based placebo therapy with home reinforcement (OBPT). Symptoms and signs were measured after 4, 8, and 12 weeks of treatment. The outcome measures were the mean CI Symptom Survey (CISS), near point of convergence (NPC), positive fusional vergence (PFV), and proportions of patients who were classified as successful or improved based on a composite measure of CISS, NPC, and PFV.
    Results: Only the OBVAT group showed significant improvements in symptoms between each visit (p < 0.001). Between weeks 8 and 12, all groups showed a significant improvement in symptoms. Between-group differences were apparent by week 8 (p = 0.037) with the fewest symptoms in the OBVAT group. For each group, the greatest improvements in NPC and PFV were achieved during the first 4 weeks. Differences between groups became apparent by week 4 (p < 0.001), with the greatest improvements in NPC and PFV in the OBVAT group. Only the OBVAT group continued to show significant improvements in PFV at weeks 8 and 12. The percentage of patients classified as "successful" or "improved" based on our composite measure increased in all groups at each visit.
    Conclusions: The rate of improvement is more rapid for clinical signs (NPC and PFV) than for symptoms in children undergoing treatment for CI. OBVAT results in a more rapid improvement in symptoms, NPC and PFV, and a greater percentage of patients reaching pre-determined criteria of success when compared with HBPP, HBCVAT+, or OBPT.

Scheiman M, Rouse M, Kulp MT, Cotter S, Hertle R, Mitchell GL"Treatment of convergence insufficiency in childhood: a current perspective."   Optom Vis Sci, 2009 May;86(5):420-8. 
   PURPOSE: To provide a current perspective on the management of convergence insufficiency (CI) in children by summarizing the findings and discussing the clinical implications from three recent randomized clinical trials in which we evaluated various treatments for children with symptomatic CI. We then present an evidence-based treatment approach for symptomatic CI based on the results of these trials. Finally, we discuss unanswered questions and suggest directions for future research in this area.
   METHODS: We reviewed three multi-center randomized clinical trials comparing treatments for symptomatic (CI) in children 9 to 17 years old (one study 9 to 18 years old). Two trials evaluated active therapies for CI. These trials compared the effectiveness of office-based vergence/accommodative therapy, office-based placebo therapy, and home-based therapy [pencil push-ups alone (both trials), home-based computer vergence/accommodative therapy, and pencil push-ups (large-scale study)]. One trial compared the effectiveness of base-in prism reading glasses to placebo reading glasses. All studies included well-defined criteria for the diagnosis of CI, a placebo group, and masked examiners. The primary outcome measure was the Convergence Insufficiency Symptom Survey score. Secondary outcomes were near point of convergence and positive fusional vergence at near. 
   RESULTS: Office-based vergence/accommodative therapy was significantly more effective than home-based or placebo therapies. Base-in prism reading glasses were no more effective than placebo reading glasses for the treatment of symptomatic CI in children.
   CONCLUSIONS: Recent clinical trials showed that office-based vision therapy was successful in about 75% of patients (resulting in normal or significantly improved symptoms and signs) and was the only treatment studied which was more effective than placebo treatments for children with symptomatic CI. Eye care providers who do not currently offer this treatment may consider referring these patients to a doctor who provides this treatment or consider expanding the treatment options available within their practice to manage this condition.