- Email: [email protected]
Accommodative Esotropia Long Range Follow-up
Accommodative Esotropia Long Range Follow-up KENNETH C. SWAN, MD
Abstract: Thirty-nine adult patients treated for typical (refractive) accommodative esotropia in childhood continue to have problems because they have not outgrown their hypermetropia, and the majority have not developed stable binocular vision. Their hypermetropia became maximal (median 5.7 diopters) by age 6, decreased in adolescence, and then stabilized (median 4 diopters). Thirty-eight of the 39 adults wear correcting lenses full-time. Nearly all depend on relaxed accommodation to maintain alignment when they remove their glasses. Ten patients, all of whom received treatment before a constant esotropia developed are essentially orthophoric with glasses and have normal binocular vision. The remainder have small-angle deviations with glasses, 14 with varying degrees of amblyopia and peripheral fusion and 15 with anomalous correspondence and suppression. As adults, only one patient with normal binocular function has required surgery whereas 13 of the patients lacking normal fusion have had surgery for increasing esotropia, postoperative exotropia, or consecutive exotropia. [Key words: accommodative control training, accommodative esotropia, amblyopia, anomalous retinal correspondence, consecutive and postoperative exotropia, hypermetropia.] Ophthalmology 90: 1141-1145, 1983
Most reviews of accommodative esotropia have been concerned primarily with its management in childhood. There has been a need for additional documentation of its course on into adult life and of the ultimate results of treatment. For this reason I have reviewed the course and current status of 39 adults (23-46 years of age) who underwent treatment for accommodative esotropia early in childhood and have been re-examined by me at intervals for 20 or more years. Some have been patients at the Oregon Health Sciences University for nearly four decades and have reached middle-age.
PATIENT SELECTION This review includes only patients who acquired an esodeviation because uncorrected high hypermetropia caused excessive accommodative convergence. With correcting lenses their ratios of accommodative convergence From the Elks Children's Eye Clinic, Department of Ophthalmology, Oregon Health Sciences University, Portland, Oregon. Presented at the Eighty-seventh Annual Meeting of the American Academy. San FranCiSCO, California, October 30-November 5, 1982. Reprint requests to Ker:lneth C. Swan. MD, Oregon Health Sciences University, 3181 S.w. Sam Jackson Park Road, Portland, OR 97201.
0161-6420/83/1000/lJ41/$1.05 © American Academy of Ophthalmology
to accommodation and their amplitudes of accommodation were normal. In accordance with the recommendations of the 1956 American Academy's Symposium on Accommodative Esotropia these patients were classified as having typical (refractive) accommodative esotropia. 1 Excluded from the review were patients with atypical types of accommodative esotropia, that is, those due to an abnormal accommodative convergence to accommodation ratio or subnormal accommodative ability. Also excluded were patients with 2 diopters or more of anisometropia in childhood, vertical deviations, and morphologic abnormalities of either eye. The median age of the first manifestations of esotropia as determined by history and by review of family photographic albums was 26 months, with extremes of 8 months and 71f2 years. In the 71f2-year-old child the esotropia was precipitated by occlusion. Eighteen of the 39 patients had siblings or parents with esotropia. Among the 39 patients in the study were four pairs and one trio of siblings.
INITIAL EXAMINATIONS The median age of my first examination of these patients was 3112 years, with extremes of 8 months to 71f2 years. Most of the children already had developed a con1141
OPHTHALMOLOGY •
OCTOBER 1983 •
Table 1. Changes in Hypermetropia in Childhood
Age
2
3
4
6
8
No. of Patients
Diopters* Median
Range
3.75 4.37 4.75 5.7 5.6
2.5-5.5 3.5-7.37 3.5-8.75 3.62-9.25 3.5-9.5
7
22
37 38 39
* Expressed as spherical equivalents.
stant esotropia. The deviation without glasses was extremely variable but with distant fixation was generally in the 20 to 30 prism diopter range. This placed the blind spot of the deviating eye in correspondence with the point of fixation. Determination of refractive errors was made after multiple instillations of 1% atropine sulfate or 0.25% scopolamine hydrobromide to insure maximal cycloplegia. As shown in Table 1, the maximal median hypermetropia of 5.7 diopters was reached by age 6 years, a level about 1 diopter greater than found by Costenbader. 2 There was a high prevalence of sensory abnormalities. Twenty-four patients had amblyopia in the deviating eye (Table 2). Fifteen patients had anomalous retinal correspondence when tested with after-images, haploscopic devices, and anaglyphic glasses. 3 All had developed a constant esotropia before the age of 3 and with two exceptions had not received treatment before that age. Ten of the 15 patients with anomalous correspondence also had unilateral amblyopia.
METHODS OF TREATMENT In attempts to achieve the ideal goal of normal binocular vision without glasses I treated these patients in accordance with the principles outlined by Costenbader4 in 1956 and recently reaffirmed by Tongue. 5 The initial step was full correction of the hypermetropia. As these patients had normal ratios of accommodative convergence to accommodation and normal accommodative ability, bifocals seldom were required. Anticholin-
Table 2. Initial Visual Acuity in Amblyopic Eye of 24 Children with Typical Accommodative Esotropia 3/200 20/400 20/100-20/50 20/100-20/40 (under treatment)*
1
2 12
9
24 * Occlusion started in nine children too young for accurate acuity determination.
1142
VOLUME 90 •
NUMBER 10
esterase agents were prescribed for a few infants who would not wear glasses consistently. The next major step was management of that deviation which persisted after wearing of the full cycloplegic correction. There was a strong correlation between the amount of residual deviation and the duration of constant esotropia before effective glasses were prescribed. Nearly all of the 14 children with less than 5 prism diopters of residual deviation had had either an intermittent esotropia or a constant esotropia of only a few weeks duration. In contrast, most of the 28 patients who had a residual esotropia of more than 5 prism diopters in distant vision had had a constant esotropia for at least several months before treatment. The management of residual esotropia varied in accordance with the patient's potential for normal binocular single vision. For patients with fusional ability and a deviation of less than 10 prism diopters, base out prisms were incorporated in the glasses in the least strength necessary for binocular single vision. Surgery was undertaken to correct fully larger amounts of residual deviation. In those patients with an inconspicuous deviation and no potential for fusion, no surgery was undertaken and no prisms were prescribed. With noticeable deviation and poor fusional potential, the goal of surgery was to reduce the deviation to cosmetically acceptable levels of esotropia. To lessen the risk of a later exotropia, full correction of the esotropia was avoided. No operations were performed merely to reduce the need for the wearing of spectacles or for deviations that were present only in near vision. Operations primarily to correct residual esodeviation were performed on 20 of the 39 patients before the age of 15. Unilateral inferior oblique recessions were combined with horizontal muscle surgery in two of these patients. Exotropia developed in six patients following correction of their hypermetropia. One, a 4-year-old patient with an amblyopic eye shifted from esotropia to exotropia within a few weeks. Five additional patients gradually shifted from esotropia into exotropia over a period of years. Their median refractive error was over 6 diopters of hypermetropia, and all had amblyopia in one eye. The exotropia first became manifest in near vision and slowly worsened. Reductions in the hypermetropic spectacle corrections to stimulate accommodative convergence were prescribed, but all six patients with consecutive exotropia eventually required surgery. For the 24 patients with amblyopia, occlusion and exercises to stimulate the amblyopic eye were prescribed as soon as the effects of corrective lenses were established. Pleoptics were used in one patient with eccentric fixation and anomalous retinal correspondence. Other orthoptic training was prescribed to develop fusional vergences, especially relative fusional divergence. Antisuppression measures were used in those patients with normal retinal correspondence, but after multiple failures, orthoptic measures to correct anomalous correspondence were discontinued. All patients were trained to keep their accommodation relaxed and vision blurred when they removed their glasses.
SWAN
•
ACCOMMODATIVE ESOTROPIA
Table 4. Operations on 13 Adults Lacking Normal Fusion
COURSE IN ADULT LIFE CHANGES IN REFRACTIVE ERROR
Myopia increases and hypermetropia usually decreases during rapid bodily growth in the second decade of life. For this reason, parents of young children with accommodative esotropia sometimes are given the hope that their children will outgrow most of their hypermetropia, but that did not occur in this series. Their hypermetropia began to decrease by age 10 but, as shown in Table 3, it was still over 4 diopters at age 20 and changed little thereafter. Of the 39 patients, only two had less than 3 diopters of hypermetropia as adults! There were several patients with high (6-8.5 diopters) hypermetropia who had no change in their refractive error and one interesting group of four patients who had no significant change in their amblyopic eye but demonstrated a decrease of 3 or more diopters in the normal eye! INTERPUPILLARY DISTANCE
There is a second "growth factor" that has a favorable effect on accommodative esotropia. I Convergence requirements for near vision increase with widening of the interpupillary distance. The median interpupillary distance of these patients was only 51 mm at age 3 and therefore, their convergence requirement for their usual fixation distance of 26-28 cm was about 16 prism diopters. At age 16, the median interpupillary distance had widened to 64 mm and their convergence requirements had increased to about 22 prism diopters. 7 Lessened esodeviation or greater exodeviation in near vision occurred in nearly all of these patients commensurate with broadening of their facial structures. THE BASIC DEVIATION
The basic deviation, ie, fusion-free alignment, measured with the refractive error corrected and the patients fixating at a distant target was determined with the prism and alternate cover test in all patients. Subjective tests such as the Maddox rod also were made in the 24 patients with normal retinal correspondence. The basic deviation stabilized near orthophoria by the age of 20 in 9 of the Table 3. Changes in Hypermetropia with Age
Age
8 10 14 20 30 40
No. of Patients
Diopters* Median
Range
5.7 5.4 4.25 4.12 4.00 3.87
3.5-9.5 3.5-9.5 3.25-8.5 2.25-8.5 2.25-8.5 1.75-8.5
39 39 39 39 29
6
* Expressed in spherical equivalents.
Initial surgery for esotropia Additional surgery for esotropia Initial surgery for consecutive exo Initial surgery for postoperative exotropia Additional surgery for postoperative exotropia
2 5 3 1 2 13
10 patients with normal fusion but the tenth patient required surgery after her esodeviation gradually increased during her late 30s. Thirteen of the 29 patients lacking the stabilizing effect of fusion required initial or additional operations as adults (Table 4).
RESULTS OF TREATMENT None of the 39 adults have been disabled but all have had enough symptoms to seek re-examination at intervals, usually less than 2 years. Thirty-eight of the 39 are wearing glasses or contact lenses full-time. One 29-year-old patient with 2.25 diopters of hypermetropia in his nonamblyopic eye wears his glasses only for reading. He has a small angle exotropia. The functional status of the 39 adults is summarized in Table 5. Only ten have normal binocular vision, that is, bifoveal perception with stereopsis. There are 14 other patients with varying degrees of unilateral amblyopia and peripheral fusion. They have minimal or no horizontal deviation. None of the 15 patients with anomalous correspondence have regained normal correspondence although several received prolonged orthoptic training in childhood. As their deviations were eliminated or greatly reduced, their angles of anomaly simply became small and/or variable. Only 3 of the 24 patients with amblyopia have had no measureable improvement in their visual acuity. These three have perifoveal eccentric fixation and acuity of only 20/200 with single letters. Three patients had minimal improvement (from 20/200 to the range of 20/100-80). The results otherwise, were favorable in that 18 of the 24 patients now have corrected visual acuity of at least 20/40 in their amblyopic eye and of this group, 8 have corrected acuity of 20/25 or better. Of the three patients who have reached presbyopic age, two have new problems. A 46-year-old woman with 5.6 diopters of hypermetropia and an amblyopic (20/100) eye, has practically no accommodative convergence when Table 5. Functional Status of 39 Adults with Typical Accommodative Esotropia in Childhood Normal binocular single vision Peripheral fusion-minimal amblyopia and some fusional vergences Gross peripheral fusion-residual amblyopia (20/50-20/200) Abnormal retinal correspondence-suppression
10 6
8 15
1143
OPHTHALMOLOGY •
OCTOBER 1983 •
VOLUME 90 •
NUMBER 10
DISCUSSION
Fig 1. Accommodative control. A 14-year-old girl has normal binocular alignment (top) when her 5 diopters of hypermetropia is corrected. A right esotropia (middle) develops when she attempts to see clearly without glasses. Her eyes straighten (bottom) when she leaves her accommodation relaxed. The decrease in acuity does not interfere with activities like swimming which require removal of her glasses.
she looks through the reading addition and is developing a conspicuous exotropia in near vision. The second patient who has normal fusion also has diminished accommodative convergence. She requires 6 diopters base in prism for comfortable single vision with her reading glasses. 1144
Some patients with typical accommodative esotropia in childhood do not require treatment as adults because they wore correcting lenses early in life, developed normal binocular vision, and then lost most of their hypermetropia during adolescence; however, as this study documents, the problems of many patients with typical accommodative esotropia do not end with childhood because they do not outgrow their hypermetropia. Their problems are greater if, in addition, they do not develop stable binocular single vision. With a median hypermetropia of 4 diopters, even those patients who developed exodeviations have become increasingly dependent upon spectacles or contact lenses as their accommodative abilities have decreased. This is understandable because a 30-year-old patient with 4 diopters of uncorrected hypermetropia has the reading capability of an emmetropic individual at age 45! He still may be able to accommodate enough to see distant objects clearly but then stimulates accommodative convergence. In effect, the progressive decrease in accommodative ability in the third and fourth decades makes comfortale binocular single vision without glasses an unrealistic goal for those patients who retain significant amounts of hypermetropia. There were 29 patients in this series who did not receive correction of their high hypermetropia early enough to develop normal fusion. Their problems continuing into adult life document that the price of delaying treatment of accommodative esotropia in infancy is high indeed. Lacking normal fusional vergences, their binocular alignment in intermediate and near vision is determined primarily by the degree of accommodative effort. In addition to varying degrees of amblyopia and almost total dependence upon glasses for maintenance of alignment with clear vision, one third already have required surgery either for recurrences or progression of esotropia or for postoperative or consecutive exotropia. In contrast, only one of the ten patients with normal fusion has required surgery as an aoult. It is noteworthy that in three of the patients with normal fusion their high hypermetropia was corrected with spectacles before the age of 2. They were examined as infants because they had older siblings or parents with accommodative esotropia. They exemplify the importance of early refraction of infants in families with typical accommodative esotropia. 7 Finally, there were two measures of treatment that probably have had little, if any, measureable effect on the course of accommodative esotropia but which have been of major importance to most of these patients. One measure was instructing them how to relax their accommodation and thereby keep their eyes in good alignment when activities such as swimming required removal of their glasses in the presence of others. The blurring of vision caused by even 4 or 5 diopters of uncorrected hypermetropia still permits effective functioning in most social situations. This is exemplified by a sensitive 14year-old girl with high hypermetropia and an amblyopic left eye. She had good alignment with glasses (Fig 1, top)
SWAN
•
ACCOMMODATIVE ESOTROPIA
but if she attempted to see clearly without them a marked esotropia developed (Fig 2, middle). When she relaxed her accommodation and left her distant vision blurred her eyes were in good alignment (Fig 2, bottom). To other sensitive patients the change from "thick glasses" to contact lenses was a landmark event.
REFERENCES 1. Swan KC. Symposium: Accommodative esotropia. Classification and diagnosis. Trans Am Acad Ophthalmol Otolaryngol 1957; 61 :383-9.
2. Costenbader FD. The management of convergent strabismus. In: Allen JH, ed. Strabismus Ophthalmic Symposium (I). St. Louis: CV Mosby, 1950; 334-48. 3. Swan KC, Wahlgren RE. Anaglyphic phenomena in anomalous cor· respondence. Arch Ophthalmol 1957; 57:842-5. 4. Costenbader FD. Symposium: Accommodative esotropia. Principles of treatment. Trans Am Acad Ophthalmol Otolaryngol 1957; 61:390-4. 5. Tongue AC. Accommodative esotropia. Perspect Ophthalmol1981; 5:73-6. 6. Hill RV. A simple method of determining the coordinate requirements of convergence. Am Orthopt J 1955; 5:105-8. 7. Tanner KN, Lockhart. Esotropia in sibling. Trans Pac Coast OtoOphthalmol Soc 1965; 45:405-10.
1145
Abstract: Thirty-nine adult patients treated for typical (refractive) accommodative esotropia in childhood continue to have problems because they have not outgrown their hypermetropia, and the majority have not developed stable binocular vision. Their hypermetropia became maximal (median 5.7 diopters) by age 6, decreased in adolescence, and then stabilized (median 4 diopters). Thirty-eight of the 39 adults wear correcting lenses full-time. Nearly all depend on relaxed accommodation to maintain alignment when they remove their glasses. Ten patients, all of whom received treatment before a constant esotropia developed are essentially orthophoric with glasses and have normal binocular vision. The remainder have small-angle deviations with glasses, 14 with varying degrees of amblyopia and peripheral fusion and 15 with anomalous correspondence and suppression. As adults, only one patient with normal binocular function has required surgery whereas 13 of the patients lacking normal fusion have had surgery for increasing esotropia, postoperative exotropia, or consecutive exotropia. [Key words: accommodative control training, accommodative esotropia, amblyopia, anomalous retinal correspondence, consecutive and postoperative exotropia, hypermetropia.] Ophthalmology 90: 1141-1145, 1983
Most reviews of accommodative esotropia have been concerned primarily with its management in childhood. There has been a need for additional documentation of its course on into adult life and of the ultimate results of treatment. For this reason I have reviewed the course and current status of 39 adults (23-46 years of age) who underwent treatment for accommodative esotropia early in childhood and have been re-examined by me at intervals for 20 or more years. Some have been patients at the Oregon Health Sciences University for nearly four decades and have reached middle-age.
PATIENT SELECTION This review includes only patients who acquired an esodeviation because uncorrected high hypermetropia caused excessive accommodative convergence. With correcting lenses their ratios of accommodative convergence From the Elks Children's Eye Clinic, Department of Ophthalmology, Oregon Health Sciences University, Portland, Oregon. Presented at the Eighty-seventh Annual Meeting of the American Academy. San FranCiSCO, California, October 30-November 5, 1982. Reprint requests to Ker:lneth C. Swan. MD, Oregon Health Sciences University, 3181 S.w. Sam Jackson Park Road, Portland, OR 97201.
0161-6420/83/1000/lJ41/$1.05 © American Academy of Ophthalmology
to accommodation and their amplitudes of accommodation were normal. In accordance with the recommendations of the 1956 American Academy's Symposium on Accommodative Esotropia these patients were classified as having typical (refractive) accommodative esotropia. 1 Excluded from the review were patients with atypical types of accommodative esotropia, that is, those due to an abnormal accommodative convergence to accommodation ratio or subnormal accommodative ability. Also excluded were patients with 2 diopters or more of anisometropia in childhood, vertical deviations, and morphologic abnormalities of either eye. The median age of the first manifestations of esotropia as determined by history and by review of family photographic albums was 26 months, with extremes of 8 months and 71f2 years. In the 71f2-year-old child the esotropia was precipitated by occlusion. Eighteen of the 39 patients had siblings or parents with esotropia. Among the 39 patients in the study were four pairs and one trio of siblings.
INITIAL EXAMINATIONS The median age of my first examination of these patients was 3112 years, with extremes of 8 months to 71f2 years. Most of the children already had developed a con1141
OPHTHALMOLOGY •
OCTOBER 1983 •
Table 1. Changes in Hypermetropia in Childhood
Age
2
3
4
6
8
No. of Patients
Diopters* Median
Range
3.75 4.37 4.75 5.7 5.6
2.5-5.5 3.5-7.37 3.5-8.75 3.62-9.25 3.5-9.5
7
22
37 38 39
* Expressed as spherical equivalents.
stant esotropia. The deviation without glasses was extremely variable but with distant fixation was generally in the 20 to 30 prism diopter range. This placed the blind spot of the deviating eye in correspondence with the point of fixation. Determination of refractive errors was made after multiple instillations of 1% atropine sulfate or 0.25% scopolamine hydrobromide to insure maximal cycloplegia. As shown in Table 1, the maximal median hypermetropia of 5.7 diopters was reached by age 6 years, a level about 1 diopter greater than found by Costenbader. 2 There was a high prevalence of sensory abnormalities. Twenty-four patients had amblyopia in the deviating eye (Table 2). Fifteen patients had anomalous retinal correspondence when tested with after-images, haploscopic devices, and anaglyphic glasses. 3 All had developed a constant esotropia before the age of 3 and with two exceptions had not received treatment before that age. Ten of the 15 patients with anomalous correspondence also had unilateral amblyopia.
METHODS OF TREATMENT In attempts to achieve the ideal goal of normal binocular vision without glasses I treated these patients in accordance with the principles outlined by Costenbader4 in 1956 and recently reaffirmed by Tongue. 5 The initial step was full correction of the hypermetropia. As these patients had normal ratios of accommodative convergence to accommodation and normal accommodative ability, bifocals seldom were required. Anticholin-
Table 2. Initial Visual Acuity in Amblyopic Eye of 24 Children with Typical Accommodative Esotropia 3/200 20/400 20/100-20/50 20/100-20/40 (under treatment)*
1
2 12
9
24 * Occlusion started in nine children too young for accurate acuity determination.
1142
VOLUME 90 •
NUMBER 10
esterase agents were prescribed for a few infants who would not wear glasses consistently. The next major step was management of that deviation which persisted after wearing of the full cycloplegic correction. There was a strong correlation between the amount of residual deviation and the duration of constant esotropia before effective glasses were prescribed. Nearly all of the 14 children with less than 5 prism diopters of residual deviation had had either an intermittent esotropia or a constant esotropia of only a few weeks duration. In contrast, most of the 28 patients who had a residual esotropia of more than 5 prism diopters in distant vision had had a constant esotropia for at least several months before treatment. The management of residual esotropia varied in accordance with the patient's potential for normal binocular single vision. For patients with fusional ability and a deviation of less than 10 prism diopters, base out prisms were incorporated in the glasses in the least strength necessary for binocular single vision. Surgery was undertaken to correct fully larger amounts of residual deviation. In those patients with an inconspicuous deviation and no potential for fusion, no surgery was undertaken and no prisms were prescribed. With noticeable deviation and poor fusional potential, the goal of surgery was to reduce the deviation to cosmetically acceptable levels of esotropia. To lessen the risk of a later exotropia, full correction of the esotropia was avoided. No operations were performed merely to reduce the need for the wearing of spectacles or for deviations that were present only in near vision. Operations primarily to correct residual esodeviation were performed on 20 of the 39 patients before the age of 15. Unilateral inferior oblique recessions were combined with horizontal muscle surgery in two of these patients. Exotropia developed in six patients following correction of their hypermetropia. One, a 4-year-old patient with an amblyopic eye shifted from esotropia to exotropia within a few weeks. Five additional patients gradually shifted from esotropia into exotropia over a period of years. Their median refractive error was over 6 diopters of hypermetropia, and all had amblyopia in one eye. The exotropia first became manifest in near vision and slowly worsened. Reductions in the hypermetropic spectacle corrections to stimulate accommodative convergence were prescribed, but all six patients with consecutive exotropia eventually required surgery. For the 24 patients with amblyopia, occlusion and exercises to stimulate the amblyopic eye were prescribed as soon as the effects of corrective lenses were established. Pleoptics were used in one patient with eccentric fixation and anomalous retinal correspondence. Other orthoptic training was prescribed to develop fusional vergences, especially relative fusional divergence. Antisuppression measures were used in those patients with normal retinal correspondence, but after multiple failures, orthoptic measures to correct anomalous correspondence were discontinued. All patients were trained to keep their accommodation relaxed and vision blurred when they removed their glasses.
SWAN
•
ACCOMMODATIVE ESOTROPIA
Table 4. Operations on 13 Adults Lacking Normal Fusion
COURSE IN ADULT LIFE CHANGES IN REFRACTIVE ERROR
Myopia increases and hypermetropia usually decreases during rapid bodily growth in the second decade of life. For this reason, parents of young children with accommodative esotropia sometimes are given the hope that their children will outgrow most of their hypermetropia, but that did not occur in this series. Their hypermetropia began to decrease by age 10 but, as shown in Table 3, it was still over 4 diopters at age 20 and changed little thereafter. Of the 39 patients, only two had less than 3 diopters of hypermetropia as adults! There were several patients with high (6-8.5 diopters) hypermetropia who had no change in their refractive error and one interesting group of four patients who had no significant change in their amblyopic eye but demonstrated a decrease of 3 or more diopters in the normal eye! INTERPUPILLARY DISTANCE
There is a second "growth factor" that has a favorable effect on accommodative esotropia. I Convergence requirements for near vision increase with widening of the interpupillary distance. The median interpupillary distance of these patients was only 51 mm at age 3 and therefore, their convergence requirement for their usual fixation distance of 26-28 cm was about 16 prism diopters. At age 16, the median interpupillary distance had widened to 64 mm and their convergence requirements had increased to about 22 prism diopters. 7 Lessened esodeviation or greater exodeviation in near vision occurred in nearly all of these patients commensurate with broadening of their facial structures. THE BASIC DEVIATION
The basic deviation, ie, fusion-free alignment, measured with the refractive error corrected and the patients fixating at a distant target was determined with the prism and alternate cover test in all patients. Subjective tests such as the Maddox rod also were made in the 24 patients with normal retinal correspondence. The basic deviation stabilized near orthophoria by the age of 20 in 9 of the Table 3. Changes in Hypermetropia with Age
Age
8 10 14 20 30 40
No. of Patients
Diopters* Median
Range
5.7 5.4 4.25 4.12 4.00 3.87
3.5-9.5 3.5-9.5 3.25-8.5 2.25-8.5 2.25-8.5 1.75-8.5
39 39 39 39 29
6
* Expressed in spherical equivalents.
Initial surgery for esotropia Additional surgery for esotropia Initial surgery for consecutive exo Initial surgery for postoperative exotropia Additional surgery for postoperative exotropia
2 5 3 1 2 13
10 patients with normal fusion but the tenth patient required surgery after her esodeviation gradually increased during her late 30s. Thirteen of the 29 patients lacking the stabilizing effect of fusion required initial or additional operations as adults (Table 4).
RESULTS OF TREATMENT None of the 39 adults have been disabled but all have had enough symptoms to seek re-examination at intervals, usually less than 2 years. Thirty-eight of the 39 are wearing glasses or contact lenses full-time. One 29-year-old patient with 2.25 diopters of hypermetropia in his nonamblyopic eye wears his glasses only for reading. He has a small angle exotropia. The functional status of the 39 adults is summarized in Table 5. Only ten have normal binocular vision, that is, bifoveal perception with stereopsis. There are 14 other patients with varying degrees of unilateral amblyopia and peripheral fusion. They have minimal or no horizontal deviation. None of the 15 patients with anomalous correspondence have regained normal correspondence although several received prolonged orthoptic training in childhood. As their deviations were eliminated or greatly reduced, their angles of anomaly simply became small and/or variable. Only 3 of the 24 patients with amblyopia have had no measureable improvement in their visual acuity. These three have perifoveal eccentric fixation and acuity of only 20/200 with single letters. Three patients had minimal improvement (from 20/200 to the range of 20/100-80). The results otherwise, were favorable in that 18 of the 24 patients now have corrected visual acuity of at least 20/40 in their amblyopic eye and of this group, 8 have corrected acuity of 20/25 or better. Of the three patients who have reached presbyopic age, two have new problems. A 46-year-old woman with 5.6 diopters of hypermetropia and an amblyopic (20/100) eye, has practically no accommodative convergence when Table 5. Functional Status of 39 Adults with Typical Accommodative Esotropia in Childhood Normal binocular single vision Peripheral fusion-minimal amblyopia and some fusional vergences Gross peripheral fusion-residual amblyopia (20/50-20/200) Abnormal retinal correspondence-suppression
10 6
8 15
1143
OPHTHALMOLOGY •
OCTOBER 1983 •
VOLUME 90 •
NUMBER 10
DISCUSSION
Fig 1. Accommodative control. A 14-year-old girl has normal binocular alignment (top) when her 5 diopters of hypermetropia is corrected. A right esotropia (middle) develops when she attempts to see clearly without glasses. Her eyes straighten (bottom) when she leaves her accommodation relaxed. The decrease in acuity does not interfere with activities like swimming which require removal of her glasses.
she looks through the reading addition and is developing a conspicuous exotropia in near vision. The second patient who has normal fusion also has diminished accommodative convergence. She requires 6 diopters base in prism for comfortable single vision with her reading glasses. 1144
Some patients with typical accommodative esotropia in childhood do not require treatment as adults because they wore correcting lenses early in life, developed normal binocular vision, and then lost most of their hypermetropia during adolescence; however, as this study documents, the problems of many patients with typical accommodative esotropia do not end with childhood because they do not outgrow their hypermetropia. Their problems are greater if, in addition, they do not develop stable binocular single vision. With a median hypermetropia of 4 diopters, even those patients who developed exodeviations have become increasingly dependent upon spectacles or contact lenses as their accommodative abilities have decreased. This is understandable because a 30-year-old patient with 4 diopters of uncorrected hypermetropia has the reading capability of an emmetropic individual at age 45! He still may be able to accommodate enough to see distant objects clearly but then stimulates accommodative convergence. In effect, the progressive decrease in accommodative ability in the third and fourth decades makes comfortale binocular single vision without glasses an unrealistic goal for those patients who retain significant amounts of hypermetropia. There were 29 patients in this series who did not receive correction of their high hypermetropia early enough to develop normal fusion. Their problems continuing into adult life document that the price of delaying treatment of accommodative esotropia in infancy is high indeed. Lacking normal fusional vergences, their binocular alignment in intermediate and near vision is determined primarily by the degree of accommodative effort. In addition to varying degrees of amblyopia and almost total dependence upon glasses for maintenance of alignment with clear vision, one third already have required surgery either for recurrences or progression of esotropia or for postoperative or consecutive exotropia. In contrast, only one of the ten patients with normal fusion has required surgery as an aoult. It is noteworthy that in three of the patients with normal fusion their high hypermetropia was corrected with spectacles before the age of 2. They were examined as infants because they had older siblings or parents with accommodative esotropia. They exemplify the importance of early refraction of infants in families with typical accommodative esotropia. 7 Finally, there were two measures of treatment that probably have had little, if any, measureable effect on the course of accommodative esotropia but which have been of major importance to most of these patients. One measure was instructing them how to relax their accommodation and thereby keep their eyes in good alignment when activities such as swimming required removal of their glasses in the presence of others. The blurring of vision caused by even 4 or 5 diopters of uncorrected hypermetropia still permits effective functioning in most social situations. This is exemplified by a sensitive 14year-old girl with high hypermetropia and an amblyopic left eye. She had good alignment with glasses (Fig 1, top)
SWAN
•
ACCOMMODATIVE ESOTROPIA
but if she attempted to see clearly without them a marked esotropia developed (Fig 2, middle). When she relaxed her accommodation and left her distant vision blurred her eyes were in good alignment (Fig 2, bottom). To other sensitive patients the change from "thick glasses" to contact lenses was a landmark event.
REFERENCES 1. Swan KC. Symposium: Accommodative esotropia. Classification and diagnosis. Trans Am Acad Ophthalmol Otolaryngol 1957; 61 :383-9.
2. Costenbader FD. The management of convergent strabismus. In: Allen JH, ed. Strabismus Ophthalmic Symposium (I). St. Louis: CV Mosby, 1950; 334-48. 3. Swan KC, Wahlgren RE. Anaglyphic phenomena in anomalous cor· respondence. Arch Ophthalmol 1957; 57:842-5. 4. Costenbader FD. Symposium: Accommodative esotropia. Principles of treatment. Trans Am Acad Ophthalmol Otolaryngol 1957; 61:390-4. 5. Tongue AC. Accommodative esotropia. Perspect Ophthalmol1981; 5:73-6. 6. Hill RV. A simple method of determining the coordinate requirements of convergence. Am Orthopt J 1955; 5:105-8. 7. Tanner KN, Lockhart. Esotropia in sibling. Trans Pac Coast OtoOphthalmol Soc 1965; 45:405-10.
1145