Clinical characteristics of surgically treated adult strabismus

BACKGROUND

Strabismus is present in approximately 4% of the population with most forms becoming clinically evident in infancy and childhood. Adult strabismus, including that resulting from recurrent childhood deviations, varies in etiology, presentation, symptomatology, and response to treatment. This report is intended to prospectively characterize adults who required surgical correction of their strabismic deviation.

METHODS

Beginning in 1991, a prospective computerized database was collected that contained all clinical, laboratory, and surgical information on the adult ocular motility service at the Scheie Eye Institute and The Children's Hospital of Philadelphia (Philadelphia, Pa). Analysis of those patients who underwent surgical correction of their strabismus is included in this report. Demography, clinical characteristics, and surgical procedures including results were analyzed separately in adults with their strabismus beginning before visual maturation (BVM) (9 years of age) and after visual maturation (AVM).

RESULTS

A minimum of 6 months and average of 1.8 years follow up is reported on 262 procedures in 255 patients with an average age of 37 between January 1991 and January 1996. Sixty-two percent of patients had their strabismus onset BVM. Fifty-one percent of BVM patients and 80% of AVM patients had incomitant deviations. Adjustable suture surgery was performed on 97% of all patients, with 28% of BVM and 57% of AVM patients having multiplanar surgery. Successful motor alignment was achieved in 85% of all patients after one surgical procedure. Sensory success was achieved in 81% of all AVM patients and 25% of all BVM patients. Subjective success was 94% in both groups of patients.

CONCLUSIONS

Numerous differences exist between childhood and adult strabismus characteristics and response to surgery. Although strabismus surgery is effective, differences in results reflect the varied physiology regarding etiology, pathophysiology, and symptomology. Classification into AVM and BVM groups will provide continued clarity for future studies.

Ocular manifestations of genetic and developmental diseases

Ophthalmic genetics is a rapidly expanding field that includes both clinical and basic sciences. Clinical descriptions of syndromes and new diagnostic testing both reflect the increase in knowledge and technology of molecular biology. Technologic advances have resulted in old diseases being described in new ways and being attributed to new pathophysiologic mechanisms. This review is intended to update the past year's contributions in ophthalmic genetics. Discussion is by disease type, which is familiar to most clinicians.

Comitant esodeviation resulting from neurologic insult in children

PURPOSE

Our purpose was to establish whether comitance was a common or uncommon finding in children with esodeviation associated with a neurologic insult.

METHODS

A retrospective chart review was performed of children with acquired esodeviation associated with an identifiable neurologic insult.

RESULTS

Examinations of 30 children seen over a 2-year period were analyzed. Twenty-two (73%) had brain tumors. Twelve (40%) had comitant esodeviation, and the other 18 (60%) had incomitant measurements. Of the patients with comitant esodeviation, 6 had normal abduction OU (two after recovery from bilateral sixth nerve palsies), and 6 had mild or minimal abduction deficits. Moderate or severe abduction deficits were associated with incomitant measurements.

CONCLUSIONS

Comitant esodeviation can be common in children with identifiable neurologic insults.

Successful visual rehabilitation after neonatal penetrating keratoplasty

BACKGROUND

Penetrating keratoplasty in infancy and childhood has traditionally met with limited visual success due to a combination of unique physiology and technical problems in this patient population. With the advances in microsurgical instrumentation, corneal preservation, and visual developmental physiology ophthalmologists are finding increasing indications for penetrating keratoplasty in the childhood population. The long term results of neonatal penetrating keratoplasty in two patients with unilateral congenital corneal opacification are reported.

METHODS

Penetrating keratoplasty was performed on one eye in each of two infants within the first 3 weeks of life. Amblyopia treatment and optical therapy have been continued since surgery.

RESULTS

After 6 years both grafts have remained clear. One patient developed the infantile esotropia syndrome. Visual development using Snellen optotypes is age normal for both transplanted eyes.

CONCLUSIONS

Penetrating keratoplasty when combined with optical correction and amblyopia therapy may restore and preserve vision in selected patients with congenital corneal opacification if performed in the neonatal period.

Adjustable horizontal rectus recession surgery for disparate distance-near ocular deviations

Strabismic deviations which display incomitance changing from distance fixation to near fixation are the result of many disturbances of both the supranuclear and infranuclear ocular motor system. This report details the surgical treatment and outcome of 6 patients with disparate distance-near deviations due to different etiologies. The surgical procedure involves recessing all four horizontal recti on both eyes using the adjustable suture technique. The approach to surgery consisted of operating on the vergence angle with the larger deviation with a bilateral lateral rectus recession (BLREC) or a bilateral medial rectus recession (BMREC) and simultaneously operating on the smaller vergence angle, treating the total induced deviation with the bilateral recession not used first (remaining BLREC or BMREC). All patients had a significant decrease in their distance-near disparity, increased horizontal comitance, normalization of their accommodative convergence to accommodation ratios, and resolution of diplopia. A four horizontal recti muscle, adjustable suture recession is another technique that can be added to the treatment regimens for distance-near disparity strabismic syndromes.

Ocular manifestations of genetic and developmental diseases

Although ophthalmic involvement in developmental and genetic abnormalities has been recognized for centuries, it is only recently, due to new discoveries in molecular biology, that our classification and pathophysiology of congenital eye diseases have been advanced. In the next few years these advances will increasingly influence aspects of diagnosis classification, and therapy in ophthalmology. Tests for acquired and inherited diseases in opthalmology are being revolutionized by biotechnical innovations. The molecular genetics of ocular diseases is currently undergoing changes in classification due to intense investigations using advanced biotechnology. The potential for new treatment modalities, such as gene therapy, for molecular eye diseases, once thought to be pure fiction, is now a reality. This paper will outline recent changes in classification, organization, and general knowledge regarding inherited eye diseases.

Visually impaired children with sensory defect nystagmus, normal appearing fundi and normal ERGS

The differentiation of congenital motor nystagmus (CMN) from sensory defect nystagmus (SDN) in early life is a common diagnostic problem, since their wave forms are indistinguishable. A diagnosis of SDN is made when fundal or ERG abnormalities are present. CMN is generally diagnosed by exclusion. This approach can lead to late or incorrect diagnosis, and to the overlooking of important genetic implications. In addition, the classification of congenital nystagmus into pure motor and sensory types is inadequate. The authors present case reports illustrating this problem and suggest strict criteria for a diagnosis of CMN. They also point out that a miscellaneous group of rare disorders of the macula tend to be overlooked and misdiagnosed.

The use of hyaluronic acid during adjustable suture surgery

We prospectively studied the force required to move an extraocular muscle after adjustable suture surgery with and without the perioperative use of hyaluronic acid (Healon). The 15 muscles that received hyaluronic acid averaged 15.0 g of force to move the muscle 2.0 mm which was significantly different than the average force of 36.15 g required for the 13 control muscles. The decreased force required to adjust the muscle along with potential antiinflammatory properties of hyaluronic acid make this a useful adjunct during adjustable suture surgery.

Hypopyon uveitis in patients with acquired immunodeficiency syndrome treated for systemic Mycobacterium avium complex infection with rifabutin

OBJECTIVE

Iridocyclitis has been identified as a dosage-dependent side effect in patients with the acquired immunodeficiency syndrome (AIDS) who are treated for Mycobacterium avium complex (MAC) infection with systemic rifabutin. We reviewed cases of acute hypopyon uveitis occurring in patients with AIDS to establish whether there was an association.

DESIGN

Retrospective case series.

SETTING

Outpatient clinic and inpatient hospital-based ophthalmology referral practice and infectious disease specialty service.

PATIENTS

Seven patients with AIDS, aged 10 to 40 years, presenting with acute unilateral hypopyon mimicking infectious endophthalmitis.

MAIN OUTCOME MEASURES

Findings from complete ophthalmological evaluation and ancillary laboratory testing.

RESULTS

At the time of presentation, all seven patients were receiving treatment for MAC infection with rifabutin (dosage range, 300 to 600 mg/d) and clarithromycin. Results of microbiological investigations in five patients were negative. Iridocyclitis became bilateral in all seven patients, and hypopyon developed in the contralateral eye in five of seven patients. Hypopyon resolved rapidly with intensive topical corticosteroid therapy. Residual inflammation responded to topical corticosteroids with or without reduction of the rifabutin dosage.

CONCLUSIONS

Concomitant use of rifabutin, clarithromycin, and fluconazole may precipitate hypopyon uveitis in patients with AIDS being treated for MAC infection.

Application of the potassium-titanyl-phosphate laser during extraocular muscle surgery: technique and histopathology

We determined laser parameters and delivery system requirements for successful use of the potassium-titanyl-phosphate (KTP) laser for strabismus surgery and its histopathologic effect on extraocular muscle, tendon, sclera, and cornea of human and rabbit eyes. Enucleated cadaver eyes and exenterated rabbit orbital contents were used. Using a 200-microns fiberoptic tip delivery system, varying laser energies were used to perform muscle insertion site and corneal damage, tenotomies, and myotomies. Pulse durations of 0.5 second and energies above 0.8 watt were needed for tenotomy or myotomy. No damage to the surrounding tissues or sclera was observed with laser tenotomy or myotomy performed 0.5 mm from the insertion site. Energy above 0.8 watt applied directly caused full thickness disruption. In comparison to scissor myotomy, the laser provided charring of the superficial tissues. This study shows that the KTP laser can be safely and accurately used for extraocular muscle tenotomy or myotomy.

The visual-evoked response in infants with central visual impairment

We studied ten children with central visual impairment with a known neurologic defect and an abnormal visual-evoked response who had results of repeat electrophysiologic testing evaluated at the Children's Hospital of Philadelphia from December 1989 through July 1991. Central visual impairment is defined as poor visual function with a normal anterior visual pathway. Age at first examination ranged from 5 to 48 months with a followup of two to 31 months. Repeat visual-evoked response testing showed improvement in seven patients and no change in three. Grating acuity as measured by the Teller acuity card procedure, performed in nine of ten patients, improved in seven, showed no change in one, and declined in one. We found a potentially favorable prognosis for those infants with central visual impairment, despite an initially abnormal visual-evoked response. We used a clinical approach to this disorder to improve diagnostic categorization and prognostic capabilities in central visual impairment.

Ophthalmic features and visual prognosis in the Treacher-Collins syndrome

The ocular findings and visual prognosis were reviewed in 24 patients with the Treacher-Collins syndrome who were evaluated in the craniofacial clinic in the Division of Pediatric Ophthalmology at Children's Hospital of Philadelphia between 1980 and 1991. All patients had some abnormality. Vision loss was present in 37% of patients. Amblyopia was present in 33%, significant refractive errors were present in 58%, and anisometropia was documented in 17%. Strabismus was present in 37% and significant lid and adnexal abnormalities were seen in 96%. The prognosis for normal vision in at least one eye is good but vision loss secondary to amblyopia is more resistant to treatment owing to other medical problems and social concerns.

The intraoperative oculocardiac reflex as a predictor of postoperative vaso-vagal responses during adjustable suture surgery

Adjustable suture surgery has become a popular method of strabismus correction in those cases in which results are less predictable, such as reoperations, thyroid ophthalmopathy, and blind eyes. Complications related to adjustable strabismus surgery are, in general, no different than those related to standard surgical techniques. We noticed a subgroup of patients who experienced significant vaso-vagal responses (V-VR) during postoperative adjustment and sought to discover a method of identifying these patients prior to adjustment. Sixty patients were studied prospectively from July 1991 to July 1992. All patients had surgery under general anesthesia and were adjusted 24 hours later. A positive oculocardiac reflex (OCR) occurred when a 10% or greater intraoperative change in heart rate was associated with traction on an extraocular muscle. A positive V-VR postoperatively consisted of one or more subjective findings (dizziness, light-headedness, nausea, or body temperature changes), and two or more objective findings (10% or greater change in heart rate, hypotension, pallor, diaphoresis, vomiting, disorientation, or loss of consciousness). Variables studied for predictive value included OCR, age, sex, strabismus type, previous surgery, muscle adjusted, and systemic disease. Twenty-five patients (41.6%) had a positive V-VR during adjustment. Twenty-seven patients (45%) had a positive OCR. Eighty-five percent of patients with a positive OCR and 9% of patients with a negative OCR had a positive V-VR. Younger patients were also more likely to have a positive V-VR. A positive intraoperative OCR under general anesthesia during strabismus surgery is highly predictive of a postoperative V-VR during planned adjustment.

Insertion site dynamics and histology in a rabbit model after conventional or suspension rectus recession combined with ipsilateral antagonist resection

We have used a rabbit model to study insertion movement, rotational forces, disinsertion forces, and histology of the surgically created insertion site after recession of the inferior rectus (IR) using a conventional (CONV) or suspension (SUS) technique combined with an ipsilateral superior rectus (SR) resection. During the 5-week observation period, the CONV and SUS recessed IR showed an initial posterior movement followed by an anterior movement while all resected SR had an initial posterior movement which remained stable. SR rotational forces increased and IR remained constant throughout the 5-week observation period. There were no rotation force differences between the SUS and CONV recession techniques. Disinsertion forces showed an initial large decrease in force followed by a gradual increase to preoperative levels by 3 postoperative weeks. Disinsertion force differences between the CONV and SUS recessions were observed for 5 weeks after surgery. Histologic analysis showed a delayed inflammatory response on the SUS recession compared to the CONV recession and at the middle of the insertion compared to the poles which was minimized by 3 weeks after surgery.

Congenital unilateral fibrosis, blepharoptosis, and enophthalmos syndrome

The authors report four cases of the rarest form of the congenital fibrosis syndrome. This disorder is exhibited in infancy as unilateral blepharoptosis, strabismus, limited ductions, globe displacement (enophthalmos and blepharoptosis), and decreased vision, usually due to amblyopia. Forced ductions are positive and surgical exploration confirms anomalous muscle structure. Computed tomography and magnetic resonance imaging studies in these four patients were diagnostically beneficial, showing extraocular muscle and tendinous insertion involvement, and poorly defined intraconal and extraconal masses that had the appearance of scar or inflammatory tissue. All patients had globe displacement. The opposite eye and intracranial contents were normal in all of our patients. Results of histopathologic examination obtained at surgery in three of these patients show replacement of affected structures by fibrous tissue and included the extraocular muscles, orbital fat, Tenon's capsule, and conjunctiva.

Ocular and adnexal findings in patients with facial microsomias

The authors reviewed the ocular findings in 49 patients with facial microsomias not considered part of a known syndrome. Five patients had bifacial microsomia, and 44 patients had hemifacial microsomia. These patients were evaluated in the Craniofacial Clinic in the Division of Pediatric Ophthalmology at Children's Hospital of Philadelphia between the years 1979 and 1989. Ocular or adnexal abnormalities were present in 67% of patients. Visual loss was present in 8% of eyes. Amblyopia was present in 16% of patients. Significant refractive errors were present in 27% of patients, and anisometropia was documented in 8%. Strabismus was present in 22% of patients, and significant lid and adnexal abnormalities were seen in 41%. Because ocular or adnexal findings present in a significant percentage of patients with more mild forms of facial microsomias, regular examinations to uncover and treat these abnormalities are recommended.

Epibulbar squamous cell carcinomas in brothers with Xeroderma pigmentosa

We report two brothers aged 6.6 and 5 years old with the De Sanctis-Cacchione variant of Xeroderma Pigmentosa. They had typically severe skin, and ocular and neurologic involvement. Both had epibulbar squamous cell carcinomas. The oldest presented with a large, invasive, epibulbar mass of the left eye which required enucleation. He also had an invasive squamous cell carcinoma of the right lower lid. The younger brother presented with a smaller papillomatous lesion at the medial limbus of the right eye. After removal, this was found to be squamous cell carcinoma in-situ. Flow cytometry done on the tumors revealed diploidy. The case descriptions, histopathology, and discussion of ocular manifestations are presented.