[Abnormal head turn in a patient with Brown's syndrome]. / Ungewöhnliche Kopfzwangshaltung bei Brown-Syndrom.

BACKGROUND: We report on an eight-year-old boy, who was presented in our clinic because of head turn. The cause of the tortecollis (ocular or general) in this case was and still cannot be explained. Only by applying extensive prism adaptation tests it was possible to prove the ocular character of the head turn. CASE REPORT: An eight-year-old boy with Brown's syndrome was referred to us because of a head tilt to the left side. Six months previously surgery on the M. obl. superior of the right eye was performed in another clinic. No improvement of the head tilt could be observed after the operation. In addition, an exotropia became decompensated. Under a 3-day occlusion of one eye, no change of the head turn and the squint could be measured. No other cause of the head turn could be found by an orthopaedist and a paediatrist. Under a prism of 20 cm/m basis in and 10 cm/m basis against the positive vertical deviation, the head tilt decreased, so that we decided to do a second surgery. The head tilting had not resumed at one year after the surgery. CONCLUSIONS: Although the initial diagnostic findings ruled out an ocular cause, it was possible to lessen the head tilting with the aid of the prism adaptation test. This case study emphasises the usefulness of a prism adaptation test of several days duration in order to validate an ocular cause of head turn and to determine an adequate indication for surgery.

[Botulinum toxin injections for the treatment of strabismus. Which indications are still useful today?]. / Botulinumtoxin-Injektionen zur Behandlung von Strabismus. Welche Indikationen haben sich bewährt?

Botulinum toxin treatment was originally developed 25 years ago by Alan B. Scott to produce reversible weakening of extraocular eye muscles in humans (chemodenervation). The following uses are still helpful today in comparison with eye muscle surgery, prism applications etc.: Preoperative evaluation of possible postoperative diplopia in patients in whom this cannot be done by means of prisms or traction test, etc. Acute paretic loss of ocular muscle function when surgical treatment of the ocular muscles is not yet possible but the patient is obviously disturbed by diplopia or a forced head posture. This applies especially to VI cranial nerve paresis. Depending on the surgical approach in VI nerve palsies, Botulinum toxin may be injected in the medial rectus muscle before muscle transposition surgery to loosen contracture. Strabismus in acute Graves' disease. In strabismus in other conditions, Botulinum toxin is mostly inferior surgical treatment of the ocular muscles; this is the case, for example in congenital esotropia or horizontal strabismus in adults. While the reversibility of the Botulinum toxin A effect by fading out after 3-4 months is seen as an advantage, it does also mean that in these cases of constant strabismus it is necessary to keep repeating the injections.

[Bitemporal hemianopia in road traffic]. / Bitemporale Hemianopsie im Strassenverkehr.

BACKGROUND: Patients suffering from pituitary adenomas and diseases of the chiasma typically show a bitemporal hemianopia. The residual undisturbed nasal visual fields of both eyes should have an extension of (at least) 120 degrees and are according to the actual German traffic rules (FeVAndV) for cars of the classes A, B, M, L and T. The intact half fields fit geometrically to one virtual normal field, that seems to correspond in the centre of a normal field. Reports on this problem often do not address correctly the questions of suitability for participation in road traffic. PATIENTS: The case of a patient with typical bitemporal hemianopia illustrates the sensorial peculiarities: the functioning temporal retinal halves do not correspond. This patient suffered additionally from disturbing diplopia due to a small-angle exotropia. The extent of the performed eye muscle surgery was selected to induce a slight overcorrection, i. e., resulting in 3 to 5 degrees esotropia. This eliminated the diplopia, but resulted in a vertical scotoma of the extension of the esotropia. CONCLUSIONS: In bitemporal hemianopia the undisturbed nasal visual half fields do not add up to a "nearly normal field of one eye". Moreover, either diplopia or--much more dangerous in traffic--a central vertical scotoma is the result. The explanation for this is a sliding of the hemifields of each eye without stabilisation by corresponding areas of the retinas of the right and left eyes. The peripheral extension of the visual field is not the key to the problem to imagine how a patient with typical bitemporal hemianopia will visualise daily life and traffic. In bitemporal hemianopia there is substantially no eligibility for driving a car or motor bicycle in road traffic.

[Influence of body position on ocular cycloposition in patients without binocular vision]. / Lageabhängigkeit der Augenstellung in der torsionalen Ebene bei Patienten ohne Binokularsehen.

PURPOSE: Positionally induced cyclotorsion could be an important factor concerning correction of astigmatism in refractive surgery. Previous studies have shown no influence of body position on cycloposition in healthy subjects with normal binocular vision. METHODS: 10 subjects (median value of age 44.2 years) without binocular vision due to an organic eye disease or to strabismus were examined using three-dimensional video-oculography (3D-VOG). This non-invasive method can record changes in the position of both eyes simultaneously in the x-, y- and z-axes. The cycloposition of the eyes was recorded first in a seated position with both eyes open (test 1), then in a supine position with the right eye closed (test 2), then in a supine position with occlusion of both eyes (test 3), and then in a supine position with both eyes open (test 4). In each of these 4 situations, the eyes were recorded for 1 minute. Cyclovergence was calculated as the difference between the right and the left eye positions. RESULTS: The range of cycloposition of the right and left eye in all 4 tests was very small. 95 % confidence intervals for cycloposition of the right and left eyes and for cyclovergence: cycloposition right eye/cycloposition left eye/cyclovergence: 0.72;0.76/- 0.07;0.01/0.71;0.79 (test 1), 0.23;0.29/0.19;0.33/- 0.81;- 0.63 (test 2), - 0.92;0.7/- 0.51;- 0.37/- 0.79;- 0.45 (test 3), 0.14;0.52/- 0.07;0.31/0.59;0.21 (test 4). There was no statistically significant difference of the cycloposition between the 4 test situations. CONCLUSIONS: The cycloposition of the eyes does not significantly change between seated and supine positions of the body, either in subjects with, or without binocular vision. This means for refractive surgery that a correction of astigmatism, to be performed in the supine position of the patient, can be based on a measurement of the axis of astigmatism obtained in the seated position.

[Head-tilt test in unilateral and symmetric bilateral acquired trochlear nerve palsy]. / Das Kopfneigephänomen bei einseitigen und beidseitig symmetrischen Trochlearisparesen.

BACKGROUND: The head-tilt phenomenon (difference between the vertical deviations with an ipsilateral and contralateral head-tilt by 45 deg. each) occurring in patients with a superior oblique palsy has traditionally been explained by the lacking contraction of the superior oblique muscle within the synkinetic movement of ocular counterrolling. However, using a computer model, Robinson showed that the superior oblique palsy itself causes only a relatively small head-tilt phenomenon. Adaptive mechanisms amplifying the otolith reflex were suggested to explain the increase of the head-tilt phenomenon in the course of time. In order to reduce the abnormal head posture required for binocular vision, the otolith reflex would be amplified, accepting the greater vertical deviation when the head is tilted to the paretic side . QUESTION: If the head-tilt phenomenon were solely caused by the lacking contraction of the superior oblique muscle, it should be greater in bilateral than in unilateral superior oblique palsies. If an adaptive mechanism were acting to reduce the abnormal head posture, the head-tilt phenomenon should not be greater, and could even be smaller in bilateral than in unilateral superior oblique palsy, because in bilateral (symmetric) trochlear nerve palsies the vertical deviation at straight gaze is already small or absent without adaptation. PATIENTS AND METHODS: We have carried out a retrospective comparison of 10 patients with bilateral symmetric superior oblique palsies and 10 patients with unilateral superior oblique palsy. In all cases, the palsy was acquired and had been present for at least 1 year. RESULTS: The patients with bilateral superior oblique palsy had a head-tilt phenomenon ranging from 0 to 7 degrees (median, 2 deg.). The patients with unilateral superior oblique palsy had a head-tilt phenomenon between 2 and 13 degrees (median, 8 deg.). The difference was significant (p = 0.0117). CONCLUSIONS: The head-tilt phenomenon is smaller in long-standing bilateral symmetric superior oblique palsies than in long-standing unilateral superior oblique palsy. This finding supports the hypothesis that in unilateral superior oblique palsy, an adaptive mechanism augments the head-tilt phenomenon by an amplification of the otolith reflex. However, we presume that the amplification of the otolith reflex is only a side effect of the adaptive change of the vertical fusional vergence tonus and thus the price of the improved vertical fusion, rather than a compensatory mechanism.

[Fibrin glue for closing conjunctival wounds in ophthalmic surgery]. / Fibrinklebung der Bindehaut in der Ophthalmochirurgie.

BACKGROUND: Tissue adhesives offer the attractive prospect of sutureless surgery and provide a mechanism for repairing potentially difficult surgical wounds. We examined the ability of fibrin glue--instead of sutures--to close conjunctival wounds at the end of different ophthalmic surgeries. METHODS AND PATIENTS: Between 2002 and 2003 the fibrin glue Beriplast was used in our department to close the conjunctival wound in 100 eye muscle surgeries, 10 scleral buckling procedures in retinal detachment, and 20 pars plana vitrectomies. RESULTS: No patient showed postoperative adverse or allergic reactions, bacterial infections, inflammation, or delayed healing. The healing process of the conjunctiva takes a similar time course as in suture closure, but without disturbing suture ends and knots. In children with extensive Tenon's fascia, adaptation of the conjunctiva is safer using sutures. The necessary time using fibrin glue is reduced to one-fourth of the usual 4-8 min necessary for suturing the conjunctiva. The costs for fibrin glue are the same as for Vicryl 9/0, i.e., approximately 18-20 Euros per patient. CONCLUSIONS: Fibrin glue for closing conjunctival wounds results in good adaptation, is time saving, effective, and not more expensive than a suture with a high-end needle. Especially the thin atrophic conjunctiva in adults will tear using sutures in contrast to the very fast and effective adaptation with fibrin glue. Application of fibrin glue is limited in children with extensive Tenon's fascia: in these patients a suture is superior for good adaptation of the conjunctiva.

Use of preoperative assessment of positionally induced cyclotorsion: a video-oculographic study.

PURPOSE: Positionally induced cyclotorsion could be an important factor concerning correction of astigmatism in refractive surgery. The method of binocular three dimensional infrared video-oculography (3D-VOG) was used to determine a possible influence of body position on cyclotorsion. METHODS: 38 eyes (19 healthy subjects, median value of age 25.5) with normal binocular vision were examined using 3D-VOG. This method records ocular motions and positions of both eyes simultaneously in the x, y, and z axis. Cycloposition of the eyes was recorded first in a seated position (both eyes open, test 1), then in a supine position (right eye closed, test 2), occlusion of both eyes (test 3), both eyes open (test 4). Cyclovergence was calculated as the difference between the right and the left eye positions. RESULTS: The range of cyclotorsion of the right and left eye in all four tests was between 1.13 degrees excyclotorsion and 0.34 degrees incyclotorsion. There was no statistically significant difference of the median values for torsion for the four test situations. Concerning the influence of body position on cyclotorsion, a statistically significant difference between the different test positions and settings did not exist. Median values for right/left torsion/cyclovergence were: 0.17/0.04/0.02 (test 1), -0.31/-0.71/-0.16 (test 2), -1.09/-0.60/0.82 (test 3), 0.28/0.28/-0.82 (test 4). CONCLUSIONS: Cyclotorsion does not significantly change between seated and supine position in subjects with normal binocular vision and stable fixation. In these subjects, an erroneous refractive surgery due to incorrect measurement of the axis of astigmatism in the seated position and performing the refractive surgery in the supine position, is very unlikely.

[Accuracy of measurements of video-refractometry in higher ametropia]. / Messungenauigkeit der Videorefraktometrie bei höheren Ametropien.

BACKGROUND: Measurement of refraction of non-cooperative patients is a real challenge for the ophthalmologist. Retinoscopy produces exact results in experienced hands, but requires practice and time. The Videorefractor VRB 200 (manufactured by Tomey, Erlangen) was especially designed for refracting children. The aim of this study is to prove the accuracy of this tool in measuring refraction. MATERIAL AND METHODS: 259 patients (age 10 month to 77 years) were measured with the VRB 200. Each patient was examined by retinoscopy in cycloplegia and refracted with the Topcon autorefraktor RM-A 6000. Ametropia was evoked at 5 emmetropic volunteers by lenses of different power, placed in a trial frame. These measurements were performed with and without use of cycloplegic drugs. RESULTS: The VRB 200 showed an average error of spherical equivalent at ametropia of the range -4 to +4 Diopters (dpt) < 2 dpt. At higher ametropia the error grew increasingly. Repeated measurements of one patient showed high variation of the results. Astigmatism was measured worse by growing magnitude, especially at diagonal axis (45 degrees and 135 degrees). Anisometropia > 2 dpt has been discovered in only 72%. It was possible to examine many infants and handicapped patients, which was impossible by using the RM-A 6000. An examination by retinoscopy was possible in all cases, but needed a lot of time and patience. CONCLUSIONS: The concept of good handling suffers especially by the increasing inaccuracy at ametropia beyond +/- 4 dpt. At this state of development the VRB 200 is no alternative in practical use to the conventional retinoscopy.

Remission of superior oblique myokymia after microvascular decompression.

Superior oblique myokymia (SOM) is an ocular motility disorder characterized by oscillopsia, vertical or torsional diplopia, sometimes combined with pressure sensation. Although the pathophysiological basis is unclear, isolated case reports have documented its association with intracranial pathological processes. We present a case of SOM associated with a vascular compression of the fourth nerve at the root exit zone. Following microneurosurgical decompression, SOM completely resolved and paralysis of the fourth nerve occurred. This was less disturbing.

Measurement of recti eye muscle paths by magnetic resonance imaging in highly myopic and normal subjects.

PURPOSE: To analyze the path of extraocular muscles (EOMs) quantitatively in highly myopic subjects with and without restricted eye motility versus control. To elucidate the cause of the acquired motility disorder in patients with high myopia. METHODS: Thirty-three orbits were imaged using a Magnetom or Siemens Vision (Siemens, Erlangen, Germany; both 1.5 Tesla) MRI (magnetic resonance imaging) scanner. Coronal T1-weighted, spin-echo images were obtained with repetition time of 550 msec and echo time of 15 msec. Subjects had to fixate in different positions of gaze. Orbits of three patient groups were analyzed: group 1 (n = 14), patients with high axial myopia and restricted eye motility (average axial length, 31.4 mm; refractive error more than -15 D); group 2 (n = 8), subjects with high axial myopia and normal eye motility (average axial length, 29.2 mm); control group (n = 11), emmetropic subjects with normal eye motility (average axial length, 23.6 mm). RESULTS: Highly myopic patients showed significant displacements of recti EOMs in comparison with control subjects. Mean displacements, measured in the plane 3 mm anterior to the globeoptic nerve junction in primary gaze, were in group 1, lateral rectus (LR) 2.9 mm (2.5 downward, 1.4 medial), medial rectus (MR) 1.3 mm downward and in group 2, LR 1.4 mm (1.3 downward, 0.6 medial) and MR 1.2 mm downward. In groups 1 and 2 the inferior rectus (IR) was displaced 1.3 mm medially and upward. In both groups of myopic patients the superior rectus (SR) was displaced 1.5 mm medially and downward. CONCLUSIONS: In patients with high axial myopia, displacements of all recti EOMs can be detected by MRI. Displacements of SR, MR, and IR were very similar in groups 1 and 2 versus control. LR displacement into the lateral and inferior quadrant of the orbit was greatest in patients with restricted eye motility. Thus, LR displacement is probably the major pathophysiological factor for the restrictive motility disorder in high myopia. EOM dislocations can be explained by myopia-associated alterations in the orbital connective tissues confining EOM positions in relation to the orbital wall.

[Disturbances of binocular vision in macular heterotopia]. / Störung des Binokularsehens bei Makulaheterotopie.

BACKGROUND: Tractive translocation of the macula (secondary macular heterotopia) may result in disturbance of binocular vision. The report of a case shall discuss the sensorial problems of these patients. HISTORY AND SIGNS: We report of a 40-years old male who had decreased visual acuity and loss of binocular vision for several years due to episodes of uveitis with intravitreous hemorrhage and cataract formation. After bilateral vitrectomy and cataract extraction a good visual acuity was restored in both eyes. Postoperatively, the patient monocularly complained about disturbed egocentric localization (tilting of the visual environment, "past-pointing") and metamorphopsia. Binocularly he was confused by doubled vision with tilted images. Both maculae showed a tractive translocation of 15 degrees downward. Measurements of binocular alignment with the tangent screen showed an excyclotropia of 8 degrees and an exotropia of 7 degrees in all directions of gaze. Haploscopic examination with fusion images demonstrated that sensorial fusion was not possible even with perfect ocular alignment due to disturbed relative retinal localization (obligate fixation disparity). THERAPY AND OUTCOME: Initially, full time occlusion of the left eye was required. After improvement of symptoms occlusion therapy was slowly tapered. Within one year the patient had learned to suppress the image of his left eye and reported only minor residual visual disturbances even without occlusion of his left eye. CONCLUSIONS: Secondary translocation of the macula monocularly results in a disturbance of egocentric localization and in metamorphopsia. Binocularly doubled vision with tilted images and a loss of sensorial fusion are seen. With monocular vision, perceptual adapting to the aberration in egocentric localisation is possible within weeks by reallocation of the retinal meridians in the central nervous system. Binocular improvement of symptoms is limited to the learning of suppression. Improvement of binocular symptoms by adaptation of retinal correspondence does not occur.

[Pyogenic granuloma following eye muscle surgery]. / Pyogenes Granulom nach Augenmuskeloperation.

BACKGROUND: A pyogenic granuloma developing after eye muscle surgery is a rare complication. It can impair aestethical results and ocular motility. PATIENT AND METHODS: A 7-year-old girl presented in our department with recurrence of a conjunctival granuloma following a bimedial retroequatorial myopexia an excision of conjunctival suture granuloma in the left eye. Clinically, a nodular painless and reddish mass was found at the nasal limbus in the interpalpebral zone. Other results of ocular examinations were limitation of adduction and elevation, mild amblyopia (visual acuity 0.8) due to microstrabismus of 1 degree. After surgical excision following the initial biopsy, the histopathologic study established the diagnosis of pyogenic granuloma. After recessing residual conjunctiva and Tenon's fascia in 10 mm distance from the limbus the conjunctiva was fixed to the sclera. The sclera between the limbus and the conjunctiva was left uncovered. Reepithelialisation of the bare sclera occurred after few days. RESULTS: No further symptoms were observed during a follow-up time of 1 year. CONCLUSIONS: The rapid growth and appearance as well as the clinical examination may imitate another tumor necessitating surgical excision and histopathological study. Bare sclera-technique is a suitable method for plastic reconstruction.

Microvascular decompression for superior oblique myokymia: first experience. Case report.

Superior oblique myokymia (SOM) is a rare eye movement disorder presenting as uniocular rotatory microtremor due to intermittent contractions of the superior oblique muscle. Medical treatment usually fails to provide long-term benefit for the patient and has considerable side effects. Surgical alternatives including tenotomy or partial tenectomy of the superior oblique tendon often result in incomplete resolution of the visual symptoms. The authors report a patient who experienced immediate cessation of disabling SOM following microvascular decompression of the fourth nerve at the root exit zone. Temporary double vision at downgaze resolved 5 months after surgery. There was no recurrence of oscillopsia during a follow-up of 22 months to date. From this single observation it appears likely that vascular compression of the trochlear nerve could be a significant pathophysiological factor contributing to SOM. In the hands of an experienced surgeon, microvascular decompression at the brainstem exit zone of this nerve may evolve as the method of choice for selected cases of disabling SOM.

[Night driving capacity of ophthalmologically healthy persons of various ages]. / Nachtfahreignung augengesunder Personen verschiedener Altersstufen.

UNLABELLED: In 1970 Aulhorn and Harms made fundamental recommendations for the night driving ability of motorists as well as for the corresponding examination methods. Reduced night driving ability of persons over the age of 60, as well the established limits for twilight vision and glare sensitivity, and their relevance to night-time collisions has been re-examined. PATIENTS AND METHODS: A total of 117 normal volunteers between 10 and 79 years of age underwent ophthalmological examinations including measurement of contrast acuity and glare sensitivity by means of the Mesotest II (Oculus, Germany). RESULTS: Contrast acuity and glare sensitivity deteriorate in an age-dependent fashion. Thus, night driving ability decreased with increasing age. The majority part of persons over the age of 60 were not able to fulfill the actual criteria for night driving ability according to the recommendations of the German Ophthalmological Society (DOG). CONCLUSIONS: In the present population, nearly 40% of persons over the age of 60 have reduced night driving ability. Since Lachenmayr showed in the BAST study the correlation of reduced night driving ability and car accidents, this emphasizes the importance of ophthalmological check-ups for motorists at this age.

[Twilight vision and glare sensitivity in monofocal and multifocal pseudophakia]. / Dämmerungssehvermögen und Blendempfindlichkeit bei monofokaler und multifokaler Pseudophakie.

UNLABELLED: Reduced contrast sensitivity and an increase in glare sensitivity may be observed in patients with cataract and in pseudophakic persons. By means of Mesoptometer II we examined night driving ability according to the recommendations of the German Ophthalmological Society (DOG) in patients with cataract, monofocal or multifocal pseudophakia. METHODS: A total of 176 patients were included in the study: 85 patients (68.8 years) with a monofocal standard IOL, 50 patients (66.1 years) with a multifocal IOL type AMO Array SSM-26NB/SA-40NB and 41 patients with beginning cataract (66.4 years). The corrected visual acuity of all patients was at least 0.7. Contrast acuity was examined at a luminance setting of 0.32 cd/m2; glare sensitivity was measured at a luminance of 0.1 cd/m2 with additional glare source. RESULTS: Night driving ability (both criteria accomplished) was found in 41% of patients with binocular monofocal IOL and in 38% of patients with binocular multifocal IOL. CONCLUSION: Elderly pseudophakic patients and patients with beginning cataract cannot sufficiently fulfill the criteria for night driving ability because of contrast and glare sensitivity. It seems to be indispensable, for the parameters mentioned to be carefully examined and for patients to be informed that night driving ability may be impaired, even if visual acuity is sufficient.

[Magnetic resonance imaging of of the right extraocular muscle paths in healthy persons and in patients with high myopia]. / Magnetresonanztomographische Messungen des Verlaufs der geraden äusseren Augenmuskeln bei Normalpersonen und bei Patienten mit hochgradiger Kurzsichtigkeit.

PURPOSE: To investigate the paths of the rectus extraocular muscles (EOMs) in patients with high axial myopia, using high-resolution magnetic resonance imaging (MRI). METHODS: Coronal MR images (T1 weighting) of the orbit were obtained with controlled gaze. Positions of recti EOMs were measured digitally in the middle of the orbit, using the NIH-image analysis software. Orbits of three different patient groups were analysed. Group 1 (n = 14 orbits): Patients with high axial myopia and restrictive eye motility. Group 2 (n = 8 orbits) subjects with high axial myopia and normal eye motility. Controls (n = 11 orbits) with normal eye motility and no refractive error. RESULTS: In comparison to the controls, patients with high axial myopia were found to have significant misplacement of the recti EOMs. Thus in group 1 (group 2 within brackets) the lateral rectus muscle (LR) was misplaced 2.9 (1.4) mm into the lower temporal quadrant p < 0.001 (p = 0.07). The course of the superior rectus muscle (SR) was shifted 1.5 (1.5) mm medially p = 0.02 (p = 0.03) and the path of the inferior rectus muscle (IR) 1.3 (1.3) mm medially p = 0.06 (p = 0.06). The medial rectus muscle (MR) showed a 1.3 (1.2) mm downward mislocation p = 0.01 (p = 0.07). CONCLUSIONS: In patients with high axial myopia (group 1 and group 2) misplacement of all rectus EOMs could be demonstrated by high resolution MRI with controlled gaze. All patients showed an approximately equal amount of MR, SR and IR mislocation. However, misplacement of the LR was significantly greater in patients with high myopia and restrictive eye motility (group 1) than in those without restrictive ocular motility (group 2), p = 0.03. We therefore assume that LR downward mislocation is a major determinant for restrictive eye motility in high myopia.

New approach in strabismus surgery in high myopia.

AIMS: To develop appropriate methods of eye muscle surgery in highly myopic patients with esotropia and hypotropia, with respect to the pathological findings in high resolution magnetic resonance imaging (MRI). METHODS: 35 patients with unilateral or bilateral high myopia and strabismus--that is, axial length of the globe averaged 29.4 mm. Multiple coronal, transverse, and parasagittal MRI image planes were obtained using a Siemens Magnetom 1.5 tesla MRI scanner. In 15 patients with a pathological plane of recti extraocular muscles found by MRI and confirmed intraoperatively, a new technique of eye muscle surgery was performed to re-establish the physiological muscle plane. This was checked postoperatively in addition to the measurement of alignment and motility by MRI. RESULTS: The new MRI finding of a dislocation of the lateral rectus (LR) into the temporocaudal quadrant by 3.4 mm requires new surgical techniques. Only fixing the LR in the physiological meridian at the equator with a silicone loop ('guide pulley') or a non-absorbable suture is a causal therapy. This yields alignment and improves abduction and elevation. CONCLUSIONS: If the described misalignment of the LR is detected by MRI, a common high dosage recess-resect procedure for esotropia may even aggravate the deviation. The most important aim of eye muscle surgery is to normalise the pathological path of the LR. The restoration of the physiological function of the dislocated LR is remarkable.

[Measurements of ultrasound reflectivity of oculomotor muscles in endocrine orbitopathy]. / Sonographische Reflektivitäts-messungen der Augenmuskeln bei endokriner Orbitopathie.

BACKGROUND: In the course of Graves' disease (GD) the extraocular muscles become fibrotic after an acute inflammatory stage. Differentiation of these two stages is important for therapy. MATERIALS AND METHODS: First, we examined the eye muscles of 30 healthy volunteers with the 10 MHz-B probe (Ultrascan) Digital B 2000) and then those of 20 patients with GD. The thickness was measured in the longitudinal displayed muscle always with the same gain. The amplitude of the highest inner muscle spikes expressed as a percentage of amplitude of retina-sclera spike provided the internal reflectivity. The stage of GD was determined by clinical signs. RESULTS: In GD, thickness of inferior and medial rectus was significantly enhanced in both the inflammatory and fibrotic stages, while internal reflectivity was only significantly higher in the latter stage. CONCLUSIONS: Ultrasound discriminates the acute from chronic course of GD in eye muscles and thus provides a very useful tool for making therapeutic decisions.

[Nuclear magnetic resonance tomography diagnosis of eye motility disorder in high-grade myopia for planning an eye muscle operation]. / Kernspintomographische Diagnostik der Motilitätsstörung bei hoher Myopie zur Planung der Augenmuskeloperation.

BACKGROUND: This study was conducted to elucidate the etiology of the acquired, restrictive motility disorder in patients with severe myopia by magnetic resonance imaging (MRI) and intraoperative situs and to verify existing theories about strabismus to develop appropriate methods of eye muscle surgery. METHODS: Thirty-five patients with unilateral or bilateral high-degree myopia and strabismus, i.e., axial length of the globe averaged 29.4 mm. Multiple coronal, transversal and parasagittal MRI planes were obtained using a Siemens Magnetom (SP 63) 1.5 Tesla MRI scanner (TR = 550 ms, TE = 15 ms; field of view = 21 x 21 cm; pixel matrix = 256 x 512; 3 acquisitions; slice thickness 2 mm; distance factor 0.25). In addition, in a dynamic MRI the patient had to fixate with the less restricted eye for 50 s in different gaze positions. All data were validated by measurements during strabismus surgery. Twenty normal orbits were studied in control MRI scans. RESULTS: The major MRI finding was dislocation of the lateral rectus in the anterior and midorbital region at an average of 3.4 mm into the temporocaudal quadrant in 13 cases with the typical eso- and hypotropia. This dislocation will reduce the abducting torque of the lateral rectus and create depressing and extorting torques. Two-anatomical explanations are possible: (1) increasing stretch of the lateral rectus because of temporocranial distension of the globe and inability of intermuscular membranes and pulleys to stabilize the path of the lateral rectus; (2) dehiscence of the lateral levator aponeurosis. The restrictive motility disorder was never caused by contact between the enlarged globe and the bones of the orbital apices. CONCLUSIONS: Until now, an abnormal path of recti EOMs has been known only in Duane's syndrome. Prior to strabismus surgery in patients with high-degree myopia, an orbital MRI scan may be useful. If misalignment of the lateral rectus is detected, the most important aim of eye muscle surgery is to normalize the pathological path of the lateral rectus. MRI morphometry in severe myopia may give additional information on the anatomy of the orbit and biomechanical mechanisms of strabismus. Our findings demonstrate the necessity of fixation-controlled MRI scans.

[Binocular problems caused by aniseikonia and anisophoria after cataract operation]. / Binokulare Probleme durch Aniseikonie und Anisophorie nach Katarakt-Operation.

BACKGROUND: Cataract and refractive surgery aiming at emmetropia, runs the risk to induce binocular problems, e.g. asthenopia or diplopia. If the compatibility concerning binocularity is solely estimated by the calculation of the difference of the retinal image sizes, using intraocular lens formulas or so-called "aniseikonia-programs", important physiological facts are not considered. The actual amount of the aniseikonia, this is the difference of the image size which the patient perceives subjectively, depends on 3 parameters: 1. the optically induced difference of the retinal image size, 2. the spatial density of the retinal photoreceptors and the size of the receptive fields, 3. a possibly existing anomalous retinal correspondence for different retinal image sizes. Besides aniseikonia, the induction of postoperative anisophoria by the required spectacle correction is a considerable aspect. Aniseikonia and anisophoria can cause fusional problems or diplopia because of the mentioned parameters and/or disparity of the retinal images. CASE REPORT: Cataract surgery should reduce a monolateral high myopia, aiming emmetropia, in axial anisometropia. This resulted in one exemplary case in high aniseikonia with complaints, while in other, comparable patients only a small amount of aniseikonia could be measured by haploscopy. This preoperative refractive situation is comparable to refractive surgery. In a second case with symmetrical myopia of -4 D, binocular problems with diplopia and asthenopia were induced after monolateral cataract surgery by the combination of a moderate aniseikonia and anisophoria. CONCLUSIONS: To predict the actual postoperative aniseikonia it is necessary for the patient to wear a contact lens preoperatively for a short time to measure the aniseikonia by haploscopy, particularly prior to refractive surgery in axial length ametropia. Due to the different sizes of the receptive fields of the retina, different postoperative aniseikonias may result in spite of similar axial length anisometropia. The individual tolerance of an adult for a postoperatively created anisophoria is hardly predictable. It is obvious that the fusional stress ensued from aniseikonia and anisophoria adds or multiplies. In contrast to horizontal eye movements, vertical eye movements can hardly be compensated by head movements, as the use of bi- or multifocals requires a down gaze of about 30 degrees. Here a height-balance-prism could help.