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A Bacskulin

Publications and source records attributed to A Bacskulin.

11 recordsLinked to original sources
PubMed2000

[Analysis of the dynamics of the ciliary muscle during accommodation].

BACKGROUND: The magnitude of anterioaxial shift of the human ciliary muscle during accommodation and its ceasing of ciliary function with advanced age are still unknown. PATIENTS AND METHODS: A total 105 patients (aged 10-91 years) were examined by high-resolution ultrasound biomicroscopy during disaccommodation and voluntary accommodation. Accommodative changes in the total area of the ciliary muscle and in the outer contour were quantified with a specially developed software program for automatic contour determination. RESULTS: A significant anterior shift independent of age was observed in the total area of the ciliary muscle and defined points on the outer contour of the muscle in the range of 56-121 microns, while the inward displacement was less obvious. A decrease in the magnitude of configurational changes during accommodation was observed with age. CONCLUSION: The new software program could be useful in further investigations of the accommodative process and evaluation of the potential causes of presbyopia.

Accommodation, Ocular↗
PubMed2000

New osmotically active hydrogel expander for enlargement of the contracted anophthalmic socket.

BACKGROUND: Clinical anophthalmia is characterized by the absence of an eyeball within the orbit and can result in overall growth retardation of the facial skeleton. The goal of treatment consists of fitting a serial prosthesis following rapid expansion of the contracted socket as soon as possible to achieve cosmetically acceptable eyelid and orbital symmetry. METHODS: Four children, aged 3-11 months, were treated by implantation of an anhydrous, highly hydrophilic tissue expander into the rudimentary conjunctival sac. With hydration of up to 98% in 72 h, the copolymer of methylmethacrylate and vinylpyrrolidone acts like an osmotically self-inducing socket expander. RESULTS: In the course of 2 months the previous contracted socket was enlarged, the horizontal lid length increased and the hydrated expander could be exchanged for a custom-made glass prosthesis. CONCLUSION: Preliminary results suggest that this new device can be used to avoid early plastic surgery of the eyelid. In addition, it also may enlarge the volume of the bony orbit.

Anophthalmos↗
PubMed1999

Neuromyotonia of the abducens nerve after hypophysectomy and radiation.

The clinical signs of the rarely encountered ocular neuromyotonia consist of transient involuntary tonic contraction and delayed relaxation of single or multiple extraocular muscles, resulting in episodic diplopia. With a mean time delay of 3.5 years, this motility disorder frequently follows tumor excision or adjuvant radiation near the skull base. Ocular neuromyotonia may reflect inappropriate discharge from oculomotor neurons with unstable cell membranes because of segmental demyelinization by tumor compression and radiation-induced microangiopathy. In the present paper, the authors present the case of a 53-year-old patient with a history of transsphenoidal hypophysectomy and adjuvant radiotherapy, who underwent strabismus surgery for abducens palsy.

Abducens Nerve↗
PubMed1996

[Ultrasound biomicroscopy imaging of accommodative configuration changes in the presbyopic ciliary body].

Direct observation of the position of the ciliary body was possible only in cases of gross anatomic, and probably also functional, abnormalities. Utilizing the 50 MHz ultrasound biomicroscope, we investigated the profile changes of the ciliary body in ten eyes of ten patients, ranging in age from 54 to 86 years while they were ocusing on a target at a distance and afterwards on an object up close. After electronic image processing of ten single video pictures from each accommodative status, a summarized picture for every accommodative status was obtained. In seven of ten cases, during accommodation a remarkable shift of the ciliary body was observed anterior to the iris and in the direction of the lens equatore, while the iridociliary body contact zone became wider in five of the ten eyes. Ultrasound biomicroscopy allows visualization of the dynamics of the accommodative process. As the human ciliary body does not lose its contractility in the senium, the loss of accommodation in presbyopia is mainly caused by age-related changes of the lens and capsula.

Accommodation, Ocular↗
PubMed1996

An adjuvant afterloading brachytherapy device for use after orbital exenteration in patients with orbital malignancies.

In cases of malignant diseases situated within the orbit and threaten to extend beyond it, removal of the orbit and periorbital contents may be indicated, followed by adjuvant chemotherapy or irradiation. An effective radiotherapy device for treatment of residual or suspicious cancer in the enucleated orbit consists of an external-beam radiation source (60Co) and an intraoperatively fitted mould as a guide for the flexible afterloading tubes using a 192Ir source. Considering the physical dose distribution and the local situation, this therapy permits a high dose with homogeneous dose distribution to the target area of the orbit but also allows significant dose reduction to adjunctive critical structures. Four patients with different orbital malignancies were treated by means of a combination of percutaneous radiotherapy with afterloading brachytherapy following orbital exenteration. The individual mould of the orbital cavity is modeled at the end of the operation. The technique of radiotherapy, dose distribution, and follow-up of the disease are demonstrated. Orbital malignancies with an extremely poor prognosis may profit from the application of this combined radiotherapy to avoid supraradical surgical intervention.

Adenocarcinoma↗
PubMed1995

[Continuous ultrasound biomicroscopic imaging of accommodative changes in the human ciliary body].

BACKGROUND: Slitlamp observations of the position of the ciliary body behind the iris root are possible only in cases of gross anatomic, and probably also functional, abnormalities. This study was performed to investigate physiological changes of the human ciliary body configuration during accommodation. MATERIAL AND METHODS: We used the 50 MHz ultrasound biomicroscope to measure the ciliary body changes in 5 left eyes of normal subjects during accommodation, while the right eye, wearing corrective spectacles, focussed Snellen letters at a distance of 3 m. For desaccommodation plus lenses were utilized, while negative lenses were applied to blur vision as a stimulus for accommodation. During postprocessing the best images of the video sequence were recalled on a monitor and the profile of the ciliary body was manually drawn on a transparent folder. For interpretation we used a projection system with vector analysis. RESULTS: During accommodation there is a shift of the ciliary body anteriorly toward the scleral spur and in the direction of the lens equator. In 4 out of 5 eyes a contact between the ciliary body and the posterior iris surface could be demonstrated. There was a measurably widening of the anterior chamber angle in 3 out of 5 eyes. CONCLUSIONS: Ultrasoundbiomicroscopy seems to be a way for assessing ciliary body deformation during accommodation. Our results are in accordance with histologic and gonioscopic findings and confirm biomechanical theories of the accommodation process. Further investigations including online digital image processing will be necessary to evaluate accommodation in its complexity.

Accommodation, Ocular↗
PubMed1993

Analysis of a terminal Xp22.3 deletion in a patient with six monogenic disorders: implications for the mapping of X linked ocular albinism.

The molecular characterisation of chromosomal aberrations in Xp22.3 has established the map position of several genes with mutations resulting in diverse phenotypes such as short stature (SS), chondrodysplasia punctata (CDPX), mental retardation (MRX), ichthyosis (XLI), and Kallmann syndrome (KAL). We describe the clinical symptoms of a patient with a complex syndrome compatible with all these conditions plus ocular albinism (OA1). He has a terminal Xp deletion of at least 10 Mb of DNA. Both the mother and sister of the patient are carriers of the deletion and show a number of traits seen in Turner's syndrome. The diagnosis of ocular albinism was confirmed in the patient and his mother, who shows iris translucency, patches and streaks of hypopigmentation in the fundus, and macromelanosomes in epidermal melanocytes. By comparative deletion mapping we can define a deletion interval, which locates the OA1 gene proximal to DXS143 and distal to DXS85, with the breakpoints providing valuable starting points for cloning strategies.

Abnormalities, Multiple↗
PubMed1993

[Results of pars plana vitrectomy in chronic uveitis in childhood].

During 1986-1991 vitreous surgery was performed in 5 girls and 8 boys (age range 2-15 years) with chronic uveitis. In 6 cases a combined lensectomy-vitrectomy was performed because cataract was present, so that the results generally refer to 19 eyes. We found a low rate of postoperative complications. During a follow-up period of 6 months to 5 years (average 2 years and 1 month), 12 of the 19 eyes showed a significant visual improvement. Preoperatively, 8 eyes were found to be affected by cystoid macular edema; in 7 of these cases remarkable regression of the edema was observed after surgery. In two-thirds of cases the intensity of the inflammation decreased, so that the dose of corticosteroids could be reduced postoperatively. Our results suggest that vitrectomy for chronic uveitis in children is a relatively safe and successful treatment. In order to prevent irreversible complications and amblyopia surgery should be performed in an early stage of the disease.

Adolescent↗
PubMedDate not supplied

Efficiency of pupillary stretching in cataract surgery.

PURPOSE: To assess the efficiency of pupillary stretching with iris hooks in poorly dilatable pupils during phacoemulsification. METHODS: Forty eyes with maximal preoperative mydriasis less than 4.5 mm (mean 3.9 mm S.D. 1.0) received bimanual pupillary stretching according to the technique of Miller and Keener (1994). RESULTS: Small pupils were mainly caused by long-term pilocarpine therapy (n = 21), posterior synechia (n = 11) or diabetic iridopathy (n = 7). With multidirectional stretching, the pupil could be enlarged to mean 6.6 mm (S.D. 0.66), lasting throughout phacoemulsification. The effect of stretching was significantly greater in eyes with synechias, but no significant differences in post-operative pupil motility was observed between the three subgroups. Six eyes with pronounced postoperative inflammation responded well to antiinflammatory treatment. CONCLUSIONS: Done with routine surgical instruments, bimanual pupillary stretching seems to be an easy, safe and effective procedure for enlarging small pupils by an average of 2.7 mm during phacoemulsification, especially in eyes with posterior synechias.

Aged↗