Biomedical subjects

H P Vick

Publications and source records attributed to H P Vick.

14 recordsLinked to original sources

PubMed2004

[Lateral orbital decompression for Graves' orbitopathy. Indication, surgical technique, and treatment success].

PURPOSE: In Graves' disease a discrepancy between volume increase of the orbital soft tissues and fixed volume of the orbital cavity leads to exophthalmos. The patients do not only feel cosmetically disfigured, they often complain about more or less painful retroorbital pressure sensation or show symptoms of compressive optic neuropathy or corneal exposure because of a significant lid lag. To solve this problem, different orbital decompression techniques have been developed. This is to report about our results with a modified Dollinger technique for lateral orbital decompression. PATIENTS AND METHODS: A total of 27 patients aged 19-76 years (mean: 45.1 years) with Grave's ophthalmopathy were recorded who had undergone orbital decompression by a lateral approach between June 1999 and April 2003. The modified Dollinger technique was performed by deepening the osteotomy to the level of the sphenoid wing and by additional resection of intraconal fat. RESULTS: The reduction of exophthalmos achieved after decompressive surgery averaged 2.9 +/- 1.1 mm. Of the patients whose indication for orbital decompression was a compressive neuropathy, the visual acuity improved postoperatively for 3 lines. Of the 16 patients with preoperative retrobulbar pressure sensation, 12 had no complaints after the operation. Remarkably no significant impairment of the ocular motility resulted after surgery. CONCLUSIONS: Decompression of the orbit by the modified Dollinger technique is a safe and effective approach to reduce exophthalmos, retrobulbar pressure sensation, and compression neuropathy as a result of diffusely elevated orbital tissue tension. In the case of direct compression of the optic nerve in the orbital apex, additional medial orbital wall decompression has to be considered.

Adult↗

PubMed1998

[Cyclophotocoagulation with the diode laser. Study of long-term results].

UNLABELLED: To assess the clinical effectiveness of glaucoma therapy with diode laser cyclophotocoagulation, 106 eyes (51 eyes with primary open-angle glaucoma, 22 eyes with secondary glaucoma, 10 eyes with narrow-angle glaucoma, 23 eyes with other glaucomas) of 87 patients were treated. Using a diode laser coupled with a fiberoptic probe, ending in a focusing tip, all eyes were treated with 24-30 spots over 360 degrees and 2.8-3.5 J of energy, 1.5 mm posterior to the limbus. The intraocular pressure was obtained over a period of time until 8-24 months after operation. Additionally, morphological changes of the ciliary body were observed in 25 eyes by means of ultrasound biomicroscopy. RESULTS: The IOP decreased from a baseline mean of 25.0 +/- 5.7 mm Hg to 17.6 +/- 5.3 mm Hg directly after operation and increased slightly to 18.0 +/- 6.0 mm Hg in the following 24 months. Successful control of IOP (IOP constantly < 22 mm Hg or pain relief in blind eyes) occurred in 90 of 106 eyes (84.9%). In 23 eyes more than one treatment was given. In 6 eyes another IOP-reducing operation had to be performed. In 19 eyes slightly elongated intraocular inflammatory reactions were seen, without any serious complications. The morphological investigations showed in 22 of 25 cases temporary edema of the ciliary body. A temporary detachment of the ciliary body was seen in 8 eyes. CONCLUSIONS: Diode laser cyclophotocoagulation is an effective and safe procedure to reduce IOP in different types of glaucoma over a long time. Postoperatively, a temporary inflammatory reaction of the ciliary body was observed with no correlation to the degree of reduction of the IOP.

Adult↗

PubMed1997

[In vivo imaging of corneal innervation in the human using confocal microscopy].

To date, descriptions of the structure of corneal innervation have only been possible on the basis of histological techniques. Confocal microscopy represents a new method for the structural examination of the cornea in vivo. Through our examinations we first defined the control group and then proceeded to record the reinnervation of donor tissue after perforating keratoplasty. We used the confocal slit-scanning video-microscope Microphthal to examine 40 corneas from 20 normal volunteers, 15 donor corneas and 5 eyes after enucleation for ocular tumors. These results were compared to our findings from postoperative checks on 14 patients after perforating keratoplasty (from 1 month to 2 years). With this system we were able to see nerves in the middle and in the superficial stroma. The course of these nerves can be followed, as well as their branching in the subepithelial plexus. Nerve fibers from superficial stromal nerves penetrate Bowman's membrane and create the basal epithelial plexus in the region of the basal epithelium. Seven months after perforating keratoplasty the first stromal nerves could be seen in the central corneal area. The first central reinnervation in the region of Bowman's membrane as well as in the basal epithelium was not detected until 15 months after operation. With confocal microscopy we have the potential to study the morphology of corneal innervation in vivo and in fresh donor tissue. For the first time it is possible to perform non-invasive morphological studies of reinnervation of the human cornea after surgical treatment.

Adolescent↗

PubMed1996

Corneal reinnervation following penetrating keratoplasty--correlation of esthesiometry and confocal microscopy.

Thus far assessment of corneal reinnervation after penetrating keratoplasty has been possible only by esthesiometry techniques. Since the introduction of confocal microscopy, we have been capable of performing structural corneal in vivo examinations. The purpose of our study was to correlate esthesiometry results with confocal microscopy findings. We used a Cochet-Bonnet esthesiometer and a Microphthal confocal microscope to investigate corneal grafts in vivo. A total of 46 eyes were examined preoperatively and for up to 3 years after penetrating keratoplasty. At 8 weeks after keratoplasty the first stromal nerves were detected in the periphery of the graft. The first nerves in the middle and superficial stroma of the graft center were observed at 7 months after surgery. Reinnervation of the central basal epithelium was found at 2 years after keratoplasty. The highest level of sensitivity was detected in young patients with reinnervation of the basal epithelium. Confocal microscopy enables us to correlate morphologically and functionally corneal reinnervation after surgery. The present study shows that corneal reinnervation is influenced by the amount of time elapsing after surgery, the patient's age, and the preoperative diagnosis. In none of our patients was normal nerve morphology or sensitivity observed during the follow-up period. Comparison of the morphology of nerves seen in eyes after nonsurgical trauma with that observed in corneal grafts indicates that surgically induced scar formation may limit nerve regeneration in grafts.

Adolescent↗

PubMed1995

[Prevention of postenucleation syndrome: the hydroxylapatite silicone implant. Preliminary experimental studies and initial clinical experiences].

An orbital implant after enucleation compensates for volume deficiency and increases prosthesis motility. In the literature, however, an extrusion rate of orbital implant between 10 and 25% is reported. Since the introduction of hydroxylapatic ceramics (HAC), these numbers have been reduced considerably. The HAC, which is derived from corals, has a rough surface and requires a scleral covering for implantation. The HAC, which is made in the laboratory, can be produced with smoother surfaces, so that a homoplastic covering is no longer mandatory. A composite implant was developed to improve prosthesis motility further. This consists of artificial HAC at its anterior surface to guarantee safe tissue integration; the posterior part of the implant is manufactured from silicon rubber to create a jointlike structure in Tenon's capsule. Integration of the porous HAC in the orbital soft tissues has been tested and confirmed by animal experiments. After 30 full HAC implants and 25 composite implants, only one extrusion occurred. In all other cases, compatibility proved to be excellent; transmission of the motility to the prosthesis was moderate to good. Examinations comparing prosthesis motility and computer tomographically evaluated implant motility enabled the analysis of deficits in motility transmission of the implant for the artificial eye.

Animals↗

PubMed1974