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H Witschel

Publications and source records attributed to H Witschel.

At least 37 records · Page 2Linked to original sources
PubMed1996

Characteristic distribution of deposits in recurrent granular corneal dystrophy.

Granular corneal dystrophy can recur after penetrating keratoplasty. In those cases as in the early primary manifestation of the disease, deposits are found predominantly in the superficial corneal layers. At a later stage, stromal deposits can also be seen. We describe an additional particular location of deposits and correlate clinical with histological findings in three corneas from two patients. Deposits were found mainly superficially within the graft and around the edge of the transplant along the scar between host and donor cornea. We suggest that the deposits are of epithelial origin, though their production by stromal cells cannot be excluded. Chemical interactions are discussed as an explanation for the characteristic distribution of the deposits.

Adult↗
PubMed1995

Transscleral suture fixation of posterior-chamber lenses after cataract extraction associated with vitreous loss.

From 1987 to 1993, 21 patients who had undergone complicated cataract extraction that was associated with vitreous loss and transscleral suture fixation of the posterior-chamber lens (PC-IOL) in one eye (group A) and uncomplicated in-the-bag implantation of the PC-IOL in the fellow eye (group B) were followed prospectively. The follow-up period was 29.5 months (SD, +/- 17.0 months) in group A and 36.6 months (+/- 24.0 months) in group B. Visual acuity did not differ significantly between the two groups (P = 0.60, Wilcoxon test). In all, 17/21 patients in group A and 16/21 patients in group B achieved a visual acuity of > or = 20/40. Postoperative refractions measured in group A were +0.68 D more hyperopic than those measured in group B (P < 0.04). This result was consistent with the postoperative finding of a significantly deeper anterior chamber in group A (mean, 0.44 mm; P < 0.03). The accuracy of the desired postoperative refraction was poorer in group A. The risk for retinal detachment, cystoid macular edema, and intraocular pressure elevation was increased in patients who had had capsular defects and vitreous loss during cataract extraction. Nevertheless, transscleral suture fixation of PC-IOLs in patients with complicated cataract extractions associated with vitreous loss can give acceptable visual results. We recommend that +0.5 D be added to the calculated IOL power when severe complications require transscleral suture fixation of the PC-IOL during cataract extraction.

Aged↗
PubMed1995

[Antigen pattern in choroid melanoma in correlation with immunoscintigraphy].

We have reported that the sensitivity of immunoscintigraphy in ocular melanoma is fairly low in comparison with (metastasizing) cutaneous melanoma. No significant correlation was found between the histological data for ocular melanoma and the immunoscintigraphic results. We therefore wanted to see whether we could demonstrate an antigen pattern that was different from that of cutaneous melanoma, which might explain our previous results. Our study comprised tumor tissue from 20 patients with ocular melanoma who had undergone previous immunoscintigraphic examination. Using immunohistochemical techniques, tumor immunoreactivity was investigated against 225.28S, the antibody used for immunoscintigraphy, on cryosections in 12 cases, and against anti-HMB-45, and anti-S-100 and anti-vimentin on paraffin sections in all 20 patients. In summary, there was marked immunohistochemical heterogeneity, and none of the antibodies examined showed a significant correlation with immunoscintigraphy. Even 225.28S that was used for the immunoscintigraphic examination did not retrospectively allow a predictable immunoscintigraphic outcome. When comparing our results with the literature on cutaneous melanoma we were also able to confirm differences in immunoreactivity with regard to the other antibodies. We conclude that the comparatively poor results in ocular immunoscintigraphy obtained with 225.28S are due to antigenic differences between ocular and cutaneous melanoma.

Antigens, Neoplasm↗
PubMed1994

Paraffin induced sclerosing lipogranuloma of eyelids and anterior orbit following endonasal sinus surgery.

During the past 5 years we have seen 10 patients who had developed sclerosing lipogranuloma of the lid and orbit after endonasal sinus surgery with subsequent ipsilateral monocular haematoma. The histopathological examination of all and the additional nuclear magnetic resonance spectroscopic examination of four surgical specimens in combination with the typical clinical course led to the conclusion that the granulomas were caused by small paraffin droplets. These in turn stemmed from the ointment plugs applied to the sinuses at the end of the operation, and were washed out into the surrounding tissues by the postoperative haemorrhage. As the chronic and recurring granulomas can lead to considerable cosmetic and functional impairment, the application of ointment plugs at the end of sinus surgery should be abandoned, especially when peri- or postoperative bleeding occurs.

Adult↗
PubMed1994

[Late complications and functional results at least 5 years following pars plana lentectomy for congenital cataract].

Pars plana or pars plicata lentectomy was introduced for congenital cataract at the University Eye Clinic of Freiburg 12 years ago. Records of 32 patients (48 eyes) who were operated on during a period of 7 years were retrospectively analyzed to determine the anatomical and functional results in comparison to previous methods of treatment for congenital cataract. The documented follow-up was at least 5 years long (maximum 11 years, mean 7.3 years). Seventeen patients had bilateral, 15 patients monolateral cataract operations. Thirteen eyes were operated on during the first 2 months of life, and 31 of the 48 eyes during the first year. Sixteen of the 48 eyes had additional malformations, like microphthalmus, different stages of persistent hyperplastic primary vitreous, or anterior chamber malformation. Visual acuity was at least 20/50 at the last visit in 3 of 15 eyes after monolateral lentectomy and in 19/33 eyes after bilateral lentectomy. Twenty-four children are now able to attend a regular school; only one child is attending a school for the visual handicapped; another child attends a school for deaf children. Postoperatively, secondary cataract or a retropupillary membrane was found in two eyes. Glaucoma developed in two eyes, requiring additional surgery. Postoperative retinal detachment caused by a giant tear complicated the postoperative course in one case. The anatomic results turned out to be better than after discission and aspiration with fewer postoperative complications like secondary cataract, glaucoma, or retinal detachment. The functional outcome is mainly dependent on good postoperative orthoptic and pleoptic management of the children.

Adolescent↗
PubMed1994

[Immunoscintigraphy results in the comparison of ocular with cutaneous melanoma].

For several years, immunoscintigraphy (IS) using a 99mTc-labeled monoclonal antibody for tumor localization has been used as an additional tool in the diagnosis of malignant melanoma. The aim of our study was to verify previously published data with respect to our own patients and to correlate immunoscintigraphic results with histological findings. In particular, we wanted to compare the outcome of IS in ocular melanoma with that in cutaneous melanoma. We examined 28 patients (15 females, 13 males, average age 64 years) with clinically suspected ocular melanoma. IS was performed using the monoclonal antibody 225.28S (Tecnemab-K-1, Fa. Sorin/Solco), and images were obtained in a standard fashion (planar) as well as with the SPECT technique. In 16 patients, the tumor was examined afterwards histologically. The control group consisted of 102 patients with histologically proven metastasizing cutaneous melanoma who were investigated by IS in an identical fashion. In contrast to the literature published so far, we demonstrated a positive IS reaction in only 42% (and 56% in histologically proven cases, respectively) in our patients with ocular melanoma, while in patients with cutaneous melanoma, we found a sensitivity of more than 80%. In the 3 patients who turned out not to have ocular melanoma, we found one false-positive reaction (subretinal hemorrhage). No correlation was found between the various histological features of ocular melanoma and the immunoscintigraphic results. We conclude that IS using the antibody 25.28S is of limited value in patients with ocular melanoma and should only be recommended in selected cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Choroid Neoplasms↗
PubMed1993

[Chronic lipogranuloma (paraffin granuloma) of the eyelids and orbits after endonasal paranasal sinus operation].

During the last five years 10 patients received surgical treatment in our eye clinic for tumours of the eyelids and the orbit that had developed after endonasal sinus surgery. In most patients the first signs of lid or orbital involvement had occurred 4 weeks after ENT surgery and after a unilateral or bilateral postoperative haematoma had subsided. The histological examination of the surgical specimens showed chronic sclerosing lipogranuloma containing large vacuoles surrounded by epithelioid and giant cells, typical of a so-called paraffin granuloma. MR-spectroscopy detected high concentrations of paraffin in the specimens of 3 patients. Since paraffin is a constituent of many ointments, we assume that the granulomatous reaction was elicited by the ointment tampons routinely applied to the wound area following sinus surgery. The bleeding acted as a vehicle to distribute the paraffin into the surrounding tissues.

Adult↗
PubMed1993

[Isovolemic hemodilution in central retinal vein occlusion in patients less than 50 years of age].

AIM--Aim of the study was investigation of the effect of isovolemic hemodilution in patients younger than 50 years on the course of central retinal vein occlusion (CRVO) and to compare these results with those of older patients with CRVO. PATIENTS AND METHODS--We performed a prospective study on 35 patients younger than 50 years who were suffering from a central retinal vein occlusion. These patients were all treated by isovolemic hemodilution and compared to a group of older patients with CRVO with the same treatment. RESULTS--About 66% of the younger patients were men compared to only 46% in older patients. At least two cardiovascular risk factors were present in 8.5% of the younger and 54% of the older patients. 16 eyes showed the ischemic, 19 the nonischemic type of CRVO, a similar distribution as in older patients. The course of the disease was more favourable in younger patients, although ocular complications may occur in ischemic CRVO. Isovolemic hemodilution did not change the initial visual acuity of eyes with nonischemic CRVO, but led to an improvement in 56% of the eyes with ischemic CRVO. This means only a minor difference to the course of CRVO in hemodiluted older patients. CONCLUSION--In general, there is no principal difference between the CRVO in younger and older patients, but the course is more favourable in younger patients. On the basis of these findings we recommend isovolemic hemodilution in younger patients with ischemic CRVO.

Combined Modality Therapy↗
PubMed1993

[Effect of pterygium operation on preoperative astigmatism. Prospective study].

High-grade corneal astigmatism is considered to be an indication for pterygium surgery. However, no prospective studies have been carried out to determine whether a pterygium operation really reduces preoperative astigmatism. Therefore, we prospectively examined 23 patients who were operated on for pterygia at the University Eye Clinic in Freiburg in 1991. Pre- and postoperative corneal astigmatism was measured by ophthalmometry or retinoscopy. Preoperative astigmatism after pterygium surgery was reduced or unaltered in 19 patients. In 4 patients, the postoperative astigmatism was increased. The mean preoperative astigmatism was 2.41 D in the horizontal meridian, the postoperative astigmatism 1.29 D. The reduction was statistically significant (P < 0.0001, Wilcoxon test). The higher the preoperative astigmatism, the higher the difference between pre- and postoperative astigmatism (r2 = 0.88, P = 0.0001). Our technique of pterygium surgery (free conjunctival transplant after polishing the cornea, limbus, and sclera) reduces preoperative astigmatism. Thus, high-grade astigmatism can be regarded as an indication for pterygium surgery.

Astigmatism↗
PubMed1991

Orbital squamous cell carcinoma after retinal detachment surgery.

We report on a 76-year-old patient with a squamous cell carcinoma of the left orbit. The tumour had no connection with the conjunctiva but was located at the site of an encircling band which had been inserted 13 years before. A major part of the tumour presented as a well circumscribed solid mass within the extraocular tissues next to the inferior equator, but the exenteration specimen also showed tumour extension within the adjacent choroid. Histological examination showed a well differentiated keratinising squamous cell carcinoma with numerous mitotic figures and many epithelial pearls. A thorough examination in search of a primary carcinoma of the lacrimal gland or the sinus, with invasion into the orbit, or an epithelial neoplasm elsewhere suggestive of metastatic disease into the choroid did not reveal any specific pathological findings. Thus the most probable origin of the tumour seems to be epithelium which had been misplaced during retinal detachment surgery and had subsequently undergone malignant transformation.

Aged↗
PubMed1991

[Chronic lipogranuloma of the eyelids after paranasal sinus operations].

Over a period of about 1 year we observed five patients who developed tumors of their eyelids a few days to 3 weeks after surgery on the paranasal sinuses through the nasal passage. One patient noticed a swelling of his ipsilateral eyelid during an irrigation procedure for the maxillary sinus, which was also followed by endonasal surgery. After surgery each patient developed an ipsilateral periorbital hematoma and subsequently solid indolent tumors of the eyelid without a tendency to regress over a period of 3 to 14 months. Therefore, surgical treatment was necessary. The histological examination showed lipogranulomas with giant cells and many lipid vacuoles of different size. Exploring the origin of these lipids, we performed a magnetic-resonance-spectrum analysis of one tumor sample. We predominantly found signals for linear hydrocarbons, which are the main components in paraffin-liquids. We presume that our patients developed lipogranulomas of their eyelids due to the paraffin introduced into the tissue by the ointment used to tampon the paranasal sinus after endonasal surgery.

Adult↗
PubMed1989

[Arteriovenous malformation of the orbit].

Arteriovenous malformation is a rare vascular disease of the orbit that has to be differentiated from arteriovenous fistulas (e.g., of the carotid sinus), arterial aneurysms, the varices and the angiomas. It develops in the presence of an underlying constitutional maldifferentiation of the vascular bed but usually only becomes manifest in early adulthood. Typical clinical signs are exophthalmos, often with pulsation and thrill; episcleral and conjunctival vascular congestion; secondary glaucoma; and, to varying degrees in the late stage, restricted movement with double images as well as functional losses. The therapeutic measures otherwise routinely applied for such vascular deformities - e.g., surgical excision or, even better, embolization - have to be handled with ease in the orbit, since these vascular convolutions are also supplied in all cases by the ophthalmic artery. Two typical cases are presented to illustrate the clinical picture, diagnosis, differential diagnosis, and treatment possibilities.

Adolescent↗
PubMed1989

Primary malignant melanoma of the orbit arising in a cellular blue naevus.

Primary malignant melanoma of the orbit is a rare clinical entity. We report the clinical course and present the light and electron microscopic findings in a case arising in a cellular blue naevus. While most orbital melanomas are associated with a naevus of Ota, there was no clinically visible abnormal pigmentation in our patient. The possible origin of the tumour cell and its ultrastructural features are discussed.

Adult↗
PubMed1989

[Histopathology of the eye--recent technics].

The histopathology of the eye is especially suitable for demonstrating the necessity and advantages of a close clinicopathological correlation. It should therefore be performed by a clinical ophthalmologist who is especially trained in histopathology. During recent years it has been realized more and more that metabolism and function in a living organism are only possible in relation to intact morphological structures. This led to a "renaissance" of morphology in general and of human histopathology and ophthalmopathology in particular. The workup of ophthalmopathologic specimens includes careful dissection of the globe, its macroscopic examination under the stereomicroscope, photographic documentation of interesting findings, and the application of all modern techniques of histopathology, such as light microscopy, electron microscopy, scanning electron microscopy, freeze-fracture techniques, and immunohistochemistry. The above methods are briefly discussed.

Eye↗