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R Guthoff

Publications and source records attributed to R Guthoff.

At least 19 recordsLinked to original sources
PubMed2006

[In vivo imaging of the conjunctival epithelium using confocal laser scanning microscopy].

BACKGROUND: In various ocular diseases, cytomorphological findings of the ocular surface are an essential component of clinical diagnostics. When evaluating the conjunctival epithelium, minimally invasive acquisition of biomaterial is necessary for lab and technical processing and in vitro histological examination. To examine corneal structures in vivo, confocal laser scanning microscopy is a successful standard method. Our aim was to employ in vivo confocal laser scanning microscopy also for examining the conjunctival epithelium. MATERIAL AND METHOD: Results were analyzed and compared with cytomorphological findings of impression cytology. Accordingly, the basic features of conjunctival in vivo examination using RLSM were described and defined. In vivo images were analyzed and compared with impression cytological slide preparations (n=110) of 23 healthy test persons. Examination was standardized. Finally, the confocal laser scan images were compared to the impression cytological patterns. RESULTS: Due to the distribution of reflectors (pixel brightness), diagnostic analysis of important morphological structures (cell nucleus, cytoplasm, nucleus/plasma relation) of the conjunctiva is possible. Secretory cells of the epithelium (goblet cells) can be easily recognized by their size. Highly reflective pixels depict cell walls or wide intercellular spaces with high contrast. CONCLUSIONS: The in vivo investigation of important anatomical and morphological structures of the conjunctival epithelium is possible using RLSM. The distribution pattern of goblet cell pixel brightness may correlate with various secretion contents or suggest distinct, recognizable, functional conditions (hypo- or hypersecretion).

Conjunctiva↗
PubMed2006

[Postoperative care after glaucoma filtration surgery].

Scarring of the filtering bleb is the main complication after glaucoma filtration surgery. Postoperative care most importantly determines success or failure of the operation. Both, preoperative antiinflammatory treatment and reduction or discontinuation of topical medication have a positive effect on postoperative conjunctival wound healing. After conventional postoperative care only about 40% of patients reach target pressures in the long-term without topical medication. Intensified postoperative care (IPC) increases the success rate by 25% after 5 years. Central to the concept of IPC is a wound modulating therapy which is adapted to the phases of wound healing of the filtering bleb. Evaluation of filtering bleb morphology is a prerequisite for the application of topical steroids and 5-fluorouracil. In addition, dedicated counseling of the patient and close follow-up are mandatory. In order to further increase the success rate of penetrating glaucoma surgery and decrease the side effects of the current antimetabolite therapy more research on wound healing as well as specific therapy to prevent scarring are necessary.

Administration, Topical↗
PubMed2006

[Photodynamic therapy in classic chorioidal neovascularisation in patients with angioid streaks].

BACKGROUND: The development of subfoveal or juxtafoveal choroidal neovascularisation (CNV) secondary to angioid streaks poses a great therapeutic challenge. The relevance of the photodynamic therapy (PDT) with verteporfin is still unclear. We present the functional and anatomic outcome of 5 patients with CNV due to angioid streaks treated by PDT. METHODS: We reviewed 4 eyes with subfoveal and 1 eye with juxtafoveal CNV in angioid streaks of 5 patients (4 male, 1 female) treated by PDT between 2000 and 2005. The age ranged from 20 to 74 years (median 63 years). PDT was performed according to the TAP criteria. Best corrected visual acuity was measured using ETDRS charts. RESULTS: Visual acuity (VA) ranged between 20/63 and 20/32 (median 20/32) at first presentation and between 20/2000 (counting fingers) and 20/20 (median 20/400) at last presentation. Median follow-up time was 13 months with a range of 5 to 45 months. The visual acuity in one patient decreased by 1 line, in 3 patients by more than 6 lines whereas VA of one patient (juxtafoveal CNV) increased by 2 lines. PDT was repeated in 4 patients once because of persistent leakage and in one patient twice. At the end of the follow-up period a fibrous disciform lesion was seen in 4 patients, in one patient subfoveal membranectomy was performed due to a recurrence. CONCLUSIONS: In general, PDT of CNV is less favourable in angioid streaks than in AMD. However, in the natural course final VA is counting fingers. Therefore the good results of individual cases justify the PDT under a critical indication.

Adult↗
PubMed2005

Evaluation of biometric methods for measuring the anterior chamber depth in the non-contact mode.

PURPOSE: High-resolution biometry of the anterior ocular segment is now becoming more and more important against a background of refractive surgery and the evaluation of potentially accommodative lens replacement materials. The aim of this study was a systematic investigation of the currently available non-contact methods for measuring the anterior chamber depth (ACD). METHODS: The ACDs of 50 phakic eyes of 27 patients aged between 19 and 59 years were measured with the IOL-Master (Zeiss), the AC-Master (Zeiss), the Pentacam (Oculus) and slit-lamp pachymetry by Jaeger (Haag-Streit). RESULTS: The median anterior chamber depth in the investigated eyes was 3.63 mm for the IOL-Master (minimum 2.88 mm, maximum 4.22 mm), 3.802 mm for the AC-Master (2.816 mm-4.373 mm), 3.915 mm for the Pentacam (minimum 2.994 mm, maximum 4.614 mm) and 3.75 mm for Jaeger (2.887 mm-4.29 mm). With a probability of error of alpha=0.05 there were no significant differences concerning the ACD between the methods of Jaeger and AC-Master, Jaeger and IOL-Master, or Pentacam and AC-Master (Wilcoxon and Wilcox). The intra-individual variability was +/-5.4 microm for AC-Master, +/-12.7 microm for Pentacam, +/-24.5 microm for IOL-Master and +/-41.2 microm for Jaeger. The maximum method-dependent difference in ACD determination was 285 microm. CONCLUSIONS: All the methods allow non-contact biometry, but the results might differ due to measuring principles inherent to the system, experience of the examiner and compliance of the patient. Partial coherence interferometry with the AC-Master offers the advantage of measurement exactly along the optical axis with the highest reproducibility and patient compliance.

Adult↗
PubMed2005

[Accuracy of the autorefractor power refractor in clinical work--a comparative study].

BACKGROUND: The aim of this prospective study was to investigate accuracy and efficiency of the autorefractometer PowerRefractor compared to established autorefractometers and retinoscopy as standard method. PATIENTS AND METHODS: 150 patients (300 eyes) were examined. Patients were initially (pupil not influenced) analyzed with the Power Refractor (PR (neutral)). After that a examination followed under standardized Cyclopentolat cycloplegia with the Power Refractor (PR (cyclo)), the hand-held Retinomax K-plus (Nikon), the table-top mounted RK-5 (Canon) and retinoscopy. RESULTS: Deviation from retinoscopy (percentage of values with more than 1 dpt difference/maximal deviation): Sphere: PR (neutral): 66.3 %/8.5 dpt; PR (cyclo): 48 %/5 dpt; RK-5: 26.7 %/4.75 dpt; Retinomax K-plus: 6.7 %/1.25 dpt; Cylinder: PR (neutral): 12 %/6.25 dpt; PR (cyclo): 21 %/4.75 dpt; RK-5: 1.3 %/2.75 dpt; Retinomax K-plus: 2.3 %/2.5 dpt; spherical equivalent: PR (neutral): 44.7 %/7.1 dpt; PR (cyclo): 35.3 %/5.4 dpt; RK-5: 9 %/4.5 dpt; Retinomax K-plus: 1.3 %/1.,4 dpt; error of entire refraction: PR (neutral): 62.7 %/7.8 dpt; PR (cyclo): 61.3 %/7.3 dpt; RK-5: 24 %/4,5 dpt; Retinomax K-plus: 14.7 %/3.6 dpt CONCLUSIONS: The best accuracy compared to retinoscopy had Retinomax K-plus followed by RK-5. PowerRefractor had the biggest deviations of the tested devices. PowerRefractor may be a usefull device for screening small children and handicapped people because of the one meter observing distance. For a precise refraction especially in children a retinoscopy under cycloplegic conditions is still necessary.

Adolescent↗
PubMed2004

[Association of malignant tumors of the conjunctiva and HIV infection in Kinshasa (D. R. Congo). First results].

BACKGROUND: Conjunctival carcinomas are tumors especially of the 6th/7th decades. They occur in Germany with a frequency of 1/20,000. For years it has been well known that in Africa the number of malignant tumors of the conjunctiva has been increasing. The reasons for that are not well known. HIV is a possible pathogenetic cofactor. METHOD: A histological examination of 34 specimens was performed in Rostock on conjunctival tumors removed at the Ophthalmologic Department of the University of Kinshasa in 2001. The study included 23 female and 11 male patients aged 20-75 years (mean 42). All patients underwent serological investigation for HIV infection. RESULTS: Of 34 patients 18 were HIV positive. Of the HIV-positive patients, six had a squamous cell carcinoma, seven a CIN (conjunctival intraepithelial neoplasia) I-III, and five a pinguecula. Of the HIV-negative patients, five showed a squamous cell carcinoma, eight a CIN I-III, one a pinguecula, one a sebaceous gland carcinoma, and one a papilloma. The average age of the HIV-positive patients with a squamous cell carcinoma was 41 years compared to the HIV-negative patients with 58 years. CONCLUSIONS: There was no difference in frequency of conjunctival intraepithelial neoplasia between HIV-positive or HIV-negative patients. HIV-positive patients with a squamous cell carcinoma were on average 17 years younger. UV radiation is the main risk factor and HIV infection is a possible carcinogenic cofactor. Investigations on additional viral infections as possible pathogenetic factors and on changed tumor suppressor genes are needed.

AIDS Serodiagnosis↗
PubMed2004

[The methodology and accuracy of MRI-based orbital volume calculations].

OBJECTIVE: The aim of the present work was to establish a method for orbital volume calculation based on MR scanning data for the sake of better radiation hygiene. MATERIALS AND METHODS: The orbital volumes of 35 ophthalmologically healthy children were calculated on the basis of MRI scans. After data transfer to a separate workstation, volumetric analysis was carried out by two independent radiologists using semi-automated software. The accuracy of the calculated values was compared with orbital volumes measured by anatomic preparations and given in studies by various authors. RESULTS: Volume calculation was possible in all patients using MRI data. There is an acceptable agreement with the presented anatomic facts and the measured values of Bentheley. In the Wilcoxon test there was not a big difference between the courses of the values (p = 0.507). CONCLUSION: Even though we can obtain a better image of the bizarre structure of the bony orbits with CT, MR-based volumetry of the orbit is a reliable method and is not burdened by radiation exposure. It can thus be an important condition for the planning and the controlling of modern therapeutic concepts in treating anophthalmos and microphthalmos.

Aging↗
PubMed2004

[Bilateral AION after the combined therapy of hepatitis C with PEG-interferon alpha2B and ribavirin].

INTRODUCTION: Chronic hepatitis C-therapy is limited to the combined use of PEG-ylated interferons and ribavirin. Side effects of this therapy include retinal changes that manifest with bleeding, cotton wool spots and/or thrombosis. PATIENT: A 51-year-old man presented with a sudden decrease of visual acuity. Chronic hepatitis C was known for the duration of 6 months and treated for 3 months with a combined therapy of PEG-interferon alpha2B and ribavirin. A sudden visual loss occurred in the right eye and bilateral visual field defects were detected. Ophthalmoscopic examination revealed bilateral papilloedema. After withdrawal of PEG-interferon alpha2B and ribavirin, a standard haemodilution therapy was started without functional improvement. After papilloedema regression, a beginning secondary atrophy of the optic nerve was diagnosed bilaterally. Vision did not improve. CONCLUSION: The ocular side effects of combined hepatitis C therapy with PEG-interferon alpha2B and ribavirin range from mild retinal changes to severely impaired vision. Treatment should be carried out in co-operation with an ophthalmologist. With respect to the uncertain effectiveness of hepatitis C therapy with interferon alpha2B and ribavirin, therapy should be stopped as soon as severe ophthalmological complications occur.

Antiviral Agents↗
PubMed2004

[Orbital volume in congenital clinical anophthalmos].

INTRODUCTION: The purpose of this study is to report orbital volume measurement results in patients with congenital clinical anophthalmia before and after therapy and to compare them with normal values. PATIENTS AND METHOD: Normal values were obtained from 35 healthy children (22 boys, 13 girls; aged 3 month to 7 years) in whom MRI was done for non-ophthalmological reasons. 18 patients with congenital anophthalmos could be included, 9 with bilateral, 8 with unilateral disease and 1 microphthalmos. 6 of them had MRI follow-up (more than one examination). RESULTS: Orbital volume at birth is 7 ml and it increases with age: Orbital volume = 7.701 x age (month) (0.2484) ml. It is around 14.2 ml at the age 1 year, 17 ml with 2 years and reaches 23 ml with 7 years. In unilateral clinical anophthalmos orbital volume is 35 to 58 % compared with the healthy side and 31 to 65 % compared with the normal values. In bilateral cases the volume is 43 to 70 % of the normal value. During treatment it develops in parallel to the normal values. CONCLUSIONS: The normal values measured by our group are in accordance with the only published study by Bentley . MRI orbital volumetry is a reliable method without using radiation. It allows us to quantify the bony asymmetry and is suitable for therapy control when using orbital expanders. The congenital missing eye might be the most important reason why the orbit does not develop in the normal way to a normal size. Self-inflating high, hydrophilic hydrogel expanders do not seem to be able to compensate this, in spite of the fact that they work very well to prepare the socket for a prosthesis.

Aging↗
PubMed2004

[Strabismus surgery in Grave's disease--dose-effect relationships and functional results].

BACKGROUND: Strabismus in thyroid ophthalmopathy is based on a loss of the contractility and distensibility of the external ocular muscles. Different therapeutic approaches are available, such as recession after pre-. or intraoperative measurement, adjustable sutures, antagonist resection, or contralateral synergist faden-operation. PATIENTS AND METHODS: 26 patients with strabismus in thyroid ophthalmopathy were operated between 2000 and 2003. All patients were examined preoperatively, then 1 day and 3 - 6 months (maximum 36 months) postoperatively. Before proceeding with surgery, we waited at least 6 months after stabilization of ocular alignment and normalization of thyroid chemistry. RESULTS: Preoperative vertical deviation was 10-44 PD (mean 22), 3 months postoperatively it was 2-10 PD (mean 1.5). Recession of the fibrotic muscle leads to reproducible results: 3.98 +/- 0.52 PD vertical deviation/mm for the inferior rectus. In the case of a large preoperative deviation a correction should be expected, which might not be sufficient in the first few days or weeks; a second operation should not be carried out before 3 months. 7 patients were operated twice, 1 patient need three operations. 4 patients (preop. 0) achieved no double vision at all; 15 patients (preop. 1) had no double vision in the primary and reading positions; 3 patients (preop. 0) had no double vision with a maximum of 5 PD; 1 patient (preop. 7) had double vision in the primary or reading position even with prisms; and 2 patients (preop. 17) had double vision in every position. CONCLUSIONS: We advocate that recession of the restricted inferior or internal rectus muscle is precise, safe and effective in patients with thyroid ophthalmopathy. The recessed muscle should be fixed directly at the sclera to avoid late over-correction through a slipped muscle. The success rate in terms of binocular single vision was 76 % and 88 % with prisms added.

Adult↗
PubMed2003

[Gene expression in keratoconus. Initial results using DNA microarrays].

INTRODUCTION: Keratoconus is a non-inflammatory ocular disease characterised by conical deformation, progressive thinning and scarring of the central cornea. Despite intensive investigations, the exact cause of the disease still remains unclear. Clinical studies provide strong indications of a major genetic role in the aetiology. We set out to examine the involvement in the manifestation of keratoconus of any of the 5,600 gene specificities available on the Affymetrix GeneChip HuGeneFL. METHODS: After examination of two corneas they were stored in RNAlater, RNA was extracted and hybridised on the chips. Using a combination of dyes it was possible to read the chips with laser detection and to visualise the gene expression pattern. RESULTS: We found an upregulation of collagens, versican, metalloproteinases and cell adhesion proteins. A downregulation was observed for TIGR protein, cytokeratins, eyes absent homologue (Eab1) and the proteins for radical treatment selenoprotein P and monooxygenase. CONCLUSIONS: Our results indicate that keratoconus is a process in which repair and scar-formation mechanisms operate at the same time. As candidate genes for this mechanism, collagen IV and related proteoglycans were favoured.

Cicatrix↗
PubMed2003

[Muscle pedunculated scleral flaps. A microsurgical modification to improve prosthesis motility].

Orbital implants following enucleation are able beyond all doubt to compensate volume adequately and improve artificial eye motility. In recent decades progress has been made concerning implant material. Nevertheless, in most designs wrapping with homoplastic or alloplastic materials is advocated. In this report a microsurgical concept is presented to avoid wrapping material and at the same time to improve prosthesis motility in a hydroxyapatite-silicon implant. In a retrospective study two groups of patients (15 individuals each) were compared concerning prosthesis motility 6 months after surgery. In group 1 the horizontal and vertical eye muscles were sutured cross-wise in front of the implant (as done since the introduction of this type in 1989). In group 2 autologous muscle pedunculated scleral flaps were dissected microsurgically and used to cover the anterior part of the porous hydroxyapatite component of the implant. There was a highly significant better prosthesis motility and so far no complications concerning implant coverage in this second group. The authors consider the use of muscle pedunculated sclera to be a modification to improve the cosmetic outcome which may also reduce the postoperative complication rate in enucleation surgery.

Equipment Failure Analysis↗
PubMed2003

[How can artificial eye motility be improved? The influence of fornix configuration and tissue thickness in front of hydroxyapatite-silicon implants in 66 patients].

Porous hydroxyapatite of various origins has proven to be a suitable material for orbital volume replacement. Its biocompatibility surpasses all other options. The transmitted motility to the artificial eye has nevertheless, not always been to the full satisfaction of patients, oculists and ophthalmologists. Our study has shown a strong correlation between the depth of the superior and interior fornices as well as the thickness of tissue material covering the implant anterior surface.

Adult↗
PubMed2003

[Retinal diseases with primary pulmonary hypertension].

BACKGROUND: Primary pulmonary hypertension (PPH) is a rare but fatal disease that results in right heart failure from idiopathic occlusion of the pulmonary arteries. Patients develop stagnation of venous pressure. PPH occurs most commonly in young and middle-aged women and the mean survival time from onset of symptoms is 2-3 years. The aetiology of PPH is unknown, although familial occurrence of the disease suggests a genetic predisposition. Pulmonary transplantation is reserved for patients who fail medical therapy. Pathophysiologically, PPH is a functional and structural alteration of the pulmonary blood vessels. METHODS: The authors retrospectively reviewed the clinical records of three patients (mean age 34 years) diagnosed with PPH and retinal diseases. RESULTS: All three patients developed central retinal vein occlusion (CRVO). One patient developed a neovascular glaucoma and on the other eye a serous retinal detachment with uveal effusion. A few months after the central vein obstruction was diagnosed two patients died as a result of PPH. CONCLUSIONS: The elevated venous pressure found in PPH is responsible for decreased choroidal perfusion and reduced venous blood outflow from the eye. This would explain the clinical findings of serous retinal detachment and central retinal vein occlusion in these patients.

Adult↗
PubMed2003

Herpes zoster guideline of the German Dermatology Society (DDG).

Varicella zoster virus (VZV) causes varicella (chickenpox), remains dormant in dorsal root and cranial nerve ganglia and can be reactivated as a consequence of declining VZV-specific cellular immunity leading to herpes zoster (shingles). Patients older than 50 years of age affected by herpes zoster may suffer a significant decrease of quality of life. These patients and immunocompromised individuals are at increased risks for severe complications, involving the eye, the peripheral and the central nervous system (prolonged pain, postherpetic neuralgia). Such complications occur with and without cutaneous symptoms. The German Dermatology Society (DDG) has released guidelines in order to guarantee updated management to anyone affected by herpes zoster. Diagnosis is primarily clinical. The gold standard of laboratory diagnosis comprises PCR and direct identification of VZV in cell cultures. Detection of IgM- and IgA-anti VZV antibodies may be helpful in immunocompromised patients. Therapy has become very effective in the last years. Systemic antiviral therapy is able to shorten the healing process of acute herpes zoster, to prevent or to alleviate pain and other acute and chronic complications, particularly, when given within 48 h to a maximum of 72 h after onset of the rash. Systemic antiviral therapy is urgently indicated in patients beyond the age of 50 years and in patients at any age with herpes zoster in the head and neck area, especially in patients with zoster ophthalmicus. Further urgent indications are severe herpes zoster on the trunk and on the extremities, herpes zoster in immunosuppressed patients and in patients with severe atopic dermatitis and severe ekzema. Only relative indications for antiviral therapy exist in patients younger than 50 years with zoster on the trunk and on the extremities. In Germany acyclovir, valacyclovir, famciclovir and brivudin are approved for the systemic antiviral treatment of herpes zoster. These compounds are all well tolerated by the patients and do not differ with regard to efficacy and safety. Brivudin has a markedly higher anti-VZV potency than oral acyclovir, valacyclovir and famciclovir and thus offers a simpler dosing regimen. It must be given only once daily during 7 days in comparison to three and five times dosing per day of valacyclovir, famciclovir and acyclovir, respectively. Brivudin is an antiviral agent with no nephrotoxic properties, which is an advantage when compared to acyclovir. The most important aim of therapy of herpes zoster is to achieve painlessness. Appropriately dosed analgesics in combination with a neuroactive agent (i.e. amitriptylin) are very helpful when given together with antiviral therapy. The additive therapy with corticosteroids may shorten the degree and duration of acute zoster pain, but has no essential effect on the development of postherpetic neuralgia, which is a very difficult condition to treat. Thus early presentation to a pain therapist is recommended in specific cases.

Adolescent↗