Scanning laser polarimetry in myopic and hyperopic subjects

Purpose To investigate the effect of refraction error and axial length on retinal nerve fiber layer (RNFL) measurements as obtained by scanning laser polarimetry (SLP).Methods Besides ophthalmological standard examination (refractive error, keratometry, visual acuity, slit-lamp examination, applanation tonometry, funduscopy), perimetry, axial length measurement by means of ultrasound, and SLP were performed. Seventy-five myopic eyes (between –0.75 D and –8.5 D), 24 hyperopic eyes (0.75 D–6.5 D) and 40 emmetropic eyes were investigated. SLP parameters were compared in the different groups.Results The statistical analysis of the absolute thickness values of SLP revealed highly significant (P<0.01) reductions in average thickness, ellipse average, superior average, inferior average, and superior integral in both myopic and hyperopic eyes in comparison with the emmetropic control eyes. The amount of reduction was between 12.9% (inferior average; myopia) and 30.2% (superior integral; hyperopia). There were no significant differences between myopes and hyperopes. A significant linear correlation for many of the SLP parameters with the refractive error (spherical equivalent) but not with axial length was found in both the hyperopic and the myopic group.Conclusions Despite a wide interindividual range, SLP measurement values decrease with increasing myopia and hyperopia. In clinical practice, such reduced RNFL thickness values should be viewed with the necessary caution and additional polarimetric signs for glaucomatous damage should be taken into consideration.     

von Willebrand Disease : A Clinico-haematological Spectrum

Background

Bleeding disorders are commonly seen in clinical practice. von Willebrand Disease (vWD), is the commonest and yet a profoundly under diagnosed cause, having a wide spectrum of clinical presentation. Of its three types, type 1 vWD (70% of the total vWD cases) has the mildest and a highly variable clinical and laboratory presentation.

Methods

A series of ten cases of vWD were comprehensively evaluated using recommended diagnostic parameters and therapeutic interventions.

Results

All major types of vWD were represented. A female preponderance, with primary presentation in the form of muco-cutaneous bleeds was observed. A positive history of consanguineous parental marriage and family history of bleeding disorder was elicited in two and three patients respectively. Nine patients were found to be anemic and thrombocytopenia was present in only one. Bleeding time by modified template (SIMPLATE) method, along with activated partial thromboplastin time (APTT) was increased in all ten cases and of these, nine had low factor VIII: C levels. Ristocetin induced platelet aggregation studies were abnormal in all the five cases it was performed. vWF:RCo activity determined in one individual was shown to be low. vWF:Ag assay was done in four cases revealing a near complete absence of von Willebrand factor antigen in one and mildly decreased levels in the other three. vWF multimer assay was advised in three cases. DDAVP, plasma derived vWF, blood products and local antifibrinolytics were used as primary modalities of treatment

Conclusion

Thus, strong clinical suspicion, thorough clinical evaluation and judicious use of investigations including repeated investigations at different times are needed for making a diagnosis of vWD.Key Words: Bleeding disorders, von Willebrand Disease     

Laser scanning topography and polarimetry with implantation of intraocular lenses before and after cataract surgery]

BACKGROUND: In the last years, scanning laser measurements were established in glaucoma diagnostics. Techniques of special interest are scanning laser topometry (SLT) for exact measurements of the optic disc and its cup and scanning laser polarimetry (SLP) for precise assessment of the retinal nerve fiber layer thickness. As glaucoma patients often suffer from a cataract, too, and a trabeculectomy additionally favors the advance of lens opacities, in the follow up of glaucoma patients cataract surgery is often necessary. PATIENTS AND METHODS: The influence of cataract surgery in phacotechnique with intraocular lens implantation (31 PMMA-IOLs, Pharmacia/Upjohn, model 811 B, and 25 HEMA/MMA-IOLs, Technomed, Memory Lens) on SLT and SLP was evaluated before and 3 to 4 weeks after cataract surgery in 56 eyes of otherwise healthy patients. Lens opacities were classified according to LOCS III. For SLT, we applied a TopSS, and for SLP a Nerve Fiber Analyzer II and a GDx (LDT, USA). RESULTS: Our results show that SLT and SLP are mostly performable at lens opacities with visual acuity reductions down to 0.16. In SLT, we usually found no big differences in the assessed parameters before and after cataract surgeries with IOL implantation. Standard deviations between three single measurements were mostly smaller postop. In SLP, nerve fiber layer patterns were very similar before and after cataract surgeries with IOL implantation whereas total nerve fiber layer thickness values postoperatively were slightly higher. CONCLUSIONS: Our results indicate that cataract surgeries with IOL-implantation have only mild influence on SLT and SLP. These findings seem to be of clinical interest especially in the follow up of glaucoma patients.     

Treatment of HSV-1 stromal keratitis with topical cyclosporin A: a pilot study

· Background: In stromal keratitis induced by herpes simplex virus (HSV) the host’s immune response contributes to corneal scarring and neovascularization. The purpose of this study was to analyze the efficacy of topically applied cyclosporin A (CsA) in patients with HSV keratitis. · Methods: The authors performed a prospective pilot study in patients with HSV stromal keratitis (n=18). Eyes were treated with CsA eyedrops and acyclovir ointment. The drugs were tapered off gradually. Visual acuity, slit-lamp appearance, intraocular pressure and corneal sensitivity were evaluated monthly (follow-up 5.2±0.28 months, mean±SEM. · Results: Keratitis resolved with CsA treatment in 10 of 14 patients with non-necrotizing keratitis and in 2 of 4 with necrotizing keratitis. As CsA was used topically, the corticosteroids could be withdrawn in all patients with non-necrotizing keratitis and in 1 of 3 with necrotizing keratitis. Under CsA therapy, persistent or progressive inflammation was noted in 6 of the 18 patients. These 6 patients with keratitis improved only with combined CsA/corticosteroids. Corneal ulcers healed in 4 patients with topical CsA, and corneal neovascularization improved in a further 8. Except for toxic epitheliopathy, no further CsA complications were noted. · Conclusions: The findings in this pilot study suggest that HSV stromal keratitis can be treated successfully with CsA eyedrops, especially in non-necrotizing disease. CsA may be particularly helpful in the presence of steroid glaucoma, herpetic corneal ulcers, and to taper off topical corticosteroids. Additional use of acyclovir may aid in suppressing the recurrence of epithelial HSV keratitis. A randomized study should be performed to evaluate the role of topical CsA in more detail. Received: 23 April 1998 Revised version received: 12 August 1998 Accepted: 14 September 1998     

Fehlstellungen der Hüfte

Monatsschrift Kinderheilkunde - Fehlstellungen der Hüfte sind bei Kindern und Jugendlichen gut an einem hinkenden Gang, an der Rumpfasymmetrie im Stand sowie an einem seitendifferenten aktiven...     

Cystic teratoma of the orbit

Teratomas are rare cystic tumors of the orbit which lead to excessive congenital exophthalmos. They increase rapidly in size after birth and therefore require immediate surgical treatment. Initial puncture of the cyst under sonographic control prevents progressive mechanical damage to the globe and the optic nerve, providing sufficient time for the preoperative measures required prior to final surgical removal. The characteristic clinical features make it easy to identify a teratoma provided it has been taken into consideration in the differential diagnosis. It is shown with reference to one of the authors' own cases that a good functional result is possible after removal of the encapsulated tumor with preservation of the globe, even when the eye has been excessively displaced by the tumor.     

Digital subtraction angiography system evaluation with phantoms

Advances in digital subtraction angiography imaging demonstrate the need for critical evaluation of the performance of digital subtraction equipment. The design of a phantom set for noninvasive assessment of the imaging quality of digital subtraction equipment is described; components include a remotely controlled transport system and individual patterns to evaluate the contrast and detail properties of the image intensifier, low-contrast sensitivity and resolution of the system, geometric distortion of image, linearity, mechanical and electronic stability of equipment, and effects of bone and bowel gas on iodine perception. The performance of an add-on digital radiographic system is presented, along with radiation exposure levels at the image intensifier for a range of radiographic techniques.