Loay Daas

Confocal microscopy in acanthamoeba keratitis as an early relapse-marker

Acanthameoba keratitis is a serious ophthalmological condition with a potentially vision‐threatening prognosis. Early diagnosis and recognition of relapse, and the detection of persistent Acanthamoeba cysts, are essential for informing the prognosis and managing the condition. We suggest the use of in vivo confocal microscopy not only to identify the early signs of relapse after keratoplasty in patients with Acanthamoeba keratitis, but also as an additional follow‐up tool after antimicrobial crosslinking. This study shows that in vivo confocal microscopy is, in experienced hands, a quick and reliable diagnostic tool. Clin. Anat. 31:60–63, 2018.

Anatomy-Based DMEK-Wetlab in Homburg/Saar – Novel aspects of donor preparation and host maneuvers to teach Descemet Membrane Endothelial Keratoplasty

Use of Descemet Membrane Endothelial Keratoplasty (DMEK) has been limited because of problems with donor preparation, i.e. tearing of the Descemet membrane and difficulties in unfolding the Endothelium‐Descemet‐Membrane‐Layer (EDML) in the anterior chamber (AC). The purpose of this work was to describe a novel approach to teaching anatomy‐based donor and recipient preparation in a DMEK‐Wetlab. We teach successful mono‐manual donor preparation of human corneas in organ culture not suitable for transplantation, including peripheral markers for orientation. We also teach safe recipient preparation in a freshly‐enucleated pig eye in organ culture preservation medium for atraumatic introduction of the EDML roll into the AC, reliable orientation of the EDML during surgery, and stepwise unfolding within the AC. Twenty‐two candidates in the 1. Homburg Cornea Curriculum HCC 2015 who practiced both preparations using three human donor corneas and three pig eyes assessed the procedure as follows: (1) overall grade of the Wetlab 1.4 (median 1, range 1 to 2 ‐ on a scale from 1 (excellent) to 6 (terrible); (2) most participants and tutors stated that the Wetlab is most effective for colleagues who have some previous experience with corneal microsurgery. Our novel anatomy‐based approach to simulating donor preparation and graft implantation for DMEK seems to meet the expectations and requirements of colleagues with previous experience in corneal microsurgery and will help to reduce the rate of complications for incipient DMEK surgeons in the future. Clin. Anat. 31:16–27, 2018.

Intrakorneale Ringsegmente bei Keratektasien – Zwischenergebnisse und potenzielle Komplikationen

BACKGROUND AND PURPOSE Implantation of intracorneal ring segments (ICRS) using a femtosecond laser is a minimally invasive procedure which represents a reliable option to widen the spectrum of the stage-related therapy of keratoconus in patients with contact lens intolerance, or with post-LASIK-keratectasia or pellucide marginale degeneration (PMD). METHODS From August 2011 to September 2015, 84 eyes of 69 patients were implanted with ICRS. 74 eyes were implanted with INTACS-SK (Intacs, Addition Technology, Inc.), and 10 eyes were implanted with KeraRing SI6 (Mediaphacos Ltda.). The indication is taken in the presence of a clear central cornea and the patients had to fulfill the corneal diagnostic tests required for implantation. Tunnel creation should nowadays only be carried out by femtosecond laser, in order to avoid intra- and postoperative complications. RESULTS Three months after surgery, the INTACS-SK group showed an increase in uncorrected distance visual acuity (logMAR) from 0.99 ± 0.35 to 0.29 ± 0.17. The KeraRing SI6 group showed an increase in uncorrected distance visual acuity (logMAR) from 0.93 ± 0.4 to 0.41 ± 0.34. The keratometric values were reduced in both groups. CONCLUSION Uncorrected and corrected distance visual acuity can be improved by implantation of the ICRS. Progression of ectasia seems to be retarded. Consistent follow-up visits at close intervals are necessary to identify complications at an early stage. However, larger case series and a longer postoperative observation period are required. Complications after ICRS implantation are rare, due to strict patient selection and modern surgical techniques.

Acanthamoeba keratitis – Clinical signs, differential diagnosis and treatment

Purpose To summarize actual literature data on clinical signs, differential diagnosis, and treatment of acanthamoeba keratitis. Methods Review of literature. Results Clinical signs of acanthamoeba keratitis are in early stages grey-dirty epithelium, pseudodendritiformic epitheliopathy, perineuritis, multifocal stromal infiltrates, ring infiltrate and in later stages scleritis, iris atrophy, anterior synechiae, secondary glaucoma, mature cataract, and chorioretinitis. As conservative treatment, we use up to one year triple-topical therapy (polyhexamethylene-biguanide, propamidine-isethionate, neomycin). In therapy resistant cases, surgical treatment options such as corneal cryotherapy, amniotic membrane transplantation, riboflavin-UVA cross-linking, and penetrating keratoplasty are applied. Conclusion With early diagnosis and conservative or surgical treatment, acanthamoeba keratitis heals in most cases.

Ocular changes in nephropathic cystinosis: The course of the gold-dust

PurposeCystinosis is an autosomal recessive inherited lysosomal storage disease with an incidence of 1:100.000 up to 1:200.000 caused by a gene mutation of a lysosomal transport protein resulting in deposition of cystine in lysosomes in all cells and tissues. In the cornea, crystalline, gold-dust deposition of cystine leads to visual impairment, recurrent erosions, photophobia, epiphora and blepharospasmus. Standard therapy is topical and systemic application of cysteamine which may resolve the accumulated cystine crystals.Patient and methodsThis is a case report of a thirty-one-year-old patient who already underwent renal transplantation because of nephropathic cystinosis. Visual impairment by cystine crystal deposition was aggravated by a central avascular pannus formation in his right eye. Penetrating keratoplasty was performed in intention to improve the patient’s visual acuity and life quality.ResultsAfter penetrating keratoplasty in the right eye, there was only a slight visual improvement. OCT scans of the macula revealed intraretinal cystine crystals and a cystoid macular edema, which was treated with a bevacizumab injection. Transmission electron microscopy of the excised cornea revealed spiky intracorneal inclusions and confocal in vivo microscopy of the left eye allowed detailed visualization of the cystine crystal deposition.ConclusionsThere is a variability of ocular manifestations of nephropathic cystinosis. Ophthalmologists have a central role in the early diagnosis of cystinosis as mostly the first manifestation are cystine crystals in the cornea. Penetrating keratoplasty may be one of the therapeutical options. Nevertheless, the patient has to be informed about the limited prognosis because of the persisting underlying disease.

Tenonplasty for closing defects during sclerocorneal surgery – a brief review of its anatomy and clinical applications

To provide insight into the clinical anatomy of Tenons capsule and to describe a technique to manage sclerocorneal defects using autologous Tenons tissue. A thin layer of Tenons capsule harvested from the patients own eye is used to seal the defect and act as a scaffold. The Tenons flap is spread over the defect and held in place by Vicryl sutures. A bandage contact lens is then placed on the eye. Tenons capsule is composed of thick fibrous tissue with smooth muscle fibers and a thin posterior capsule of orbital fat. It is rich in fibroblasts, which can accelerate wound healing and eventually lead to robust scarring without risk of immunogenicity and without cost. Tenonplasty uses easily‐available autologous Tenons tissue in patients with sclerocorneal defects to preserve globe morphology. The technique is a feasible alternative not limited by the availability of graft tissue. Clin. Anat. 31:72–76, 2018.

Fertőzéses keratitisek diagnosztikája és kezelése

Absztrakt: Munkankban irodalmi adatok es nehany sajat eset bemutatasan keresztul foglaljuk ossze a fertőzeses keratitisek aktualis javasolt diagnosztikajat es kezeleset. Bakterialis, herpeszes, gombas, valamint Acanthamoeba-keratitissel talalkozunk a leggyakrabban a klinikai gyakorlatban. A diagnosztikaban hasznalatos reslampas vizsgalat mellett vegezzuk meg a szaruhartya erzekenysegenek vizsgalatat, in vivo konfokalis mikroszkopiat, polimeraz lancreakciot (PCR), in vitro tenyesztest, valamint a szaruhartyaminta szovettani elemzeset. Konzervativ kezeleskent primeren lokalis moxifloxacint vagy cefazolint erősitett tobramycinnel vagy gentamycinnel alkalmazunk bakterialis, lokalis (esetenkent szisztemas), virusellenes szert szukseg szerint kortikoszteroidos cseppel kombinalva herpeszes, lokalis voriconazolt vagy amphotericin-B-t gombas, valamint harmas terapiat (diamidin, biguanid es antibiotikum) Acanthamoeba-keratitisben. Korai diagnozis felallitasaval es a megfelelő konzervativ kezeles mellett a fertőzese...