Evaluation of colour vision impairment during acute hypobaric hypoxia in aviation medicine: a randomized controlled trial

The digitization of aircraft cockpits places high demands on the colour vision of pilots. The present study investigates colour vision changes upon acute exposure to hypobaric hypoxia. The digital Waggoner Computerized Color Vision Test and the Waggoner D-15 were performed by 54 healthy volunteers in a decompression chamber. Respective altitude levels were sea level, 10,000 or 15,000 ft for exposure periods of 15 and 60 min, respectively. As for 60 min of exposure a significant decrease in colour perception was found between subjects at 15,000 ft as compared to the control group as well as between subjects at 15,000 ft as compared to subjects at 10,000 ft. No significant difference was found in the comparison within the 15,000 ft groups across time points pre-, peri-, and post-exposure. Thus, pilots appear to experience only minor colour vision impairment up to an exposure altitude of 15,000 ft over 60 min of exposure.

[Therapeutic management of a kissing nevus of the eyelid]

Congenital divided melanocytic nevi of the upper and lower eyelid are rare pigmented changes of the eyelids. These processes are also known as "kissing nevi," "panda nevi," and "split ocular nevi," and were first described by Fuchs in 1919. About 120 cases have been described in the literature so far. Congenital melanocytic nevi are either present at birth (small nevi are already found in about 1% of neonates) or manifest predominantly during the first decade of life. These rare melanocytic changes of the eyelids should be controlled regularly, as malignant transformation can occur. The actual incidence of malignant transformation is highly variable in the literature, ranging from 2 to 40% depending on the duration of follow-up, with an average of 14% for the whole lifetime. Moreover, nevi of the eyelids may be considered cosmetically disturbing and cause functional problems. Therapeutic removal (dermabrasion, cryotherapy, laser therapy, and surgical excision with ophthalmoplastic reconstruction) is rarely medically indicated due to the low risk of malignant transformation. Removal can be performed in cases of secondary amblyopia in ptosis, compression of the lacrimal point, epiphora, or cosmetic desire. Treatment becomes necessary not only in case of suspicious manifestation or impairment of eyelid function, but it also helps to avoid possible bullying at school among children and is recommended at age 4 to 6 (before school age).

Surgical excision of eyelid tumors and subsequent ophthalmoplastic reconstruction

In recent years new modern therapeutic concepts have been developed in the treatment of malignant eyelid tumors; however, surgical restoration remains an important component of the therapeutic options addressed, which include microsurgical tumor excision into healthy tissue and subsequent coverage of the defects. An ophthalmic surgeon experienced in oculoplastic surgery is responsible for the recognition and evaluation of the existing alterations and planning a procedure together with the patient that meets the patient's expectations. The planning of surgery must always be individualized and fit the initial findings. Depending on the defect size and localization, different coverage strategies are available to the surgeon. To ensure successful reconstruction, every surgeon should master a wide range of reconstructive techniques.

Diagnosis and treatment of malignant eyelid tumors

BACKGROUND

Malignant tumors of the eyelid are much less frequent than benign eyelid alterations. These are frequently incidental findings without symptoms which are often overlooked or misinterpreted by patients.

OBJECTIVE

This article gives an overview of clinical aspects, diagnostics and treatment of the five most common malignant eyelid tumors and exemplarily explains the essential principles of evidence-based treatment of malignant eyelid tumors.

METHODS

This narrative review was prepared based on a selective literature search. The depiction of the treatment of eyelid tumors is supported by illustrations of clinical cases.

RESULTS

The medical history and inspection provide initial indications of malignancy. Every eyelid change suspected of being malignant should be examined histologically to confirm a diagnosis. By far the most common malignant eyelid tumor in Europe is basal cell carcinoma, which metastasizes only in exceptional cases. Squamous cell carcinomas, sebaceous adenocarcinomas, melanomas and Merkel cell carcinomas occur much less frequently. In these cases, potential metastasis in particular must be considered when making the diagnosis and staging has to be initiated. Surgical excision into healthy tissue with tumor-free margins is the gold standard for malignant eyelid tumors. Non-surgical adjuvant or neoadjuvant forms of evidence-based treatment can be initiated based on the individual case to minimize the risk of recurrence and metastasis.

CONCLUSION

It is essential to recognize eyelid changes at an early stage, to classify them correctly and to initiate the appropriate treatment. The interaction between the general condition and the personal needs of a patient as well as state of the art medicine are the keys to a good personalized treatment.

[Surgical excision of eyelid tumors and subsequent ophthalmoplastic reconstruction]

In recent years new modern therapeutic concepts have been developed in the treatment of malignant eyelid tumors; however, surgical restoration remains an important component of the therapeutic options addressed, which include microsurgical tumor excision into healthy tissue and subsequent coverage of the defects. An ophthalmic surgeon experienced in oculoplastic surgery is responsible for the recognition and evaluation of the existing alterations and planning a procedure together with the patient that meets the patient's expectations. The planning of surgery must always be individualized and fit the initial findings. Depending on the defect size and localization, different coverage strategies are available to the surgeon. To ensure successful reconstruction, every surgeon should master a wide range of reconstructive techniques.

[Diagnosis and treatment of benign eyelid tumors]

BACKGROUND

Benign tumors of the eyelids are frequent entities. They are often cause for cosmetic concern or can lead to irritation of the ocular surface. The differentiation from premalignant or malignant eyelid tumors is particularly important. In most cases this can be done clinically; however, in some cases histological evaluation is warranted.

OBJECTIVE

The aim of this article is to characterize the most important benign tumors of the eyelid and to ascertain when a histological examination is necessary. Furthermore, fundamental treatment procedures are discussed.

METHODS

This narrative review was prepared based on a selective literature search. The characteristics of some eyelid tumors are underlined with illustrations from clinical cases.

RESULTS

Most benign eyelid tumors are treated because of cosmetic or functional concerns. Some of them, including actinic keratosis, keratoacanthoma, cutaneous horn, trichofolliculoma, resemble malignant lid tumors or precancerous lesions and are thus excised in oder to obtain a diagnosis. Dermoid cysts can cause complications and congenital melanocytic naevi can exhibit malignant transformation and may need treatment. Inflammatory tumors can be treated conservatively in most cases but might require surgery in certain cases. Systemic associations exist with some of the benign lid tumors and should not be overlooked as they can be crucial for overall patient morbidity.

CONCLUSION

Benign tumors of the eyelids are frequent and can be found at any age depending on the diagnosis. This article describes the lesions most commonly encountered in the clinical routine and helps at making a plan for further management.

Retrospective analysis of OCT parameters after intravitreal anti-VEGF inhibitors in neovascular AMD patients in a real-world setting

PURPOSE

The aim of the present study was to evaluate changes of best corrected visual acuity (BCVA), retinal nerve fiber layer thickness (RNFL), total macular volume (TMV), intraocular pressure (IOP) and central retinal thickness (CRT) after intravitreal injection of ranibizumab, bevacizumab and aflibercept in patients with neovascular age-related macular degeneration (nAMD) in a clinical real world setting.

METHODS

In a retrospective clinical study design, 120 patients (80 women and 40 men) were analyzed after being diagnosed with nAMD within 8 years (2010-2018). Every patient received at least 6 anti-VEGF injections in a Pro-Re-Nata or Treat-and-Extend regimen. OCT parameters (RNFL, TMV, CRT) and visual acuity (BCVA) were assessed at first diagnosis, at treatment day and during the course.

RESULTS

Intraretinal fluid was reduced significantly in a magnitude of 88-64 µm (CRT) and 0.75-0.55 mm³ (TMV). Apart from a significant reduction immediately after the therapy start (post-3 injections) with ranibizumab (- 1.4 µm, p = 0.03), RNFL thickness remained constant. A slight improvement in visual acuity of 0.06 logMAR could initially be observed. If further injections were required, only stabilization was achieved compared to baseline visual acuity.

CONCLUSION

The changes of OCT parameters CRT, TMV, and RNFL as well as the stabilization of functional results (BCVA) as illustrated in this study comparing effects of different anti-VEGF-agents provide evidence for the transferability of former results to a clinical real-world setting.

[Clinical procedures for intraocular lymphomas]

BACKGROUND

The classification of intraocular lymphomas is based on their anatomical location. They are divided into uveal lymphomas with involvement of the choroid, ciliary body or iris and vitreoretinal lymphomas with isolated or combined involvement of the vitreous body and/or retina. Over the last decades it has become increasingly possible to work out the clinical and pathobiological features of the various subtypes, thereby reducing the diagnostic hurdles and creating improved treatment options.

OBJECTIVE

A summary of the various types of intraocular lymphoma in terms of clinical features, diagnostics, treatment and prognosis is given as well as recommendations for follow-up care.

METHODS

A selective literature search was carried out on the subject of intraocular lymphomas using PubMed and Google Scholar.

RESULTS

Intraocular lymphomas affect different structures, so that the symptoms can also be very different. The diagnostic spectrum ranges from typical ocular examination methods to sample biopsies with subsequent cytological, histological and molecular pathological processing. The treatment pillars available are percutaneous irradiation and intravitreal drug administration as local treatment and systemic treatment or a combination of systemic and local treatment. The prognosis depends mainly on the subtype of the lymphoma and the extent of the infestation when the diagnosis is confirmed. Even though some effective treatment options are now available, it has not yet been possible to significantly reduce the mortality rate.

CONCLUSION

Many different options are available for the diagnostics and treatment of intraocular lymphomas, which require close interdisciplinary cooperation. The further developments in the field of molecular pathology allow a faster and more accurate diagnosis and could open up new treatment options in the future.

[Excisional surgery of orbital tumors]

The indications for orbital tumor surgery are an incisional biopsy to confirm the diagnosis or in malignant operable tumors a complete excision or a debulking to avoid complications in large invasively infiltrating tumors. In the case of benign tumors, the indications for surgery depend mostly on the clinical symptoms and cosmetic esthetic disfigurement. In the present article the preoperative examinations as well as surgical access approaches to different orbital regions, endoscopic procedures and methods of intraoperative navigation are presented. Magnetic resonance imaging is the instrument of choice, whereby in many cases computed tomography (CT) adds further information. Depending on the indications, diffusion-weighted sequences, CT angiography and digital subtraction angiography (DSA, catheter angiography) are added to the preoperative diagnostics. For space-occupying lesions located anterior to the bulbar equator, an anterior orbitotomy can be performed transconjunctivally or transpalpebrally. A lateral orbitotomy is used to reach lateral, laterocranial, and lateroinferior orbital segments, whereas transcranial approaches are suitable for processes located far posterior and for those with retro-orbital intracranial extension as well as for processes in the optic foramen/superior orbital fissure. The indications for an endonasal access approach are processes medial to the bulb or optic nerve and up to the orbital apex. A transantral access can be chosen for caudal, mediolateral, and medioinferior space-occupying lesions. Modern orbital surgery is complemented by endoscopic procedures and intraoperative navigation. Orbital tumors belong to the interdisciplinary relevant diseases. Therefore, an optimal management takes place at specialized multidisciplinary centers.

A novel approach quantifying the periorbital morphology: A comparison of direct, 2-dimensional, and 3-dimensional technologies

BACKGROUND

The measurement of anatomical structures is critical in plastic and reconstructive surgery. However, few detailed and standardized measurements have been widely used in the periorbital region. This study aimed to evaluate the feasibility of a novel detailed and standardized protocol with 2D and 3D technologies, and explore the relationship between them and direct measurements.

METHODS

Fifty healthy Caucasians (100 eyes) between 20 and 68 years old were recruited and captured for 3D photographs by VECTRA M3 3D Imaging System. Subsequently, 24 landmarks were located on each 3D photographs following a standardized protocol, and then 19 linear and 3 angular periorbital variables were measured. Furthermore, two-dimensional (2D) and direct measurements were conducted on each subject and compared with 3D measurements and one another.

RESULTS

The grand r means across all measurements were 0.77, 0.78, and 0.88 for direct vs. 2D values, direct vs. 3D values, and 3D vs. 2D values, respectively. The mean absolute differences were 1 mm (ranging from 0.2 mm to 3.7 mm) between direct and 3D measurements, 1 mm (ranging from 0.04 mm to 2.4 mm) between direct and 2D measurements, and 1 mm and 6.6° (ranging from 0.04 mm or 0.5° to 3 mm or 12.8°) between 2D and 3D measurements.

CONCLUSIONS

This study verified the feasibility of this detailed and standardized landmark localization protocol for assessing the periorbital morphology with 2D and 3D technologies. This protocol may work as a bridge communicating with all studies involving any of the three technologies in the future.

[Advanced periocular basal cell carcinoma-a therapeutic challenge]

BACKGROUND

Basal cell carcinomas are the most common periocular malignant tumor. In advanced periocular basal cell carcinoma, vismodegib is a new treatment option which might potentially avoid surgical eye removal.

CASE REPORT

We treated a 76-year-old patient unwilling to consent to surgery with vismodegib for advanced periocular basal cell carcinoma on the left forehead that had already undergone several previous treatments. After initial partial remission, the tumor regrew under ongoing therapy, so that radical surgical excision including orbital exenteration was performed. Unfortunately, the patient died thereafter due to septic multi-organ failure.

CONCLUSION

Basal cell carcinoma and its new treatment options are gaining importance for ophthalmology due to rising incidence and prevalence rates. Vismodegib is a new encouraging option. However, for advanced tumors, it must be resolved whether complete histological remission may be achieved to avoid surgical intervention, or whether the area of resection can be significantly reduced. Current multicenter studies investigate these aspects further (ClinicalTrails.gov identifier: NCT03035188).

[Importance of interdisciplinary collaboration for optimal treatment of orbital tumors]

Optimal treatment of tumors with orbital invasion may exceed the competences of an individual medical specialty and require interdisciplinary cooperation. The aim of this article is to present an interdisciplinary treatment concept based on the examples of intraorbital hemangioma and squamous cell carcinoma of the paranasal sinuses infiltrating the orbit. In addition to a detailed medical history and a complete ophthalmological examination, a detailed imaging technique with standardized echography and tomography methods such as orbital thin-slice CT and/or in many cases MRI is essential for the primary classification of an intraorbital pathology. Depending on the type of pathology, a purely surgical procedure involving various disciplines such as ophthalmology, otorhinolaryngology, maxillofacial surgery, neurosurgery, and pathology, or an interdisciplinary treatment regimen including (neo)adjuvant radiotherapy or chemotherapy is necessary. Orbital tumors have a wide range of potential pathologies, requiring complex surgical procedures and multimodal therapies. In case of infiltration of the paranasal sinuses or intracranial structures, an interdisciplinary team including neuroradiologists, oral-maxillofacial surgeons, otorhinolaryngologists, neurosurgeons, radiation therapists, ophthalmologists, pathologists, oncologists, and psycho-oncologists is essential for successful treatment.

[New molecular pathological strategies for malignant iris tumors]

BACKGROUND

Molecular pathological research offers new chances for the diagnostic and therapeutic management of malignant iris tumors. Besides immunohistological and polymerase chain reaction analyses further techniques, such as multiplex ligation-dependent probe amplification, microsatellite analyses and next-generation sequencing are able to detect various mutations in the tumor genome.

OBJECTIVE

An up to date review of new molecular pathological strategies for malignant iris tumors was carried out.

METHODS

This article provides a review of the recent literature based on a PubMed search and clinical experience with iris tumors.

RESULTS

The diagnostic characteristics and targeted treatment options are presented, exemplified by iris melanoma and iris carcinoma metastases. In iris melanomas, mutations in the GNA11 and GNAQ genes (in approximately 85% of the cases) seem to be important. Furthermore, the monosomy-3 status should be investigated in these tumors. In iris lymphomas, molecular pathological analyses are essential for an exact diagnosis. Detection of mutations in MYD88, BRAF, KLF2, ID3, TCF3, STAT3, RHo, TET2, IDH2, CXCR4, CD79B and DNMT3A are helpful. In particular, the detection of the CD20 antigen is of therapeutic relevance because this lymphoma subgroup responds well to rituximab, a CD20 antibody treatment. In iris carcinoma metastases, investigations for mutations are helpful because then a targeted treatment seems to be possible.

CONCLUSION

Molecular pathological analyses will become essential in the future management of iris tumors because they play a key role towards a personalized treatment approach.

[Minimally invasive bypass surgery for nasolacrimal duct obstruction : Transcanalicular laser-assisted dacryocystorhinostomy]

BACKGROUND

In recent years, the minimally invasive surgical procedure of transcanalicular laser-assisted dacryocystorhinostomy (TKL-DCR) has gained importance in the treatment of primary acquired nasolacrimal duct obstructions (PANDO).

OBJECTIVES

Surgical indications, functional success rates, potential advantages, and complications of TKL-DCR are presented and compared with the standard procedures external (EXT-DCR) and endonasal DCR (EN-DCR).

METHODS

The study comprises a PubMed literature review and our own clinical results.

RESULTS

Using TKL-DCR either as the primary surgical treatment for PANDO, or as a secondary procedure following failure (reobstruction of the surgical ostium) of previous EXT-DCR resulted in good functional success rates (60-90%). The duration of surgery (10-15 min) and the period of recovery are significantly shorter than in EXT-DCR. Visible cutaneous scars and significant postoperative nose bleeding are not among the complications of TKL-DCR, due to the lack of a skin incision and the coagulative ability of the diode laser. The smaller sized surgical ostium has been considered the main disadvantage of TKL-DCR, since it might be prone to earlier reobstruction. On the other hand, TKL-DCR spares the anatomical structures that form the physiological tear pump, which should favor tear drainage. In very few cases, thermal damage to the canaliculus has been observed as a complication.

CONCLUSIONS

Given the satisfying functional results, TKL-DCR is a valid alternative to the "gold standard" procedure EXT-DCR, especially in patients who particularly request speedy recovery and who do not want to take the risk of visible skin scaring. Future studies will have to investigate whether the smaller surgical ostia of TKL-DCR remain patent and whether functional success rates decrease during a longer follow-up period of >2 years.

[CyberKnife®: new treatment option for uveal melanoma]

BACKGROUND

CyberKnife® stereotactic radiosurgery is a new treatment option for uveal melanoma.

OBJECTIVE

This review outlines the technique of robot-assisted CyberKnife® therapy, as well as the pros and cons in the treatment of uveal melanoma.

METHODS

The study provides a PubMed literature review and own preliminary clinical experiences.

RESULTS

CyberKnife® therapy for choroidal and ciliary body melanomas shows comparable results concerning local tumor control and overall survival matching those of conventional therapies. With only low complication rates, a high level of quality of life can be conserved by possible preservation of visual acuity as well as the ocular globe.

CONCLUSION

Stereotactic radiosurgery using CyberKnife® seems to be an efficient and safe therapeutic option for malignant melanomas affecting the choroid and ciliary body. Comparative studies with conventional radiation strategies are now a high priority.

[Corneal donation : Dilemma between growing demand and declining donor rate]

BACKGROUND

One of the most important requirements for successful corneal transplantation is the availability of donor tissue and thus the approval for postmortem corneal tissue donation. The aim of this study was to investigate donor willingness compared to the continuously increasing demand in recent years.

MATERIAL AND METHODS

Archives of the local eye bank at the Department of Ophthalmology, University of Cologne, Germany in the time period between 1 July 2011 and 31 December 2015 were examined regarding the willingness for corneal donations in deceased patients from the University Hospital of Cologne. Absolute numbers of deceased, exclusion criteria for donation as well as the rate of negative and affirmative decisions were evaluated.

RESULTS

In 235 (5.1 %) out of 4593 deceased at the University Hospital of Cologne, corneal donation was accomplished during the observation period. Of the patients 2923 (63.6 %) were excluded because of absolute contraindications for corneal donation and the rate of absolute contraindications increased from 46.6 % in 2011 to 68.9 % in 2015. Willingness for corneal donation in potentially suitable deceased patients diminished from 34.9 % in 2011, to 34.3 % in 2012, 35.5 % in 2013, 28.4 % in 2014 and to 24.1 % in 2015. In relation to the total number of deceased, the number of corneal tissue donations decreased from 11.5 % in 2011 to 3.5 % in 2015.

CONCLUSION

Despite a rising demand, data from Cologne seem to indicate that the number of corneal donations has declined to some extent. In order to increase the number of corneal donors in the future, further educational work as well as standardization and optimization of the tissue donation process seem to be urgently needed.

[Influence of 20 % sulfur hexafluoride (SF6) on human corneal endothelial cells : An in vitro study]

BACKGROUND

In posterior lamellar keratoplasties, such as Descemet membrane endothelial keratoplasty (DMEK) and Descemet's stripping automated endothelial keratoplasty (DSAEK) an air bubble is left inside the anterior chamber to promote graft attachment during the early postoperative period. In the case of insufficient graft adhesion a renewed intracameral air injection is often necessary. The use of sulfur hexafluoride diluted with air (SF6 20 %) as an alternative to pure air may further enhance graft attachment and reduce the rebubbling rate. The effect of SF6 20 % on corneal endothelium is currently unclear and was therefore examined in vitro.

MATERIAL AND METHODS

For this study 12 human corneoscleral discs were mounted in artificial anterior chambers, the systems were continuously filled with culture medium and the anterior chambers with air (n = 5) or SF6 20 % (n = 7) as tamponade. After 6 days of storage in the incubator endothelial cell density, toxicity on endothelial cells and corneal thickness were evaluated.

RESULTS

There were no significant differences in endothelial cell loss (p = 1.000), endothelial cell count (p = 0.648), toxicity on endothelial cells (p = 0.048) and central corneal thickness (p = 0.905) between the two groups after 1 week. The level of significance was defined as p ≤ 0.05 and adjusted to p ≤ 0.0056 according to the Bonferroni correction for multiple testing.

CONCLUSION

The use of SF6 20 % as tamponade in the anterior chamber for posterior lamellar keratoplasty can be proposed as a safe alternative to pure air filling related to endothelial cell loss. Increased toxic effects on the corneal endothelium by SF6 20 % were not detected in this study; however, further prospective clinical trials are needed to examine the long-term effects in humans.

[Ocular prosthetics. Fitting, daily use and complications]

BACKGROUND

Ocular prosthetics make a decisive contribution to the functional, esthetic and psychosomatic rehabilitation of patients after ocular extirpation.

OBJECTIVES

This article provides an overview of the fitting, daily care and complications of ocular prosthetics.

METHODS

The study comprised a PubMed literature review and own clinical results.

RESULTS

Ocular prosthetics made from cryolite glass or perspex can be manufactured and fitted 5-8 weeks after removal of the eye. During this period a conformer is placed within the conjunctival sac in order to prevent scar formation and shrinking of the socket. Artificial eyes can be worn continuously, only interrupted by a short but regular cleaning procedure. Artificial tears and lid hygiene improve the comfort of wearing. Glass prostheses have to be renewed every 1-2 years, while perspex prostheses need to be polished once a year. Complications, such as giant papillary conjunctivitis or blepharoconjunctivitis sicca are facilitated by poor fit, increased age and inappropriate care of the prosthetic device. In the case of socket shrinkage or anophthalmic socket syndrome, surgical interventions are needed to re-enable the use of an artificial eye.

CONCLUSION

Adequate fitting, daily care of ocular prosthetics and therapeutic management of associated complications are mandatory for a durable functional, esthetic and psychosomatic rehabilitation after ocular extirpation.

[Immunotherapy of uveal melanoma: vaccination against cancer. Multicenter adjuvant phase 3 vaccination study using dendritic cells laden with tumor RNA for large newly diagnosed uveal melanoma]

Uveal melanomas are the most common malignant tumors of the eye. With modern molecular biological diagnostic methods, such as chromosome 3 typing and gene expression analysis, these tumors can be categorized into highly aggressive (monosomy 3, class II) and less aggressive forms. This molecular biological stratification is primarily important for determining the risk of these tumors as no therapy is currently available that is able to prevent or delay metastases. A randomized study of patients with a poor prognosis (monosomy 3) is currently being carried out in order to determine whether a cancer vaccine prepared from autologous (patient's own) dendritic cells and uveal melanoma RNA can prevent or delay progression and further metastases of this extremely aggressive form of cancer. Inclusion in the uveal melanoma study, which hopes to provide a potential therapeutic option for patients, is only possible if patients are referred to an institution that is able to manufacture and provide this vaccination before the patient is operated on or treated with radiation. Untreated tumor material is necessary for producing the vaccine on an individualized patient basis.

[Transcanalicular Laser Dacryocystorhinostomy: One-Year-Experience in the Treatment of Acquired Nasolacrimal Duct Obstructions]

BACKGROUND

External dacryocystorhinostomy (DCR) is at present the gold standard for the surgical treatment of acquired nasolacrimal duct obstructions, but tremendous progress has been made in recent years in improving minimally invasive techniques, sparing not only the skin, but also the medial lid structures, which contribute to the physiological palpebral-canalicular pump mechanism. The purpose of this study is to report our 1-year experience with the surgical technique, complications and results of transcanalicular laser assisted DCR.

PATIENTS AND METHODS

48 consecutive transcanalicular laser-assisted DCRs combined with bicanalicular silicone intubation were performed for acquired nasolacrimal duct obstruction, and evaluated for intra- and postoperative complications, as well as subjective and objective success rates.

RESULTS

Transcanalicular laser-assisted DCR combined with bicanalicular silicone intubation was surgically feasible in 45 cases (94 %). In 3 patients (6 %) it was impossible to position the aiming beam correctly at the anteroinferior rim of the middle turbinate using the superior canalicular approach, due to superior orbital rim prominence. Therefore 2 patients received no silicone intubation, despite a patent osteotomy at the back of the middle turbinate, and 1 patient underwent intraoperative conversion to external DCR due to anatomical narrowness of the nasal cavity. Perioperatively, 1 patient developed canalicular infection, 1 patient exhibited thermal injury to the canaliculus, and 4 patients exhibited premature prolapse of the silicone tube. At 6-months follow-up, functional success--defined as resolution of preoperative symptoms--was achieved in 35 of 45 surgically successful transcanalicular laser-assisted DCRs (78 %). Of the 10 postoperative failures (22 %), all patients reported epiphora, 6 patients were unable to irrigate the lacrimal drainage system, and 6 patients required surgical revision using external DCR.

CONCLUSIONS

Transcanalicular laser assisted DCR is a promising minimally invasive approach for the surgical treatment of acquired nasolacrimal duct obstruction, in order to fill the gap between recanalising first step procedures and external DCR.

[Current aspects of eyelid, lacrimal and orbital surgery in childhood]

BACKGROUND

During childhood the spectrum of disorders of the eyelid, the lacrimal drainage system and the orbit as well as the subsequent therapeutic management differ from those in adults.

OBJECTIVES

This review outlines the clinical picture and treatment of the most common eyelid, lacrimal drainage and orbital diseases in childhood.

METHODS

The study comprises a PubMed literature review and own clinical results.

RESULTS

The most common eyelid disorders in childhood include congenital malpositions, such as ptosis or entropium, which may require fast surgical correction in order to prevent amblyopia. For connatal dacryostenosis a step-by-step therapeutic approach is recommended: (1) conservative treatment using lacrimal sac massage, astringent eye and nose drops, (2) irrigation and probing of the nasolacrimal system and (3) irrigation, probing and silastic tube intubation under general anesthesia. Benign orbital lesions such as dermoid cysts can be removed at pre-school age. Using systemic beta blockers is a novel conservative approach in the treatment of capillary hemangioma, which should precede surgical interventions.

CONCLUSION

Eyelid and orbital diseases during childhood may require fast surgical intervention to prevent amblyopia. Initial conservative treatment is recommended for connatal dacryostenosis and capillary hemangioma.

[Prevention and management of complications in Descemet membrane endothelial keratoplasty (DMEK) and Descemet stripping automated endothelial keratoplasty (DSAEK)]

BACKGROUND

Posterior lamellar keratoplasty, in the form of Descemet membrane endothelial keratoplasty (DMEK) and Descemet stripping automated endothelial keratoplasty (DSAEK), has become a standard procedure for therapy of endothelial diseases of the cornea. The aim of this article is to describe strategies to prevent and manage complications in DMEK and DSAEK surgery.

METHODS

The article is based on a PubMed literature search and own clinical data. Key words used were "DMEK", "DSAEK", "Descemet membrane endothelial keratoplasty" and "Descemet stripping automated endothelial keratoplasty".

RESULTS

The DMEK and DSAEK procedures are safe surgical strategies for treating endothelial corneal diseases if the indications are made correctly.

CONCLUSIONS

The DMEK procedure is the standard procedure for improvement of visual acuity especially for younger patients with Fuchs' dystrophy and DSAEK is particularly suitable for eyes with complicated anterior chamber situations.

Two-step retrograde closed stenting: a novel method for treating canalicular lacerations in Chinese patients

PURPOSE

To evaluate the efficacy of two-step retrograde closed stenting for treating canalicular laceration. methods: Forty-eight consecutive canalicular laceration cases (48 eyes) were randomised and divided into two groups: a one-step group and a two-step group. In the two-step group (23 cases), the first step was performed in the outpatient department and included identifying the medial cut end of the canaliculus and probing under a slit-lamp microscope, followed by a retrograde canalicular stenting assisted by a memory titanium stylet. The second step was canalicular anastomosis, which was performed in the operating room. In the one-step group (25 cases), all of the surgical procedures were performed when preoperative preparations were simultaneously available.

RESULTS

The time elapsed from the doctor visit to the treatment was 4.3 ± 2.4 h in the two-step group and 18.8 ± 6.3 h in the one-step group (P<0.01). The canalicular medial cut ends were found in all cases, but 8.6 ± 3.5 min was needed in the two-step group, and 51.4 ± 24.2 min was needed in the one-step group (P<0.01). The numerical rating scale for pain during surgery was 1.8 ± 1.2 in the two-step group and 5.4 ± 2.2 in the one-step group (P<0.01). One case (2.63%) in the two-step group and nine cases (36%) in the one-step group required other assisted methods to locate the medial cut end (P=0.007). Twenty-one cases (91.3%) in the two-step group and 20 cases (80%) in the one-step group achieved patent lacrimal drainage systems during a 12-month follow-up (P=0.528).

CONCLUSIONS

The two-step canalicular anastomosis method allows an early search for the medial cut end of the canaliculus and improves the chances of finding it; it is also a quicker, less invasive method for treating canalicular lacerations.

"OSMO-UT-DSAEK" using THIN-C medium

BACKGROUND

When performing ultra-thin Descemet's stripping automated endothelial keratoplasty (UT-DSAEK), the quality of the stromal interface and stromal thickness seem to be critical for visual outcome. The aim of this study was to investigate whether additional osmotic deswelling prior to UT-DSAEK improves the quality of the cut surface and leads to a more reliable and deeper cut in UT-DSAEK ("OSMO-UT-DSAEK").

METHODS

Seventeen human donor corneas not usable for transplantation were used in this experiment. After standard deswelling with culture Medium II, ten corneas were randomly assigned to be additionally deswollen within THIN-C medium. The other remaining seven corneas were put back into culture Medium II. All corneas were placed in an artificial anterior chamber system (Moria); a double path cutting procedure using a microkeratome (Moria) was then performed. Corneal thickness was measured by ultrasound biomicroscopy and in paraffin-embedded slides, followed by histological grading of the cut surface.

RESULTS

Stromal interface smoothness significantly improved after preconditioning in THIN-C medium (Pearson P = 0.019). The correlation of the corneal thickness obtained by UBM (mean 706 ± SD 208 μm) and histology (mean 530 ± SD 159 μm) was not significant (Pearson r = 0.11, P > 0.05, mean difference 247, 95 % CI [+50;+304]). We found no significant correlation between the microkeratome setting and the actual thickness of the lenticule measured in histological analysis in both media as well as for the first and second cut (first cut: Pearson r = 0.9, P = 0.1, 95 % CI [-10;+96], second cut: Pearson r = 0.9, P = 0.4, 95 % CI [-10;+22]).

CONCLUSION

Preconditioning of corneas with THIN-C medium significantly improved the quality of the graft interface in UT-DSAEK, but did not significantly improve the cut precision of the microkeratome.

[Anti(lymph)angiogenic preconditioning prior to keratoplasty]

PURPOSE

The aim of this study is to describe novel therapeutic concepts to promote graft survival in high-risk keratoplasty by targeting (lymph)angiogenesis in the transplant context.

METHODS

A PubMed literature search and our own clinical and experimental data are evaluated.

RESULTS

There are three options for anti(lymph)angiogenic preconditioning: a) primary prevention of neovascularisation during the disease process, b) secondary prevention by regressing established blood vessels prior to transplantation and (c) tertiary prevention through inhibition of post-keratoplasty neovascularisation.

CONCLUSION

Modern topical anti(lymph)angiogenic therapies seem to be able to reduce the risk of graft rejection especially in high-risk keratoplasty.

[Split-cornea transplantation - a novel concept to reduce corneal donor shortage]

BACKGROUND

Penetrating keratoplasty is at present the gold standard for corneal transplantation, but tremendous progress has been made in recent years in improving lamellar keratoplasty techniques, such as deep anterior lamellar keratoplasty (DALK) and Descemet membrane endothelial keratoplasty (DMEK). The purpose of this report is to describe split-cornea transplantation by combining DALK and DMEK as a novel concept to reduce donor shortage.

METHODS

The study consists of a PUBMED literature review and our own clinical results.

RESULTS

Splitting of a single donor cornea into an anterior part (including epithelium, its basement membrane, Bowman layer, and stroma) for use in a DALK procedure in a patient with anterior-stromal disease (e. g., keratoconus) and into a posterior part (endothelium-Descemet membrane layer) for use in a DMEK procedure in a patient with endothelial disease (e. g., Fuchs endothelial dystrophy) can reduce the need for corneal donor tissue by around 50 %. A short-term 6-months follow-up has revealed good visual and refractive outcomes with low complication rates and acceptable endothelial cell loss.

CONCLUSION

Split-cornea transplantation by combining DALK and DMEK surgeries is a promising concept to reduce donor shortage in corneal transplantation surgery in the future.

[Selective lacrimal sac biopsy for external dacryocystorhinostomy: a clinical pathological study]

BACKGROUND

Tumors of the lacrimal drainage system are rare but potentially life-threatening. The purpose of this study was to investigate the applicability of selective lacrimal sac biopsy in 500 cases of external dacryocystorhinostomy for acquired dacryostenosis.

PATIENTS AND METHODS

Lacrimal sac biopsy was obtained selectively for atypical clinical and/or intraoperative findings. The frequency and spectrum of biopsies were recorded and correlated with the follow-up results.

RESULTS

Lacrimal sac biopsy was performed in 19 external dacryocystorhinostomies (3.8%) including non-Hodgkin B-cell lymphoma (3), squamous carcinoma (2), mucoepidermoid carcinoma (1), malignant melanoma (1), oncocytoma (1), pyogenic granuloma (4), Wegener's granulomatosis (4) and sarcoidosis (3). Within 5 years none of the patients without biopsy developed systemic inflammatory diseases or lacrimal neoplasms. The 5-year survival was 87% in patients with significant lacrimal sac pathology and 96% in patients without significant pathology.

CONCLUSION

External dacryocystorhinostomy with selective biopsy for atypical clinical and intraoperative findings allows safe diagnosis and management of potentially life-threatening lacrimal lesions.

[Malignant melanoma of the lacrimal sac]

A 68-year-old woman presented with a 10-month history of right-sided epiphora, bloody tears, and medial canthal mass. Computed tomography revealed a soft tissue mass of the right lacrimal sac with widening of the bony nasolacrimal canal. External dacryocystorhinostomy with incisional biopsy confirmed the diagnosis of malignant melanoma. After staging, further therapy included orbital exenteration, lateral rhinotomy with en bloc resection of the lacrimal drainage apparatus, and adjuvant radioimmunotherapy. One year after surgery, no evidence of local recurrence or metastatic disease could be detected.

Hochdosisbrachytherapie des malignen Aderhaut- und Ziliarkörpermelanoms mit 106Ruthenium

BACKGROUND

The purpose of this study was to report the multifactorial results of high-dose (106)Ruthenium plaque brachytherapy for (cilio-)choroidal melanoma and to confirm them by histological examinations.

PATIENTS AND METHODS

100 patients with choroidal or ciliochoroidal melanoma treated by high-dose 106Ruthenium plaque brachytherapy were followed-up for 5 years. 12 secondary enucleated eyes were compared to a non-irradiated matched group by light microscopy.

RESULTS

The 5-year local tumour control rate was 93%, the 5-year survival rate 91%. Late radiogenic side effects occured as a retinopathy in 13%, as an optic neuropathy in 5% and as a secondary glaucoma in 3% of the patients. 14% had to be enucleated, 10% developed metastases. The histopathologic examination revealed significantly higher degrees of necrosis (p=0,041), balloon cell degeneration (p=0,025) and fibrosis (p<0,001) in the irradiated melanomas than in the control tumours.

CONCLUSION

High-dose 106Ruthenium plaque brachytherapy turned out to be an effective treatment procedure for posterior uveal melanoma (not exceeding a prominence of 5,5 mm) with a high rate of local tumour control and a low rate of side effects.

Cytokeratin expression results in a drug-resistant phenotype to six different chemotherapeutic agents

The cytokeratin network is an abundant cytoplasmic system whose function is largely unknown. Recently, we have found that the introduction of a cytokeratin network into eukaryotic cells results in a drug resistance phenotype. The current study was undertaken to determine the universal nature of this phenomenon by investigating the survival response of two different cell lines to six different DNA-damaging agents using two different assays of cell survival. To correlate our in vitro assays of survival with known in vivo responses to DNA damage, we compared the apoptotic response of cytokeratin-positive and cytokeratin-negative cell lines. The results show that the introduction of a cytoskeletal network confers a resistant phenotype to mitoxantrone, doxorubicin, melphalan, bleomycin, and mitomycin C in the different cytokeratin-positive cell lines. No survival advantage was noted when damage was conferred by cisplatin or UV irradiation. We found the cytokeratin-positive cell lines were protected from apoptosis, while the cell lines without cytokeratins showed apoptosis in response to mitoxantrone exposure. Cytokeratin-dependent drug resistance is observed in different cell lines but is not observed with all DNA-damaging agents. The data suggest that the mechanism of this drug resistance may be attributed, in part, to a cytokeratin-conferred protection against apoptosis.

Promoter sequences required for transcription of Xenopus laevis histone genes in injected frog oocyte nuclei

Amphibian oogenesis is accompanied by the accumulation of histone mRNA and proteins in the absence of ongoing DNA replication. To begin an analysis of the mechanisms by which histone gene expression is regulated during frog oogenesis and embryogenesis, we used oocyte injection to examine the upstream sequences required for transcription of genes encoding each of the five histone classes. We found that sequences necessary for maximal levels of transcription are located 100 to 200 base pairs upstream of the corresponding start sites. In this region, each promoter examined contains conserved sequence elements, several of which seem to be histone gene class specific, in addition to other, more common sequence elements believed to be used by general transcription factors.