[Chronic pancreatitis : Characterization and differentiation from pancreatic cancer]. / Chronische Pankreatitis : Charakterisierung und Differenzierung zum Pankreaskarzinom.

CLINICAL/METHODOLOGICAL ISSUE: Chronic pancreatitis (CP) is a long-lasting inflammation of the pancreas that changes the normal structure and function of the organ. There are a wide range of inflammatory pancreatic diseases, of which some entities, such as focal pancreatitis (FP) or "mass-forming pancreatitis," can mimic pancreatic ductal adenocarcinoma (PDAC). As a consequence, a misdiagnosis can lead to avoidable and unnecessary surgery or delay of therapy. STANDARD RADIOLOGICAL METHODS: The initial imaging method used in pancreatic diseases is ultrasound due to its availability and low cost, followed by contrast-enhanced computed tomography (CE-CT), which is considered a workhorse in the diagnostic work-up of diseases of the pancreas. Magnetic resonance imaging (MRI) and/or MR cholangiopancreatography (MRCP) can be used as a problem-solving tool to distinguish between solid and cystic lesions, and to rule out abnormalities in the pancreatic ducts, such as those associated with recurrent acute pancreatitis (AP) or to show early signs of CP. MRCP has essentially replaced diagnostic endoscopic retrograde cholangiopancreatography (ERCP) in the initial assessment before any therapeutic intervention. PRACTICAL RECOMMENDATION: The following review article summarizes the relevant features of CT and MRI that can help to make the diagnosis of CP and to aid in the differentiation between focal pancreatitis and PDAC, even in difficult cases.

Fast high-precision distance metrology using a pair of modulator-generated dual-color frequency combs.

We demonstrate fast high-precision non-contact distance measurements to technical surfaces using a pair of dual-color electro-optic frequency combs for synthetic-wavelength interferometry (SWI). The dual-color combs are generated from continuous-wave (cw) lasers at 1300 nm and 1550 nm, which are jointly fed to a pair of high-speed dual-drive Mach-Zehnder modulators. The dual-color approach is used for continuous and dead-zone-free compensation of temperature-induced fiber drift. We achieve standard deviations below 2 µm at an acquisition time of 9.1 µs for measurements through 7 m of single-mode fiber. Despite the technical simplicity of our scheme, our concept can well compete with other comb-based distance metrology approaches, and it can maintain its accuracy even under industrial operating conditions. The viability of the concept is demonstrated by attaching the fiber-coupled sensor head to an industrial coordinate measuring machine for acquisition of surface profiles of various technical samples. Exploiting real-time signal processing along with continuous fiber drift compensation, we demonstrate the acquisition of point clouds of up to 5 million data points during continuous movement of the sensor head.

[Non-antagonistic influence of Krumeich's intrastromal corneal ring in an experimental tissue culture system]. / Nichtantagonistische Wirkungsweise des intrastromalen Krumeich-Kornearings in einem experimentellen Gewebekultursystem.

BACKGROUND: Intrastromal insertion of Krumeich's corneal ring between graft and residual host corneal tissue appears to impair preripheral, superficial and superfluous vascularization of donor corneal tissue. OBJECTIVES: The purpose of this study was to investigate the cytotoxic effects of Krumeich's ring using tissue cultures composed of primary human dermal microvascular endothelial cells from adult donors (HMVEC). MATERIALS AND METHODS: Soluble growth medium extracts of the individual components of Krumeich's ring alloy were prepared and HMVEC were exposed to these extracts in triplicate for 1 day followed by investigation with 3­(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Furthermore, HMVEC were cultured for 5 days on either Krumeich's ring or polypropylene (PP) discs coated with individual components of the Krumeich's ring alloy followed by double vital staining with fluorescein diacetate (FDA) and propidium iodide (PI). RESULTS: The MTT assays revealed that higher doses of the extracts appeared to reduce the viability of HMVEC, while highly diluted extracts of molybdenum (Mo) powder appeared to increase the metabolic activity of HMVEC. The FDA-PI staining showed only a few live HMVEC on either cobalt (Co) or Mo-coated PP discs, compared to the respective titanium (Ti) and chromium (Cr) counterparts. Viable HMVEC appeared to attach to Krumeich's ring after a 5­day incubation period. CONCLUSION: The results confirm that Krumeich's ring does not exert measurable cytotoxic effects in our chosen assay system. High dilutions of medium-soluble Mo powder extracts appear to increase the metabolic activity of HMVEC.

Bovine adenoviruses--IV. Two mixed antigens for routine serodiagnosis by complement fixation reaction.

The frequency of bovine adenovirus infections occurring in cattle has been grossly underestimated up to the present day. Primary isolation of serotypes belonging to bovine subgroup II is cumbersome. Hardly any laboratory has used all 8 officially-recognised bovine serotypes in seroneutralisation-tests, which should be done when this type-specific method is used for serodiagnosis. The complement fixation test, known as group-reactive from human adenovirus serology, has failed to disclose the true incidence of bovine infections, as until recently the importance of a novel additional group-reactive bovine adenovirus antigen has been undisclosed. Here we describe production, composition and performance of two mixed antigens for complement fixation reactions, which take into account recent findings by our team on peculiarities of bovine adenovirus antigens. Mixed antigen 1 contains bovine serotypes 1, 2 and 3 and detects group-specific antibodies of the classical mastadenoviruses. Mixed antigen 2 contains bovine serotypes 4, 5, 6, 7 and 8 and determines group-specific antibodies against the novel paramastadenoviruses. In addition, each antigen is capable of demonstrating complement-fixing type-specific antibodies in sera against the respective types included in each mixed antigen, with a net enhancing effect produced by mixing. Use of the 2 mixed antigens promptly shows whether bovine adenoviruses, presently recognised as well as unclassified, are involved in a given outbreak of respiratory or enteric disease of cattle. If needed, the responsible type may be determined in a second step of serological investigation.

Acetaminophen versus acetaminophen with codeine after pediatric tonsillectomy.

OBJECTIVE: To compare the effectiveness of acetaminophen versus acetaminophen with codeine after pediatric tonsillectomy and adenoidectomy. STUDY DESIGN: Prospective, randomized, double-blind study. METHODS: Fifty-one children ages 3 to 12 years scheduled for outpatient tonsillectomy and adenoidectomy were studied. Patients were randomly assigned to receive acetaminophen or acetaminophen with codeine in unlabeled bottles for postoperative pain control. The Wong-Baker FACES pain rating scale was used to help children quantify their level of pain after surgery. The level of pain, quantity of pain medication required, presence of side effects, and the percentage of a normal diet consumed was recorded for 10 postoperative days. RESULTS: There was no difference (P > .05, all time points) in the level of postoperative pain reported by the parents and children in the two groups. The acetaminophen with codeine group tended to have increased problems with nausea, emesis, and constipation, but these differences did not reach statistical significance. Children in the acetaminophen group consumed a significantly higher percentage of a normal diet on the first 6 postoperative days (P < .05, all time points). CONCLUSION: There was no difference in the level of pain control provided by acetaminophen and acetaminophen with codeine as measured by the Wong-Baker FACES pain rating scale. Postoperative oral intake was significantly higher in children treated with acetaminophen alone.

Safety and biological efficacy of an adeno-associated virus vector-cystic fibrosis transmembrane regulator (AAV-CFTR) in the cystic fibrosis maxillary sinus.

OBJECTIVE: The host immune response and low vector efficiency have been key impediments to effective cystic fibrosis transmembrane regulator (CFTR) gene transfer for cystic fibrosis (CF). An adeno-associated virus vector (AAV-CFTR) was used in a phase I dose-escalation study to transfer CFTR cDNA into respiratory epithelial cells of the maxillary sinus of 10 CF patients. STUDY DESIGN: A prospective, randomized, unblinded, dose-escalation, within-subjects, phase I clinical trial of AAV-CFTR was conducted. PATIENTS: Ten patients with previous bilateral maxillary antrostomies were treated. MAIN OUTCOME MEASURES: Safety, gene transfer as measured by semiquantitative polymerase chain reaction (PCR), and sinus transepithelial potential difference (TEPD) were measured. RESULTS: The highest level of gene transfer was observed in the range of 0.1-1 AAV-CFTR vector copy per cell in biopsy specimens obtained 2 weeks after treatment. When tested, persistence was observed in one patient for 41 days and in another for 10 weeks. Dose-dependent changes in TEPD responses to pharmacologic intervention were observed following treatments. Little or no inflammatory or immune responses were observed. CONCLUSION: AAV-CFTR administration to the maxillary sinus results in successful, dose-dependent gene transfer to the maxillary sinus and alterations in sinus TEPD suggestive of a functional effect, with little or no cytopathic or host immune response. Further study is warranted for AAV vectors as they may prove useful for CFTR gene transfer and other in vivo gene transfer therapies. A prospective, randomized, double-blind, placebo-controlled, within-subjects, phase II clinical trial of the effect AAV-CFTR on clinical recurrence of sinusitis will determine the clinical efficacy of AAV gene therapy for CF.

Otoplasty. Clinical protocol and long-term results.

OBJECTIVE: To evaluate the long-term results after otoplasty on prominent ears. DESIGN: Between 1988 and 1993, ear protrusion was measured preoperatively and postoperatively in pediatric patients undergoing otoplasty by means of a standard protocol based on the Frankfort horizontal line. Patients were asked to return for follow-up measurements a minimum of 1 year after surgery. At the time of follow-up, a patient satisfaction survey was completed by the patients and their families. SETTING: The Hospital for Sick Children, Toronto, Ontario, a tertiary care children's hospital. PARTICIPANTS: Thirty-one of 51 patients returned for follow-up an average of 3.7 years after surgery. RESULTS: One third of ears returned to their original position, one third of ears stayed in a position equal to the immediate postoperative position, and one third of ears had final positions between the preoperative and post-operative positions. At the superior rim, an average of 58% of the operative medialization was lost. Good to excellent ear-to-ear symmetry was obtained in 78% of patients who returned for follow-up. Retrospective chart review showed a revision surgery rate of 3%; stitch granulomas were removed in 9% of patients. The patient satisfaction survey found that 85% of patients were happy or very happy with their ears. CONCLUSIONS: With time, a substantial loss of correction can be expected in most (but not all) patients who undergo otoplasty, particularly at the upper pole. Overall, patients and their families are happy with the results of otoplasty surgery.

Safety of pediatric short-stay tonsillectomy.

OBJECTIVE: To determine the safety of a relatively brief (<3-hour) period of postoperative observation prior to discharge in children undergoing outpatient tonsillectomy. DESIGN: Retrospective chart review. SETTING: Tertiary care children's hospital and public teaching hospital. PATIENTS: The records of all patients (12 years of age who underwent tonsillectomy or adenotonsillectomy from November 1995 through July 1997 were reviewed. A total of 143 patients scheduled for ambulatory treatment were identified; 9 were excluded owing to insufficient follow-up. The remaining 134 patients made up the study group. MAIN OUTCOME MEASURES: (1) Duration of observation prior to discharge; (2) complication rates. RESULTS: The mean age of the study population was 6.1+/-2.6 (mean+/-SD) years. Obstructive sleep apnea was an indication for surgery in 86.5%. Eleven (8.2%) of 134 planned outpatients were electively admitted from the recovery room for inpatient observation, most often because of respiratory compromise. Patients admitted from the recovery room were significantly younger (mean age, 4.0 years) than those who were discharged as planned (6.3 years, P<.001). One hundred twenty-three patients were discharged from the recovery room as anticipated, following a mean+/-SD duration of postoperative observation of 144+/-48 minutes. Overall, 5 (4.1%) of these 123 outpatients suffered complications after discharge. Two patients (1.6%) experienced primary bleeding, both at 8 hours after surgery. Four patients (3.2%) were readmitted. The complication rate did not vary significantly with the duration of postoperative observation (P= .71). CONCLUSION: A short postoperative observation period is safe, with a low rate of complications, in appropriately selected children scheduled for ambulatory tonsillectomy.

Nasal growth after external septoplasty in children.

OBJECTIVE: To assess the impact of external septoplasty surgery on nasal growth in children. DESIGN: Twelve anthropometric measurements (9 linear and 3 angular) were obtained in patients who previously underwent external septoplasty surgery for severe nasal obstruction caused by septal deviation anterior to the nasal spine. Surgery consisted of excision, refashioning, and reinsertion of the quadrilateral cartilage. From these 12 measurements, 5 proportional indexes were calculated, and then all measurements and proportions were compared with previously published norms. Follow-up measurements were taken at least 2 years after surgery (average, 3.4 years). SETTING: The Hospital for Sick Children, Toronto, Ontario, a tertiary care children's hospital. PARTICIPANTS: Twenty-eight patients who underwent external septoplasty surgery between the ages of 6 and 15 years. RESULTS: The principal measurements of the face and nose were within 1 SD of the normative mean for the majority of those in the study group. This was true for nasal height, nasal tip protrusion, nasal width, columella width, columella length, upper face height, face height, face width, inclination of the upper face, inclination of the nasal dorsum, and inclination of the columella. Values for 4 of the 5 proportional indexes were also overwhelmingly in the normal range. Twenty-nine percent of nasal dorsum measurements and 57% of nasal dorsum indexes were more than 2 SDs from the mean, indicating a predominance of short nasal dorsums. CONCLUSIONS: External septoplasty does not affect most aspects of nasal and facial growth, but it may negatively influence growth of the nasal dorsum. Prospective studies are needed to clarify this issue.

Ankyloglossia: incidence and associated feeding difficulties.

OBJECTIVES: To determine the incidence of ankyloglossia (tongue-tie) in the well-baby population, and to determine whether patients with ankyloglossia experience breastfeeding difficulties. DESIGN: Prospective controlled study. SETTING: Tertiary care children's hospital. PATIENTS: A total of 1041 neonates in the well-baby nursery were screened for ankyloglossia. Those positively identified were invited to participate in the study. Mothers of newborns with ankyloglossia and mothers of a matched control group of unaffected newborns were contacted by telephone on a monthly basis for 6 months after their children were discharged from the hospital to determine the presence of breastfeeding difficulties. MAIN OUTCOME MEASURES: Incidence of ankyloglossia, percentage of infants successfully breastfed, and incidence of breastfeeding difficulties. RESULTS: Fifty newborns were identified with ankyloglossia, for an incidence of 4.8% The male-female ratio was 2.6:1.0. Of the 36 mothers of affected infants who were followed up and who intended to breastfeed, 30 (83%) successfully breastfed their infants for at least 2 months, compared with 33 (92%) of the 36 mothers of infants in the matched control group (P = .29). Breastfeeding difficulties were experienced by 9 (25%) of the mothers of infants with ankyloglossia compared with 1 (3%) of the control mothers (P<.01). CONCLUSION: Ankyloglossia, which is a relatively common finding in the newborn population, adversely affects breastfeeding in selected infants.

Impact of tympanostomy tubes on child quality of life.

BACKGROUND: The objective benefits of tympanostomy tubes for otitis media are well established, but the subjective impact of surgery on child quality of life (QOL) has not been systematically studied. OBJECTIVES: To determine the subjective impact of tympanostomy tubes on child QOL, and to compare the variability in QOL before surgery with that observed after surgery. DESIGN: Prospective, observational, before-and-after trial. SETTING: Fourteen referral-based pediatric otolaryngology practices in the United States. PATIENTS: Consecutive (64%) and convenience (36%) sample of 248 children (median age, 1.4 years) with otitis media scheduled for bilateral tympanostomy tube placement as an isolated surgical procedure. INTERVENTION: Tympanostomy tubes were inserted as part of routine clinical care. Validated measures of QOL (OM-6 survey), satisfaction with health care decision (Satisfaction With Decision Scale), and satisfaction with office visit; surveys were completed at baseline (visit 1), at surgery (visit 2), and after surgery (visit 3). MAIN OUTCOME MEASURES: Short-term changes in QOL before surgery (visit 1 to visit 2) and after surgery (visit 2 to visit 3). RESULTS: Changes in QOL before surgery were mostly trivial, and were smaller than changes observed after surgery (P<.001). Large, moderate, and small improvements in QOL occurred after surgery in 56%, 15%, and 8% of children, respectively. Physical symptoms, caregiver concerns, emotional distress, and hearing loss were most improved, but significant changes were also seen for activity limitations and speech impairment. Trivial changes occurred in 17% of children, and 4% had poorer QOL. Predictors of poorer QOL were otorrhea 3 or more days (10% of variance) and decreased satisfaction with surgical decision (3% of variance). Hearing status, child age, type of otitis media (recurrent vs chronic), and office visit satisfaction were unrelated to outcome. CONCLUSIONS: Tympanostomy tubes produce large short-term improvements in QOL for most children. The best outcomes occur when postoperative otorrhea is absent or minimal, and when parents are satisfied with their initial decision to have surgery. Further research is needed to document the long-term impact of tubes on child QOL.

Retropharyngeal abscess management in children: current practices.

Retropharyngeal abscesses (RAs) in children are uncommon in the modern antibiotic era. As a result, there are few large series outlining the management of these infections in contemporary literature. The goal of this study is to determine the current standard of care for RA. The membership of the American Society of Pediatric Otolaryngology was surveyed, and the response rate was 77.5%. Seventy-two percent of practitioners reported that CT is their preferred diagnostic method. Nearly two thirds recommended a trial of intravenous antibiotics at least occasionally for suspected RA before operative drainage was considered; 51% of respondents indicated that 20% to 40% of RA may resolve with antibiotics alone. Intraoral incision and drainage is the surgical technique preferred by 83% of respondents. Tracheotomy and short-term intubation (24 to 72 hours) are rarely required. This study defines current management practices for RA in children among pediatric otolaryngologists. Results are compared with those in the existing literature.

Fungal malignant otitis externa due to Scedosporium apiospermum.

Malignant otitis externa (MOE) is an infection of the external auditory canal that invades the skull base. Aspergillus species fungi were the pathological organism in 21 of 23 reported cases of fungal MOE. We report on a 21-year-old man with end-stage acquired immunodeficiency syndrome (AIDS) and fungal MOE caused by Scedosporium apiospermum. Fungal MOE is most common in patients with end-stage AIDS and hematologic malignancies. Granulation tissue is not a common finding in these patients, and the infectious process often starts in the mastoid air cells or middle ear space, as opposed to the external auditory canal. Surgical debridement and amphotericin B are the mainstays of therapy; resolution of the infection depends greatly on the severity of the underlying disease.

Isolated large vestibular aqueduct syndrome in a family.

This paper presents the second case in the literature of large vestibular aqueduct syndrome without associated cochlear anomalies in 2 members of the same family. The syndrome is frequently associated with sensorineural hearing loss presenting in childhood. The onset is commonly sudden, following an event causing increased intracranial pressure. On the basis of an emerging pattern of inheritance, we recommend screening siblings of an affected child. We also discuss the importance of characterizing the extent of disease of the inner ear.

Oral fluid intake following tonsillectomy.

Children undergoing tonsillectomy surgery traditionally have been required to drink a specified amount of fluid before being discharged home. With increasing economic pressures, same-day discharge tonsillectomy has become common, and several studies have shown it to be safe for the appropriately selected child. To examine the role of required oral fluid intake following tonsillectomy, a non-randomized cohort study was performed with 200 consecutive tonsillectomy patients scheduled for same-day discharge. The first 100 patients (group 1) were required to drink 20 cc/kg prior to discharge, and the next 100 patients (group 2) were not required to drink. The mean oral fluid intake prior to discharge decreased significantly between the two groups from 524 cc in group 1 to 130 cc in group 2 (P = 0.0001). The mean length of stay also decreased significantly from 13.8 h for group 1 to 10.0 h for group 2 (P = 0.0001). Sixty percent of children in each group vomited at least once following surgery. Fewer children in group 2 had protracted vomiting (8 versus 15) although this was not statistically significant (P = 0.12). No children were readmitted to the hospital for dehydration following discharge. Overall, 71% of children in group 1 scheduled to go home the same day were discharged on time, compared to 94% of children in group 2. In conclusion, it is safe and economically efficient to discharge tonsillectomy patients home prior to the resumption of normal oral fluid intake.

Ankyloglossia: controversies in management.

PURPOSE: To determine current beliefs regarding ankyloglossia and its treatment. DESIGN: Anonymous written survey. PARTICIPANTS: Otolaryngologists (OTO, n=423), pediatricians (PD, n=425), speech pathologists (SP, n=400), and lactation consultants (LC, n=350) were randomly selected from professional membership lists, with a response rate of 209 (49%), 235 (55%), 150 (37.5%), and 203 (58%), respectively. CLINICAL FINDINGS: Sixty-nine percent of LCs, but a minority of physician respondents, believe tongue-tie is frequently associated with feeding problems. Sixty percent of OTOs, 50% of SPs, but only 23% of PDs believe tongue-tie is at least sometimes associated with speech difficulties. Sixty-seven percent of OTOs versus 21% of PDs believe tongue-tie is at least sometimes associated with social/mechanical issues. Surgery is recommended at least sometimes for feeding, speech, and social/mechanical issues by 53, 74, and 69% of OTOs, respectively, but by only 21%, 29%, and 19% of PDs. CONCLUSION: The significance of ankyloglossia in children remains controversial, both within, and between, specialty groups.

Volunteer-based universal newborn hearing screening program.

OBJECTIVE: To evaluate efficacy and costs of a volunteer-based universal newborn hearing screening program. METHODS: The Lucile Packard Children's Hospital at Stanford newborn hearing screening program database was reviewed. Results and costs of the hearing screens were analyzed. RESULTS: Hearing screens were performed on 5771 newborns treated in the well-baby nursery and nine infants from this population were identified with hearing loss, seven of whom had no risks factors for hearing loss. Using volunteers to perform the first-line screen with the automated auditory brainstem response (AABR) technology, 91% of infants registered for screening were evaluated prior to discharge. An additional 4% of infants were screened as outpatients. If an infant failed the AABR on two occasions, he or she was rescreened with the AABR or transient evoked otoacoustic emissions by a licensed audiologist, often while the infant was still in the hospital. Using this algorithm, 5% of infants tested in the well-baby nursery needed additional follow-up as an outpatient. Cost analysis of this volunteer-based program reveals a per/baby screening cost of $27.41. CONCLUSIONS: A volunteer-based hearing screening program is a viable option for hearing screening in well-baby nurseries but does not result in significant cost savings during the first 2 years of the program.

Pitfalls in the diagnosis of aerodigestive tract foreign bodies.

In the young child, particularly those between the ages of 1 and 3 years, aerodigestive tract foreign bodies continue to be a significant problem. Early diagnosis and treatment can decrease morbidity and length of hospital stay in these children. Three cases of delayed diagnosis in children with bronchial (2) and esophageal (1) foreign bodies are presented. In dealing with young children it is important to maintain a high clinical suspicion of a foreign body and to perform a detailed history and physical examination. Options in radiographic analysis of the patient with a suspected foreign body, probable locations of the foreign body, and the likelihood of definitive radiographic findings are discussed. Importantly, a negative radiographic analysis does not rule out the presence of an aerodigestive tract foreign body. Two flow charts for the evaluation of patients who have possibly ingested or inhaled a foreign body are presented to aid the primary care physician in diagnosis.

[In vitro and in vivo investigations of a modified textile keratoprosthesis. ACTO TexKPRO]. / In-vitro- und In-vivo-Untersuchung einer modifizierten textilen Keratoprothese. ACTO TexKPRO.

BACKGROUND: Clinical application of a keratoprosthesis (KPRO) is still a challenging task. Recent developments reflect the concepts of nut and bolt, intrastromal implantation or an osteoodontokeratoprosthesis (OOKP). A new concept of a textile KPRO has been evaluated in a limited human study with considerable difficulties which after termination of the study and considerable improvements was restarted using animal experiments. MATERIALS: The ACTO TexKPRO is made from polyvinylidene difluoride (PVDF) fibers and transparent silicone. The first and second developmental stages differed in density and size of fibers and furthermore in surface modifications of the fibers and optics which were improved for the second prototype. METHODS: Implantation of the prosthesis was performed in four patients with corneal blindness and in two cases retinal disease which required surgery. In the later animal experiments surgery was performed on three rabbits. Surgery was performed by redressing the conjunctiva, opening of the eyeball with a central 6.5 mm trephination, removal of the lens and iris and implantation and suturing of the TexKPRO. If required a silicone oil endotamponade was placed. RESULTS: All eyes were stable with the keratoprosthesis. The first prototype showed conjunctival recession on the textile haptics with highly susceptible endopthalmitis risk due to infection of the PVDF so that we decided to remove the prosthesis from all eyes after one case of severe endophthalmitis occurred. The longest time of placement was 40 months and the shortest time 6 months. All eyes were restored by keratoplasty. In animals with the new haptic we found better conjunctivalization and stable implantation of the KPRO. DISCUSSION: The textile KPRO provides a stable implantation procedure and safe connection of fibers to the scleral wound bed. The optical and mechanical implantation is safe and stable. Surface epithelialization is improved with the new surface modifications and different PVDF fiber density but beforel new implantations are planned further conceptual changes will be introduced.