[Treatment of Osteochondral Lesions in the Ankle: A Guideline from the Group "Clinical Tissue Regeneration" of the German Society of Orthopaedics and Traumatology (DGOU)]. / Behandlung osteochondraler Läsionen des Sprunggelenks: Empfehlungen der Arbeitsgemeinschaft Klinische Geweberegeneration der DGOU.

Background: Osteochondral lesions (OCL) of the ankle are a common cause of ankle pain. Although the precise pathophysiology has not been fully elucidated, it can be assumed that a variety of factors are responsible, mainly including traumatic events such as ankle sprains. Advances in arthroscopy and imaging techniques, in particular magnetic resonance imaging (MRI), have improved the possibilities for the diagnosis of OCLs of the ankle. Moreover, these technologies aim at developing new classification systems and modern treatment strategies. Material and Methods: This article is a review of the literature. Recommendations of the group "Clinical Tissue Regeneration" of the German Society of Orthopaedics and Traumatology (DGOU) for the treatment of OCLs of the ankle are presented. The review gives a concise overview on the results of clinical studies and discusses advantages and disadvantages of different treatment strategies. Results: Non-operative treatment shows good results for selected indications in children and adolescents, especially in early stages of osteochondritis dissecans (OCD). However, surgical treatment is usually indicated in OCLs in adolescents and adults, depending on the size and location of the lesion. Various arthroscopic and open procedures are frequently employed, including reattachment of the fragment, local debridement of the lesion with fragment removal and curettage of the lesion, bone marrow-stimulation by microfracture or microdrilling (antegrade or retrograde), and autologous matrix-induced chondrogenesis (AMIC®) - with or without reconstruction of a subchondral bone defect or cyst by autologous cancellous bone grafting. Isolated subchondral cysts with an intact cartilage surface can be treated by retrograde drilling and possibly additional retrograde bone grafting. For larger defects or as salvage procedure, osteochondral cylinder transplantation (OATS® or Mosaicplasty®) or matrix-induced autologous chondrocyte transplantation (MACT) are recommended. Transplantation of so-called (osteochondral) mega grafts, such as autologous bone grafts or allografts, are used for very large osteochondral defects that cannot be reconstructed otherwise. Implantation of the so-called "small metal implants" - such as HemiCAP Talus® - is reserved for selected cases after failed primary reconstruction. Corrective osteotomies are indicated in accompanying axial malalignments. Conclusions: There are several different treatment strategies for OCLs, but clinical studies are rare and evidence is limited. Therefore, interventional studies, e.g. randomised controlled trials (RCTs), but also observational studies, e.g. based on data of the Cartilage Registry of the German Society of Orthopaedics and Traumatology (www.knorpelregister-dgou.de), are needed and are recommended by the authors.

Periodontal ligament cells as alternative source for cell-based therapy of tendon injuries: in vivo study of full-size Achilles tendon defect in a rat model.

Tendon's natural healing potential is extremely low and inefficient, with significant dysfunction and disability due to hypocellularity and hypovascularity of tendon tissues. The application of stem cells can aid in significantly enhanced repair of tendon rupture; therefore, the main aim of this study is to assess the potential of using periodontal ligament cells (PDL), usually obtained from patients undergoing orthodontic treatment, as a novel cell source for cell-based therapy for tendon injuries in a clinically relevant rat full-size Achilles tendon defect. In addition, the study compares the differences between the healing effects of Achilles tendon-derived cells (AT) versus PDL and, hence, comprises of four experimental groups, native tendon (NT), empty defect (ED), PDL and human AT (hAT). The tendon healing in each group was assessed in the late remodelling phase at 16 weeks after surgery using a combination of methods, including evaluation of gross morphological appearance; various histological and immunohistological stainings; and detailed analyses of cell morphometry. Based on these outcome measures, PDL cell-implanted tendons exhibited not only advanced tissue maturation, less ectopic fibrocartilage formation, more organised collagen fibres, tendon matrix expression corresponding to the final healing stage, and better cell-morphometry parameters when compared with the ED group, but were also very similar to the tendons treated with hAT-derived cells. Taken together, our study clearly demonstrates the feasibility of using PDL cells as a novel cell source for tendon repair and strongly recommends this cell type for the future development of innovative regenerative applications for treatment of different tendon or ligament pathologies.

Autologous chondrocyte implantation (ACI) for cartilage defects of the knee: A guideline by the working group "Clinical Tissue Regeneration" of the German Society of Orthopaedics and Trauma (DGOU).

BACKGROUND: Autologous chondrocyte implantation (ACI) is an established and well-accepted procedure for the treatment of localised full-thickness cartilage defects of the knee. METHODS: The present review of the working group "Clinical Tissue Regeneration" of the German Society of Orthopaedics and Trauma (DGOU) describes the biology and function of healthy articular cartilage, the present state of knowledge concerning therapeutic consequences of primary cartilage lesions and the suitable indication for ACI. RESULTS: Based on best available scientific evidence, an indication for ACI is given for symptomatic cartilage defects starting from defect sizes of more than three to four square centimetres; in the case of young and active sports patients at 2.5cm(2), while advanced degenerative joint disease needs to be considered as the most important contraindication. CONCLUSION: The present review gives a concise overview on important scientific background and the results of clinical studies and discusses the advantages and disadvantages of ACI. LEVEL OF EVIDENCE: Non-systematic Review.

[Clinical management of rotator cuff tears. Current concepts in cell-based therapy strategies]. / Klinische Versorgung von Rupturen der Rotatorenmanschette. Aktueller Stand der Zelltherapie.

Due to the increasing demand for functionality in an aging yet physically active society, the treatment of rotator cuff tears is of ever-growing importance. Despite intensive research efforts, the treatment of degenerative rotator cuff tears, in particular their long-term outcome, is still a challenge. While in recent years the focus was on biomechanics and the technical aspects of rotator cuff reconstruction, attention has now turned to the biological considerations of tendon regeneration. This article highlights the current state of biological rotator cuff augmentation in a clinical setting and provides an insight into and an outlook on the experimental procedures.

[The German Cartilage Registry (KnorpelRegister DGOU) for evaluation of surgical treatment for cartilage defects: experience after six months including first demographic data]. / Das KnorpelRegister DGOU zur Erfassung von Behandlungsergebnissen nach Knorpeloperationen: Erfahrungen nach 6 Monaten und erste epidemiologische Daten.

The German Cartilage Registry (KnorpelRegister DGOU) has been introduced in October 2013 and aims on the evaluation of patients who underwent cartilage repair for symptomatic cartilage defects. It represents a nation-wide cohort study which has been introduced by the working group "Tissue Regeneration" of the Germany Society of Orthopaedic Surgery and Traumatology and is technically based upon a web-based remote data entry (RDE) system. The present article describes first experiences with the registry including patient and treatment characteristics. Between October 2013 and April 2014, a total of 230 patients who had undergone surgical cartilage repair for symptomatic full-thickness cartilage defects of the knee has been included in the German Cartilage Registry from 23 cartilage repair centres. Mean age was 37.11 years (SD 13.61) and mean defect size was 3.68 cm(2) (SD 0.23). Since the introduction of the KnorpelRegister DGOU the total number of registered patients has increased steadily up to the most recent figure of 72 patients within one month. Patients were treated mainly according to the recommended therapies. The highest percentage in therapy is represented by the bone marrow stimulation techniques (55.02 %) as well as by the autologous chondrocyte transplantation (34.92 %). Unlike the patient collective in the majority of prospective randomised controlled trials, the patient population within the registry shows a high proportion of patients with accompanying pathologies, with an age of more than 50 years at the time of treatment and with unfavourably assessed accompanying pathologies such as an affection of the opposite cartilage surface or a previously resected meniscus. In summary, the technical platform and forms of documentation of the KnorpelRegister DGOU have proved to be very promising within the first six months. Unlike data from other clinical trials, the previous analysis of the patients' data and therapies reflects successfully the actual medical care situation of patients with cartilage defects of the knee joint. This analysis also provides new information on subgroups of patients that have not yet been recorded in the scientific literature. This will be part of the first analysis of clinical treatment data. An expansion of the KnorpelRegister DGOU to patients with cartilage defects of the ankle and hip joints is already decided upon and initialised.

Topographic deformation patterns of knee cartilage after exercises with high knee flexion: an in vivo 3D MRI study using voxel-based analysis at 3T.

OBJECTIVES: To implement a novel voxel-based technique to identify statistically significant local cartilage deformation and analyze in-vivo topographic knee cartilage deformation patterns using a voxel-based thickness map approach for high-flexion postures. METHODS: Sagittal 3T 3D-T1w-FLASH-WE-sequences of 10 healthy knees were acquired before and immediately after loading (kneeling/squatting/heel sitting/knee bends). After cartilage segmentation, 3D-reconstruction and 3D-registration, colour-coded deformation maps were generated by voxel-based subtraction of loaded from unloaded datasets to visualize cartilage thickness changes in all knee compartments. RESULTS: Compression areas were found bifocal at the peripheral medial/caudolateral patella, both posterior femoral condyles and both anterior/central tibiae. Local cartilage thickening were found adjacent to the compression areas. Significant local strain ranged from +13 to -15 %. Changes were most pronounced after squatting, least after knee bends. Shape and location of deformation areas varied slightly with the loading paradigm, but followed a similar pattern consistent between different individuals. CONCLUSIONS: Voxel-based deformation maps identify individual in-vivo load-specific and posture-associated strain distribution in the articular cartilage. The data facilitate understanding individual knee loading properties and contribute to improve biomechanical 3 models. They lay a base to investigate the relationship between cartilage degeneration patterns in common osteoarthritis and areas at risk of cartilage wear due to mechanical loading in work-related activities. KEY POINTS: • 3D MRI helps differentiate true knee-cartilage deformation from random measurement error • 3D MRI maps depict in vivo topographic distribution of cartilage deformation after loading • 3D MRI maps depict in vivo intensity of cartilage deformation after loading • Locating cartilage contact areas might aid differentiating common and work-related osteoarthritis.

[Experience with medial unicompartmental prostheses with a mobile plateau]. / Erfahrungen mit medialen monokondylären Prothesen mit mobilem Plateau.

BACKGROUND: Unicompartmental knee arthroplasty (UKA) has become an accepted therapy for medial osteoarthritis. The main reasons for its popularity are the minimally invasive surgical technique and the reports of excellent long-term results including high patient satisfaction and good knee joint function especially in younger patients. OBJECTIVES: The purpose of our retrospective study was to evaluate the physical activities of patients who had undergone an Oxford III medial UKA. Special attention was paid to implant positioning and osteoarthritis of the patellofemoral joint. MATERIALS AND METHODS: Of 181 implanted Oxford III prosthesis, 136 (75.1%) could be followed up. The mean age at time of surgery was 65.2 years; the average time of follow-up was 4.2 years. In addition to a physical examination and x-ray, the following scores were obtained: WOMAC (Western Ontario and McMaster Osteoarthritis Index), OKS (Oxford Knee Score), KSS (Knee Society Score), UCLA activity and the Turba score. RESULTS: The majority of the patients (81%) returned to their sporting activity following knee surgery. Higher complication rates or progression of osteoarthritis associated with sporting activities were not observed. The active patients had significantly higher scores for the OKS, KSS, WOMAC, and UCLA scores. The correct implant position, especially avoiding overcorrection to valgus malalignment, is important for good clinical outcome. CONCLUSION: Our results demonstrate that a high degree of patient satisfaction in terms of physical and sporting activity can be achieved using the Oxford III UKA for medial osteoarthritis without an increased risk for complications.

Tissue characteristics in tendon-to-bone healing change after rotator cuff repair using botulinumneurotoxin A for temporary paralysis of the supraspinatus muscle in rats.

We hypothesized that botulinumneurotoxin A (BoNtA) positively influences tissue characteristics at the re-insertion site when used as an adjuvant prior to rotator cuff repair. One hundred and sixty Sprague-Dawley rats were randomly assigned to either a BoNtA or saline-injected control group. BoNtA or saline solution was injected into the supraspinatus muscle one week prior to repair of an artificially created supraspinatus tendon defect. Post-operatively, one subgroup was immobilized using a cast on the operated shoulder while the other had immediate mobilization. Histologically, the fibrocartilage transition zone was more prominent and better organized in the BoNtA groups when compared to the saline control group. In the immediately mobilized BoNtA groups significantly more collagen 2 at the insertion was detected than in the control groups (p<0.05). Fiber orientation of all BoNtA groups was better organized and more perpendicular to the epiphysis compared with control groups. Tendon stiffness differed significantly (p<0.05) between casted BoNtA and casted saline groups. Tendon viscoelasticity was significantly higher (p<0.05) in the immobilized saline groups no matter if repaired with increased or normal repair load. The results of this study suggest that reduction of load at the healing tendon-to-bone interface leads to improved repair tissue properties.

[Post-treatment rehabilitation after autologous chondrocyte implantation: State of the art and recommendations of the Clinical Tissue Regeneration Study Group of the German Society for Accident Surgery and the German Society for Orthopedics and Orthopedic Surgery]. / Nachbehandlung bei der autologen Chondrozytentransplantation: Eine Bestandsaufnahme und Empfehlung der AG Klinische Geweberegeneration der DGU/DGOOC.

BACKGROUND: Over the course of the past two decades autologous chondrocyte implantation (ACI) has become an important surgical technique for treating large cartilage defects. The original method using a periostal flap has been improved by using cell-seeded scaffolds for implantation, the matrix-based autologous chondrocyte implantation (mb-ACI) procedure. MATERIAL AND METHODS: Uniform nationwide guidelines for post-ACI rehabilitation do not exist. A survey was conducted among the members of the clinical tissue regeneration study group concerning the current rehabilitation protocols and the members of the study group published recommendations for postoperative rehabilitation and treatment after ACI based on the results of this survey. RESULTS: There was agreement on fundamentals concerning a location-specific rehabilitation protocol (femoral condyle vs. patellofemoral joint). With regard to weight bearing and range of motion a variety of different protocols exist. Similar to this total agreement on the role of magnetic resonance imaging (MRI) for postsurgical care was found but again a great variety of different protocols exist. CONCLUSIONS: This manuscript summarizes the recommendations of the members of the German clinical tissue regeneration study group on postsurgical rehabilitation and MRI assessment after ACI (level IVb/EBM).

[Autologous chondrocyte implantation (ACI) for cartilage defects of the knee: a guideline by the working group "Tissue Regeneration" of the German Society of Orthopaedic Surgery and Traumatology (DGOU)]. / Stellenwert der autologen Chondrozytentransplantation (ACT) in der Behandlung von Knorpelschäden des Kniegelenks - Empfehlungen der AG Klinische Geweberegeneration der DGOU.

Autologous chondrocyte transplantation/implantation (ACT/ACI) is an established and recognised procedure for the treatment of localised full-thickness cartilage defects of the knee. The present review of the working group "Clinical Tissue Regeneration" of the German Society of Orthopaedics and Traumatology (DGOU) describes the biology and function of healthy articular cartilage, the present state of knowledge concerning potential consequences of primary cartilage lesions and the suitable indication for ACI. Based on current evidence, an indication for ACI is given for symptomatic cartilage defects starting from defect sizes of more than 3-4 cm2; in the case of young and active sports patients at 2.5 cm2. Advanced degenerative joint disease is the single most important contraindication. The review gives a concise overview on important scientific background, the results of clinical studies and discusses advantages and disadvantages of ACI.

Comparison of tenocytes and mesenchymal stem cells seeded on biodegradable scaffolds in a full-size tendon defect model.

In order to investigate cell-based tendon regeneration, a tendon rupture was simulated by utilizing a critical full-size model in female rat achilles tendons. For bridging the defect, polyglycol acid (PGA) and collagen type I scaffolds were used and fixed with a frame suture to ensure postoperatively a functional continuity. Scaffolds were seeded with mesenchymal stem cells (MSC) or tenocytes derived from male animals, while control groups were left without cells. After a healing period of 16 weeks, biomechanical, PCR, histologic, and electron microscopic analyses of the regenerates were performed. Genomic PCR for male-specific gene was used to detect transplanted cells in the regenerates. After 16 weeks, central ossification and tendon-like tissue in the superficial tendon layers were observed in all study groups. Biomechanical test showed that samples loaded with tenocytes had significantly better failure strength/cross-section ratio (P < 0.01) compared to MSC and the control groups whereas maximum failure strength was similar in all groups. Thus, we concluded that the application of tenocytes improves the outcome in this model concerning the grade of ossification and the mechanical properties in comparison to the use of MSC or just scaffold materials.

[Locoregional deformation pattern of the patellar cartilage after different loading types - high-resolution 3D-MRI volumetry at 3 T in-vivo]. / Lokoregionäre Deformationsmuster im Patellarknorpel nach unterschiedlichen Belastungsparadigmen - hochauflösende 3-D-MR-Volumetrie bei 3 T in vivo.

PURPOSE: To analyze locoregional deformation patterns indicative of contact areas in patellar cartilage after different loading exercises. MATERIALS AND METHODS: 7 healthy patellae were examined in-vivo before and immediately after standardized loading (kneeling, squatting or knee bends) and after 90 minutes of rest using a sagittal 3D-T1-w FLASH WE sequence (22 msec/ 9.8 msec/ 15°/ 0.3 × 0.3 × 1.5 mm³) at 3 T. After cartilage segmentation and 3D reconstruction, voxel-based and global precision errors (PR) were calculated. The former were used to determine significant differences in local cartilage thickness. Voxel-based 2σ-thickness difference maps were calculated to visualize locoregional deformation patterns. Global changes in volume (Vol), mean thickness (mTh) and cartilage-bone-interface area (CBIA) were calculated. RESULTS: The voxel-based PR depended on cartilage thickness (D) ranging from 0.12 - 0.35 mm. For D ≥ 1 mm the RF was < 0.31 mm (< voxel size), and for D ≥ 2 mm, the RF was < 0.22 mm. The global PR was 83 mm³ (2.4 %) for Vol, 0.06 mm (2.0 %) for mTh and 16 mm² (1.4 %) for CBIA. The focal cartilage deformation equaled 14 % of the local thickness reduction. The deformation areas were oval and located in the peripheral medial (more vertically oriented, all exercises) and caudo-lateral (more horizontally oriented, kneeling and knee bends) aspects of the patella and were least pronounced in knee bends. Significant changes for Vol/mTh ranged from 2.1 to 3.7 %. CONCLUSION: This MRI-based study is the first to identify in-vivo voxel-based patellar cartilage deformation patterns indicating contact and loading zones after kneeling and squatting. These zones are anatomically and functionally plausible and may represent areas where stress induced degeneration and subsequent OA can originate. The data may facilitate understanding of individual knee loading properties and help to improve and validate biomechanical models for the knee.

Crosslinked polyethylene in knee arthroplasty: a simulator study evaluating the positive influence on the tribocontact area in the fixed-bearing knee.

BACKGROUND: Crosslinked polyethylene (XPE) was developed to reduce the wear rate in hip as well as knee arthroplasty. The crosslinking process reduces the mechanical properties of ultra-high-molecular-weight polyethylene (UHMWPE), particularly its fatigue strength. UHMWPE fatigue occurs more frequently in the knee than in the hip joint due to its changing tribocontact areas (TCAs) combined with high weight bearing. This is why XPE is still controversially discussed for use in total knee arthroplasty. Therefore, the potential advantage of using XPE in the knee was analysed in a simulator study with a focus on potential fatigue wear mechanisms. METHODS: Three different kinds of XPE and one conventional UHMWPE were tested over 5 million cycles in fixed-bearing knee designs. The TCAs were examined by replicas, and their extent was measured. The wear mechanism was analysed by scanning electron microscopy. RESULTS: The extent of the TCAs was less than 5% for all XPEs, whereas 35% for the conventional UHMWPE. Fatigue wear mechanisms were not observed. CONCLUSION: The measured small extent of the TCAs as a predictor of a low wear rate without any fatigue wear mechanism shows a possible advantage for the use of XPE even in knee arthroplasty.

The influence of adjuvants on local recurrence rate in giant cell tumour of the bone.

INTRODUCTION: Intralesional surgery of giant cell tumour of the bone (GCT) may result in a high rate of local recurrence. The introduction of local adjuvants, such as cementation, cryosurgery or phenolization, has proved to be successful in the reduction of recurrence rates. This study presents the results of a single institution in surgery of GCT with an evolution in treatment strategies. MATERIAL & METHODS: Forty primary and 25 recurrent surgical procedures in 46 patients with GCT of the bone with a median follow-up of 72 months were reviewed retrospectively. The mean age was 32.6 years (range 13.6-57.9 years). Forty-seven curettages and 18 resections were performed. For the curettages, a large bone window was cut followed by high speed burring and bone grafting or cementation. In 34 of 47 curettages and 7 of 18 resections, phenol was additionally applied. RESULTS: Two patients showed pulmonary metastasis, one died due to metastatic disease. In total, a third of the patients developed local recurrence (32.3%). This was evenly spread among primary and recurrent diesease (32.5% vs. 32%). Seven of 13 curettages without adjuvant recurred (53.9%), compared to 11 of 34 curettages with adjuvant phenol (32.4%). Three of 18 resections developed a recurrence (16.7%). No complications in respect to the use of phenol were seen. DISCUSSION: Phenolization is a safe local adjuvant therapy for GCT. Although the recurrence rate was lower with the use of phenol, this drop was not significant. The comparable high recurrence rate in our study, even if phenol was used, might be due to the fact that curettage was our favoured treatment, even in cases with an extensive juxta-articular tumour. We recommend adjuvant phenolization in the treatment of GCT of the bone after thorough curettage in applicable cases, including where cementation is used for defect filling.

[The dislocated shoulder prosthesis--an avoidable disaster?]. / Die luxierte Schulterprothese--eine vermeidbare Katastrophe?

Instability after shoulder arthroplasty is a common problem, even though complete dislocations are rare. A distinction can be made between vertical and horizontal instabilities. The most common type of vertical instability is superior migration of the humeral head caused by rotator cuff insufficiency; the shoulder prosthesis should be changed for an inverse prosthesis if the patient is symptomatic. Horizontal instabilities can certainly lead to acute dislocation, but it is far more common for them to result in eccentric loading of the glenoid and in turn to increased wear and loosening. When a prosthesis is first implanted it is essential to reproduce the original bony situation before the deformity caused by arthrosis, arthritis or fracture, as this is the only way to prevent instability. This requires careful preoperative planning including evaluation of CT or MRI scans so that during the operation it will be possible, for example, to reorientate an eccentrically torn glenoid using a bone graft or by eccentric reaming and restore the original torsion. At least as much importance attaches to the treatment of the soft tissue, meaning careful release and later closure of the rotator cuff and capsule complex, as to the bony situation. In the authors' own institution 190 prostheses were implanted between 2000 and 2006 and there were three dislocations (1.6%).

[Hip dislocation following THA]. / Hüftluxation nach Hüftgelenktotalendoprothesenimplantation.

In the event of a hip dislocation following THA analysis of its mechanism is the main priority. In addition, the time since the operation and the direction of the dislocation need to be taken into account. When the cause of the dislocation is analysed the formation of the neocapsule plays a part at least in the case of early dislocations (within the first 6 weeks after the operation). Most dislocations happen during this postoperative period, and these can usually be treated nonoperatively by closed reduction with only a short period of general anaesthesia. Late dislocations (in the 7th and subsequent postoperative week) generally occur because of malpositioning or migration of the components of the prosthesis and quite often do need operative treatment. Dislocation after implantation of a total hip replacement is a serious complication; it should be treated quickly, and initially it confronts the operator with many unanswered questions, from the causes to their treatment.

[Prognostic factors to assess the value of arthroscopy in gonarthrosis]. / Prognostische Faktoren zur Beurteilung der Wertigkeit der ASK bei Gonarthrose.

AIM: The value of athroscopy in osteoarthritis(oa) of the knee remains uncertain. Many studies claim to prove efficacy of arthroscopy in oa of the knee, while other authors report that there is no such effect. The purpose of this study was to identify factors to predict the outcome of arthroscopy in oa of the knee. METHOD: The modified Lysholm score was used to assess the outcome of arthroscopy in 49 patients after a follow up of 2.5 yrs. This was a retrospective outcome study. RESULTS: No correlation between modified Lysholm score and patient age and gender could be detected. There were significantly better outcomes in the group of patient with no deviation of axis and in the group of patients which did not show a progression of oa of the knee in the radiographs during follow-up. Even if the patients had more severe osteoarthritis. CONCLUSION: Patient selection is an important factor for a good outcome after arthroscopy in older patients with oa of the knee. Deviation of the axis and the "activity" of the osteoarthritis at the time of surgery are predictors for outcome. There is the need to establish diagnostic tools to measure the "activity" of oa of the knee before surgery.

[Clinical aspects of retinopathy of prematurity. Results following diode laser coagulation]. / Klinische Aspekte bei Frühgeborenen-Retinopathie (ROP). Ergebnisse nach Dioden-Laserkoagulation.

Retinopathy of prematurity (ROP) represents a disease of the immature retina of preterm infants due to irregular vascularisation. The present article gives information about different parameters of the newborns (gestational age, birth weight, need of oxygen, stage of ROP) and shows the results concerning anatomical and functional aspects following diode laser treatment in 61 prematurely born babies, diagnosed and treated in a period of 5S years in the Hospital of the Ludwig Maximilians University. The mean +/- SD gestational age was 24.9 (+/- 1.59) weeks, the mean +/- SD birth weight was 683 (+/- 174) grams. Diode laser treatment was performed at a mean +/- SD age of 36.14 (+/- 2.04) weeks. Stage 3 retinopathy with "plus disease" was diagnosed in 95.5 % of the infants. In comparison to term born babies or preterm infants without ROP, the diode laser-treated newborns showed a higher incidence of myopia (59 %). An unfavourable outcome in term of the anatomic situation was seen in 9.8 % of these babies.

Systemic vs local administration of delta-aminolevulinic acid for laparoscopic fluorescence diagnosis of malignant intra-abdominal tumors. Experimental study.

BACKGROUND: Administration of delta-aminolevulinic acid (ALA) either systemically or locally results in tumor-specific accumulation of protoporphyrin IX (PpIX). When excited with light at a defined wavelength and viewed with the appropriate filter cells containing PpIX, have a characteristic red fluorescence. We evaluated both locally (intraperitoneally [i.p.]) and systemically (intravenously [i.v.]) administered ALA to compare its effectiveness for laparoscopic fluorescent visualization of intraperitoneal tumors. METHODS: Peritoneal carcinosis was induced in rats using colon carcinoma cells (CC531). Photosensitization was achieved either by intravenous (i.v. group) or intraperitoneal (i.p. group) application of ALA solution. Staging laparoscopy was performed in both groups, first using conventional white light and subsequently using blue light (380-440 nm) to excite PpIX-induced fluorescence. RESULTS: Conventional white light laparoscopy showed 142 visible intraperitoneal tumor foci in the i.p. group and 116 such foci in the i.v. group. In the i.p. group, all tumors (100%) also were fluorescence positive, whereas in the i.v. group only 32 of the tumors (28%) showed the typical red fluorescence. In the i.p. group, 30 additional tumors were detected by fluorescence excitation (21%), as compared with eight additional tumors in the i.v. group (7%). CONCLUSIONS: Fluorescence laparoscopy after local (i.p.) photosensitization with ALA is a more reliable and effective method than systemic (i.v.) photosensitization for the detection of small or occult i.p. tumors.