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Purpose: The purpose of this study was to compare the aqueous humor outflow using three type of implants after deep sclerectomy. A numeric imaging system with ICG and fluorescein angiography was used. The evolution over time was recorded, while filtration and outflow facility were measured. Material and Methods: Numeric imaging system with ICG and fluorescein angiography were performed before and after deep sclerectomy at regular intervals after surgery. Both resorbable (collagen) and non-resorbable (hema) intrascleral devices have been tested in eight rabbits. The resorbtion time of the collagen implants has been monitored using UBM technique. The outflow facility was measured with the technique of anterior chamber canulation and constant pressure method. Results: The resorbable collagen implants could be observed with UBM and angiography during the first six weeks postoperatively. The image of the non-resorbable Hema implant remained clearly visible over time. New drainage vessels were observed around the filtering bleb. The filtration significantly increased as the outflow facility improved after surgery, while the intraocular pressure remained stable over time. Conclusion: This conjunction of UBM, angiography and outflow measurement allowed us to study and compare three types of implants used as space maintainer after deep sclerectomy, and analyse their effect on the aqueous filtration and outflow facility.

Hintergrund Zuweilen besteht bei glaukomatosen Patienten, die einer Trabekulektomie unterzogen worden waren, keine Korrelation zwischen dem Erscheinungsbild des Filterkissens und dem Augeninnendruck. Da die Ultraschallbiomikroskopie eine hohe Auflosung der Strukturen des vorderen Augensegments erlaubt, wurden mit ihr Filterkissen von Patienten untersucht, die einer Trabekulektomie unterzogen worden waren. Patienten und Methoden Bei 46 Augen von 46 Patienten wurde nach Trabekulektomie eine Ultraschallbiomikroskopie (50 Mhz) des Filterkissens durchgefuhrt. In zwei Gruppen mit einem postoperativen Augeninnendruck kleiner oder groser als 16 mmHg wurden Hohe des Filterkissens, Darstellbarkeit des Skleralappens und Binnenstruktur verglichen. Ergebnisse Es war moglich, longitudinale und transversale Schnitte der Filterkissen zu erhalten und deren Hohe, Struktur und Reflektivitat zu bestimmen. Filterkissen mit niedriger Reflektivitat und einem gut darstellbaren Skleralappen waren mit einem niedrigen postoperativen Augeninnendruck korreliert, wahrend die Hohe des Filterkissens keinen Zusammenhang mit dem postoperativen Augeninnendruck erkennen lies. Schlusfolgerungen Die Ultraschallbiomikroskopie ermoglicht eine prazise In-vivo-Darstellung des Filterkissens, erlaubt Ruckschlusse auf Mechanismen, die der Filtration von Filterkissen zugrunde liegen. Background Sometimes in glaucomatous patients treated with trabeculectomy there is not a correlation between bleb shape and intraocular pressure. So we studied the functional anatomy of the filtering bleb by a ultrasound biomicroscope, using high frequency (50 Mhz) probe, which provides high resolution images of filtering blebs. Materials and Methods A total of 46 filtering blebs of 46 patients after trabeculectomy were analyzed by ultrasound biomicroscopy (50 Mhz). Dimensions, shapes and structure of blebs were evaluated in 2 groups of patients. Results It was possible to obtain longitudinal or transverse images of filtering blebs, to measure the height, to evaluate the reflectivity inside and to follow the route under the scleral flap. Blebs with lower reflectivity and a visible route under the scleral flap had a lower intraocular pressure while the height was not important for a good intraocular pressure. Conclusions So ultrasound biomicroscopy can be a useful method to study filtering blebs and also to explain the mechanisms of filtering structures in patients who underwent trabeculectomy.

Background : Needling may become necessary when filtering blebs fail due to scarring or encapsulation. Our goal was to calculate the medium term success rate of the needling procedure. Methods : The results of 90 needling procedures performed on 58 eyes were analyzed. 52 eyes required one single needling (group 1) after simple trabeculectomy, whereas 19 eyes had to have double needling (group 2) and 3 eyes had to be needled 3 times (group 3). These figures do not include a 4th group of eyes which had been needled after repeated and complicated surgery. Success rates were calculated at t 1 = 0-1 day, t 2 = 1-4 weeks, t 3 = 4-8 weeks, t 4 = 3-5 months and t 5 =>6 months after the treatment. Results : The mean lOP (n = 90) was 29 ± 6 mm Hg preoperatively, 15 ± 10 10 mmHg at t 1 , 23 ± 9 mmHg at t2, 20 ± 7 mm Hg at t3, 17 ± 5 at and 17 ± 3 at t 5 . The overall success rates were 80% (t 1 ), 45% (t 2 ), 37% (t 3 ), 35% (t 4 ) and 31% (t 5 ). The corresponding success rates were 74%, 36%, 32%, 28% and 26% for group 1, 89%, 52%, 37%, 37% and 31% for group 2. 67% at all times for group 3 and 100%, 69%, 54%, 54% and 45% for group 4. Conclusions : In one third of all cases the needling is effective for more than 6 months. A complicated pressure lowering surgery does not necessarily diminish the effectiveness of a needling procedure. Re-needlings are as successful as the first one.

Background: Glaucoma is one of the most common causes of blindness in the world. This aspect is well known for the developed countries, however in Africa blindness mainly occurs due to cataract, trachoma and onchocercosis. Glaucoma is not mentioned enough. Patients present with severe findings after a long-lasting history of disease. Patients and Methods: In our project experienced surgeons and young medical doctors have been practising regularly in Cameroon since 2001. By means of support from the "Komitee zur Verhutung von Blindheit" and medical industries we keep in contact with a local ophthalmologist. During the consultation of hundreds of patients we have often seen highly advanced glaucoma cases. Results: The medical therapy of glaucoma and also the surgical procedures are limited - modern antiglaucomatosa are not available. We achieved sufficient regulation of intraocular pressure after trabeculectomy with or without cataract surgery in many cases. The success rate was decreased by severe scar reactions especially in young black people. In advanced glaucoma cases and oculus ultimus we also used the old techniques of iridencleisis. There was a good postoperative regulation of eye pressure, but sometimes we saw a giant filtering bleb after this iris-mutilating procedure. Conclusions: Glaucoma is a very complex problem, also in Cameroon. Although the diagnostic possibilities are limited, the therapeutic spectrum is differentiated. The introduction of a robust laser for cyclophotocoagulation would be a useful alternative.

In a review of 402 goniotrephinations the preoperative diagnosis was open-angle glucoma in 61%, chronic congestive glaucoma in 21%, acute glaucoma in 11%, secondary glaucoma in 5%, and juvenile glaucoma in 2%. In 77% of the eyes followed for periods of up to seven years IOP returned to normal. Supplementary local therapy or digital eyeball massage raised the percentage of eyes with normal pressure values to 92,8%. Visual acuity was maintained or improved in 76%. There was no case of visual field defect during the early postoperative period, and no correlation was found between the regulation of IOP and the condition of the filtering bleb. In 10,4% complications occurred during the early postoperative period and in 1% late complications were seen. In 45% of the secondary glaucoma cases and in three out of seven cases of buphthalmus IOP was normalized.

Bei Zustand nach filtrierender Glaukomoperation mit vorbestehendem Sickerkissen kann der Starschnitt zwecks Durchfuhrung einer Kataraktoperation entweder durch einen kornealen oder durch einen limbalen Schnitt erfolgen. Der korneale Schnitt vermeidet eine direkte chirurgische Traumatisierung des Filterkissens, wogegen das Filterkissen beim limbalen Schnitt in einem am Limbus haftenden Bindehautlappen freiprapariert wird. Der postoperative Verlauf nach diesen beiden Starschnittechniken wurde in einer kasuistischen Studie von je 25 Patienten bezuglich des Verhaltens von Augeninnendruck, Sickerkissen und Astigmatismus untersucht. Bezuglich Augeninnendruck und Filterkissen ergeben beide Starschnittechniken keine wesentlichen Unterschiede. Hingegen wies die Gruppe mit limbaler Schnittechnik deutlich weniger hohe Astigmatismuswerte auf als das Kollektiv mit kornealem Schnitt. Dies ist jedoch nicht Folge der Schnitt-, sondern der Nahttechnik. Following a filtering procedure for glaucoma in which a filtering bleb is present, the incision for cataract extraction can be made either corneally or limbally. With a corneal incision a direct surgical trauma to the filtering bleb can be avoided, whereas with a limbal incision the filtering bleb is excised free on a limbus-based conjunctival flap. The postoperative course following these two cataract incision techniques was observed in 25 patients each in a casuistic study with regard to the behavior of intraocular pressure, filtering blebs, and astigmatism. With regard to intraocular pressure and filtering blebs, there were no significant differences between the two techniques. On the other hand, the group treated with the limbal incision technique had distinctly lower astigmatism values than did the corneal incision group. In the authors' opinion this was, however not due to the incision technique but rather to the suturing technique.

After total excision of an excessively large filtering bleb extending to the cornea, the conjunctiva was dissected from the upper half of the eyeball and fixed by sutures into a step of the corneal periphery obtained by a keratectomy of 1 mm large strip of superficial cornea tissue along the upper half of the limbus. In 10 eyes operated on in this way -- and in seven of them over four years -- the newly developed filtrating bleb is flat and shows a well vascularised wall without any signs of degeneration.

The author reports on two patients who developed athalamia postoperatively due to external fistulas in the filtering bleb. After initial failure of both conservative and surgical treatment the fistulas were successfully sealed with highly concentrated fibrinogen in combination with thrombin and clotting factor XIII. There was no impairment of the filtering bleb. Principles and techniques of tissue adhesion are described.

Among 128 patients with glaucoma, 19 underwent a revision of a goniotrepanation with scleral flap. Adequate regulation of IOP was achieved in this way, in some cases with additional medication. This revision of the filtering bleb can be recommended as the operation of choice for all forms of glaucoma in which goniotrepanation with scleral flap was performed and in which pressure could not be regulated with additional medication.

The authors tried to establish whether the patient's age has any bearing on the postoperative course of goniotrepanation. A total of 150 eyes operated on, which had been regularly followed up for more than 10 years, were classified in three age groups, each comprising 50 eyes. The following parameters were evaluated: indication for the operation, behavior of the postoperative I.O.P., behaviour of the filtering bleb, behavior of the visual functions, and late complications. The comparative investigations produced the following findings: (1) The postoperative mean IOP value is independent of the patient's age; (2) visual functions were adversely affected to a significant degree postoperatively in older patients, and (3) a cystic configuration of the filtering bleb was significantly more common in older individuals. On the basis of these findings the authors recommend covered sclerectomy procedures, even in younger individuals suffering from chronic simple glaucoma, because the prognosis for the functions and the ultimate fate of the eye is reasonably good.