Cyclodialysis ab interno as a surgical approach to intractable glaucoma

Purpose In glaucoma filtration surgery, the problem of subconjunctival scarring has still not been satisfactorily solved. Suprachoroidal drainage of aqueous humour offers a promising, alternative option for intractable glaucoma. We here present a clinical study on the surgical approach of gonioscopic cyclodialysis ab interno. Patients and methods Twenty-eight eyes of 20 patients with intractable glaucoma were included in this prospective, consecutive, case-control study. The eyes had had a mean of 4.4 ± 2.4 previous antiglaucomatous interventions. Baseline intraocular pressure (IOP) was 34.3 ± 10.5 mmHg despite maximum therapy. Under gonioscopic control, cyclodialysis ab interno was performed over two clock times to gain access to the suprachoroidal space. No additional trabecular meshwork surgery was performed. Success was defined as a lowering of IOP to below 21 mmHg without the need for further medication or intervention. Results Mean postoperative IOP was 14.6 ± 12.4 mmHg. Mean follow-up (FU) for all eyes was 121.8 days. After a mean of 60 days, 21 eyes (75%) needed further surgical intervention. Qualified success was seen in four eyes (14.3%), with a mean FU of 383.6 days. Three eyes (10.7%) showed absolute success after a mean FU period of 202.7 days. In our series, we obtained the best results for phakic eyes, followed by pseudophakic and aphakic eyes. Conclusion The results of this study do not provide convincing evidence of the functional efficacy of cyclodialysis ab interno. Nevertheless, the technique is easy to perform and offers safe and atraumatic access to the resorptive capability of the choroid. Conjunctival manipulation is avoided. Contrary to reports in the current literature, in our series, the best results were obtained for phakic eyes, though the small number of eyes included does not allow reliable statistics. Further studies will need to focus on the use of different space-retaining substances or a widening of the cyclodialysis cleft to improve surgical outcome.     

Procedure guideline for thyroid scintigraphy (version 2)

The version 2 of the procedure guideline for thyroid scintigraphy is an update of the procedure guideline published in 1999. The procedure guideline considers the current amendment of legislative rules (Richtlinie Strahlenschutz in der Medizin 2002). Indication and use of radiopharmaceuticals have to be confirmed by the specialist in nuclear medicine. Activities of 75 MBq technetium-99m, respectively of 10 MBq iodine-123 should not be exceeded without an individual justification. The interpretation of the scintigraphy requires the knowledge of the patients' history, the palpation of the neck, the laboratory parameters, and of the sonography. The interpretation of the technetium-99m uptake requires the knowledge of TSH concentration.     

Multifocal intraocular lens implantation in patients with traumatic cataract

OBJECTIVE: To evaluate the postoperative outcome and complication rate of cataract extraction with implantation of a zonal-progressive multifocal intraocular lens (IOL) for traumatic cataract. DESIGN: Prospective, nonrandomized, comparative trial. PARTICIPANTS: Fifty-one eyes of 51 subjects with traumatic cataract caused by nonpenetrating, penetrating, and perforating ocular trauma at two university institutions with more than 12 months follow-up. INTERVENTIONS: Temporal clear corneal phacoemulsification with foldable IOL implantation was performed in all eyes. In 29 subjects, a zonal-progressive optic multifocal IOL (Array SA40-N Allergan, Irvine, CA) was implanted, whereas 22 subjects received a monofocal IOL and served as controls. RESULTS: Preoperative subjects demographics, mean postoperative spherical equivalent, astigmatism, and uncorrected and best-corrected distance visual acuity were similar in the two groups. Subjects with a multifocal IOL achieved a significantly better uncorrected near visual acuity than subjects with monofocal IOL (0.24 vs. 0.40; P = 0.0001). With distance correction only, mean near visual acuity was 0.21 vs. 0.43 (P = 0.0001). Best-corrected near visual acuity was 0.17 for both groups (P = 0.91), with +1.24 diopters (D) for the multifocal group and +2.45 D for the monofocal group (P = 0.0001). Spectacle dependency differed significantly between the two groups, with 18 (81%) subjects of the monofocal group commonly requiring an additional plus add for near tasks compared with 5 (17%) subjects in the multifocal group (P = 0.001). Stereopsis was superior in the multifocal group (P < 0.001), with 20 (69%) and 16 (55%) patients with a multifocal IOL responding positively to the Lang and Titmus tests, respectively. In the monofocal group, only eight (36%) and five (22%) subjects gave correct answers. CONCLUSIONS: Multifocal IOL implantation is a viable alternative to monofocal pseudophakia in subjects with traumatic cataract.     

UBM-guided chamber angle surgery for glaucoma management: an experimental study

PURPOSE: The aim of this experimental study was to investigate the potential of ultrasound bimicroscopy (UBM)-guided chamber angle surgery as an alternative or supplement to gonioscopy and intraocular microendoscopy for intraoperative control. METHODS: In 15 porcine cadaver eyes, mechanical goniopuncture or punctual Er:YAG laser trabecular ablation was performed without operating microscope or gonioscopy, but with real-life ultrasound biomicroscopy monitoring with a 50 MHz transducer. Intraoperative localization of the microsurgical instruments and tissue-instrument contact were qualitatively evaluated. RESULTS: The instruments could be clearly visualized within the chamber angle and disturbing artefacts were only minimal when using mechanically fixed instruments in slow motion. Topographic localization, tissue contact, and penetration depth of the instruments entering the scleral were well illustrated as far as the technical resolution limits of UBM would allow. CONCLUSIONS: UBM can be used intraoperatively to monitor the correct manoeuvring of microsurgical instruments in selected ab interno procedures. Some adaptations and further modifications of the technique presented here will be necessary before UBM-guided surgery can be considered for clinical use in humans.     

A novel approach to suprachoroidal drainage for the surgical treatment of intractable glaucoma

PURPOSE: In glaucoma surgery, scarring of the artificial fistula is the limiting factor for long-term control of intraocular pressure (IOP). Several devices and surgical techniques have been developed for artificial aqueous humor drainage in intractable glaucoma. The authors describe a novel surgical technique that uses a silicone tube as a shunt for aqueous flow from the anterior chamber to the suprachoroidal space. PATIENTS AND METHODS: Thirty-one eyes of 31 patients with uncontrollable refractory glaucoma were included in this prospective consecutive case-control study. Each eye had undergone an average of 3.5+/-1.9 previous interventions for glaucoma. The baseline IOP was 44.25+/-8.7 mm Hg despite maximum therapy. As in trabeculectomy, a limbus-based scleral flap was prepared. The suprachoroidal space was accessed via a deep posterior scleral flap. The silicone tube was inserted as an intrascleral connection from the anterior chamber to the suprachoroidal space. Cyclodialysis was avoided by this surgical approach. Success was defined as a lowering of IOP to below 21 mm Hg without the need for further medication or intervention. RESULTS: The mean functional shunt survival was 55.9+/-45.6 weeks. IOP was reduced to 12.9+/-5.2 mm Hg in 70% of all eyes after 30 weeks postoperatively. After 52 weeks, 60% of the eyes could be classified as representing success, and 76 weeks after surgery, 40% of the eyes still showed controlled IOP. In none of the eyes were severe postoperative hypotony or suprachoroidal bleeding observed. No localized or general inflammation or infection was seen in connection with the silicon tube. Two patients needed anterior chamber lavage because of bleeding. In 2 patients the tube had to be removed because of corneal endothelial contact. Shunt failure of the tube was caused in some cases by connective tissue formation at the posterior lumen of the tube. CONCLUSION: This novel surgical approach and the placement of the silicone tube described here have several advantages. Its intrascleral course minimizes the risk of conjunctival erosion and associated infections. No cyclodialysis is performed. Connection to the suprachoroidal space exploits the resorptive capability of the choroid. It guarantees drainage but also provides a natural counterpressure, avoiding severe postoperative hypotony. The suprachoroidal shunt presented here achieves good follow-up results in terms of IOP control. No serious complications have been observed. This new method promises to be an effective surgical technique and presents a new therapeutic option in intractable glaucoma. Fibroblast reaction obstructing the posterior lumen, seemed to be the only factor limiting drainage. Further studies and experiments will be needed to elucidate the exact physiologic mechanisms underlying the draining, the capacity and duration of the draining effect, and the histologic background of suprachoroidal scarring.     

Adjunctive mitomycin C in primary trabeculectomy in young adults: a long-term study of case-matched young patients

· Objective: The purpose of this study was to determine the efficacy of initial mitomycin C (MMC)-augmented trabeculectomy for uncomplicated glaucoma in young patients. · Methods: A retrospective chart review was performed on all glaucoma patients aged between 15 and 40 years without previous surgery that underwent initial trabeculectomy with MMC between 1988 and 1995 at the University Eye Hospital of Cologne. Success (survival) was defined as an intraocular pressure (IOP) of 21 mmHg or lower, with (qualified success) or without (complete success) glaucoma medications. The results were compared with a case-matched control group that did not receive antiproliferative therapy. · Results: Eleven eyes of 11 patients fulfilled the inclusion criteria of initial MMC-augmented trabeculectomy. Using cumulative life-table analysis the success rate was 91% at 1 year and 73% at 5 years for the control group. For the MMC group the success rate was 91% at 1 year and 5 years, respectively. At final visit, mean IOP was significantly (P<0.001) lower for the MMC group (13.3±3.9 mmHg) than for controls (18.0±1.3 mmHg). Significant differences were also found in the complication rate: complications associated with excessive aqueous overfiltration, such as shallow anterior chamber (36%), choroidal detachment (45%) and persistent hypotony (27%), featured particularly in the MMC group. Conversely, scarring of the filtering bleb (18%) and Tenon’s cysts (18%) were observed exclusively in control eyes. · Conclusion: The present results suggest that initial MMC trabeculectomy for uncomplicated glaucoma in young patients significantly reduces IOP and number of adjunctive medications, postoperatively, albeit at the price of a high incidence of hypotony. Received: 24 November 1997 Revised version received: 19 January 1998 Accepted: 27 January 1998     

Multifocal intraocular lens implantation in pediatric cataract surgery

OBJECTIVE: To evaluate implantation of a zonal-progressive multifocal intraocular lens (IOL) in children. STUDY DESIGN: Prospective, noncomparative, interventional case series. PARTICIPANTS: Thirty-five eyes of 26 pediatric patients aged 2 to 14 years with multifocal IOL implantation at one institution with more than 1 year of follow-up. INTERVENTIONS: Standard surgical procedure comprised an anterior capsulorrhexis, lens material aspiration via two side-port incisions, temporal tunnel incision, and multifocal IOL (SA40-N; Allergan, Irvine, CA) implantation in all eyes. In 24 eyes (68%), a 5-mm posterior capsulorrhexis was created with forceps, followed by an anterior vitrectomy in 19 of those eyes (54%). RESULTS: Twenty-six patients (35 eyes) had an average follow-up of 27.4 +/- 12.7 months (range, 12-58 months). At last follow-up, best-corrected distance visual acuity improved significantly (P = 0.001), 71% of eyes with a visual acuity of 20/40 or better and 31% of eyes with a visual acuity of 20/25 or better. In the 9 bilateral cases, spectacle dependency was moderate, with only 2 children (22%) reporting the permanent use of an additional near correction. The remaining children were either using distance-correction only (4 patients; 44%) or no glasses at all (3 patients; 33%). Stereopsis also improved significantly after multifocal IOL implantation (P = 0.01). Sixteen eyes (46%) experienced obscuration of the entrance pupil that required intervention, with 10 requiring a second intraocular surgery. Four eyes required an anterior membranectomy for persistent fibrinous membrane. Intraocular lens decentration requiring surgical intervention developed in six eyes. CONCLUSIONS: Multifocal IOL implantation is a viable alternative to monofocal pseudophakia in this age group.