Functional and anatomical outcomes of vitreoretinal surgery for posterior segment complications after elective cataract surgery

PURPOSE: To assess the outcomes in patients who required 1 or more vitreoretinal interventions for posterior segment complications arising from elective uneventful cataract surgery. SETTING: Tertiary referral center, single-center study. METHODS: A retrospective interventional case series included 56 consecutive patients who were referred for surgical correction of posterior segment complications within 6 months of cataract surgery. The study period was between 1996 and 2003, and the minimum follow-up was 5 months. RESULTS: Posterior segment complications were resolved with a single surgical intervention in 40 cases (71.4%). Within 5 months of primary surgical correction, persisting or newly arising posterior segment complications were noted in 16 cases (28.6%). After a mean of 2.1 +/- 1.4 (SD) additional surgeries, the number of eyes with posterior segment problems decreased to 7 (12.5%) (P = .035). Posterior segment complications requiring more than 1 vitreoretinal intervention included retinal detachment, endophthalmitis, and choroidal hemorrhages. After primary correction surgery, the mean best corrected visual acuity increased from 0.15 +/- 0.24 to 0.37 +/- 0.33 (P = .001) after a single intervention and to 0.39 +/- 0.32 (P>.05) after additional interventions. Although the intraocular pressure (IOP) decreased from 21.8 +/- 16.6 mm Hg to 14.9 +/- 3.4 mm Hg (P = .008), 4 (7.1%) consecutive vascular optic atrophies occurred. A reduction in corneal transparency was observed in 46.4% of patients before primary surgical correction and 12.5% after primary surgical correction (P<.001). CONCLUSIONS: In many cases, posterior segment complications arising from cataract surgery could be repaired with favorable functional and anatomical outcomes by a single vitreoretinal intervention. Additional surgery, if requested, provided stabilization of the anatomical and functional outcomes.

[Safety of treatment with tacrolimus ointment for anterior segment inflammatory diseases]

BACKGROUND: The off-label use of topical tacrolimus (Protopic) for inflammatory external eye diseases is gaining popularity. However, there are no reports on the safety profile of this new treatment option. PATIENTS AND METHODS: We treated six patients with different inflammatory eye diseases with topical tacrolimus (Protopic 0.03 %) as off-label use in addition to the conventional anti-inflammatory treatment. Patients were interviewed for side effects and serum drug concentrations were measured under steady state conditions one hour after topical application of tacrolimus ointment. RESULTS: Two patients reported a slight burning sensation immediately after application, in one patient we found a slight worsening of the dry eye problems. No patient abandoned the treatment due to side effects. Serum drug concentrations remained below the analytical threshold in all cases (< 1.5 ng/ml). CONCLUSIONS: Tacrolimus for the topical treatment of anterior segment inflammatory eye diseases is well tolerated without detectable systemic drug resorption.

Biomechanics of the Spine

The human spinal column is a complex structure composed of 24 individual vertebrae plus the sacrum. The principal functions of the spine are to protect the spinal cord, to provide mobility to the trunk and to transfer loads from the head and trunk to the pelvis. By nature of a natural sagittal curvature and the relatively flexible intervertebral discs interposed between semi-rigid vertebrae, the spinal column is a compliant structure which can filter out shock and vibrations before they reach the brain. The intrinsic, passive stability of the spine is provided by the discs and surrounding ligamentous structures, and supplemented by the actions of the spinal muscles. The seven intervertebral ligaments which span each pair of adjacent vertebrae and the two synovial joints on each vertebra (facets or zygapophyseal joints) allow controlled, fully three-dimensional motion.

Differences in endplate deformation of the adjacent and augmented vertebra following cement augmentation

Vertebral cement augmentation can restore the stiffness and strength of a fractured vertebra and relieve chronic pain. Previous finite element analysis, biomechanical tests and clinical studies have indirectly associated new adjacent vertebral fractures following augmentation to altered loading. The aim of this repeated measures in situ biomechanical study was to determine the changes in the adjacent and augmented endplate deformation following cement augmentation of human cadaveric functional spine units (FSU) using micro-computed tomography (micro-CT). The surrounding soft tissue and posterior elements of 22 cadaveric human FSU were removed. FSU were assigned to two groups, control (n = 8) (loaded on day 1 and day 2) and augmented (n = 14) (loaded on day 1, augmented 20% cement fill, and loaded on day 2). The augmented group was further subdivided into a prophylactic augmentation group (n = 9), and vertebrae which spontaneously fractured during loading on day 1 (n = 5). The FSU were axially loaded (200, 1,000, 1,500-2,000 N) within a custom made radiolucent, saline filled loading device. At each loading step, FSUs were scanned using the micro-CT. Endplate heights were determined using custom software. No significant increase in endplate deformation following cement augmentation was noted for the adjacent endplate (P > 0.05). The deformation of the augmented endplate was significantly reduced following cement augmentation for both the prophylactic and fracture group (P < 0.05, P < 0.01, respectively). Endplate deformation of the controls showed no statistically significant differences between loading on day 1 and day 2. A linear relationship was noted between the applied compressive load and endplate deflection (R (2) = 0.58). Evidence of significant endplate deformation differences between unaugmented and augmented FSU, while evident for the augmented endplate, was not present for the adjacent endplate. This non-invasive micro-CT method may also be useful to investigate endplate failure, and parameters that predict vertebral failure.

How to Tango: a manual for implementing Spine Tango

The generic approach of the Spine Tango documentation system, which uses web-based technologies, is a necessity for reaching a maximum number of participants. This, in turn, reduces the potential for customising the Tango according to the individual needs of each user. However, a number of possibilities still exist for tailoring the data collection processes to the user's own hospital workflow. One can choose between a purely paper-based set-up (with in-house scanning, data punching or mailing of forms to the data centre at the University of Bern) and completely paper-free online data entry. Many users work in a hybrid mode with online entry of surgical data and paper-based recording of the patients' perspectives using the Core Outcome Measures Index (COMI) questionnaires. Preoperatively, patients can complete their questionnaires in the outpatient clinic at the time of taking the decision about surgery or simply at the time of hospitalisation. Postoperative administration of patient data can involve questionnaire completion in the outpatient clinic, the handing over the forms at the time of discharge for their mailing back to the hospital later, sending out of questionnaires by post with a stamped addressed envelope for their return or, in exceptional circumstances, conducting telephone interviews. Eurospine encourages documentation of patient-based information before the hospitalisation period and surgeon-based information both before and during hospitalisation; both patient and surgeon data should be acquired for at least one follow-up, at a minimum of three to six months after surgery. In addition, all complications that occur after discharge, and their consequences should be recorded.

Benchmarking with Spine Tango: potentials and pitfalls

The newly released online statistics function of Spine Tango allows comparison of own data against the aggregated results of the data pool that all other participants generate. This comparison can be considered a very simple way of benchmarking, which means that the quality of what one organization does is compared with other similar organizations. The goal is to make changes towards better practice if benchmarking shows inferior results compared with the pool. There are, however, pitfalls in this simplified way of comparing data that can result in confounding. This means that important influential factors can make results appear better or worse than they are in reality and these factors can only be identified and neutralized in a multiple regression analysis performed by a statistical expert. Comparing input variables, confounding is less of a problem than comparing outcome variables. Therefore, the potentials and limitations of automated online comparisons need to be considered when interpreting the results of the benchmarking procedure.