Practicability for robot-aided measurement of knee stability in-vivo.

BACKGROUND: For the analysis of different treatments concerning anterior cruciate ligament (ACL) rupture, objective methods for the quantification of knee stability are needed. Therefore, a new method for in-vivo stability measurement using a robotic testing system should be developed and evaluated. METHODS: A new experimental setting was developed using a KUKA robot and a custom-made chair for the positioning and fixation of the participants. The tibia was connected to the robot via a Vacoped shoe and magnetic buttons, providing adequate safety. Anterior tibial translation and internal tibial rotation were measured on both legs of 40 healthy human subjects at 30°, 60° and 90° of flexion, applying anterior forces of 80 N and internal torques of 4 Nm, respectively. RESULTS: While the mean differences between the right and left leg measured for anterior tibial translation were within an acceptable range (<1.5 mm), the absolute values were substantially large (38-40.5 mm). For mean internal tibial rotation, between 17.5 and 20° were measured at the different sides and flexion angles, with a maximal difference of 0.75°. High reproducibility of the measurements could be demonstrated for both, anterior tibial translation (ICC(3,1) = 0.97) and internal tibial rotation (ICC(3,1) = 0.94). CONCLUSIONS: Excellent results were achieved for internal tibial rotation, almost reproducing current in-vitro studies, but too large anterior tibial translation was measured due to soft-tissue compression. Therefore, high potential for the analysis of ACL related treatments concerning rotational stability is seen for the proposed method, but further optimization is necessary to enhance this method for the reliable measurement of anterior tibial translation.

Purtscher's retinopathy after intramedullary nailing of a femoral shaft fracture in a 20-year old healthy female - report of a rare case and review of the literature.

BACKGROUND: Purtscher's retinopathy is a sight threatening, occlusive microvasculopathy associated with trauma, it is rarely reported after long bone fractures. CASE PRESENTATION: A 20-year-old female sustained a femoral shaft fracture (AO 32-A2.3) in a ski accident colliding with a snowgun and was treated with intramedullary nailing one hour after the accident. 14 hours after surgery the patient complained of loss of vision in both eyes and was therefore referred to a neurologist, furthermore an MRI scan of the brain was performed. Neither showed any pathological findings. The patient was finally transferred to an ophthalmology department. After slit lamp examination and funduscopy Purtscher's retinopathy was diagnosed. Treatment was started right after diagnosis and 5 days after the onset of symptoms. The patient was administered intravenous haemo-rheologic therapy for five days as well as low molecular heparine in therapeutic dose and Vasonit® 400 mg bid orally.At follow-up 4 weeks and 6 months later visual acuity had improved after 4 weeks before that exam. At final follow-up the symptoms had almost resolved completely and uncorrected visual acuity (UCVA) and best corrected visual acuity had improved from originally 0.25 decimal in both eyes to 0.8 decimal UCVA and BCVA in both eyes. CONCLUSIONS: Patients suffering from perioperative loss of vision have to be referred for ophthalmological and neurological assessment as soon as possible. History of trauma and visual loss can point to the diagnosis of Purtscher's retinopathy.

Comparison of short-term refractive surgery outcomes after wavefront-guided versus non-wavefront-guided LASIK.

PURPOSE: To evaluate and compare visual and refractive outcomes after laser-assisted in situ keratomileusis (LASIK) surgery for the correction of myopia or myopic astigmatism using 3 different treatment protocols. METHODS: We included 736 eyes of 369 patients (age 18-62 years) divided into 3 groups: 235 eyes of 118 patients (MEL80 group) undergoing LASIK using optimized aspheric ablation profiles (MEL80 excimer laser; Carl Zeiss Meditec), 248 eyes of 124 patients (Wavescan group) undergoing wavefront-guided (WFG) LASIK (STAR S4IR excimer laser + Wavescan aberrometer; Abbott Medical Optics), and 253 eyes of 127 patients (iDesign group) undergoing WFG LASIK (STAR S4IR excimer laser + iDesign system; Abbott Medical Optics). Visual and refractive outcomes were evaluated 2 months after surgery. RESULTS: A total of 91% (215/235), 95% (237/248), and 99% (251/253) of eyes achieved a postoperative uncorrected distance visual acuity of 0.0 logMAR (≈20/20) in the MEL80, Wavescan, and iDesign groups, respectively. Postoperative spherical equivalent (SE) was within ±0.5 D in 95% (223/235), 98% (242/248), and 100% (253/253) of eyes in these same 3 groups, respectively. Likewise, manifest cylinder was below 0.50 D in 95% (223/235), 97% (241/248), and 100% (253/253) of eyes. Significant differences in postoperative SE and cylinder were found between the MEL80 and iDesign groups (p<0.05). CONCLUSIONS: All evaluated LASIK treatment protocols are predictable and effective for the correction of myopia. The treatment planned with a high resolution aberrometer obtained the best postoperative refractive outcomes.

Randomized controlled clinical trial to evaluate different intraocular lenses for the surgical compensation of low to moderate-to-high regular corneal astigmatism during cataract surgery.

PURPOSE: To evaluate vector analysis, rotational stability, and visual outcomes after implantation of toric IOLs with low (<2.25 diopter [D]) toric values (Acrysof IQ SN6AT3 or SN6AT4) and moderate-to-high toric (3.00 D to 6.00 D) values (Acrysof IQ SN6AT5, SN6AT6, SN6AT7, SN6AT8, or SN6AT9) versus after implantation of a nontoric IOL (Acrysof SN60WF) in eyes with regular topographic corneal astigmatism. SETTING: Department of Ophthalmology, Paracelsus Medical University Salzburg, Salzburg, Austria. DESIGN: Randomized controlled clinical trial. METHODS: The study included eyes of patients undergoing phacoemulsification and IOL implantation. Patients were randomized into 3 groups to bilaterally receive the nontoric IOL, the low toric IOL, or the moderate-to-high toric IOL. Over a 6-week follow-up period, rotational stability and astigmatic changes were evaluated in the 2 toric IOL groups using the Alpins vector method. RESULTS: The study included 78 eyes of 39 patients. Postoperatively mean refractive astigmatism decreased significantly from 1.45 D ± 1.18 (SD) to 0.36 ± 0.44 D in the low toric group and from 1.92 ± 1.09 D to 0.31 ± 0.46 D in the moderate-to-high toric group. There was no significant difference between mean difference vectors in the low toric IOL group and the moderate-to-high toric IOL group. A significant difference in the correction index was detected, revealing overcorrection with low toric IOLs (1.03 ± 0.12 D) and undercorrection with moderate-to-high toric IOLs (0.95 ± 0.12 D). CONCLUSIONS: Implantation of low toric IOLs and medium-to-high toric IOLs in patients with low to moderate-to-high corneal astigmatism was shown to be effective in correcting regular corneal astigmatism. Undercorrection in the moderate-to-high group could be related to misalignment. FINANCIAL DISCLOSURE: This research project was financially supported by the Fuchs Foundation for the Promotion of Research in Ophthalmology, Salzburg, Austria. Alcon Inc. financially supports the Fuchs-Foundation as the clinical research center of the Department of Ophthalmology of the Paracelsus Medical University Salzburg, Salzburg, Austria (Grant Number 2010-37). No author has a financial or proprietary interest in any material or method mentioned.

A classification-system improves the intra- and interobserver reliability of radiographic diagnosis of "pistol-grip-deformity".

Early detection of pistol-grip-deformity may be beneficial in optimising the outcome and the cost effectiveness of surgery. It is important to identify reliable radiographic parameters in assessing femoro-acetabular impingement (FAI) to develop a treatment algorithm. Radiographs of 47 patients ranging from "pistol grip deformity" to a normal head-neck-junction were measured for alpha angle and head ratio, and then classified by two different observers. The Bland-Altman plot was used for inter- and intraobserver agreement of alpha angle and head ratio. Inter- and intraobserver agreement for classification of "pistol grip deformity" was determined using weighted Cohen's kappa coefficient. Observer I achieved a kappa coefficient of 0.97. Observer II achieved a kappa coefficient of 0.92. An interobserver kappa coefficient between 0.87 and 0.92 was achieved by using a classification system. By testing for interobserver agreement, a bias of -0.004 with an upper limit of 0.461 and a lower limit of -0.47 was seen for the ratio and a bias of -3.7 with an upper limit of 17.2 and a lower limit of -24.6 for the alpha angle. Therefore, poor results were seen for intra- and interobserver reliability by using only a single plane for classification of "pistol grip deformity". The strength of agreement could be improved by using a classification system (based on two planes).

Polymorphisms in the genes encoding chemokine receptor 5, interleukin-10, and monocyte chemoattractant protein 1 contribute to cytomegalovirus reactivation and disease after allogeneic stem cell transplantation.

We analyzed 90 polymorphisms in 17 genes related to immune function for association with human cytomegalovirus (HCMV) reactivation and disease in patients after allogeneic stem cell transplantation. We found relevant markers (i) in CCR5 and IL-10 genes conferring a higher risk for the development of HCMV disease and (ii) in the MCP1 gene associated with HCMV reactivation. Testing of high-risk patients for the presence of these single-nucleotide polymorphisms might be useful for individualizing antiviral prophylaxis.