Coaxial Group Research Articles

Coaxial nanofibers encapsulated with Ampelopsis brevipedunculata extract and green synthesized AgNPs for wound repair

Silver nanoparticles (AgNPs) synthesized from Aloe vera extract exhibited a pronounced antibacterial effect, while the Ampelopsis brevipedunculata extract (ABE) showcased a high antioxidant capacity for wound healing. Spherical AgNPs with a particle size of 28.82 nm crystallized in a face-centered-cubic lattice. AgNPs/polyvinyl alcohol (PVA) and ABE/polycaprolactone (PCL) underwent electrospinning to produce coaxial and electrosprayed nanofibers, respectively. The developed coaxial nanofibers demonstrated a strain of 159%, a Young’s modulus of elasticity of 7080.14 kPa, a 3.9-fold swelling ratio, a water contact angle of 38.91°, characteristic hydrophilicity, and an adequate water vapor transmission rate of 2272 g/m2/day. ABE exhibited no cytotoxicity to L929 cells and induced a twofold increase in the cell migration rate. Upon applying the developed coaxial nanofiber on an in vivo rat model with a 9 mm wound diameter, the wound rapidly and completely healed within 10 days, with a healing speed 60% greater than that of the control group. Histopathological analysis revealed that the coaxial group did not exhibit inflammation, showed complete epithelization, and featured a well-arranged deposition of collagen on the 10th day.

Percutaneous ultrasound-guided renal biopsies in a paediatric population: comparison of coaxial and non-coaxial techniques using 18-gauge core biopsy needles.

Percutaneous ultrasound-guided biopsy is performed in paediatric patients for evaluation of diffuse renal parenchymal disease. When compared with the non-coaxial technique, the coaxial technique has the advantages of obtaining multiple tissue cores via a single capsular puncture and post-biopsy tract embolisation. To compare the coaxial and non-coaxial techniques of percutaneous ultrasound (US)-guided biopsy of native kidney parenchyma in children and adolescents with renal disease. We retrospectively identified consecutive patients who underwent percutaneous US-guided renal biopsy using an 18-gauge core biopsy needle from July 2019 to July 2021 in a single tertiary paediatric nephrology centre. Focal renal tumour biopsy and transplant kidney biopsy were excluded. The total glomerular yield, specimen adequacy, complication rate and procedural time between the coaxial and non-coaxial groups were compared. There were 34 percutaneous US-guided renal biopsies: 22 using a coaxial technique and 12 using a non-coaxial technique. The total median glomerular yield obtained was higher in the coaxial group (coaxial=37.9; non-coaxial=22.2; P=0.02). No statistically significant difference was noted between specimen adequacy (coaxial=100%; non-coaxial=91.7%; P=0.35). While no statistically significant difference was detected for overall complication rates (coaxial=13.6%; non-coaxial=41.7%; P=0.09), the coaxial group had a lower rate of haemorrhagic complications (coaxial=4.5%; non-coaxial=41.7%; P=0.01). One patient in the non-coaxial group had post-biopsy haemorrhage requiring embolisation. The procedural time was shorter in the coaxial group (coaxial=26.3 ± 7.0min; non-coaxial=51.3 ± 11.5min; P<0.001). Percutaneous US-guided renal biopsy in children using the coaxial technique has significantly higher total glomerular yield, shorter procedural time and fewer haemorrhagic complications, compared to biopsies using the non-coaxial technique.

Long-term clinical outcomes obtained with bilateral implantation of a multifocal intraocular lens through two different-sized corneal incisions

PURPOSE:To evaluate the long-term visual function and patient satisfaction in patients implanted bilaterally with the same type of multifocal intraocular lens (MIOL), using either a 2.2 mm small corneal incision with bimanual irrigation/aspiration (I/A) or a conventional 2.75 mm incision with coaxial I/A.METHODS:Prospective nonrandomized study including 100 eyes of 50 patients who underwent bilateral implantation of ReSTOR SN6AD1 through a 2.2 mm or 2.75 mm corneal incision. Outcomes included visual function measures (near, intermediate, and distance visual acuity [VA]), achievement of targeted refraction and postoperative astigmatism. Patient satisfaction was evaluated using a subjective questionnaire.RESULTS:Three and 12 months postoperatively, distance uncorrected best VA (UBVA) was 0.98 ± 0.07, UBVA at 30 cm was J1 in 100% of cases and UBVA at 60 cm was J3 in 72% of cases. Targeted refraction was achieved in 84% of cases and postoperative astigmatism was −0.4 ± 0.3 diopters. There was no statistically significant difference in UBVA in all distances, targeted refraction and postoperative astigmatism between the small-incision bimanual and the conventional coaxial group. Sixty percent of the patients were satisfied, 30% were very satisfied and 10% declared that the result did not meet their expectations. Three out of 5 nonsatisfied patients had an angle kappa of 4° and the MIOL was not well-centered.CONCLUSION:An incision size of 2.2 mm compared to 2.75 mm, did not appear to result in less surgically induced astigmatism after the implantation of a MIOL. SN6AD1 is a reliable MIOL choice for spectacle independence. Good preoperative patient selection is of crucial importance for the outcome in MIOLs.

Coaxial bioelectrospinning of P34HB/PVA microfibers biomimetic scaffolds with simultaneity cell-laden for improving bone regeneration

Poorly functioning scaffold materials and limitations in material-cell construction technology remain problems in bone tissue engineering. Electrospinning has been proven to be a suitable and available technique for production of 3D biomimetic scaffolds. To overcome these problems and retain the advantages of electrospinning, bioelectrospinning has been proposed to provide guidance by micropattern, homogeneous cell distribution, and effective nutrient utilization. Herein, we fabricated poly (3-hydroxybutyrate-co-4-hydroxybutyrate)/poly (vinyl alcohol) (P34HB/PVA) with human bone mesenchymal stem cells (hBMSCs) to biomimetic core-shell microfiber/cells complex by coaxial bioelectrospinning. Characterization of the fiber materials revealed that coaxial electrospinning combined the advantages of the two materials. In vitro cellular assays showed that after bioelectrospinning, the cells and material could be simultaneously spun while maintaining cell activity. The material provided a good 3D microenvironment allowing cell adhesion, proliferation, and differentiation. Both the in vitro and in vivo tests indicated the formation of mineralized nodules in both the co-spun and co-axial groups, while the implants formed bone-like tissue after 16 weeks of implantation. This study shows that coaxial bioelectrospinning technology can be used to construct tissue-engineered bone. Our technique might be applied in the future to fabricate more complex tissue and organs.

Design and characterization of small-diameter tissue-engineered blood vessels constructed by electrospun polyurethane-core and gelatin-shell coaxial fiber

ABSTRACT Substitution or bypass is the most effective treatment for vascular occlusive diseases. The demand for artificial blood vessels has seen an unprecedented rise due to the limited supply of autologous blood vessels. Tissue engineering is the best approach to provide artificial blood vessels. In this study, a new type of small-diameter artificial blood vessel with good mechanical and biological properties was designed by using electrospinning coaxial fibers. Four groups of coaxial fibers vascular membranes having polyurethane/gelatin core-shell structure were cross-linked by the EDC-NHS system and characterized. The core-shell structure of the coaxial vascular fibers was observed by transmission electron microscope. After the crosslinking, the stress and elastic modulus increased and the elongation decreased, burst pressure of 0.11 group reached the maximum (2844.55 ± 272.65 mmHg) after cross-linking, which acted as the experimental group. Masson staining identified blue-stained ring or elliptical gelatin ingredients in the vascular wall. The cell number in the vascular wall of the coaxial group was found in muscle embedding experiment significantly higher than that of the non-coaxial group at all time points(p < 0.001). Our results showed that the coaxial vascular graft with the ratio of 0.2:0.11 had better mechanical properties (burst pressure reached 2844.55 ± 272.65 mmHg); Meanwhile its biological properties were also outstanding, which was beneficial to cell entry and offered good vascular remodeling performance. Polyurethane (PU); Gelatin (Gel); Polycaprolactone (PCL); polylactic acid (PLA);1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC); N-Hydroxy succinimide (NHS); 4-Morpholine-ethane-sulfonic (MES); phosphate buffered saline (PBS); fetal calf serum (FCS); Minimum Essential Medium (MEM); Dimethyl sulfoxide (DMSO); hematoxylin-eosin (HE).

Outcome of cataract extraction with IOL implantation after coaxial and bimanual phacoemulsification

Purpose: To compare the outcome of cataract extraction with IOL implantation after coaxial and bimanual phacoemulsification. Materials and Methods: A prospective study was done to compare the outcome of cataract extraction with IOL implantation after coaxial and bimanual phacoemulsification. The study included 200 patients visiting ophthalmology OPD of Punjab Institute of Medical Sciences who were diagnosed as having cataract and were fit to undergo surgery. Of these 100 patients were randomly assigned to each group. Data analysis included demographics and evaluation of visual acuity (VA) outcome, surgically induced astigmatism, mean phacoemulsification time, effective phacoemulsification time and amount of BSS used. Results: Age and sex distribution was similar in two groups. The mean BCVA in the coaxial and bimanual groups was 0.294 and 0.2903 respectively. The magnitude of surgically induced astigmatism had a mean of 0.845 in the coaxial group and a mean of 0.855 in the bimanual group; hence the difference was not statistically significant. Statistically significant differences were found in mean phacoemulsification time (p = 0.01) which was significantly lower in bimanual phacoemulsification group than the coaxial group. Effective phacoemulsification time (p = 0.022) was significantly lower in bimanual phacoemulsification group (mean = 6.86) than the coaxial group (mean = 12.87). The total surgical time was lower in the bimanual group (mean = 21.94) than the coaxial group (mean= 24.29) and the difference was statistically significant. Conclusion: Both techniques were considered safe and equally effective with regard to cataract surgery with minor differences which did not affect the final outcome and resulted in early post-operative visual rehabilitation with minimal post-operative morbidity, thus leading to increased patient comfort. Keywords: Bimanual, Cataract, Coaxial, Microincision, Phacoemulsification, Surgical time.

Pneumothorax Complicating Coaxial and Non-coaxial CT-Guided Lung Biopsy: Comparative Analysis of Determining Risk Factors and Management of Pneumothorax in a Retrospective Review of 650 Patients.

To assess the scope and determining risk factors related to the development of pneumothorax throughout CT-guided biopsy of pulmonary lesions in coaxial and non-coaxial techniques and the outcome of its management. The study included CT-guided percutaneous lung biopsies in 650 consecutive patients (407 males, 243 females; mean age 54.6years, SD 5.2) from November 2008 to June 2013 in a retrospective design. Patients were classified according to lung biopsy technique into coaxial group (318 lesions) and non-coaxial group (332 lesions). Exclusion criteria for biopsy were lesions <5mm in diameter, uncorrectable coagulopathy, positive-pressure ventilation, severe respiratory compromise, pulmonary arterial hypertension, or refusal of the procedure. Risk factors related to the occurrence of pneumothorax were classified into: (a) Technical risk factors, (b) patient-related risk factors, and (c) lesion-associated risk factors. Radiological assessments were performed by two radiologists in consensus. Mann-Whitney U test and Fisher's exact tests were used for statistical analysis. p values <0.05 were considered statistically significant. The incidence of pneumothorax complicating CT-guided lung biopsy was less in the non-coaxial group (23.2%, 77 out of 332) than the coaxial group (27%, 86 out of 318). However, the difference in incidence between both groups was statistically insignificant (p=0.14). Significant risk factors for the development of pneumothorax in both groups were emphysema (p<0.001 in both groups), traversing a fissure with the biopsy needle (p value 0.005 in non-coaxial group and 0.001 in coaxial group), small lesion, less than 2cm in diameter (p value of 0.02 in both groups), location of the lesion in the basal or mid sections of the lung (p=0.003 and <0.001 in non-coaxial and coaxial groups, respectively), and increased needle track path within the lung tissue of more than 2.5cm (p=0.01 in both groups). The incidence of pneumothorax in the non-coaxial group was significantly correlated to the number of specimens obtained (p=0.006). This factor was statistically insignificant in the coaxial group (p=0.45). The biopsy yield was more diagnostic and conclusive in the coaxial group in comparison to the non-coaxial group (p=0.008). Simultaneous incidence of pneumothorax and pulmonary hemorrhage was 27.3% (21/77) in non-coaxial group and in 30.2% (26/86) in coaxial group. Conservative management was sufficient for treatment of 91 out of 101 patients of pneumothorax in both groups (90.1%). Manual evacuation of pneumothorax was efficient in 44/51 patients (86.3%) in both groups and intercostal chest tube was applied after failure of manual evacuation (7 patients: 13.7%), from which one patient developed a persistent air leakage necessitating pleurodesis. Pneumothorax complicating CT-guided core biopsy of pulmonary lesions, showed the insignificant difference between coaxial and non-coaxial techniques. However, both techniques have the same significant risk factors including small and basal lesions, increased lesion's depth from pleural surface, and increased length of aerated lung parenchyma crossed by biopsy needle and passing through pulmonary fissures in the needle tract.

Bimanual microincision versus coaxial phacoemulsification cataract surgery

Background Bimanual microincision and coaxial phacoemulsification are the modalities of cataract surgery. Objectives The aim of the study was to evaluate bimanual microincision phacoemulsification versus coaxial phacoemulsification cataract surgery. Patients and methods Thirty patients were enrolled between December 2011 and March 2013, all with symptoms related to cataract. Fifteen patients were randomly assigned to the bimanual microincision group and another 15 patients to the coaxial phacoemulsification group. All patients were followed after 1 day, 1 week, 1 month, and 3 months of the procedure. The primary outcome of our study was lowering of astigmatism in the bimanual microincision procedure. Results The bimanual group demonstrated a reduced surgically induced astigmatism (SIA). The coaxial group demonstrated a slight rise in SIA. There is a highly significant difference between postoperative SIA in both groups during the postoperative period ( P Conclusion Microincisional cataract surgery using bimanual phacoemulsification has many advantages but it is limited by the lack of suitable intraocular lenses for implantation through microincisions; hence, switching to this technique from the conventional one still depends on the surgeon's performance.

Risk factor analysis of pulmonary hemorrhage complicating CT-guided lung biopsy in coaxial and non-coaxial core biopsy techniques in 650 patients

PurposeTo evaluate the risk factors involved in the development of pulmonary hemorrhage complicating CT-guided biopsy of pulmonary lesions in coaxial and non-coaxial techniques. Materials and methodsRetrospective study included CT-guided percutaneous lung biopsies in 650 consecutive patients (407 males, 243 females; mean age 54.6 years, SD: 5.2) from November 2008 to June 2013. Patients were classified according to lung biopsy technique in coaxial group (318 lesions) and non-coaxial group (332 lesions). Exclusion criteria for biopsy were: lesions <5mm in diameter, uncorrectable coagulopathy, positive-pressure ventilation, severe respiratory compromise, pulmonary arterial hypertension or refusal of the procedure. Risk factors for pulmonary hemorrhage complicating lung biopsy were classified into: (a) patient's related risk factors, (b) lesion's related risk factors and (d) technical risk factors. Radiological assessments were performed by two radiologists in consensus. Mann–Whitney U test and Fisher's exact tests for statistical analysis. p values <0.05 were considered statistically significant. ResultsIncidence of pulmonary hemorrhage was 19.6% (65/332) in non-coaxial group and 22.3% (71/318) in coaxial group. The difference in incidence between both groups was statistically insignificant (p=0.27). Hemoptysis developed in 5.4% (18/332) and in 6.3% (20/318) in the non-coaxial and coaxial groups respectively. Traversing pulmonary vessels in the needle biopsy track was a significant risk factor of the development pulmonary hemorrhage (incidence: 55.4% (36/65, p=0.0003) in the non-coaxial group and 57.7% (41/71, p=0.0013) in coaxial group). Other significant risk factors included: lesions of less than 2cm (p value of 0.01 and 0.02 in non-coaxial and coaxial groups respectively), basal and middle zonal lesions in comparison to upper zonal lung lesions (p=0.002 and 0.03 in non-coaxial and coaxial groups respectively), increased lesion's depth from the pleural surface (p=0.021 and 0.018 in non-coaxial and coaxial groups respectively), increased distance of traversed lung in the needle track of more than 2.5cm (p=0.001 in both groups). Insignificant risk factors were patient's age, gender or emphysema in both groups (p value >0.1 in both groups). Concomitant incidence of pneumothorax was 32.3% (21/65) in non-coaxial group and 36.6% (26/71) in coaxial group. Pulmonary hemorrhage in the majority of cases was treated conservatively. ConclusionPulmonary hemorrhage complicating CT-guided core biopsy of pulmonary lesions, showed insignificant difference between coaxial and non-coaxial techniques. Significant risk factors of pulmonary hemorrhage included small and basal lesions, increased lesion's depth from pleural surface, increased length of aerated lung parenchyma crossed by biopsy needle and passing through vessels within the lung during puncture.

Temperature profiles of sleeveless and coaxial phacoemulsification

To study the temperature profile at the corneal wound during 2 sleeveless techniques versus 2 coaxial phacoemulsification techniques. Department of Ophthalmology, Meir Medical Center, Kfar Saba and Ein-Tal Eye Center, Tel-Aviv, Israel. Experimental study. Thirty-six porcine eyes were randomized into 4 groups: Group 1: conventional coaxial system (3.0 mm incision); Group 2: coaxial microincision cataract surgery (MICS) system (2.2 mm incision); Group 3: bimanual MICS (1.1 mm incision); Group 4: sleeveless tri-MICS (1.1 mm incision) using a 19-gauge anterior chamber maintainer as the sole fluid source. Temperature measurements were taken using a thermocouple and an infrared thermal imaging system. Measurements were taken in 2 settings; that is, with and without occlusion. With no occlusion, corneal burns did not occur in any group. However, corneal temperatures were lower with the sleeveless systems (Groups 3 and 4) than with the coaxial systems (Groups 1 and 2) (P=.0003). When occlusion was induced, temperatures were kept constantly low in the sleeveless groups, whereas in the coaxial groups, temperatures increased rapidly, causing corneal burns within seconds. The mean temperature elevations at the incision sites were 39 °C, 48.5 °C, 13.6 °C, and 11.3 °C in Groups 1, 2, 3, and 4, respectively (P<.0001). Sleeveless phacoemulsification maintained lower tissue temperatures than sleeved coaxial methods. During occlusion, fluid flow around the naked tip of the sleeveless systems prevented heat accumulation and corneal burns.

Controlled release behaviour of protein-loaded microparticles prepared via coaxial or emulsion electrospray

Biodegradable poly (lactic-co-glycolic acid) (PLGA) microparticles are an effective way to achieve sustained drug release. In this study, we investigated a sustained release model of PLGA microparticles with incorporated protein via either emulsion or coaxial electrospray techniques. PLGA (75:25) was used as the carrier, and bovine serum albumin as a model protein. Coaxial electrospray resulted in a type of core–shell structure with mean diameters of 2.41 ± 0.60 µm and a centralised protein distribution within the core. Emulsion electrospray formed bigger microparticles with mean diameters of 22.75 ± 8.05 µm and a heterogeneous protein distribution throughout the microparticles. The coaxial electrospray microparticles presented a much slighter burst release than the emulsion electrospray microparticles. Loading efficiency was significantly higher (p < 0.05) in the coaxial group than emulsion group. This indicated that both emulsion and coaxial electrospray could produce protein-loaded microparticles with sustained release behaviour, but the former revealed a superior approach for drug delivery.

CT-guided transthoracic cutting needle biopsy of intrathoracic lesions: Comparison between coaxial and single needle technique

To evaluate the complication rates and diagnostic accuracy of two different CT-guided transthoracic cutting needle biopsy techniques: coaxial method and single needle method. This study involved 198 consecutive subjects with 198 intrathoracic lesions. The first 98 consecutive subjects received a single needle cutting technique and the next 100 consecutive subjects received a coaxial technique. Both groups were compared in relation the diagnostic accuracy and complication rates. No significant difference was found between the two groups concerning patient characteristics, lesions and procedure variables. There was a borderline statistical difference in the incidence of pneumothorax at within 24-h post biopsy between patients in the single needle group (5%) and the coaxial group (13%) (P=0.053). Little difference was found in the pneumothorax rate at immediately post biopsy between the two groups, which was 28% in the single needle group and 31% in the coaxial group. There was no significant difference in the hemoptysis rate between the two groups, which was 9.2% in the single needle group and 11% in the coaxial group. Both techniques yielded an overall diagnostic accuracy of 98% for malignant lesions with similar sensitivity (single needle: 96.9% vs. coaxial: 96.4%) and specificity (single needle: 100% vs. coaxial: 100%). There is little difference in the pneumothorax rates and bleeding complications between patients who either received a single needle or a coaxial transthoracic cutting biopsy. Both techniques produce an overall diagnostic accuracy of 98% for malignant lesions.

Factors influencing corneal biomechanical changes after microincision cataract surgery and standard coaxial phacoemulsification

To determine the factors affecting corneal biomechanics using biomechanical waveform analysis after microincision cataract surgery (MICS) and standard coaxial phacoemulsification with different incision sizes. Vissum-Instituto Oftalmologico de Alicante, Alicante, Spain. This prospective nonrandomized study comprised eyes with significant cataract that had MICS (sub-1.8 mm incision) or coaxial phacoemulsification (2.75 mm incision). Corneal hysteresis (CH) and the corneal resistance factor (CRF) were measured by biomechanical waveform analysis (Ocular Response Analyzer) preoperatively, immediately postoperatively, and at 1 month. Results were analyzed and compared between groups. In the MICS group (n = 30), there was a significant increase in Goldmann-correlated intraocular pressure (IOP) and corneal-compensated IOP, although CH decreased in the immediate postoperative period (P<.05). At 1 month, all parameters in the MICS group returned to normal. The coaxial group (n = 30) had an increase in Goldmann-correlated IOP and corneal-compensated IOP, both of which were higher than normal at 1 month. Backward multiple regression analysis showed significant correlations between CH and preoperative Goldmann-correlated IOP and preoperative CRF (r(2) = 0.631, P<.05); between age, axial length (AL), and preoperative CRF (r(2) = 0.418, P<.05); and between the change in CH and AL, total incision length, and preoperative CH (r(2) = 0.429, P<.05). Cataract surgery with MICS and coaxial phacoemulsification significantly altered corneal biomechanics. Corneal hysteresis was inversely correlated with Goldmann-correlated IOP; CRF was inversely correlated with age and AL. The MICS technique provided more stable corneal biomechanical properties than standard coaxial phacoemulsification 1 month postoperatively.

Coaxial, microcoaxial, and biaxial microincision cataract surgery: Prospective comparative study

To compare the intraoperative and postoperative results of 3 phacoemulsification techniques. Atatürk Training and Research Hospital, 2nd Ophthalmology Department, Ankara, Turkey. In this prospective randomized study, patients had standard coaxial (2.8 mm incisions), microcoaxial (2.2 mm incisions), or biaxial microincision (1.2 to 1.4 mm trapezoidal incisions) phacoemulsification. Intraoperative phaco parameters and total surgical time were measured and complications recorded. Postoperative visual acuity improvement, pachymetric differences, and surgically induced astigmatism (SIA) results were compared. Each group comprised 45 eyes. There were no significant differences between the 3 groups in demographic, morphologic, or preoperative surgical data. The mean effective phaco time was 2.56 seconds +/- 2.46 (SD) in the standard coaxial group, 1.98 +/- 1.91 seconds in the microcoaxial group, and 1.29 +/- 1.85 seconds in the biaxial microincision group (P<.05). The mean total surgical time was 14.48 +/- 4.21 minutes, 13.01 +/- 3.66 minutes, and 18.79 +/- 6.58 minutes, respectively (P<.01), and the mean measured final incision size was 2.83 +/- 0.11 mm, 2.26 +/- 0.07 mm, and 1.89 +/- 0.21 mm, respectively. The mean SIA 90 days postoperatively was 0.46 diopter (D), 0.24 D, and 0.13 D, respectively (P<.01). There was no statistically significant difference in the complication rate, visual acuity gain, or pachymetric change between the groups (P>.05). All 3 techniques were reliable, functional, and effective, yielding good visual outcomes and low phaco parameters and complication rates. Biaxial microincision surgery, with the smallest incisions, induced less astigmatism and reduced all intraoperative phaco parameters except total surgical time.

Biaxial microincision versus coaxial small-incision cataract surgery in complicated cases

To evaluate and compare the results of biaxial microincision and coaxial small-incision surgery in patients with cataract with coexisting exfoliation syndrome, uveitis, anterior or posterior synechias, phacodonesis, or previous intraocular surgery over an 8-week follow-up. Department of Ophthalmology, Mainz University, Mainz, Germany. Eyes were prospectively assigned (1:1) to have biaxial microincision (<1.5 mm) phacoemulsification or coaxial small-incision (2.8 mm) phacoemulsification using pulsed ultrasound energy (Sovereign WhiteStar) with variable duty cycles followed by implantation of a microincision intraocular lens. Intraoperative and postoperative complications, corrected distance visual acuity (CDVA), laser flare photometry values, effective phacoemulsification time (EPT), and endothelial cell count (ECC) were evaluated. The study enrolled 94 eyes. There were no statistically significant differences between the techniques in intraoperative or postoperative complications. The most frequent postoperative complications were corneal edema surrounding the incision (40%, biaxial group; 35%, coaxial group), pupil distortion (3% versus 7%), and fibrin exudation (3% versus 3%). No other postoperative complications occurred. The median EPT was statistically significantly shorter (1.34 seconds versus 5.4 seconds) and the median phaco power significantly lower (3.3% versus 12.9%) in the biaxial group than in the coaxial group (P<.001). There were no differences between groups in CDVA, laser flare photometry values, or ECC. The EPT was shorter and the mean phaco power lower with biaxial phacoemulsification, perhaps because of better access of the phaco handpiece for grooving the nucleus with this technique. The 2 techniques were comparable in intraoperative and postoperative complications. No other author has a financial or proprietary interest in any material or method mentioned.

Optical coherence tomography of macular thickness after biaxial vs coaxial microincision clear corneal cataract surgery

To evaluate macular thickness changes after biaxial microincision versus coaxial small incision cataract surgery using optical coherence tomography (OCT). This prospective, randomized, marked study comprised 70 patients (70 eyes) undergoing biaxial microincision surgery or conventional coaxial phacoemulsification. Patients were evaluated by Stratus OCT preoperatively and 1 day, 4 weeks, and 8 weeks postoperatively. Best-corrected visual acuity (BCVA), phacoemulsification power, and effective phacoemulsification time (EPT) were evaluated. In the biaxial group, median foveal thickness changed from 160 microm preoperatively to 168 microm 8 weeks postoperatively (p=0.018), while median macular volume increased from 2.43 mm3 to 2.57 mm3 (p<0.001). In the coaxial group, median foveal thickness increased from 164 microm preoperatively to 170 microm 8 weeks postoperatively (p=0.082), while median macular volume changed from 2.45 mm3 to 2.55 mm3 (p<0.001). No significant differences in the intraindividual increase of foveal thickness and macular volume were found between groups at 8 weeks. A statistically significant difference between groups was found in median foveal thickness at day 1 postoperatively (p=0.027). No significant differences between groups in median macular volume were found at day 1 or at 4 and 8 weeks postoperatively. Median phacoemulsification power was 7.1% and EPT 2.4 seconds in the biaxial group versus 10.6% and 3.2 seconds in the coaxial group (p<0.001 and p=0.078). No clinically relevant differences in foveal thickness or macular volume were observed after biaxial microincision and coaxial small incision clear corneal cataract surgery. The blood-retinal barrier did not seem to be influenced by either procedure.

Coaxial Group III−Nitride Nanowire Photovoltaics

Coaxial core/shell nanowires represent an important class of nanoscale building blocks with substantial potential for exploring new concepts and materials for solar energy conversion. Here, we report the first experimental realization of coaxial group III-nitride nanowire photovoltaic (PV) devices, n-GaN/i-In(x)Ga(1-x)N/p-GaN, where variation of indium mole fraction is used to control the active layer band gap and hence light absorption. Current-voltage data reveal clear diode characteristics with ideality factors from 3.9 to 5.6. Electroluminescence measurements demonstrate tunable emission from 556 to 371 nm and thus confirm band gap variations in the In(x)Ga(1-x)N active layer from 2.25 to 3.34 eV as In composition is varied. Simulated one-sun AM 1.5G illumination yielded open-circuit voltages (V(oc)) from 1.0 to 2.0 V and short-circuit current densities (J(sc)) from 0.39 to 0.059 mA/cm(2) as In composition is decreased from 0.27 to 0 and a maximum efficiency of approximately 0.19%. The n-GaN/i-In(x)Ga(1-x)N/p-GaN nanowire devices are highly robust and exhibit enhanced efficiencies for concentrated solar light illuminations as well as single nanowire J(sc) values as high as 390 mA/cm(2) under intense short-wavelength illumination. The ability to rationally tune the structure and composition of these core/shell III-nitride nanowires will make them a powerful platform for exploring nanoenabled PVs in the future.

Comparative quantification of ingress of trypan blue into the anterior chamber after microcoaxial, standard coaxial, and bimanual phacoemulsification: Randomized clinical trial

To compare ocular surface fluid ingress into the anterior chamber at the end of microcoaxial, standard coaxial, and bimanual phacoemulsification using trypan blue as the quantifying tracer. Iladevi Cataract and IOL Research Centre, Ahmedabad, India. This prospective randomized observational study comprised 180 consecutive patients who had microcoaxial, standard coaxial, or bimanual phacoemulsification. Trypan blue was applied over the conjunctival surface, and the amount of ingress was assessed after cortex removal (time point 1) and at the end of the surgery after intraocular lens insertion and stromal hydration (time point 2). Logs of dilution were used for statistical analysis. At time point 1, a statistically significant difference was observed in the ingress of trypan blue in the aqueous aspirate. The bimanual group had the highest ingress and the microcoaxial group, the lowest. The amount of ingress in the standard coaxial group fell between the other 2 groups (P< .001). At time point 2, there was no statistically significant difference between the microcoaxial group and the standard coaxial group (P = 1.00); however, in the bimanual group, trypan blue ingress was statistically significantly higher than in the other 2 groups (P< .001). At both time points, trypan blue ingress was statistically significantly higher in the bimanual group than in the standard coaxial and microcoaxial groups. At time point 2, there was no statistically significant difference between the standard coaxial and microcoaxial groups.

Cataract surgery using the bimanual phacoemulsification technique with an Accurus system and Mackool microphaco tip

To investigate the safety and effectiveness of the Accurus vitreoretinal and phacoemulsification system (Alcon, Inc.) for bimanual phacoemulsification surgery. Kosei Chuo Hospital, Tokyo, Japan. Phacoemulsification for age-related cataract was performed using a bimanual technique in 55 eyes and a coaxial technique in 31 eyes. The Accurus system with a venturi pump and a sleeveless ultrasonic tip or a Mackool microphaco tip was used in all cases. The 2 techniques were compared. In bimanual phacoemulsification, the 2 tips were evaluated to determine whether either reduced ocular tissue impairment. The mean best corrected visual acuity 1 day after the surgery was 20/20 in both groups. There was no significant difference between the bimanual group and coaxial group except in ultrasound output (bimanual 22%, coaxial 28%; P = .01). Iris impairment was observed only in the bimanual group but was reduced by the use of the Mackool sleeved microphaco tip. Bimanual phacoemulsification for cataract surgery using the Accurus system with a venturi pump and a Mackool microphaco tip was safe and effective and may provide a means of performing combined or successive cataract and vitreoretinal surgery.

Biaxial Microincision versus Coaxial Small-Incision Clear Cornea Cataract Surgery

To compare clinical outcomes of biaxial microincision (1.5 mm) and coaxial small-incision (2.75 mm) clear cornea cataract surgery. Randomized controlled clinical trial. Seventy eyes of 70 patients were examined at a German university eye hospital. The 70 patients (70 eyes) were assigned randomly (1:1) to a biaxial or conventional coaxial incision group. Both groups underwent phacoemulsification using pulsed ultrasound energy with variable duty cycles, followed by microincision intraocular lens implantation. Best-corrected visual acuity (BCVA), astigmatism, laser flare photometry value, effective phacoemulsification time (EPT), and endothelial cell count were evaluated. The treatment groups did not differ in baseline characteristics (median BCVA of 20/40 preoperatively in both groups, P = 0.97). On postoperative day 1, BCVA was better in the biaxial group than in the coaxial group (20/25 vs. 20/33, P = 0.018). Eight weeks after surgery, median BCVAs were 20/20 in the biaxial group and 20/25 in the coaxial group (P = 0.015). Median changes in astigmatism were -0.15 diopters (D) in the biaxial group and -0.31 D in the coaxial group. Neither clinically relevant nor statistically significant differences were found in laser flare photometry values. Effective phacoemulsification time was >3 seconds in only 34% of biaxial procedures, versus 68% of coaxial procedures (P = 0.013). At 8 weeks after surgery, endothelial cell counts were decreased similarly in the biaxial (14.5%) and coaxial (14.1%) groups (P = 0.408). With the biaxial microincision technique, EPT is shorter and BCVA improves more rapidly, with no difference in astigmatism, laser flare photometry results, or endothelial cell count relative to the coaxial small-incision technique for phacoemulsification.