Difference In Defect Size Research Articles

Differences in the Severity and Location of Patellofemoral Cartilage Damage Between Instability Patients With and Without Patella Alta.

Patella alta is a risk factor for recurrent patellar instability. Differences in chondral injury in patients with patellar instability between patella alta and patella norma have not been evaluated. To analyze whether preoperative cartilage damage differs in severity and location between patellar instability patients with and without patella alta. Cohort study; Level of evidence, 3. Patients with patellar instability who underwent patellar realignment surgery at a single institution with preoperative magnetic resonance imaging (MRI) scans were included. After measurement of Caton-Deschamps index (CDI) on MRI, patients were divided into patella alta (CDI ≥1.3) and patella norma groups. The area measurement and depth and underlying structures (AMADEUS) score was used to quantify cartilage defect severity on MRI. A total of 121 patients were divided into patella alta (n = 50) and patella norma (n = 71) groups. The groups did not differ significantly in sex ratio, age at MRI, body mass index, mean reported number of previous dislocations, or mean interval between first reported dislocation and date of MRI. A total of 34 (68%) of the patella alta group and 44 (62%) of the patella norma group had chondral defects (P = .625) with no significant between-group differences in defect size (P = .419). In both groups, chondral injuries most affected the medial patellar facet (55% in patella alta vs 52% in patella norma), followed by the lateral facet (25% vs 18%), and lateral femoral condyle (10% vs 14%). A smaller proportion of patients had full-thickness defects in the patella alta compared with the patella norma group (60% vs 82%; P = .030). The overall AMADEUS score was higher for the patella alta versus the patella norma group (68.9 vs 62.1; P = .023), indicating superior articular cartilage status. Patients with patella alta had less severe cartilage injury after patellar instability, including a lower proportion with full-thickness defects and better overall cartilage grade. The location of injury when present was similar between alta and norma, with most defects affecting the medial facet, lateral facet, and lateral femoral condyle in descending frequency.

Transcatheter atrial septal defect closure late after completion of biventricular circulation in patients with pulmonary atresia intact ventricular septum or critical pulmonary stenosis.

This study aimed to explore anatomical and hemodynamic features of atrial septal defect, which was treated by transcatheter device closure late after completion of biventricular circulation in patients with pulmonary atresia and intact ventricular septum (PAIVS) or critical pulmonary stenosis (CPS). We studied echocardiographic and cardiac catheterization data, including defect size, retroaortic rim length, single or multiple defects, the presence of malalignment atrial septum, tricuspid and pulmonary valve diameters, and cardiac chamber sizes, in patients with PAIVS/CPS who underwent transcatheter closure of atrial septal defect (TCASD), and compared to control subjects. A total of 173 patients with atrial septal defect, including 8 patients with PAIVS/CPS, underwent TCASD. Age and weight at TCASD were 17.3 ± 18.3 years and 36.6 ± 13.9 kg, respectively. There was no significant difference in defect size (13.7 ± 4.0 vs. 15.6 ± 5.2 mm, p = 0.317) and the retro-aortic rim length (3.7 ± 4.3 vs. 3.6 ± 0.3.1 mm, p = 0.948) between the groups; however, multiple defects (50% vs. 5%, p < 0.001) and malalignment atrial septum (62% vs. 14%. p < 0.001) were significantly frequent in patients with PAIVS/CPS compared to control subjects. The ratio of pulmonary to systemic blood flow in patients with PAIVS/CPS was significantly lower than that in the control patients (1.2 ± 0.4 vs. 2.0 ± 0.7, p < 0.001); however, four out of eight patients with atrial septal defect associated with PAIVS/CPS had right-to-left shunt through a defect, who were evaluated by the balloon occlusion test before TCASD. The indexed right atrial and ventricular areas, the right ventricular systolic pressure, and mean pulmonary arterial pressure did not differ between the groups. After TCASD, the right ventricular end-diastolic area remained unchanged in patients with PAIVS/CPS, whereas it significantly decreased in control subjects. Atrial septal defect associated with PAIVS/CPS had more complex anatomy, which would be a risk for device closure. Hemodynamics should be individually evaluated to determine the indication for TCASD because PAIVS/CPS encompassed anatomical heterogeneity of the entire right heart.

Impact of Body Mass Index (BMI) on perioperative outcomes following minimally invasive retromuscular abdominal wall reconstruction: a comparative analysis.

Morbidity and recurrence rates are higher in obese patients undergoing open abdominal wall reconstruction (AWR). Historically, body mass index (BMI) ≥ 40 has served as a relative contraindication to open AWR. The purpose of this study is to evaluate the impact of minimally invasive surgery (MIS) on outcomes after AWR for higher versus lower BMI patients. A retrospective review of a prospectively maintained database was conducted of all patients who underwent MIS AWR between September 2015 and April 2019 at our institution. Patients were subdivided into two groups based on their BMI: BMI ≤ 35kg/m2 and BMI > 35kg/m2. Patient demographics and perioperative data were evaluated using univariate and multivariate analysis. 461 patients were identified and divided into two groups: BMI ≤ 35 (n = 310) and BMI > 35 (n = 151). The two groups were similar in age (BMI ≤ 35: 56.3 ± 14.1years vs. BMI > 35: 54.4 ± 11.9, p = .154). BMI > 35 group had more patients with ASA score of 3 (81% vs. 32%, p < .001) and comorbid conditions such as hypertension (70% vs. 45%, p < .001), diabetesmellitus (32% vs. 15%, p < .001), and history of recurrent abdominal wall hernia (34% vs. 23%, p = .008). BMI > 35 group underwent a robotic approach at higher rates (74% vs. 45%, p < .001). Patients who underwent a Rives-Stoppa repair from the higher BMI cohort also had a larger defect size (5.6 ± 2.4cm vs. 6.7 ± 2.4cm, p = .004). However, there were no differences in defect size in patients who underwent a transversus abdominus release (BMI ≤ 35: 9.7 ± 4.9cm vs. BMI > 35: 11.1 ± 4.6cm, p = .069). Both groups benefited similarly from a short length of stay, similar hospital charges, and lower postoperative complications. Initial findings of our data support the benefits of elective MIS approach to AWR for patients with higher BMI. These patients derive similar benefits, such asfaster recovery with low recurrence rates, when comparedto lower BMI patients, while avoiding preoperative hernia incarceration, postoperative wound complications, and hernia recurrences. Future follow-up is required to establish long-term perioperative and quality of life outcomes in this patient cohort.

Microstructure evolution and mechanical property response via 3D printing parameter development of Al–Sc alloy

ABSTRACT Three-dimensional (3D) printed Sc-modified Al alloy by powder bed fusion (PBF) provides significant strength and ductility without hot tearing during the process. This kind of 3D-printable high specific strength materials exhibits great potential in lightweight applications. Due to the lesser design limitation through the 3D printing process, the degree of lightweight is greatly affected by the specific strength of the materials. Hence, to further improve the mechanical properties of the material through process optimisation or post-treatment is of great importance. Microstructure feature variations due to different processing parameters are well known for traditional processes and materials. This study explores the parameter–microstructure–performance relationship of 3D printed Sc-modified Al alloys from the perspective of melt pool interactions. According to the stress concentration effect and Hall–Petch effect, the mechanical properties of the 3D printed materials vary greatly depending on the difference in defect size, shape and grain size.

Evaluation of Long-term Complications and Recurrence Rates in Ventral Hernia Repair With Component Separation

PURPOSE: Ventral hernia repair (VHR) with concomitant component separation (CS) achieves better structural support in large fascial defect abdominal wall reconstructions. Traditionally, CS is performed by plastic surgeons but has recently become more popular in other specialties such as general surgery. Previous reports indicate that although CS reduces hernia recurrence, it is associated with an increased risk of complications. This study evaluates outcomes associated with VHR with CS (VHR + CS) compared to VHR alone and a subanalysis of VHR + CS outcomes stratified by plastic versus general surgeons. METHODS: A retrospective chart review of all VHRs between January 2009 and June 2017 at a single institution was performed. Demographic data, comorbidities, procedure details, length of stay (LOS), postoperative complications, and recurrence rates were recorded. Patients with <6 months follow-up or <30 cm2 defect size were excluded. Follow-up was defined as surgical follow-up, abdominal computed tomography or magnetic resonance imaging, or surgical visits with well-documented abdominal examinations. RESULTS: A total of 185 patients were identified: group I (n = 42) received VHR + CS and group II (n = 143) received VHR alone. Differences in defect size (217.4 versus 149.2 cm2; P = 0.02) and concurrent procedures (1.4 versus 0.9; P = 0.02) between groups I and II, respectively, reached significance. In addition, group I had significantly increased LOS (group I 15.0 days versus group II 4.6 days; P = 0.0049); however, no difference in postoperative complications (22.7% versus 21.6%; P = 0.89) or recurrence rates (22.7% versus 14.1%; P = 0.052) between groups I and II, respectively, was appreciated. Group I (n = 42), who received VHR + CS, was further stratified by specialty; group IA (n = 24) VHR + CS was performed by plastic surgeons, and group IB (n = 18) VHR + CS was performed by general surgeons. Differences in defect size (262.8 versus 149.6 cm2; P = 0.046) and concurrent procedures (1.7 versus 0.9; P = 0.047) were noted in groups IA and IB, respectively. There were no differences in recurrence rate (20% versus 20%; P = 0.656), LOS (8.8 versus 6.3 days; P = 0.33), or complication rate (29.1% versus 27.8%; P = 0.6) in groups IA and IB, respectively. CONCLUSION: Despite the use of CS in larger, more complex VHRs in our overall patient population, VHR + CS provides comparable outcomes in abdominal wall reconstruction at our institution. In our subgroup analysis, VHR + CS performed by plastic surgeons showed no difference in LOS, complication rates, and recurrence rates compared to general surgeons, despite larger defect sizes, more concurrent procedures, and more complex reconstructions performed in the plastic surgery cohort. Performance of VHR + CS is a viable approach to improving overall outcomes in patients with larger, complex hernias and may directly benefit from plastic surgery participation.

Head and neck soft tissue reconstruction with anterolateral thigh flaps with various components: Development of an algorithm for flap selection in different clinical scenarios.

The antero-lateral thigh free flap (ALT) is conventionally designed as a fasciocutaneous flap (FALT). However, the thickness of the flap can be designed in at least in two more variants: myocutaneous (MYALT), and myofascial (MALT). The aim of this study was to evaluate the use of ALT flap as a universal solution for head and neck soft tissue reconstruction and development of an algorithm for flap selection in different clinical scenarios. Forty patients, 29 males, 11 females, with mean age of 61.6 years (range 36-77) were enrolled. Thirty-three patients were affected by mucosal squamous cell carcinoma (24 oral cavity, 8 larynx, 1 hypopharynx), four by cutaneous squamous cell carcinoma, two by sarcoma of the orbit, one by adenoid cystic carcinoma of the parotid gland. MALT was used for tongue reconstructions thicker than 2 cm. When vastus lateralis was not thick enough we used MYALT, which was used for bulky head and neck reconstruction requiring mucosa and/or skin. FALT was performed for oral and mucosal defects thinner than 2 cm. We performed 19 MYALT, 11 FALT, and 10 MALT. We proposed ALT reconstruction to all patients requiring soft tissue replacement, for this reason selection bias is excluded. Statistical analysis was conducted to analyze any difference in defect size, flap volume, functional, and cosmetic results. Overall mean follow-up was 18.9 months (range 3-48). Follow-up of single flaps was as follow: MALT 20.3 (range 3-48), MYALT 17.6 (range 4-45), FALT 19.1 (range 3-48), mean time of follow-up was not significant among the three groups (p .82). Mean size of the defect in cm3 was 188.5 (range 25-495), Mean sizes of the defects were: tongue 177.7 (range 48-360), oral floor/check 128.3 (range 25-432), larynx hypopharynx 315.7 (range 184-495), and maxilla 232.0 (range 224-240). Mean volume difference was significantly different between oral floor defects and larynx/hypopharynx (mean volume difference 187.4 95% CI -352.0-2.7 p < .001). Mean sizes of the flaps in cm3 were: FALT 51.5 (range 25-72), MYALT 270.7 (range 90-495), and MALT 250.0 (range 90-495). Mean volume difference was significantly different among the three groups (p < .001). No major complications were experienced, four minor complications were reported (2/19 in MYALT, 1/10 MALT, 1/10 FALT) and results were not significant among the three groups (p .20). Gastrostomy tube dependence occurred in 4/19 (21%) of tongue cases, and none in all the other cases (p < .001). Speech was unintelligible in 3/19 (16%) of patients with tongue reconstruction, 1/7 (15%) of patients with larynx/hypopharynx reconstruction, and none regarding the other defects reconstructed (p < .001). Cosmesis was poor in 2/19 (11%) of tongue cases, and acceptable or higher in the other cases (p < .001). Tracheostomy dependence rate was 27% (7/7 patients submitted to a total laryngectomy with hypopharyngectomy and 4/19 patients submitted to total glossectomy, p < .001). ALT offers unique advantages in head and neck reconstruction, including adequate bulk when needed, different coating surfaces, and optimal functional results with minimal morbidity. On the base of our case series, which showed that the ALT flap is highly versatile and a successful reconstructive option, we propose a decision making-flow chart in order to choose the best specific flap variant adequate for every specific clinical scenario.

Factors Affecting Early Single Heel Raise after Repair of Achilles Tendon Rupture

Category: Sports Introduction/Purpose: No physical exam or clinical test can clearly predict a final course of acute Achilles tendon rupture after surgical treatment. But, in recent studies, ability to perform single-heel-raise during the early postoperative period was considered as a significant prognostic factor. Therefore, analysis of the relationship between preoperative factors and timing of the single heel raise might help to predict the prognosis and aid to establish an individualized rehabilitation plan. The purpose of this study was to analyze the factors affecting early single heel raise after surgical treatment of acute Achilles tendon rupture. Methods: From January 2012 to August 2015, a retrospective analysis was performed for 68 patients who met the inclusion criteria among 98 cases of surgically treated acute Achilles tendon rupture. Operative technique and rehabilitation protocol were same in all cases. The patients who were able to perform a single heel raise within 3 months postoperatively were classified into the study group and the rest was determined as the control group. During periodic outpatient observation, we evaluated Achilles tendon total rupture score (ATRS), Visual Analog Scale (VAS), and timing capable of a single heel raise. We also preoperatively measured defect size and distance between calcaneal osteotendinous junction and rupture site by ultrasound image in all cases. Results: No difference was found in demographic factors between the study group (23 cases) and the control group (45 cases) who performed a single heel raise later than 3 months postoperatively. There were no significant difference in defect size and distance between calcaneal osteotendinous junction to the rupture site (P=0.38, P=0.63). However, when the rupture site was divided into hyporvascular zone (from calcaneal osteotendinous junction to the rupture site: 4~7 cm) and hypervascular zone, the study group showed a significantly low hyporvascular zone rupture rate. (14/23, 41/45, P=0.003). Also, in the logistic regression analysis that included age, BMI, smoking, hyporvascular zone rupture, defect size, and operation delay, patients with hypervascular region rupture showed odds ratio of 5.3 (P=0.017) in performing a single heel raise within postoperative 3 month. ATRS score at postoperative 3 months and last f/u were significantly higher in the study group. (p&lt;0.01) Conclusion: Achilles tendon rupture at hypovascular zone is a poor prognostic factor for the early single heel raise and might significantly affect the prognosis after acute Achilles tendon rupture operation.

High-Sensitivity and High-Resolution SPECT/CT Systems Provide Substantial Dose Reduction Without Compromising Quantitative Precision for Assessment of Myocardial Perfusion and Function

There is increasing concern about radiation exposure from myocardial perfusion SPECT (MPS). γ-cameras with solid-state cadmium-zinc-telluride (CZT) detectors have better count sensitivity and spatial resolution than conventional sodium iodine detectors, allowing for significant reductions in radiotracer dose or acquisition time. This study aimed to demonstrate the capability of a hybrid CZT SPECT/64-slice CT system for dose reduction and to determine the maximal reduction possible without compromising image quality or the quantification precision of clinical MPS. The imaging data of patients with normal myocardial perfusion and 30 patients with mid-sized to large perfusion defects who had undergone stress (99m)Tc-tetrofosmin MPS were postprocessed. Low-dose (361 ± 60 MBq) and high-dose (725 ± 142 MBq) (99m)Tc-tetrofosmin scans were included, with 6-min and 4-min scanning times, respectively. List-mode SPECT data were reconstructed with CT-based attenuation correction and with full as well as 50% and 75% reductions in acquisition time to simulate the corresponding relative dose reductions. The reconstructed SPECT images were analyzed to calculate global MPS defect size and regional defect size for 3 coronary artery territories-left anterior descending, left circumflex, and right-as well as left ventricular (LV) volume and ejection fraction. For patients with normal MPS results, there were no differences in defect size, LV volume, or ejection fraction, regardless of whether 50% or 75% reduction was used. For patients with abnormal MPS results, at a 50% reduction there was a significant difference in global defect size but not in regional defect size in the left anterior descending, left circumflex, and right coronary artery territories, whereas at a 75% reduction the difference was statistically significant in all territories, including the difference in global defect size. Nonetheless, differences in the defect size were minimal. The LV end-diastolic and end-systolic volumes and LV ejection fraction were not significantly different, regardless of whether 50% or 75% dose reduction was used. Ultra-low-dose (<190 MBq) MPS even with short imaging times (<6 min) is feasible using a hybrid CZT SPECT/CT camera without compromising image quality or significantly altering quantification of myocardial perfusion or LV function. We demonstrated that an additional 50% reduction in the current low-dose recommendations from the American Society of Nuclear Cardiology guidelines for (99m)Tc-labeled MPS is highly feasible while retaining short imaging protocols.

Comparative evaluation of Comfilcon A and Senofilcon A bandage contact lenses after transepithelial photorefractive keratectomy

PurposeTo evaluate and compare Comfilcon A and Senofilcon A silicone hydrogel contact lenses used as a therapeutic bandage following transepithelial excimer laser photorefractive keratectomy (PRK). MethodsPatients undergoing transepithelial PRK for myopia were prospectively recruited. Included patients had a Comfilcon A silicone hydrogel lens inserted in one eye, with a Senofilcon A lens in the contralateral eye. Postoperative assessment of subjective pain, epithelial healing and visual recovery was at day 1, 3 and 7. Contact lens factors including centration, movement and deposits were assessed. Results48 eyes of 24 patients were included in the study. Mean age was 31 years (SD 11) and mean refractive error −4.5 D (SD 1.8). Mean pain score at day 1 was significantly higher in the Comfilcon group at 4.6 (SD 2.7) vs. 1.5 (SD2.5) in the Senofilcon group (P<0.005). Mean time to healing was 3.17 days (SD 0.37) in the Comfilcon group, and 3.21 days (SD 0.4) in the Senofilcon group, with no difference in defect size. There was a pronounced central raphe in 1 eye in the Comfilcon group vs. 5 eyes in the Senofilcon group (P=0.19). Significantly more eyes demonstrated no lens movement in the Senofilcon group (18 vs. 4, P=0.0001). ConclusionThe variation in material characteristics and lens geometry of different silicone hydrogel lenses affects their clinical characteristics in therapeutic roles. Other factors than oxygen permeability may affect pain and epithelial healing, with superior pain relief from the less permeable Senofilcon lens in this study.

Soft tissue response to fenestration type defects in the gingiva treated with various barrier membranes for regeneration

Background/purposeA few studies have compared the osteopromotive effect of different membranes, but soft tissue response to various membranes has not been thoroughly investigated. The purpose of this study was to investigate the impact of various exposed regenerative membranes on gingival soft tissue healing. Materials and methodsTen adult Taiwan dogs weighing 10–12 kg were used. After administration of local anesthesia, buccal gingival areas of the maxillary canines on both sides were disinfected with β-iodine. Punch-out lesions of 5 mm2 × 5 mm2 were made, 3 mm away from the gingival margin, using a 5-mm punch. Various barrier membranes (7 mm2 × 7 mm2) were placed under the mucoperiosteal flap. Test membrane materials included collagen, expanded polytetrafluoroethylene (e-PTFE), and high density PTFE (n-PTFE). The sites without barriers served as controls. The lesions were measured and photographed 1 week and 2 weeks after surgery. Histologic sections were prepared at 2 weeks to observe barrier-tissue integration and the inflammatory condition. ResultsThe lesion size in the collagen group decreased in 1 week and the lesions almost completely healed in 2 weeks as compared with the control group. Lesion size increased 1 week after surgery for both groups of e-PTFE and n-PTFE. ANOVA analysis of the 1-week lesions showed that the differences in defect size among the four groups were statistically significant (P < 0.001). A posthoc test (Bonferroni) showed that the differences between collagen and n-PTFE, between control and n-PTFE, and between e-PTFE and n-PTFE were significant. The other three pair-wise comparisons among collagen, control, and e-PTFE were nonsignificant. Lesion size and inflammatory reaction increased for the nonexfoliated sites. Histologic examination of the punch-out tissue margin of e-PTFE group showed ingrowth of fibrous connective tissue. No tissue integration was observed in the n-PTFE group. Compared with the control group, complete regeneration of oral epithelium was observed and the collagen membrane appeared intact 2 weeks following surgery. ConclusionIn the present study, collagen membranes may promote punch-out soft tissue healing whereas e-PTFE and n-PTFE interfered with healing. The impact of soft tissue healing on the efficacy of guided bone regeneration deserves further evaluation.

Effect of Welding Method on Weld Defects of ADB610 Steel

Statistical analysis was carried on weld defects of low carbon bainite ADB610 steel using shielded metal arc welding (SMAW) and mixed active-gas arc welding (MAG). By Pareto diagram analysis, although the ratio of porosity air hole using SMAW is slightly higher than the one using MAG, there is no qualitative difference in ADB610 steel weld defect types between two welding methods. And the crack occurs seldom, which indicates ADB610 steel has lower crack-sensitivity using SMAW and MAG. By histogram analysis and rank test, it can be concluded that there is distinctive difference in defect size between SMAW and MAG, and the average size using SMAW is bigger than the one using MAG. So if possible, MAG is recommended for low carbon bainite ADB610 steel.

Positron emission tomography detects evidence of viability in rest technetium-99m sestamibi defects

Objectives. The purpose of this study was to determine the relative value of single-photon emission computed tomographic (SPECT) imaging at rest using technetium-99m methoxyisobutyl isonitrile (technetium-99m sestamibi) with positron emission tomography for detection of viable myocardium.Background. Recent studies comparing positron emission tomography and thallium-201 reinjection with rest technetium-99m sestamibi imaging have suggested that the latter technique underestimates myocardial viability.Methods. Twenty patients with a previous myocardial infarction underwent rest technetium-99m sestamibi imaging and positron emission tomography using fluorine (F)-18 deoxyglucose and nitrogen (N)-13 ammonia. In each patient, circumferential profile analysis was used to determine technetium-99m sestamibi, F-18 deoxyglucose and N-13 ammonia activity (expressed as percent of peak activity) in nine cardiac segments and in the perfusion defect defined by the area having technetium-99m sestamibi activity <60%. Technetium-99m sestamibi defects were graded as moderate (50% to 59% of peak activity) and severe (<50% of peak activity). Estimates of perfusion defect size were compared between technetium-99m sestamibi and N-13 ammonia.Results. Sixteen (53%) of 30 segments with moderate defects and 16 (47%) of 34 segments with severe defects had ≥60% F-18 deoxyglocose activity considered indicative of viability. Fluorine-18 deoxyglucose evidence of viability was still present in 50% of segments with technetium-99m sestamibi activity <40%. There was no significant difference in the mean (± SD) technetium-99m sestamibi activity in segments with viable (40 ± 7%) and nonviable segments (49 ± 7%, p = 0.84). Of the 18 patients who had adequate F-18 deoxyglucose studies, the area of the technetium-99m sestamibi defect was viable in 5 (28%). In 16 patients (80%), perfusion defect size determined by technetium-99m sestamibi exceeded that measured by N-13 ammonia. The difference in defect size between technetium-99m sestamibi and N-13 ammonia was significantly greater in patients with viable (21 ± 9%) versus nonviable segments (7 ± 9%, p = 0.007).Conclusions. Moderate and severe rest technetium-99m sestamibi defects frequently have metabolic evidence of viability. Technetium-99m sestamibi SPECT yields larger perfusion defects than does N-13 ammonia positron emission tomography when the same threshold values are used.