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1.
Opt Lett ; 49(4): 939-942, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38359221

RESUMEN

Lithium niobate (LN)-based modulators offer superior modulation performances, including high-speed modulation, linearity, and temperature stability. However, these devices exhibit larger sizes due to the low light-matter interaction despite a significant electro-optic coefficient. In this work, we present a compact LN-based modulator using a plasmonic mode that confines the optical mode in a very narrow gap. By filling the gap with LN, the confinement factor in the LN is significantly enhanced. The proposed modulator provides an extremely small half-wave voltage-length product, VπL of 0.02 V/cm at an optical communication wavelength (λ = 1.55 µm). The proposed modulator scheme can be utilized in a wide range of optical communication devices that demand small footprints and a high-speed operation.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38895851

RESUMEN

PURPOSE: Whether the longevity of total knee arthroplasty (TKA) differs between postoperative phenotypes has not been investigated. This study aims to examine which phenotype has a worse long-term survival rate than the reference phenotype (neutral alignment-parallel joint line), and whether joint-line obliquity (JLO) affects the survivorship of TKA. METHODS: A total of 945 knees that underwent primary TKAs for primary osteoarthritis from January 2000 to January 2009 were included. These were classified into nine postoperative phenotypes based on the combined assessment of the hip-knee-ankle (HKA) angle and JLO, measured on standing radiographs. The 5-, 10- and 15-year survival rates were analysed using Kaplan-Meier methods and log-rank tests. The long-term survival rates of each phenotype were compared with the reference phenotype. RESULTS: There were 55 aseptic mechanical failures within a period of 10.4 ± 5.0 years. The most frequently observed phenotypes were the reference phenotype (n = 527), neutral alignment-lateral joint-line inclination (n = 162), varus alignment-lateral joint-line inclination (n = 104) and varus alignment-parallel joint line (n = 101). The overall failure rate for each phenotype was 3.6%, 3.7%, 18.3% and 7.9%, respectively. Only the 10- and 15-year survival rates of the varus alignment-lateral joint-line inclination phenotype were significantly different from those of the reference phenotype (97%-93% vs. 90%-69%; p = 0.017, <0.001). CONCLUSION: The lateral joint-line inclination phenotype had an inferior long-term survival rate after varus-aligned TKA. This suggested that alignment and JLO affected the long-term survival rate of patients who underwent TKA. LEVEL OF EVIDENCE: Level III, Retrospective cohort study.

3.
Clin Anat ; 35(6): 820-823, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35665540

RESUMEN

Hyaluronic acid filler injection is a minimally invasive procedure for facial rejuvenation that involves injecting filling materials to correct the volume or augment specific areas in the face. Deep nasolabial folds are a common concern in aging people. The simplest way to correct a deep nasolabial fold to rejuvenate the face is to inject Ristow's space with hyaluronic acid fillers. However, conventional injection methods, such as percutaneous injections using a needle, can cause severe complications, such as skin necrosis or blindness due to intravascular injections. Therefore, the aim of the present study was to introduce a safe technique for intraoral filler injections in deep nasolabial folds and review related anatomic features to evaluate the safety of this technique.


Asunto(s)
Técnicas Cosméticas , Envejecimiento de la Piel , Técnicas Cosméticas/efectos adversos , Humanos , Ácido Hialurónico , Inyecciones , Surco Nasolabial , Resultado del Tratamiento
4.
Clin Anat ; 35(5): 682-685, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35445437

RESUMEN

The skin barrier effectively inhibits the penetration of substances; therefore, drug delivery, especially the delivery of drugs that are hydrophilic, through the skin, is challenging. Objectives: Physicians in the esthetic field now use the transdermal drug delivery system to attempt to deliver esthetic materials, such as hyaluronic acid and poly-DL-lactic acid into the skin. Conventionally, esthetic physicians manually injected these materials using needle syringes into the dermis layer. However, the injection is often irregular, imprecise, slow, and painful. Injector devices have been developed to overcome these limitations. A total of five Korean cadavers (that of three men and two women with a mean age of 69.2 years; range, 60-73 years) underwent laser injection. We used a device called Er:YAG LASER to create the pressure needed for microjet delivery to the skin of the cadaver. Discussion: In this study, the first LASER pressure-based, needle-free microjet injector was used to deliver drugs effectively into the dermis of a cadaver. This study showed that a novel needle-free microjet injector using Er:YAG LASER can introduce beneficial, liquid, esthetic drugs into the papillary dermal layer (depth of 300um) with minimal epidermal damage.


Asunto(s)
Láseres de Estado Sólido , Administración Cutánea , Anciano , Cadáver , Sistemas de Liberación de Medicamentos , Femenino , Humanos , Láseres de Estado Sólido/uso terapéutico , Preparaciones Farmacéuticas , Piel
5.
Surg Radiol Anat ; 43(12): 2071-2076, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34432130

RESUMEN

PURPOSE: An antegrade approach is frequently used in catheter-directed thrombolysis to remove deep-vein thrombosis. However, the antegrade approach is difficult when accessing veins with small diameters; therefore, understanding the variation of deep calf vein is important. METHODS: This study measured the diameters and surface areas of the proximal and distal posterior tibial vein, peroneal vein, and anterior tibial vein to determine which are preferable for venous access. This study dissected 132 legs from Korean and Thai cadavers. The proximal and distal posterior tibial vein, peroneal vein, and anterior tibial vein were scanned and measured. RESULTS: The mean diameter and surface area were largest for the proximal tibial vein, at 6.34 mm and 0.312 cm2, respectively, followed by the anterior tibial vein (5.22 mm and 0.213 cm2), distal posterior tibial vein (3.29 mm and 0.091 cm2), and peroneal vein (3.43 mm and 0.081 cm2). The proximal posterior tibial vein and anterior tibial vein have large diameters and surface areas, which make them ideal for applying an antegrade approach in catheter-directed thrombolysis. CONCLUSIONS: The distal posterior tibial vein and peroneal vein are not recommended due to their smaller surface areas and also the anatomical variations therein.


Asunto(s)
Pierna/anatomía & histología , Pierna/irrigación sanguínea , Terapia Trombolítica/métodos , Adulto , Anciano , Anciano de 80 o más Años , Cadáver , Catéteres , Femenino , Humanos , Masculino , Persona de Mediana Edad , Terapia Trombolítica/instrumentación , Venas/anatomía & histología
6.
Arthroscopy ; 36(12): 3061-3068, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32721545

RESUMEN

PURPOSE: To compare the differences with respect to clinical and graft survivorship and patient-reported outcomes (PROs) between lateral (LMAT) and medial (MMAT) meniscus allograft transplantation. METHODS: Patients having a primary MAT between 1998 and 2016 were enrolled. The inclusion criteria were (1) patients who had a minimum 2-year follow-up and (2) patients who had magnetic resonance imaging (MRI) >2 years after surgery. Knees with localized grade 4 articular cartilage lesions >3 cm2 at the time of MAT were excluded. Clinical failure was defined as follows: modified Lysholm score <65, meniscectomy >50% of the graft, meniscectomy to the meniscocapsular junction zone, conversion to revision MAT, or realignment osteotomy or arthroplasty. Graft failure was defined as follows: tears involving >50% of the graft or unhealed peripheral rim observed on MRI. Kaplan-Meier survival analysis with log-rank test was used to compare survivorship between LMAT and MMAT. Patient-reported outcomes were compared based on the Hospital for Special Surgery, modified Lysholm, and International Knee Documentation Committee subjective scores collected preoperatively and at the final follow-up. RESULTS: A total of 299 knees (249 LMAT, 50 MMAT, mean age 33.0 ± 9.8 years) were included. Twenty clinical [2 MMAT (4.0%), 18 LMAT (7.2%)] and 24 graft [2 MMAT (4.0%), 22 LMAT (8.8%)] failures were identified. The mean clinical follow-up period was 63.1 ± 43.1 months (range 2 to 248), and MRI follow-up period was 62.6 ± 43.8 months (range 2 to 248). No significant differences in clinical and graft survivorship were found between the LMAT and MMAT groups (P = .481, P = .271, respectively). PROs preoperatively and at last follow-up also showed no significant difference between the groups. CONCLUSION: No significant differences in clinical survivorship, graft survivorship, and PROs were found between the LMAT and MMAT groups. LEVEL OF EVIDENCE: Level III, retrospective comparative study.


Asunto(s)
Supervivencia de Injerto , Articulación de la Rodilla/cirugía , Meniscos Tibiales/trasplante , Adolescente , Adulto , Aloinjertos , Cartílago Articular/patología , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Meniscectomía/métodos , Persona de Mediana Edad , Medición de Resultados Informados por el Paciente , Estudios Retrospectivos , Trasplante Homólogo/métodos , Adulto Joven
9.
Surg Radiol Anat ; 38(1): 49-54, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26168856

RESUMEN

PURPOSE: The aim of the present study was to determine the reliability of optical coherence tomography (OCT) in detecting cracked teeth and its relative clinical effectiveness by comparing it with other diagnostic methods including conventional visual inspection, trans-illumination, and micro-computed tomography (micro-CT). METHODS: The reliability of swept source OCT (SS-OCT) was verified by comparing the number of detected crack lines on 109 surfaces of 61 teeth with those detected with other conventional methods. RESULTS: One to one comparison revealed that crack lines that were invisible with naked eyes could be found in SS-OCT images. The detection ability of SS-OCT was superior or similar to those of micro-CT (100.0 %) and trans-illumination. CONCLUSIONS: Crack lines shown in the SS-OCT images had distinct characteristics, and structural crack lines and craze lines could be distinguished in SS-OCT images. Thus, the detection ability of SS-OCT renders it an acceptable diagnostic device for cracked-tooth syndrome.


Asunto(s)
Síndrome de Diente Fisurado/diagnóstico , Tomografía de Coherencia Óptica , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
Discov Nano ; 19(1): 111, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38970699

RESUMEN

Experimental and simulation studies demonstrated that the initial voltage setting significantly influences the open-circuit voltage (VOC) in triboelectric nanogenerators (TENGs). Utilizing diode configurations, we consistently observed two distinct VOCs independent of the initial settings. A lower VOC corresponded to the surface voltage (VSurface), while a higher VOC was amplified by the product of the VSurface and the TENG's characteristic impedance ratio. Notably, a lower measurement system capacitance provided a more precise representation of the inherent characteristics of the TENG. Conversely, an increase in system impedance led to a convergence of the two VOCs and a reduction in their magnitudes relative to VSurface. These findings suggest that optimizing the initial/repeated charge balancing and minimizing capacitive loads are crucial for maximizing TENG output power in practical applications.

11.
Discov Nano ; 19(1): 52, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38503898

RESUMEN

We investigated the polarity dependence of a capacitive energy management circuit in a triboelectric nanogenerator (TENG) power system. In a half-wave rectifying circuit, the Simulation Program with Integrated Circuit Emphasis and analytical models show that the charge dump to the load varied depending on the polarity of the rectifying circuit even with the same charge output from TENG. Depending on the polarity of the rectifying circuit, a fast saturation of the direct current (DC) output voltage or a high DC output voltage was obtained. Experiments with a half-wave rectifier and Bennet doubler confirmed our simulation and theoretical results. The charge dump from the minimum capacitance of the separated TENG to the load capacitance and the charge dump from the maximum capacitance of the contacted TENG to the load resulted in asymmetric charging behavior. We concluded that it is necessary to analyze the TENG and the capacitive energy management circuit as a single system rather than considering them as independent units in the rectifying circuit of the TENG. This work can provide insights for the design of triboelectric energy harvesting systems.

12.
Orthop Traumatol Surg Res ; 110(2): 103787, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38070733

RESUMEN

BACKGROUND: The limb length change (LLC) after total knee arthroplasty (TKA) is especially significant in valgus deformity. The higher LLC could cause higher incidences of lower limb length discrepancy (LLD) and low clinical score. However, studies about LLC after TKA for valgus deformity are limited, and there are none on the relationship between LLC and fixed flexion deformity (FFD) in valgus deformity. HYPOTHESIS: (1) The amount of LLC would affect the postoperative LLD, (2) the improvement of fixed flexion deformity (FFD) would affect the amount of LLC, (3) The amount of LLC would affect the improvement in the clinical score after TKA for valgus deformity. PATIENTS AND METHODS: Fifty knees of 50 patients who underwent primary unilateral TKA for valgus-type osteoarthritis between January 2000 and October 2021 were included. A radiological and clinical assessment were performed the day before the operation and at 12 months post-operatively. Full-length standing anteroposterior radiographs were used to measure HKA and LLC. FFD and Hospital for Special Surgery (HSS) score were measured in the outpatient department. RESULTS: The incidence of lengthening was 92.0% and the mean LLC was 18.85mm (SD, 19.60mm). Postoperative LLD over 10mm occurred in 26% and the mean of postoperative LLD was 4.21mm (SD, 7.96mm). The LLC was correlated with postoperative LLD (rs=0.357, p=0.011) and the HKA change (rs=0.375, p=0.007), but not with the FFD improvement (rs=0.164, p=0.255) and HSS improvement (rs=0.076, p=0.613) or postoperative HSS (rs=0.094, p=0.528). CONCLUSION: LLC was affected by HKA improvement but not by FFD improvement after TKA for patients with valgus deformity. Additionally, LLC did not affect the clinical score. LEVEL OF EVIDENCE: III; retrospective cohort study.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Luxaciones Articulares , Osteoartritis de la Rodilla , Humanos , Articulación de la Rodilla/cirugía , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/cirugía , Estudios Retrospectivos , Rodilla/cirugía , Luxaciones Articulares/cirugía
13.
Am J Sports Med ; 52(2): 368-373, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38186334

RESUMEN

BACKGROUND: Graft tears are common postoperative findings in meniscal allograft transplant (MAT). Graft tear in medial MAT may be different from that of lateral MAT, considering the difference between medial meniscal tears and lateral meniscal tears. Moreover, medial MAT is frequently accompanied by ligament reconstruction, which is associated with graft tear. The effect of graft tear on the long-term survivorship of medial MAT has not been investigated. HYPOTHESIS: Graft tear would adversely affect the survivorship of medial MAT and the effect would be different according to the timing of graft tear. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 55 patients undergoing medial MAT between June 2019 and March 2000 were retrospectively reviewed. Postoperative magnetic resonance imaging (MRI) scans were reviewed to identify graft tears, and the timing of their occurrence was investigated. Postoperative MRI was performed routinely during the first postoperative year and every 2 years thereafter. The patients were classified into a no graft tear (NT) group, early graft tear (occurring within 1 year; ET) group, and late graft tear (occurring 1 year after surgery; LT) group. The survival rate of medial MAT was estimated according to graft tear, with a failure being defined as (1) reoperations including arthroplasty, realignment osteotomy, revision MAT, and meniscectomy (>50% of the graft or to the zone of the meniscocapsular junction) or (2) Lysholm score <65. Clinical scores were compared between the groups. RESULTS: The mean follow-up duration was 8.6 ± 5.3 years. During that period, clinical failures occurred in 6 (10.9%) patients. The overall survival rate at 5 years was 94.0% (95% CI, 90.6%-97.4%). Graft tears were seen in 18 patients: 6 patients in the ET group and 12 patients in the LT group. The median time when the graft tear was noted on MRI scans was 5.5 months (range, 1-11 months) postoperatively in the ET group and 99.5 months (range, 19-264 months) postoperatively in the LT group. Five patients in the ET group had root tears, whereas 9 patients in the LT group had complex or horizontal tears. The 5-year survival rate of the ET group was 62.5% (95% CI, 41.2%-83.8%), which was significantly lower than that of the NT group (96.8%; 95% CI, 93.6%-99.9%) and the LT group (85.7%; 95% CI, 72.5%-98.9%; P = .002). The mean postoperative Lysholm scores were 85.6 ± 17.9 in the NT group, 93.0 ± 2.8 in the ET group, and 79.3 ± 11.6 in the LT group, showing no significant difference between the groups (Kruskal-Wallis test, P = .058). CONCLUSION: Clinical relevance of graft tear that occurred after medial MAT was dependent upon its timing. ET was a risk factor for clinical failure, whereas LT did not adversely affect graft survivorship. Lysholm scores did not differ according to graft tear.


Asunto(s)
Laceraciones , Meniscos Tibiales , Humanos , Estudios de Cohortes , Estudios Retrospectivos , Meniscos Tibiales/cirugía , Meniscos Tibiales/trasplante , Factores de Riesgo , Aloinjertos , Estudios de Seguimiento
14.
Bone Joint J ; 106-B(5): 460-467, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38688498

RESUMEN

Aims: The aim of this study was to investigate the distribution of phenotypes in Asian patients with end-stage osteoarthritis (OA) and assess whether the phenotype affected the clinical outcome and survival of mechanically aligned total knee arthroplasty (TKA). We also compared the survival of the group in which the phenotype unintentionally remained unchanged with those in which it was corrected to neutral. Methods: The study involved 945 TKAs, which were performed in 641 patients with primary OA, between January 2000 and January 2009. These were classified into 12 phenotypes based on the combined assessment of four categories of the arithmetic hip-knee-ankle angle and three categories of actual joint line obliquity. The rates of survival were analyzed using Kaplan-Meier methods and the log-rank test. The Hospital for Special Surgery score and survival of each phenotype were compared with those of the reference phenotype with neutral alignment and a parallel joint line. We also compared long-term survival between the unchanged phenotype group and the corrected to neutral alignment-parallel joint line group in patients with Type IV-b (mild to moderate varus alignment-parallel joint line) phenotype. Results: The most common phenotype was Type I-b (mild to moderate varus alignment-medial joint line; 27.1% (n = 256)), followed by Type IV-b (23.2%; n = 219). There was no significant difference in the clinical outcomes and long-term survival between the groups. In Type IV-b phenotypes, the neutrally corrected group showed higher 15-year survival compared with the unchanged-phenotype group (94.9% (95% confidence interval (CI) 92.0 to 97.8) vs 74.2% (95% CI 98.0 to 100); p = 0.020). Conclusion: Constitutional varus was confirmed in more than half of these patients. Mechanically aligned TKA can achieve consistent clinical outcomes and long-term survival, regardless of the patient's phenotype. The neutrally corrected group had better long-term survival compared with the unchanged phenotype group.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Pueblo Asiatico , Osteoartritis de la Rodilla , Fenotipo , Humanos , Artroplastia de Reemplazo de Rodilla/métodos , Osteoartritis de la Rodilla/cirugía , Masculino , Femenino , Anciano , Persona de Mediana Edad , Resultado del Tratamiento , Estudios Retrospectivos , Anciano de 80 o más Años , Falla de Prótesis , Estimación de Kaplan-Meier
15.
Medicine (Baltimore) ; 103(16): e37781, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38640326

RESUMEN

Several studies have revealed the risk factors for carpal tunnel syndrome (CTS). However, no studies have evaluated the influence of these risk factors on the selection of treatment modalities for CTS. This study aimed to determine the influence of CTS risk factors on the selection of CTS treatment modalities with a focus on corticosteroid injection (CI) and surgery. We conducted a retrospective cohort study of patients aged ≥20 years with newly diagnosed CTS in the Korean health insurance review and assessment service between 2010 and 2019. We evaluated the demographic information, the existence of CTS risk factors, and the applied treatment modalities for CTS, including CI and operation. The CTS risk factors include age, sex, diabetes mellitus, osteoarthritis of the hand or wrist, rheumatoid arthritis, hypothyroidism, gout, chronic kidney disease (CKD) on dialysis, antiestrogen or aromatase inhibitor medication, and a history of distal radius fracture (DRF). Multivariable logistic regression analyses were conducted. Age over 80 years was the most significantly associated factor for the selection of CI in CTS (odd ratio [OR], 2.149; 95% confidence interval [CI], 2.092 to 2.209; P < .001). Among underlying diseases or medications, CKD on dialysis (OR, 4.001; 95% CI, 3.819-4.193; P < .001) was the most significant associated factor for the selection of operation for CTS, followed by a history of DRF (OR, 1.803; 95% CI, 1.749-1.860; P < .001). Old age was the most significantly related factor for selecting CI. Among underlying diseases or medications, CKD on dialysis and the history of DRF were the most significantly related factors for selecting operative treatment. For these patients, clinicians should proactively consider an operation to reduce the long-term discomfort and economic burdens.


Asunto(s)
Síndrome del Túnel Carpiano , Insuficiencia Renal Crónica , Humanos , Síndrome del Túnel Carpiano/epidemiología , Síndrome del Túnel Carpiano/etiología , Síndrome del Túnel Carpiano/cirugía , Estudios Retrospectivos , Diálisis Renal/efectos adversos , Factores de Riesgo , Corticoesteroides/uso terapéutico , Insuficiencia Renal Crónica/complicaciones
16.
Polymers (Basel) ; 16(5)2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38475280

RESUMEN

We report chemically tunable n-type titanium oxides using ethanolamine as a nitrogen dopant source. As the amount of ethanolamine added to the titanium oxide precursor during synthesis increases, the Fermi level of the resulting titanium oxides (ethanolamine-incorporated titanium oxides) significantly changes from -4.9 eV to -4.3 eV, and their free charge carrier densities are enhanced by two orders of magnitudes, reaching up to 5 × 1018 cm-3. Unexpectedly, a basic ethanolamine reinforces not only the n-type properties of titanium oxides, but also their basicity, which facilitates acid-base ionic junctions in contact with acidic materials. The enhanced charge carrier density and basicity of the chemically tuned titanium oxides enable multi-junction solar cells to have interconnecting junctions consisting of basic n-type titanium oxides and acidic p-type PEDOT:PSS to gain high open-circuit voltages of 1.44 V and 2.25 V from tandem and triple architectures, respectively.

17.
Heliyon ; 10(9): e30563, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38742076

RESUMEN

Farmers cultivate plants in the winter using water curtain cultivation (WCC) facilities by spraying groundwater to keep them warm. In this study, the WCC facilities exhibited high radon concentrations during winter. The risk varied significantly depending on the facility operation, peaking in the early morning and then decreasing upon ventilation. At all measurement sites, radon concentrations were low when groundwater was not used. Even during the period of facility groundwater use, if water vapor condensation does not occur, there is no significant difference from soil-only emissions. However, once water vapor condensation occurs, radon accumulates rapidly, depending on the degree of radon contamination in the groundwater. Because groundwater contamination varies according to dilution by regional rainfall or inflow from other regions due to groundwater movement, abnormal changes in radon content occur. We found that in the absence of water vapor condensation in the facility, all the radon emitted from the soil and groundwater quickly escaped to the atmosphere, resulting in significantly lower indoor radon concentrations. These findings pave the way for the development of new methods to mitigate radon in WCC facilities.

18.
Eur Radiol ; 23(3): 786-96, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23011213

RESUMEN

OBJECTIVES: To evaluate the clinical efficacy and safety of self-expandable metallic stent (SEMS) placement for malignant oesophageal strictures and their relationship with stent designs. METHODS: Seven generations of SEMS were used to treat 645 consecutive patients with oesophageal strictures. Logistic regression models were constructed to identify predictive factors associated with complications. RESULTS: Stent placement was technically successful in 641 of 645 patients (99.4%). The clinical success rate was 95.5%. There were 260 (40.3%) complications after stent placement. Due to complications, 68 stents were removed; 66 of 68 stents (97.1%) were removed successfully. Stainless steel (SS) stents (odds ratio [OR] 4.18; 95% confidence interval [CI] 2.10, 8.32) and radiation therapy (RT) before stent placement (OR 4.23; CI 2.02, 8.83) were significantly associated with severe pain. Flared ends (OR 9.63; CI 3.38, 27.43), stricture length <6 cm (OR 2.01; CI 1.13, 3.60), and a stent diameter <18 mm (OR 3.00; CI 1.32, 6.84) were predictive factors of stent migration. Polyurethane membranes were associated with more frequent tumour ingrowth than polytetrafluoroethylene (PTFE) membranes (P = 0.002). CONCLUSIONS: Despite the relatively high complication rate, retrievable self-expandable PTFE-covered nitinol stents equipped with a head and a tail appeared to be an effective treatment for malignant oesophageal strictures.


Asunto(s)
Neoplasias Esofágicas/epidemiología , Neoplasias Esofágicas/cirugía , Estenosis Esofágica/epidemiología , Estenosis Esofágica/cirugía , Complicaciones Posoperatorias/epidemiología , Stents/estadística & datos numéricos , Causalidad , Remoción de Dispositivos/estadística & datos numéricos , Femenino , Humanos , Masculino , Metales , Persona de Mediana Edad , Prevalencia , Diseño de Prótesis , República de Corea/epidemiología , Resultado del Tratamiento
19.
AJR Am J Roentgenol ; 201(1): 202-7, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23789676

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate the clinical features of patients with gastric conduit strictures after esophagectomy and to report our initial experience in the management of these strictures with fluoroscopically guided balloon dilation, temporary stent placement, or both. MATERIALS AND METHODS: From January 1996 to January 2012, 12 patients with gastric conduit stricture after esophagectomy underwent fluoroscopic balloon dilation, temporary stent placement, or both. Stent placement was indicated in patients who had gastro-respiratory fistulas or recurrent symptoms within 2 weeks of balloon dilation. Technical and clinical success, complications, and length of strictures were retrospectively evaluated. RESULTS: The mean length of strictures in all patients was 49 mm (range, 21-76 mm). The strictures were accompanied by gastrorespiratory fistulas in four patients. Seven patients with gastric conduit strictures without fistulas underwent 23 balloon dilations. Five patients underwent stent placement owing to gastrorespiratory fistula formation (n = 4) and frequent recurrent symptoms after balloon dilation (n = 1). During a mean follow-up period of 8 months (range, 2-28 months), clinical success was achieved in 11 patients (91.6%) after a single balloon dilation (n = 1), multiple balloon dilations (n = 5), or stent placement (n = 5). Complications occurred in 3 of 10 patients (30%) after balloon dilation and in one of five patients (20%) after stent placement. CONCLUSION: Gastric conduit strictures are characterized by their substantial length and tend to be accompanied by gastrorespiratory fistulas. Despite relatively high complication and recurrence rates, this study may offer a viable treatment of gastric conduit strictures by using fluoroscopically guided balloon dilation and stent placement.


Asunto(s)
Dilatación/métodos , Estenosis Esofágica/terapia , Esofagectomía , Gastrostomía , Complicaciones Posoperatorias/terapia , Stents , Anciano , Estenosis Esofágica/diagnóstico por imagen , Estenosis Esofágica/etiología , Femenino , Fluoroscopía , Humanos , Masculino , Persona de Mediana Edad , Radiografía Intervencional , Estudios Retrospectivos , Resultado del Tratamiento
20.
Am J Sports Med ; 51(14): 3701-3705, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37975518

RESUMEN

BACKGROUND: Graft tears are often observed on magnetic resonance imaging after lateral meniscal allograft transplantation (MAT). Their characteristics, such as the location and configuration, are likely to be different depending on the timing of the injury. However, the clinical relevance of early and late graft tears has not been investigated. HYPOTHESIS: (1) Both early and late graft tears would be associated with the clinical failure of lateral MAT, and (2) an early graft tear (ET) would lead to worse outcomes than a late graft tear (LT) or an intact graft. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 261 patients who had undergone lateral MAT between March 2000 and June 2019 were retrospectively reviewed. The graft tear was investigated using magnetic resonance imaging, which was performed routinely during the first postoperative year and every 2 years thereafter. The patients were classified according to the timing of the graft tear: no graft tear (NT) group, ET (≤1 year after surgery) group, and LT (>1 year after surgery) group. Clinical failure was defined as (1) reoperations including arthroplasty, realignment osteotomy, revision MAT, and meniscectomy (>50% of the graft or to the zone of the meniscocapsular junction) or (2) a Lysholm score of <65. Risk factors for a low survival rate were investigated using Cox regression analysis. A comparison of the Lysholm scores for each group was also performed. RESULTS: There were 24 (9.2%) patients who had clinical failure at a mean follow-up of 7.5 ± 4.3 years. The overall survival rate at 5 years was 92.8% (95% CI, 91.1%-94.5%). A graft tear was noted in 80 patients: 23 patients in the ET group and 57 patients in the LT group. The most common tear pattern was a meniscocapsular tear in the ET group and a complex tear in the LT group. The hazard ratios for clinical failure in the ET and LT groups were 30.7 (95% CI, 9.4-76.4; P < .001) and 4.0 (95% CI, 1.3-12.9; P = .013), respectively. The Lysholm score of the ET group (82.7 ± 14.8) was significantly lower than that of the other 2 groups (NT: 87.6 ± 11.7; LT: 90.7 ± 9.0; P = .024). CONCLUSION: An ET was a major risk factor for the clinical failure of lateral MAT. An LT was associated with a lower survival rate. An ET was also associated with worse clinical outcomes.


Asunto(s)
Meniscos Tibiales , Humanos , Estudios de Cohortes , Estudios Retrospectivos , Meniscos Tibiales/cirugía , Meniscos Tibiales/trasplante , Trasplante Homólogo/efectos adversos , Aloinjertos , Estudios de Seguimiento
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