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71.
OBJECTIVE: Given the limited availability of small-sized cryopreserved pulmonary homografts, we implanted a series of Shelhigh No-React porcine pulmonic valve conduits (SPVC). The aim of this study was to evaluate the short-term performance following implantation. METHODS: From February 2000 to September 2000, the SPVC was implanted 25 times in 24 patients in the right ventricular outflow tract (RVOT) to correct congenital anomalies. The anatomical malformations were TOF/PA in eight patients, TGA/VSD/PS in four, truncus arteriosus in four, IAA/VSD/AS or AA in four, l-TGA/VSD in two and other in two. Age at operation was 2.8+/-3.9 years (mean+/-SD), including 12 patients under 1 year. The median conduit size was 14mm (range, 10-18). RESULTS: At a mean follow-up of 23+/-5 months, two late deaths (8%) have occurred. Although they were not primarily conduit related, both showed severe conduit stenosis. Twenty-one conduits (84%) showed mild to severe conduit stenosis, regurgitation or both. Two patients underwent balloon dilatation for distal conduit stenosis. Twelve conduits (48%) in 11 patients were removed at a median of 12 months (range, 2-18 months) due to RVOT obstruction in 11 and free conduit insufficiency with pseudoaneurysm in one. The typical findings of the explanted conduits were prominent intimal peel formation at the distal anastomosis without calcification. The actuarial freedom from reintervention at 18 months was 48+/-10%. CONCLUSIONS: Our experience of the SPVC with the diameter of 14mm or less has revealed a high incidence of distal conduit stenosis due to intimal peel formation resulting in early conduit failure. These findings have led us to abandon its use when other options are available.  相似文献   
72.
73.
Revision chronic ear surgery.   总被引:6,自引:0,他引:6  
OBJECTIVE: To report results of revision chronic ear surgery following guidelines of the American Academy of Otolaryngology-Head and Neck Surgery and to establish expectations for infection and cholesteatoma control and hearing outcomes. STUDY DESIGN: Retrospective case review of all patients who underwent revision chronic ear surgery from January 1, 1990 to December 31, 2000. Revision chronic ear surgery included canal wall up and canal wall down procedures with ossicular chain reconstruction performed as needed. Cholesteatoma control, hearing improvement, and closure of middle ear space are main outcome measures. SETTING: Tertiary referral center. RESULTS: Cholesteatoma recurrence rate was 57% at 1 year after surgery and 14% in patients with a minimum of a 5-year follow-up. Disease control was achieved in 96% of patients. Hearing was significantly improved in all surgical groups. Closure of the air-bone gap for revision partial ossicular replacement prosthesis cases (PORP) to less than 20 dB occurred in 50% of patients. Closure of the air-bone gap to within 30 dB for revision total ossicular replacement prosthesis (TORP) occurred in 60% of patients. Canal wall down status had a significant impact on hearing results after PORPs and TORPs; patients with intact canal walls had significantly better hearing results. Diagnosis of cholesteatoma significantly impacted hearing results for TORPs but not PORPS. CONCLUSIONS: Cholesteatoma control rates after revision surgery are similar to primary cases. Significant improvement in hearing can be expected after revision chronic ear surgery. Hearing results after a revision surgery that requires a PORP is worse than primary cases and is canal wall status dependent. Closure of the middle ear space and creation of a safe dry ear can be expected after revision chronic ear surgery. SIGNIFICANCE: This is a review of a large series of exclusively revision chronic ear surgery. EBM rating: C-4.  相似文献   
74.
75.
PURPOSE: In this study, we examined the use of a 2.0-mm locking bone plate/screw system in mandibular surgery. PATIENTS AND METHODS: All patients who were treated with a 2.0-mm locking bone plate/screw system during an 8-month period for fractures of the mandible or other defects of the mandible were prospectively studied. Ease of use of locking plate/screw system, characteristics of the fractures and defects, and complications were tabulated. RESULTS: A total of 80 fractures in 59 patients were treated with the 2.0-mm locking plate/screw system. One hundred two 2.0-mm locking plates were applied to the 80 fractures; 58 fractures received 1 plate and 22 fractures received 2 plates. There were no intraoperative difficulties associated with their application. Fracture reductions were considered to be excellent in all cases. At the latest follow-up, all fractures had healed, but 2 patients had slight malocclusions. Six patients developed postsurgical infections. Only 1 patient required hospitalization for treatment of the infection; all others were managed in the outpatient clinic. Four patients required removal of their plates for varying reasons. CONCLUSIONS: The use of a 2.0-mm locking plate/screw system was found to be simple and to provide sound fixation in all cases.  相似文献   
76.
Nine patients have undergone single-stage radical cystectomy and ileal conduit urinary diversion two to fifty-one months after coronary artery bypass procedures. Two patients presenting with intractable angina at the time their malignant disease was being evaluated required bypass surgery before cystectomy could be undertaken. No significant cardiac morbidity occurred postoperatively, and all remain alive without evidence of malignant disease.  相似文献   
77.
PURPOSE: We sought to report the outcome of secondary intraocular lens (IOL) implantation in children. METHODS: This was a retrospective case review. RESULTS: A total of 77 eyes were identified. An average age at secondary implantation was 7.8 +/- 5.0 years, whereas the average age at primary cataract surgery was 1.5 +/- 2.6 years. Average follow-up was 2.7 +/- 1.9 years. Thirty eyes received a hydrophobic acrylic IOL implantation whereas 47 eyes received a PMMA IOL. The sites of fixation for implanted IOLs were as follows: anterior-chamber (n = 6), sulcus (n = 42), in-the-bag (n = 14), optic-capture (n = 6), piggyback (n = 4), and sutured (n = 5). Complications included clinically significant decentration, 4 (5.2%); visual axis opacification, 4 (5.2%); dislocation of the IOL, 2 (2.6%); and pupillary capture requiring repositioning of IOL, 1 (1.3%). Clinically significant decentration requiring surgical intervention was noted only in eyes with sulcus-fixated foldable IOLs (28.6%; 4/14). None of the 29 eyes with sulcus-fixated PMMA IOL implantation developed decentration. All the decentrations were in an inferior direction and occurred in eyes of male patients (P = 0.03). Eyes with an axial length of >23 mm were 4 times more likely to develop decentration if implanted with a sulcus-fixated foldable IOL when compared with eyes measuring <23 mm (P = 0.03). Postoperative geometric mean visual acuity was significantly better than preoperative visual acuity (P < 0.001). CONCLUSION: Secondary IOL implantation can be safely achieved in pediatric eyes. In-the-bag fixation of foldable IOLs is associated with a low rate of complications. Foldable lenses appear to have a higher rate of decentration than PMMA lenses when placed in the sulcus in eyes of myopic male patients.  相似文献   
78.
Nine infants, who presented with renal failure within the first 3 months of life, were treated with continuous ambulatory peritoneal dialysis (CAPD). Seven infants survived to an age of 12–15 months, when they received transplants. Two patients died while on CAPD. Six infants are alive with a functioning renal allograft, at an average age of 35.5 months and an average of 22 months post-transplant. Neurological development is normal in four of the six infants tested. The mean current height of the six transplant recipients is just below 2 SD from the mean.  相似文献   
79.
Eighty patients who had undergone jejunoileal bypass for morbid obesity were examined by ultrasound at their routine follow-up visits to the clinic. Ultrasonographic evidence of intestinal intussusception was found in 15 patients (19%). Two of these patients were asymptomatic. Ultrasonographic findings were confirmed by operation in 6 patients (5 with intussusception, 1 negative).  相似文献   
80.
PURPOSE: This study investigated the agreement and repeatability of five techniques of measuring tear meniscus height (TMH). METHODS: Pairs of TMH measurements were obtained from one eye of 25 normal subjects with five techniques: optical coherence tomography in cross-section (OCT) and optical pachymetry in cross-section (PACH), without fluorescein; and 5 minutes after the instillation of fluorescein, optical pachymetry en-face (SL-F) and in cross-section (SL-X), and video capture en-face (VC). These 10 measurements were taken on different days within a period of 21 days. Additionally, immediately successive replicates were taken at the first visit when VC was used, allowing for the separation of technique repeatability from true day-to-day variation in TMH. RESULTS: Ninety-five percent confidence intervals for the mean TMH and 95% repeatability coefficients for repeated testing on separate occasions were: 0.25 to 0.29 mm, 0.14 mm--OCT, 0.30 to 0.36 mm, 0.13 mm--PACH, 0.27 to 0.34 mm, 0.092 mm--SL-F, 0.35 to 0.41 mm, 0.19 mm--SL-X, and 0.30 to 0.38 mm, 0.088 mm--VC. Reported repeatability coefficients are averages because, despite a relatively narrow experimental range, the measurements of low TMH were generally more repeatable than those of large TMH. Ninety-five percent limits of agreement were wide for all pairwise comparisons and included zero, indicating that the methods used in this study are interchangeable when taking single recordings, at least on subjects without dry eye. CONCLUSIONS: The average TMH of the five techniques was similar, although OCT and SL-X tended to record lower and higher values, respectively. However, their agreement for single recordings was poor, an inevitable consequence of the low intertest repeatability found for all methods. A much improved repeatability for immediate replicates indicated that this, in turn, was principally caused by a large day-to-day variation in TMH rather than measurement error.  相似文献   
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