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61.
Background We have previously shown promising activity of hepatic arterial infusion (HAI) oxaliplatin combined with intravenous (IV) 5-fluorouracil (5-FU) and leucovorin (LV) as first-line chemotherapy in patients with colorectal liver metastases (CRLM) (intent-to-treat [ITT] objective response rate [ORR], 64%; secondary resection rate, 18%; overall survival [OS], 27 months). Whether this regimen could be beneficial after systemic chemotherapy failure is unknown. Methods Patients with unresectable CRLM and history of systemic chemotherapy failure were treated bimonthly with HAI oxaliplatin (100 mg/m2 2 hours) combined with IV LV and IV bolus and infusional 5FU (modified LV5FU2 regimen). Results Forty-four consecutive patients (median age 56 years; median number of prior systemic chemotherapy regimens, 2 range 1–5) were included, of whom 43 (98%) had previously received oxaliplatin (n = 34), irinotecan (n = 37), or both (n = 28). Patients received a median of nine cycles of HAI oxaliplatin and IV modified LV5FU2 (range 0–25). Toxicity included grade 3–4 neutropenia (43%), grade 2–3 neuropathy (43%), and grade 3–4 abdominal pain (14%). We observed 24 partial ORs (62%) among the 39 assessable patients (ITT ORR, 55%; 95% CI, 40–69%), including 17, 12, and 12 patients who had failed to respond to prior systemic chemotherapy with FOLFIRI, FOLFOX, or both, respectively. Tumor response allowed further R0 surgical resection (n = 7) or radiofrequency ablation (n = 1) of initially unresectable CRLM in eight patients (18%). Median progression-free survival and OS were 7 and 16 months, respectively. Conclusions HAI oxaliplatin and IV LV5FU2 is feasible, safe, and shows promising activity after systemic chemotherapy failure, allowing surgical resection of initially unresectable CRLM in 18% of patients.  相似文献   
62.
Lung hamartomas are rare benign tumors of the bronchi. Their management consists of bronchoscopic excision or removal through a thoracotomy and bronchotomy whenever there is a large tumor totally obstructing the bronchial lumen. As a lung-sparing procedure is usually the aim, various bronchoplastic techniques have been described, providing a functional lumen of the repaired bronchus. We describe a simple technique that can be safely undertaken to preserve a satisfactory diameter of the bronchus or trachea and prevent a stenosis at the site of repair.  相似文献   
63.
OBJECTIVE: To evaluate the radiographic and clinical outcome, including the incidence of recurrence, in patients with displaced greater tuberosity (GT) fractures associated with a traumatic anterior shoulder dislocation. DESIGN: Retrospective study. SETTING: University Hospital (Level 1 trauma center). PATIENTS: There were 34 completely evaluated patients (19 male, 15 female) seen between 1993 and 2002 with a displaced GT fracture associated with a traumatic anterior shoulder dislocation. Average age was 52.8 years and the mean follow-up period was 4.8 years (range, 2.0 to 10 years). INTERVENTION: All GT fractures were internally fixed solely with heavy non-absorbable sutures and any associate rotator cuff tear was repaired at the same time. A special rehabilitation protocol was administered in all patients. MAIN OUTCOME MEASUREMENTS: Functional assessment was obtained using the parameters of the Constant score which grades outcomes as excellent, very good, good and poor. RESULTS: Overall, there were 25 (73.5%) excellent, 6 (17.6%) very good, 2 (5.8%) good and 1 (3.1%) poor results, and the average Constant score was 88.4 (range 45.0 to 100.0). All fractures healed radiographically, without evidence of secondary displacement, except in one patient. No case of recurrence of dislocation was noted in any patient. Partial absorption or "lysis" of the GT without significant clinical relevance was detected in 4 cases. CONCLUSIONS: Displaced fractures of the GT after traumatic anterior shoulder dislocation may result in limitation of motion and functional disability if they are not treated promptly by surgery. Open reduction and stable fixation of the GT along with rotator cuff repair when present, allows for early passive motion of the joint, and yields excellent final results in approximately three quarters of the patients and restores their ability to return to full activities of daily living. A compliant patient is also necessary for a successful result.  相似文献   
64.
BACKGROUND: Infected femoral artery pseudoaneurysm (IFAP) is a severe complication in parenteral drug abusers, with difficult and controversial management. Ligation alone without revascularization is frequently associated with later intermittent claudication and limb amputation. Furthermore, arterial reconstruction with a synthetic or venous conduit is limited because of a contaminated field and, often, unavailability of autologous venous grafts. In this study, we present our experience with the internal iliac artery (IIA) as a graft for arterial reconstruction after IFAP excision in these patients. METHODS: Data of 14 consecutive patients who presented with IFAP secondary to parenteral drug abuse from 2001 to 2005 were analyzed. Twelve patients (85.7%) were male. The median age was 27 years (range, 19-42 years). In 13 cases, the IFAP involved the common femoral artery, and in 1 case it involved the profunda femoris artery (PFA). In nine patients, we used the IIA for arterial reconstruction (five as a patch and four as an interposition graft), whereas in two patients the arterial deficit was repaired with a great saphenous vein patch. In two cases, an extra-anatomic bypass with a synthetic polytetrafluoroethylene graft was performed. In one patient, the pseudoaneurysm involved the PFA and was treated with excision and ligation of the PFA. RESULTS: All nine patients who underwent revascularization with the use of IIA were free of claudication symptoms. None of them experienced any perioperative complications, had signs of reinfection, or required limb amputation during the follow-up period (median, 19 months; range, 4-52 months). Regarding the remaining five patients, one died 25 days after surgery because of multiorgan failure, and one underwent reoperation because of proximal anastomotic rupture of a synthetic graft. The latter patient finally underwent a transmetatarsal amputation. CONCLUSIONS: The use of IIA for arterial reconstruction after IFAP excision in drug abusers is safe and effective. These preliminary results indicate that the implementation of this technique offers many advantages compared with traditional treatment options.  相似文献   
65.
OBJECT: The authors' aim was to assess the ability of apparent diffusion coefficient (ADC) ratios in distinguishing brain abscesses from cystic or necrotic neoplasms. METHODS: Fifty-three patients with rim-enhancing masses in the brain observed on T1-weighted MR images were included: 26 had abscesses (14 bacterial, six nonbacterial, and six of unknown origin), 11 had glioblastoma multiforme, and 16 had rim-enhancing metastasis. The ADC values, derived from diffusion-weighted imaging, were measured in the most homogeneous portion of the cystic component of the mass. The ADC ratios were calculated by dividing the ADC values from the nonenhancing cystic portion of the mass by the ADC values from contralateral normal-appearing white matter. Lesions were further differentiated based on presence, absence, or incompleteness of a T2 hypointensity rim. The mean (+/- standard deviation) ADC ratios were significantly higher in neoplasms than in abscesses (2.45 +/- 0.91 compared with 1.12 +/- 0:53, p < 0.01). The accuracy of ADC ratios in discriminating abscesses from neoplasms, determined by the area under the receiver operating characteristic curve (Az), was high: 0.91 +/- 0.04 (mean +/- standard error of the mean [SEM]). The threshold of 1.7 was associated with highest efficiency (87%) in discriminating abscesses from neoplasms. If only bacterial abscesses were analyzed compared with neoplasms, the Az increased to 0.96 +/- 0.03 (SEM). Using ADC ratios and T1 rim characteristics, 50 of 53 lesions were correctly classified (efficiency 94.3%). CONCLUSIONS: The accuracy of ADC ratios in discriminating brain abscesses from cystic or necrotic neoplasms is very high and can be further improved using T2 rim characteristics.  相似文献   
66.
67.

Background/Purpose

Living donor liver transplantation has become a cornerstone for the treatment of children with end-stage hepatic dysfunction, especially within populations or countries with low rates of organ utilization from deceased donors. The objective is to report our experience with 185 living donors operated on by a team pediatric surgeons in a tertiary center for pediatric liver transplantation.

Methods

Retrospective analysis of medical records of donors of hepatic grafts for transplant undergoing surgery between June 1998 and March 2013.

Results

Over the last 14 years, 185 liver transplants were performed in pediatric recipients of grafts from living donors. Among the donors, 166 left lateral segments (89.7%), 18 left lobes without the caudate lobe (9.7%) and 1 right lobe (0.5%) were harvested. The donor age ranged from 16 to 53 years, and the weight ranged from 47 to 106 kg. In 10 donors, an additional graft of the donor inferior mesenteric vein was harvested to substitute for a hypoplastic recipient portal vein. The transfusion of blood products was required in 15 donors (8.1%). The mean hospital stay was 5 days. No deaths occurred, but complications were identified in 23 patients (12.4%): 9 patients experienced abdominal pain and severe gastrointestinal symptoms and 3 patients required reoperations. Eight donors presented with minor bile leaks that were treated conservatively, and 3 patients developed extra-peritoneal infections (1 wound collection, 1 phlebitis and 1 pneumonia). Eight grafts (4.3%) showed primary dysfunction resulting in recipient death (3 cases of fulminant hepatitis, 1 patient with metabolic disease, 1 patient with Alagille syndrome and 3 cases of biliary atresia in infants under 1 year old). There was no relation between donor complications and primary graft dysfunction (P = 0.6).

Conclusions

Living donor transplantation is safe for the donor and presents a low morbidity. The donor surgery may be performed by a team of trained pediatric surgeons.  相似文献   
68.
The purpose of this study was to sequentially monitor anti‐HLA antibodies and correlate the results with antibody‐mediated rejection (AMR), graft survival (GS), and graft function (GF). We collected sera from 111 kidney transplant recipients on transplant days 0, 7, 14, 30, 60, 90, 180, and 360 and analyzed PRA levels by ELISA. DSAs were analyzed by single‐antigen beads in rejecting kidneys. At pre‐transplant, 79.3% of the patients were non‐sensitized (PRA = 0%) and 20.7% were sensitized (PRA > 1%). After transplant, patients were grouped by PRA profile: no anti‐HLA antibodies pre‐ or post‐transplant (group HLApre?/post?; n = 80); de novo anti‐HLA antibodies post‐transplant (group HLApre?/post+; n = 8); sensitized pre‐transplant/increased PRA post‐transplant (group HLApre+/post↑; n = 9); and sensitized pre‐transplant/decreased PRA post‐transplant (group HLApre+/post↓; n = 14). De novo anti‐HLA antibodies were detected at 7–180 d. In sensitized patients, PRA levels changed within the first 30 d post‐transplant. Incidence of AMR was higher in HLApre?/post+ and HLApre+/post↑ than in HLApre?/post?, and HLApre+/post↓ (p < 0.001) groups. One‐yr death‐censored GS was 36% in group HLApre+/post↑, compared with 98%, 88% and 100% in groups HLApre?/post?, HLApre?/post+, and HLApre+/post↓, respectively (p < 0.001). Excluding first‐year graft losses, GF and GS were similar among the groups. In conclusion, post‐transplant antibody monitoring can identify recipients at higher risk of AMR.  相似文献   
69.

Background

While convergent placement of pedicle screws in the axial plane is known to be more advantageous biomechanically, surgeons intuitively aim toward a parallel placement of screws in the sagittal plane. It is however not clear whether parallel placement of screws in the sagittal plane is biomechanically superior to a non-parallel construct. The hypothesis of this study is that sagittal non-parallel pedicle screws do not have an inferior initial pull-out strength compared to parallel placed screws.

Methods

The established lumbar calf spine model was used for determination of pull-out strength in parallel and non-parallel intersegmental pedicle screw constructs. Each of six lumbar calf spines (L1-L6) was divided into three levels: L1/L2, L3/L4 and L5/L6. Each segment was randomly instrumented with pedicle screws (6/45 mm) with either the standard technique of sagittal parallel or non-parallel screw placement, respectively, under fluoroscopic control. CT was used to verify the intrapedicular positioning of all screws. The maximum pull-out forces and type of failure were registered and compared between the groups.

Results

The pull-out forces were 5,394 N (range 4,221 N to 8,342 N) for the sagittal non-parallel screws and 5,263 N (range 3,589 N to 7,554 N) for the sagittal-parallel screws (p?=?0.838). Interlevel comparisons also showed no statistically significant differences between the groups with no relevant difference in failure mode.

Conclusion

Non-parallel pedicle screws in the sagittal plane have at least equal initial fixation strength compared to parallel pedicle screws in the setting of the here performed cadaveric calf spine experiments.  相似文献   
70.

Background Context

The concept of dynamic stabilization (DS) of the lumbar spine for treatment of degenerative instability has been introduced almost two decades ago. Dynamic stabilization follows the principle of controlling movement in the coronal plane by providing load transfer of the spinal segment without fusion and, at the same time, reducing side effects such as adjacent segment disease (ASD). So far, only little is known about revision rates after DS due to ASD and screw loosening (SL).

Purpose

The present study aimed to evaluate the longitudinal revision rates following dynamic pedicle screw stabilization in the lumbar spine and to determine specific risk factors predictive for ASD, SL, and overall reoperation in a large cohort with considerable follow-up.

Design

We carried out a post hoc analysis of a prospectively collected database in a level I spine center.

Patients Example

The patient sample comprised 283 (151 female/132 male) consecutive patients suffering from painful degenerative lumbar segmental instability with or without spinal stenosis who underwent DS of the lumbar spine (Ulrich Cosmic, Ulrich Medical, Ulm, Germany) between January 2008 and December 2011.

Outcome Measures

Longitudinal reoperation rate and risk factors predictive for revision surgery were evaluated.

Methods

We analyzed the longitudinal reoperation rate due to ASD and SL and overall reoperation. Risk factors such as age, gender, body mass index, lumbar lordosis (LL), number of segments, and number of previous surgeries were taken into account. Regular and mixed model logistic regressions were performed to determine risk factors for revision surgery on a patient and on a screw level.

Results

The mean age was 65.7±10.2 years (range 31–88). One hundred thirty-two patients were stabilized in 1 segment, 134 in 2 segments, 15 in 3 segments, and 2 patients in 4 segments. Reoperation rate for ASD and SL after 1 year was 7.4 %, after 2 years was 15.0%, and after a mean follow-up of 51.4±15 months was 22.6%. Reasons for revision were SL in 19 cases (6.6%), ASD in 39 cases (13.7%), SL and ASD in 6 cases, hematoma in 2 cases (0.7%), cerebrospinal fluid fistulae in 3 cases (1.1%), infection in 6 cases (2.1%), and implant failure in 1 case (0.4%). The patients' age, the number of stabilized segments, and the number of previous surgeries and postoperative LL had a significant influence on the probability for revision surgery.

Conclusions

Reoperation rates after DS of the lumbar spine are comparable with rigid fixations. The younger the patient and the more segments are involved, the lower the LL and the more previous surgeries were found, the higher was the risk of revision. Risk of revision was almost twice as high in men compared with women. We therefore conclude that for clear clinical indication and careful evaluation of preoperative imaging data, DS using the Cosmic system seems to be a possible option. The presented data will help to further tailor indication and patient selection.  相似文献   
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