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1.
M Panjehpour B F Overholt R C DeNovo R E Sneed M G Petersen 《Lasers in surgery and medicine》1992,12(6):631-638
A cylindrical balloon was developed to improve delivery of circumferential light for photodynamic therapy (PDT) of esophageal carcinoma. The balloon consisted of a 36-mm-long clear cylindrical membrane and a central tube to hold a cylindrical diffuser in the center of the lumen. Three isotropic probes were placed on the outside of the balloon to allow measurement of delivered light dose to the esophageal mucosa. The balloon was tested in the normal esophagus of 8 dogs that were injected with 4.0 mg/kg of PHOTOFRINR. Endoscopy was performed 48 hours following the injection, and under endoscopic observation the balloon assembly was passed, fixed in place, and inflated. A 1-cm cylindrical diffuser was passed into the central tube and 150, 300, and 600 Joules/cm of 630 nm laser light was delivered at 25 cm, 15 cm, and 5 cm proximal to the gastroesophageal junction. One control dog was illuminated using the cylindrical diffuser alone at doses of 300 and 600 Joules/cm of diffuser. Complete circumferential tissue response was obtained when the balloon was used. Relatively uniform light intensities were measured around the lumen. In contrast, noncircumferential and unpredictable PDT responses were generated when the cylindrical diffuser was used without the balloon. 相似文献
2.
Bergein F. Overholt Masoud Panjehpour Robert C. Denovo Mark G. Petersen 《Lasers in surgery and medicine》1994,14(1):27-33
Although delivery of uniform circumferential light is desirable during photodynamic therapy of advanced esophageal cancer in humans, early esophageal cancer may need only targeted treatment. Studies were performed in the canine esophagus of eight animals to investigate whether use of a “windowed” (shaded) centering balloon would improve targeted illumination of esophageal mucosa for photodynamic therapy. Shaded balloons were developed with a 2-cm-long, 360° or 180° clear “window.” Photofrin 4 mg/Kg was used as the photosensitizer. Light at 630 nm was delivered at 300 J/cm or 600 J/cm. Isotropic probes placed on the balloon wall allowed real-time measurement and verification of relatively uniform light doses delivered to esophageal mucosa during balloon photodynamic therapy. With the windowed balloon, targeted delivery of photodynamic therapy was possible. Using the 180° balloon, mucosa exposed to illumination was destroyed, whereas mucosa protected from light by the balloon shading was undamaged. Healing was complete and strictures did not occur. The shading of the balloon protected normal mucosa and prevents the formation of esophageal strictures. The “windowed” centering balloon provides a technology and technique that allows targeted delivery of uniform light during esophageal PDT. © 1994 Wiley-Liss, Inc. 相似文献
3.
P Topart C Deschamps R Taillefer A Duranceau 《The Annals of thoracic surgery》1992,54(6):1046-51; discussion 1051-2
From 1978 to 1983, 17 patients had an esophagocardiomyotomy with an added short total fundoplication as an antireflux procedure. Thirteen had achalasia and 4, diffuse esophageal spasm. All patients initially had the usual symptoms of these motor disorders. Early after the operation all became asymptomatic, but over the years of follow-up, symptoms reappeared in 14 of 17 patients, and 5 required reoperation. The distal esophageal transverse diameter showed progressive dilatation from 3.9 cm preoperatively to more than 6 cm after 10 years of evolution. Over the same period, deterioration in the esophageal emptying capacity caused esophageal stasis to increase from 32% to 75%. Manometric changes were significant after the operation: resting pressures in the esophageal body decreased from 10.5 to 4.4 mm Hg (p < 0.001) proximally and from 12.2 to 4.6 mm Hg distally (p < 0.001). Peak contraction pressures became significantly weaker: 38 to 30 mm Hg in the proximal esophagus (p < 0.001) and from 49.2 to 28.1 in the distal esophagus (p < 0.001). Tertiary contractions were unchanged distally, but peristalsis reappeared in more than 30% of all swallows in the proximal half of the esophageal body. The resting pressure gradient in the lower esophageal sphincter area was reduced from 25.5 to 7.4 mm Hg by the operation. This gradient remained stable over 10 years of follow-up. No significant acid exposure was documented in 8 patients undergoing 24-hour pH recordings after their operation. Endoscopy revealed dilatation and retention without evidence of reflux esophagitis damage. Total fundoplication when associated with esophageal myotomy results in improved symptoms in the early postoperative phase.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
van den Boogert J van Staveren HJ de Bruin RW Eikelaar JH Siersema PD van Hillegersberg R 《The Annals of thoracic surgery》1999,68(5):1763-1769
BACKGROUND: Photodynamic therapy with 5-aminolevulinic acid-induced photosensitization could selectively eliminate esophageal epithelial lesions. This study aimed at optimizing laser parameters for 5-aminolevulinic acid photodynamic therapy of the normal rat esophagus. METHODS: Sixty rats received 200 mg/kg 5-aminolevulinic acid orally and were illuminated 3 hours later with either 633 or 532 nm light (n = 30 for each group) through an endoesophageal balloon catheter. Rats received either 8.3 or 25 J/cm diffuser, applied with a 33, 100, or 300 mW/cm diffuser. During illumination, tissue fluorescence measurements and light dosimetry were done. Rats were sacrificed at 48 hours after photodynamic therapy. RESULTS: During illumination, protoporphyrin IX fluorescence declined faster when a higher power output was used. Fluence rate at the esophageal surface was highest for 633-nm light. At 532 nm, light caused less damage to the epithelium and muscle than 633-nm light. Illumination with 33 mW resulted in selective epithelial ablation, whereas illumination with 300 mW caused muscle damage with minor epithelial damage. CONCLUSIONS: The assumed selective epithelial damage of 5-aminolevulinic acid photodynamic therapy in the esophagus largely depends on the combination of wavelength, power, and light dose applied. Most selective epithelial damage was found when low-power 633-nm light was used. 相似文献
5.
Panjehpour M DeNovo RC Petersen MG Overholt BF Bower R Rubinchik V Kelly B 《Lasers in surgery and medicine》2002,30(1):26-30
BACKGROUND AND OBJECTIVE: Verteporfin is a new photosensitizer with short-term skin photosensitivity. The objective of this preclinical study was to find the light dose that effectively ablates canine esophageal mucosa when delivered 30 minutes after Verteporfin injection. STUDY DESIGN/MATERIALS AND METHODS: Verteporfin was administered intravenously (0.75 mg/kg). 630 nm light from KTP/Dye laser was delivered using an esophageal Photodynamic therapy (PDT) balloon. In Phase I study, animals were treated 30 minutes after drug injection using 40, 60, and 80 J/cm to find the desired light dose. Using results from phase I and application of reciprocity principle (light dose vs. plasma concentration of drug), additional light doses were calculated for delivery at other times. In phase II, animals were treated at 15, 60, and 120 minutes, using the calculated light doses of 60, 145, and 200 J/cm, respectively. Animals were followed for 2 days to 4 weeks. RESULTS: In Phase I, 80 J/cm at 30 minutes induced total mucosal ablation. In Phase II, light doses of 60, 145, and 200 J/cm induced similar mucosal injuries when delivered at 15, 60, and 120 minutes, respectively. CONCLUSIONS: Effective mucosal ablation in canine esophagus was achieved using Verteporfin and 630 nm light doses of 60, 80, 145, and 200 J/cm when delivered at 15, 30, 60, and 120 minutes after the drug injection, respectively. 相似文献
6.
E C Lipsitz F J Veith T Ohki R T Quintos 《European journal of vascular and endovascular surgery》1999,17(5):413-418
OBJECTIVES: to determine whether clamping proximally or distally on the infrarenal aorta during abdominal aortic aneurysm (AAA) repair increases the overall embolic potential. MATERIALS AND METHODS: a sheath was placed in the mid-infrarenal aorta of 16 dogs. In eight animals a cross-clamp was placed at the aortic trifurcation, and in another eight animals it was placed in the immediate subrenal position. Under fluoroscopy blood flow within the infrarenal aorta was evaluated by contrast and particle injections. Grey-scale analysis was used to calculate contrast density. Particle distribution was followed fluoroscopically and confirmed pathologically. RESULTS: fifty-seven+/-24% of injected contrast remained within the aorta with distal clamping while 97+/-7% did so with proximal clamping (p<0.01). With distal aortic clamping 6.2+/-1. 3 out of 10 injected particles remained within the aorta after 15 seconds and only 0.8+/-0.8 remained after 5 min. With proximal aortic clamping, all 10 of the particles remained within the aortic lumen for the full 5 minutes (p<0.001). CONCLUSIONS: initial distal clamping minimises distal embolisation, but may result in renal and/or visceral embolisation. Initial proximal clamping prevents proximal embolisation and does not promote distal embolisation. We recommend initial proximal clamping in aortic aneurysm surgery to minimise the overall risk of embolisation. 相似文献
7.
In situ light dosimetry during photodynamic therapy of Barrett's esophagus with 5-aminolevulinic acid 总被引:3,自引:0,他引:3
van Veen RL Aalders MC Pasma KL Siersema PD Haringsma J van de Vrie W Gabeler EE Robinson DJ Sterenborg HJ 《Lasers in surgery and medicine》2002,31(5):299-304
BACKGROUND AND OBJECTIVES: Previous studies with PhotoDynamic Therapy (PDT) in bladder and bronchi have shown that due to scattering and reflection, the actually delivered fluence rate on the surface in a hollow organ can be significantly higher than expected. In this pilot study, we investigated the differences between the primary calculated and the actual measured fluence rate during PDT of Barrett's Esophagus (BE) using 23 independent clinical measurements in 15 patients. STUDY DESIGN/MATERIALS AND METHODS: A KTP-dye module laser at 630 nm was used as light source. Light delivery was performed using a cylindrical light diffuser inserted in the center of an inflatable transparent balloon with a length corresponding to the length of the Barrett's epithelium. The total light output power of the cylindrical diffuser was calibrated using an integrating sphere to deliver a primary fluence rate of 100 mW cm(-2). Two fiber-optic pseudo sphere isotropic detectors were placed on the balloon and were used to measure fluence rate at the surface of the esophageal wall during PDT. RESULTS AND CONCLUSIONS: The actual fluence rate measured was 1.5-3.9 times higher than the primary fluence rate for 630 nm. In general, the fluence rate amplification factor decreased with increasing redness of the tissue and was less for shorter diffusers. Fluence rate variations in time were observed which coincided with patients coughing, movement, and esophageal spasms. These factors combined with inter patient variability of the fluence rate measured appears to justify the routine application of this technique in PDT of BE. 相似文献
8.
To evaluate the effects of distal design of a proximally coated femoral component on periprosthetic bone remodeling, we prospectively performed 21 one-stage bilateral total hip arthroplasties using a distally tapered and a distally cylindrical stem with the same proximal design, randomized to side. All hips showed good outcomes clinically and radiographically at the final follow-up, average of 7 years postoperatively. Cancellous condensation was always found in Gruen's zones 2 and 6 around the cylindrical stem and in regions between zones 2 and 3 and between zones 6 and 5 around the tapered stem. Bone mineral density of Gruen's zones 2 and 6 was significantly lower around the tapered stem. These results suggested more distal loading in hips with the tapered stem than in those with the cylindrical stem. 相似文献
9.
The authors report a technique to precisely localize a fistulous opening in the carotid artery. The patient is heparinized and a Prolo catheter is introduced into the internal carotid artery and inflated distal to the approximate site of the fistula. Heparinization allows the balloon to be inflated long enough to obtain and analyze high-quality angiography film without fear of thromboembolism generated by the temporary balloon occlusion. Contrast material injected through the Prolo catheter proximal to the balloon reveals a small segment of cavernous carotid artery between the inflated balloon distally and the fistula proximally. The venous structures are now only faintly opacified and cannot obscure the morbid anatomy of the exact fistulous tear in the carotid artery. If the balloon is placed exactly opposite to the site of the fistula, a standing, stagnant column of dye forms a cast of the cavernous, petrous, and cervical carotid artery. Once the fistula is localized with this method, it may be obliterated by any therapeutic means preferred. If the Prolo catheter is used for intraluminal occlusion, then a transfemoral contralateral carotid angiogram is done before the heparin is reversed to confirm that the balloon has not been placed proxial to the fistula. 相似文献
10.
Critical parameters in the cytotoxicity of photodynamic therapy using a pulsed laser 总被引:1,自引:0,他引:1
Seguchi K Kawauchi S Morimoto Y Arai T Asanuma H Hayakawa M Kikuchi M 《Lasers in medical science》2002,17(4):265-271
.
Photodynamic therapy (PDT) using a pulsed laser is becoming popular, but its cytotoxic effect is still not clear. We therefore
studied the cytotoxicity of PDT using a pulsed laser by changing its irradiation parameters and compared the degrees of cytotoxicity
with those of PDT using continuous-wave (CW) light sources. Mice renal cell carcinoma cells were incubated with PAD-S31, a
water-soluble photosensitiser of which the excitation peak is 670 nm, and were then irradiated with either a tungsten lamp,
a CW diode laser, or a nanosecond pulsed Nd:YAG laser-based optical parametric oscillator system. When the PAD-S31 concentration
and total light dose were constant (12 μg/ml and 40 J/cm2, respectively), the CW laser caused fluence rate-dependent decrease in cellular proliferation until the fluence rate reached
90 mW/cm2, at which point inhibition of cellular proliferation was more than 80%. The cytotoxicity then became almost saturated at
fluence rates of>90 mW/cm2. On the other hand, inhibition of cellular proliferation in samples irradiated with the pulsed laser reached 80% even at
the fluence rate of 15 mW/cm2, and, interestingly, the cytotoxicity paradoxically decreased with increase in the fluence rate. Moreover, the cytotoxicity
in the PDT using the pulsed laser depended on the repetition rate. The inhibition of cellular proliferation by PDT using 30-Hz
irradiation was greater than that by PDT using 5-Hz irradiation when the same fluence rates were used. These results suggest
that the efficacy of PDT using a pulsed laser depends considerably on fluence rate and repetition rate.
Paper received 4 March 2002; accepted after revision 24 May 2002.
Correspondence to: Yuji Morimoto, MD, PhD, Department of Medical Engineering, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama
359-8513, Japan. Tel: +81-42-995-1596; Fax: +81-42-996-5199; e-mail: moyan@interlink.or.jp 相似文献
11.
C D Schuger R T Steinman M H Lehmann L Schuger D Boldea L McMath J R Spears 《Lasers in surgery and medicine》1990,10(2):140-148
Transcatheter direct current electrical shocks for ablation of left-sided accessory pathways in Wolff-Parkinson-White patients have led to serious complications. We report the feasibility of percutaneous transcatheter laser balloon ablation of left-sided accessory pathways from the coronary sinus using a 1,064-nm, continuous wave Nd:YAG laser triple lumen catheter with an optical fiber terminating in a cylindrical diffusing tip within a 2-cm-long, 3-mm-diameter balloon transparent to Nd:YAG laser radiation. In eight mongrel dogs (18 to 31 kg), the laser balloon catheter was positioned via an 8 French guide catheter in the distal and proximal coronary sinus. During balloon inflation, two to three consecutive laser doses of 30 W x 20 sec were applied to each site (cumulative energy, 1,200 to 1,800 J). Coronary angiography, left ventriculography, and coronary sinus injection were performed before and after laser exposure. After percutaneous transcatheter laser balloon ablation, there was no evidence of mitral regurgitation, left circumflex artery, coronary sinus obstruction, or perforation. Coagulation necrosis and/or polymorphonuclear infiltrates involving the atrioventricular groove and left atrial wall over a mean length of 17 mm were present in all eight dogs sacrificed 6 +/- 1 hr postablation. In conclusion, percutaneous transcatheter laser balloon ablation from the coronary sinus is free of immediate major complications and may be feasible for potential interruption of left-sided accessory pathways. 相似文献
12.
Segments ranging from 40 to 70% of the thoracic esophagus were resected in 80 mongrel dogs. End-to-end anastomosis was effected after circular myotomy either proximal or distal, or both proximal and distal, to the anastomosis. Among dogs undergoing resection of 60% of the esophagus, distal myotomy enabled 6 of 8 animals to survive, and combined proximal and distal myotomy permitted 8 of 10 to survive. Cineesophagography was performed in a majority of the 50 surviving animals and showed no appreciable delay of peristalsis at the myotomy sites. When these sites were examined at postmortem examination up to 13 months after operation, 1 dog showed a small diverticulum but none showed dilatation or stricture. It is concluded that circular myotomy holds real promise as a means of extending the clinical application of esophageal resection with end-to-end anastomosis. 相似文献
13.
Salomone Di Saverio Claudio Bianchini Massoni Sergio Boschi Andrea Biscardi Gregorio Tugnoli Michele Masetti Elio Jovine 《Obesity surgery》2014,24(10):1830-1832
A 49-year-old female (weight 81 kg, height 161 cm, BMI 31.2) presented at the emergency department complaining of 2-day history of worsening cramp-like abdominal pain and vomiting. She had not passed stools or flatus in the last 36 h and reported to have had an intra-gastric balloon (BioEnterics Intra-gastric Balloon, Allergan. Inc, Irvine, Calif) inserted 9 months earlier to treat grade I obesity. The balloon was introduced during an upper endoscopy at another institution in Latin America, and she denied having any follow-up since moving to Europe. While in the E.R., an abdominal x-ray and abdominal triple contrast CT scan (with oral water-soluble contrast) showed a complete small-bowel obstruction caused by the distal migration of a foreign body. This was consistent with the intra-gastric balloon impacted in the distal jejunum. Free fluid was also evident. Emergency surgery was mandatory, and a laparoscopic approach was chosen. After identification of the cecum and ileocecal valve, the small intestine was carefully inspected starting from the distal ileum by “run-the-bowel”, proximally. An evident transition point between collapsed and distended bowel loops was identified, and a clear bulging of the bowel wall caused by the deflated and impacted balloon was observed at the site. A transverse enterotomy 3.5 cm in length was performed with laparoscopic scissors, distally to the obstruction site. The balloon was gently pulled out, taking care not to tear or damage the bowel and once removed was placed within an endobag. Laparoscopic enterorrhaphy was performed with double-layer intra-corporeal suture. The postoperative course was uneventful. 相似文献
14.
Teraishi F Fujiwara T Jikuhara A Kamitani S Morino Y Sato K Tanaka N 《The Annals of thoracic surgery》2006,82(3):1119-1121
We report a rare case of esophageal intramural pseudodiverticulosis with esophageal strictures. Barium esophagogram demonstrated multiple flask-shaped diverticula out of the esophageal wall with comprehensive luminal stenosis involving the proximal 8 cm and distal 4 cm of the esophagus. Chest computed tomographic scan demonstrated round wall thickening and several intramural gas collections of the proximal esophagus. Endoscopy revealed a fibrotic stricture and multiple small orifices of pseudodiverticula with mild inflammatory changes. Biopsy specimens showed active chronic inflammatory changes of the mucosa with candidiasis. Dysphagia improved dramatically with esophageal dilation. However, the tiny diverticula did not resolve after treatment. 相似文献
15.
BACKGROUND: This study was designed to compare internal thoracic artery (ITA) flow in different settings of supplemental vein grafting for ITA hypoperfusion. METHODS: Fourteen dogs each received two coronary bypass grafts to the circumflex artery (CFX), using left ITA and vein grafts, and then the proximal CFX was ligated. The animals were divided into two groups. G-I dogs receiving the vein graft proximally to the ITA graft and G-II receiving the vein distally. ITA flow was evaluated regarding 1) effects of competition from the vein graft, and 2) pharmacological or physiological effects on the ITA's contribution to distal perfusion. Flow is expressed as a mean (ml/min). RESULTS: ITA flow was 44.2+/-5.9 in G-I, and 45.7+/-6.5 in G-II (p=ns), when the vein graft was occluded. With a vein graft open, ITA flow decreased to 7.5+/-1.6 in G-I, and 6.8+/-1.8 in G-II (p=ns), and ITA's contribution to total perfusion requirements was 18% in G-I and 16% in G-II. Adenosine (0.2 mg/min/kg) increased the ITA flow in both groups, 18.4+/-3.2, and 16.3+/-3.8, respectively (p=ns), and ITA's contribution to distal perfusion was increased to 32% in G-I and 27% in G-II. In contrast, phenylephrine (0.003 mg/min/kg) decreased ITA flow and ITA's contribution to distal flow in both groups (6.1+/-1.1, 11% vs 6.2+/-1.4, 11%, p=ns), but increased vein flow significantly. Cardiac pacing (150 bpm) increased the ITA flow and ITA's contribution to distal perfusion equally in both groups (8.4+/-1.5, 16% vs 7.6+/-2.6, 15%, p=ns). CONCLUSIONS: Supplemental vein grafting, whether it is placed distally or proximally, limits ITA flow and ITA's contribution to distal perfusion both in the resting heart and during the increased myocardial oxygen demand. 相似文献
16.
BACKGROUND: Photodynamic therapy (PDT) in dermatology is traditionally performed with topical aminolevulinic acid (ALA) and continuous-wave (CW) illumination with blue or red light. Recently, several authors have reported success with laser and other pulsed-light sources for PDT. While the clinical benefits on sun-exposed skin are apparent, no study has demonstrated that the pulsed light sources are responsible for the observed response. STUDY DESIGN: A placebo-controlled study of two pulsed light sources previously reported for PDT: the pulsed dye laser (PDL) or broadband flashlamp filtered intense pulsed light (IPL). Sun-hidden skin was prepared with microdermabrasion and acetone scrub followed by ALA under occlusion. Laser or IPL was delivered under conditions previously reported to produce a clinical response. Control areas were exposed to standardized CW blue light or to no light. A second control area was prepared and received light and the ALA vehicle. RESULTS: IPL and PDL demonstrated a faint dose-response effect on PDT activation, but were less potent than a smaller fluence of CW blue light. Ambient light activated ALA-treated skin. CONCLUSION: Both IPL and PDL are capable of activation of PDT but produce dramatically less PDT reaction than the standard CW blue-light broadband source. Physicians desiring a robust PDT response might select CW sources over pulsed sources. Ambient light may activate a PDT reaction. 相似文献
17.
Kl. -G. Kunze H. Hofstetter I. Posalaky B. Winkler 《European journal of trauma and emergency surgery》1981,7(3):169-180
The blood-flow can be measured with the method of “tracer microspheres”. In 15 adult shephard-dog bastards the blood-flow in the bones of the posterior extremity was determined. The blood-flow in callous bone is 6 times higher than in cortical bone. The values for blood-flow are decreasing from the proximal to the distal end, in cortical as well as in callous bone. In 10 of the 15 dogs the blood-flow was determined after manipulation of the bone. If the medullary cavity of the tibia was evacuated the blood-flow of the corticalis in the bone shaft diminished; it was reduced 3 times more than after removal of the periost. If an osteotomy was performed in the middle of the shaft, the blood-flow was more reduced distally than proximally. In the corticalis of the shaft the blood-flow of the proximal fragment drops only when an osteosynthesis is performed. In extended oblique fractures the upper ends of the fragments — proximally as well as distally — are endangered by a reduction of the blood-flow. 相似文献
18.
Optimum ratio of distraction in double level tibial lengthening 总被引:2,自引:0,他引:2
Choi IH Sohn CS Chung CY Cho TJ Lee JW Lee DY 《Clinical orthopaedics and related research》1999,(368):240-246
The authors reviewed 43 double level tibial lengthenings by Ilizarov technique in 34 consecutive patients (6-31 years old), and investigated the factors affecting regenerate bone healing to determine the optimum ratio of distraction rate or magnitude of lengthening at the proximal and distal osteotomy sites. Length gain averaged 6.1 cm (range, 2.5-12.3 cm), equivalent to a 28% increase of the segment. The variables investigated included age, gender, concomitant deformity correction, etiology, and the amount of length gain. The healing index averaged 1.8 months per centimeter proximally and 2.8 months per centimeter distally. Age and the amount of length gain affected the healing index at proximal and distal lengthening sites. However, the proximal to distal healing index ratio, which averaged 0.72, was not affected by any parameters investigated. This study suggests that to minimize external fixation treatment time, the distraction rate, or amount of length gain, of the distal osteotomy site should be approximately 3/4 that of the proximal site in the double level tibial lengthening. 相似文献
19.
Sean S. Kohles Mark D. Markel Michael G. Rock Edmund Y. S. Chao Ray Vanderby 《Journal of orthopaedic research》1994,12(6):834-843
The structural stiffness and the stiffness of the osteotomy site after six types of reconstruction of the proximal femur were compared by testing in axial compression, mediolateral bending, and axial torsion in a canine model. An osteotomy was carried out for 25, 50, or 75% of the length of each femur, and the proximal portion was replaced by one of five allograft/endoprosthetic composites or a segmental replacement. The reconstructions included (a) a composite press-fit proximally and cemented distally, (b) a composite cemented proximally and distally, (c) a composite cemented proximally and fixed with two plates at the allograft-host bone interface, (d) a composite cemented proximally and secured distally with bicortical screws, (e) a composite secured proximally and distally with bicortical screws, and (f) a segmental prosthesis cemented into the distal femur. The results showed that the segmental reconstruction and the reconstruction with double-plate fixation and a cemented endoprosthesis were structurally stiffer and had greater stiffness of the osteotomy site than the other reconstructions. In comparison, reconstructions that involved cement alone or cement and press-fit techniques generally were more compliant than the others, both structurally and at the osteotomy site. 相似文献
20.
Takamizawa S Yamanouchi E Muraji T Nishijima E Satoh S Tsugawa J 《Journal of pediatric surgery》2007,42(5):769-772
A 25-month-old boy with long gap esophageal atresia developed severe esophageal stenosis refractory to balloon dilatations after definitive esophagoesophagostomy. At 33 months of age, the patient had a magnetic compression revision anastomosis, in which a pair of 2 cylindrical Samarium-cobalt rare-earth 320 mT (3200 G) magnets, 15 × 5 mm (diameter × thickness), were placed in the esophagus to compress the scar tissue of the anastomosis. The magnets were retrieved 34 days after the magnetic compression revision anastomosis procedure. For 3 months, the patient subsequently had balloon dilatations to prevent restenosis, and he has been able to eat normally by mouth without further balloon dilatations since then. 相似文献