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At least 595 records · Page 33Linked to original sources

PubMed2005

Cost comparison of anterior cruciate ligament reconstruction: autograft versus allograft.

PURPOSE: To compare the economic costs associated with anterior cruciate ligament (ACL) reconstruction using either autograft or allograft. The surgical costs are reported, including charge categories, for each procedure. All operations were performed in the Southern United States of America. TYPE OF STUDY: Evaluation of cost data collected from a group of patients participating in a prospective, nonrandomized trial. METHODS: A total of 122 patients with ACL-deficient knees undergoing surgical reconstruction using either bone-patellar tendon-bone autograft (n = 86) or freeze-dried Achilles tendon allograft (n = 37) were analyzed (1 patient underwent 2 allograft reconstructions). Patient selection for groups was based on the physician performing the surgery (2 surgeons performed autografts and 1 performed allografts). Groups were compared with respect to age, sex, race, and occupation. Hospital charge data were retrieved from the billing department and divided into various categories for comparison of the 2 groups. RESULTS: The mean hospital charge for ACL reconstruction was 4,622 dollars for allograft and 5,694 dollars for autograft (P < .0001). Differences included increased operating room time and a greater likelihood of overnight hospitalization for autograft procedures. This was slightly offset by higher charges for operating room supplies for allograft reconstructions owing to the cost of the graft itself. CONCLUSIONS: Allograft reconstruction of the ACL was significantly less expensive than autograft bone-patellar tendon-bone reconstruction. Allograft ACL reconstruction is a less costly alternative to autograft reconstruction. LEVEL OF EVIDENCE: Level IV, economic analysis with no sensitivity analysis.

Adult↗

PubMed2005

Clinical outcomes after isolated arthroscopic single-bundle posterior cruciate ligament reconstruction.

PURPOSE: The purpose of this study was to evaluate the clinical outcomes after arthroscopic single-bundle posterior cruciate ligament (PCL) reconstruction in patients with isolated grade III PCL injuries. TYPE OF STUDY: Retrospective review. METHODS: Twenty-one patients who underwent an isolated arthroscopic single-bundle PCL reconstruction for the treatment of a grade III PCL injury between 1989 and 1998 were included in the study. There were 15 male and 6 female patients with an average age of 38 years (range, 20 to 62 years). The length of follow-up was 5.9 years (range, 2.6 to 11 years), and the average time from injury to surgery was 4.5 years (median, 1.3 years; range, 2 weeks to 25 years). All patients completed a subjective evaluation and 14 patients returned for a physical examination and radiographs. One patient underwent an acute reconstruction (<3 weeks), 4 had a subacute (<3 months), and 16 underwent a chronic (>3 months) reconstruction. The anterolateral bundle of the PCL was reconstructed using an Achilles tendon allograft passed through femoral and tibial bone tunnels. RESULTS: The overall average Activities of Daily Living Scale (ADLS), Sports Activities Scale (SAS), and SF-36 scores were 79.3, 71.6, and 98 points, respectively. There was a significant difference identified when the ADLS (91.3 v 75.6) and the SAS (90.4 v 65.8) scores of the subacute/acute group were compared with those of the chronic reconstruction group. Using the International Knee Documentation Committee (IKDC) subjective assessment, 57% of the patients had normal/near normal knee function, and 62% had a normal/near normal activity level. The average extension and flexion losses were 1 degrees and 5 degrees , respectively. Instrumented laxity examination revealed that 62% had less than a 3-mm and 31% had a 3- to 5-mm side-to-side difference in corrected posterior displacement. Radiographs at follow-up showed that 75% had normal/near normal findings according to IKDC guidelines. CONCLUSIONS: The clinical outcomes after arthroscopic single-bundle PCL reconstruction in this study produced a satisfactory return of function and improvement in symptoms. All patients in this study had improved laxity of at least 1 grade. When compared with chronic reconstructions, acute reconstructions had statistically significant better ADLS and SAS scores. LEVEL OF EVIDENCE: IV, case series.

Achilles Tendon↗

PubMed2006

Techniques of reconstruction for inadequate donor left atrial cuff in lung transplantation.

BACKGROUND: An inadequate donor left atrial (LA) cuff due to an anatomical abnormality of the pulmonary vasculature or technical errors at the time of procurement can exclude the lungs from transplant. This study aims to describe the incidence, efficacy, and various techniques of LA cuff reconstruction in lung transplantation. METHODS: A total of 637 pulmonary venous anastomosis in 405 consecutive lung transplants from January 1995 to July 2005 were reviewed. Comparison between the patients who required LA cuff reconstruction (reconstruction group) or who did not (no-reconstruction group) was made in posttransplant outcomes. RESULTS: An overall incidence of requirement of LA cuff reconstruction was 2.7% (4% on the right, 1% on the left, p = 0.03). Seventy-one percent of LA inadequacy was corrected using a pericardial patch on the anterior LA cuff wall; the remainder required complicated reconstruction for separated/short pulmonary veins to create a new LA cuff. There was no significant difference between the reconstruction and no-reconstruction groups, respectively, in oxygenation (329 +/- 28, 337 +/- 10, p = 0.81), duration of intubation and intensive care unit stay (p = 0.54, p = 0.89, respectively), 30-day mortality (12%, 6%, p = 0.30), and 5-year survival (57%, 52%, p = 0.80). CONCLUSIONS: Inadequate donor LA cuff is an infrequent but potentially serious complication in lung transplantation. Donor LA cuff reconstruction using donor pericardium or pulmonary artery remnant is a useful technique to salvage surgically marginal lungs without affecting early and late posttransplant outcomes. These lungs should not be excluded from transplantation.

Adult↗

PubMed2005

Speech and swallowing following radial forearm flap reconstruction of major soft palate defects.

Velopharyngeal function is often compromised by the resection and reconstruction of oropharyngeal and palatal tumours. While free tissue transfer has improved the outcomes of head and neck reconstruction. In general, palatal reconstruction remains a challenge. Velopharyngeal function was analysed in eight patients following microsurgical reconstruction of defects of between 50 and 100% of the soft palate. The radial forearm fasciocutaneous free flap was used in all cases. The outcome of reconstruction was analysed by patient questionnaire and with standardised tests of speech and swallowing function. Velopharyngeal function post-operatively ranged from poor to near normal. Poor function appeared due to the loss of active elevation and contracture of the reconstructed palate producing failure of velopharyngeal closure during swallowing and speech. The results emphasise the limitations of reconstruction of a dynamic structure such as the soft palate with the static fold of skin and soft tissue produced by a fasciocutaneous flap. The relatively poor results obtained suggest that an anatomical approach to soft palate reconstruction is inadequate and reduction of the calibre of the velopharyngeal aperture is required to compensate for the lack of mobility in the reconstructed palate.

Carcinoma, Squamous Cell↗

PubMed2005

Vascularised free fibular flap in bone resection and reconstruction.

This paper compares allograft alone and in combination with vascularised free fibular flaps (FFF) to reconstruct long bone defects after tumour excision. We present 33 cases, 21 of these patients had reconstruction with an allograft alone as the initial procedure. Nine patients underwent reconstruction with FFF plus allograft plus iliac crest bone graft (ICG), two patients underwent reconstruction with a FFF and ICG and one patient underwent reconstruction with an allograft, a pedicled fibular flap and a FFF. The allograft was obtained from the Queensland Bone Bank and had been irradiated to 25 000Gy. In our experience (N=21) the complication rates with allograft alone were: delayed union 3, nonunion 7, fractured allograft 6, infection requiring resection of the allograft 3, other infections 2. The revision rate was 48% (10 cases of which five required a free fibular flap) and an average of 1.8 revision procedures were required. In the lower limb cases, the mean time to full weightbearing was 20 months and 40% were full weightbearing at 18 months. We felt that the high complication rate compared with other series may have been related to the irradiation of the graft. FFFs were used in 18 cases, 12 cases were primary reconstructions and six were revision reconstructions. The mean fibular length was 19.4 cm (range 10-29 cm). There were no flap losses and the FFF united at both ends of 11 of 12 primary reconstruction cases. One case had nonunion at one end, giving a union rate of 96% (23 of 24 junctions). When a FFF was used in combination with an allograft as a primary reconstruction, the allograft nonunion rate was 50% (five of 10 cases). The mean time to full weightbearing in the lower limb cases was 7.5 months and 100% were full weightbearing at 18 months. The FFF hastens time to full weightbearing but does not appear to affect the complication rates of allograft. The number of revision procedures required is reduced in the presence of a FFF and is the latter is a useful technique for the salvage of refractory cases.

Adolescent↗

PubMed2006

A combined flap reconstruction for full-thickness defects of the medial canthal region.

The medial canthus is an aesthetically and functionally important area. Adequate consideration of the local anatomy is essential when reconstructing this area. We developed a combined flap technique with a simple combination of standard flaps for the treatment of extensive defects of the nose and upper and lower eyelids, including full-thickness medial canthus defect. In our technique, a median forehead island flap is used for the nasal region, the anterior surface of the eyelid is reconstructed along aesthetic unit, and the posterior surface is reconstructed with a palatal mucoperiosteal graft. A cheek flap is then used for the reconstruction of the lower eyelid. When reconstructing a small defect of the upper eyelid, the upper eyelid is advanced, while a V-Y advancement flap within the upper eyelid is used for a large defect. To reconstruct the acute angle of the medial canthus, a 0.3 mm titanium wire was passed through the tip of the tarsal plate of the upper and lower eyelids to be reconstructed and was fixed in the perforated nasal bone on the affected side. Using this technique, the acute angle of the medial canthus is well preserved after surgery, and is located symmetrically with its counterpart on the intact side. Our technique provides good reconstructive results and should serve as a valid alternative for the reconstruction of this area.

Aged↗

PubMed2005

Effects of the posterior cruciate ligament reconstruction on the biomechanics of the knee joint: a finite element analysis.

BACKGROUND: Previous experimental studies have been conducted to evaluate the biomechanical effects of posterior cruciate ligament reconstruction; but no consensus has been reached on the preferred method of reconstruction. METHODS: The 3D finite element mesh of a knee joint was reconstructed from computed tomography and magnetic resonance images. The ligaments were considered as hyperelastic materials. The tibiofemoral and patellofemoral joints were modeled with large sliding contact elements. The 3D model was used to simulate knee flexion from 0 degrees to 90 degrees in four cases: a knee with a "native" posterior cruciate ligament, a resected posterior cruciate ligament, a reconstructed single graft posterior cruciate ligament, and a reconstructed double graft posterior cruciate ligament. FINDINGS: A resected posterior cruciate ligament induced high compressive forces in the medial tibiofemoral and patellofemoral compartments. The pressures generated in the tibiofemoral and patellofemoral compartments were nearly the same for the two reconstruction techniques (single graft and double graft). The single graft resulted in lower tensile stresses inside the graft than for the double graft. INTERPRETATION: Firstly, a resected posterior cruciate ligament should be replaced to avoid excessive compressive forces, which are a source of cartilage degeneration. Secondly, the two types of posterior cruciate ligament reconstruction techniques partially restored the biomechanics of the knee in flexion, e.g. contact pressures were restored for pure flexion of the knee. The reconstruction techniques therefore partially restore the biomechanics of the knee in flexion. A double graft reconstruction is subjected to the highest tensile stresses.

Compressive Strength↗

PubMed2006

Segmentation and three-dimension reconstruction of Chinese digitized human cerebrum.

OBJECTIVE: A 3D digitized visible model of human cerebrum was built to provide anatomical structure for making plans of cerebral surgical operation and realizing accurate simulation of cerebrum on computer. METHODS: Transverse sectional anatomy data of the cerebrum were chosen from the first Chinese visible human (one male and one female). Semi-automated segmentation and Photoshop software were selected to segment cerebral cortex, white matter, basal nuclei, lateral ventricle, hippocampus, etc. On personal computer, the segmented structures were reconstructed in 3D with volume rendering reconstruction and surface rendering reconstruction. RESULTS: Two accurately segmented images of the main structures of cerebrum were completed. The reconstructed structures can be displayed singly, in small groups or as a whole and can be continuously rotated in 3D space at different velocities. CONCLUSION: Combining volume-rendering reconstruction with surface rendering reconstruction overcomes the defects of surface rendering reconstruction that lack of internal anatomical information, which provides a new method for 3D reconstruction. The reconstructed cerebrum and the main internal structures are realistic, which demonstrates the natural shape and exact position of the structures. It provides an accurate model for the automated segmentation algorithmic study and provides a digitized anatomical mode of cerebrum.

China↗

PubMed2006

Craniofacial reconstruction using a combined statistical model of face shape and soft tissue depths: methodology and validation.

Forensic facial reconstruction aims at estimating the facial outlook associated with an unidentified skull specimen. Estimation is generally based on tabulated average values of soft tissue thicknesses measured at a sparse set of landmarks on the skull. Traditional 'plastic' methods apply modeling clay or plasticine on a cast of the skull, approximating the estimated tissue depths at the landmarks and interpolating in between. Current computerized techniques mimic this landmark interpolation procedure using a single static facial surface template. However, the resulting reconstruction is biased by the specific choice of the template and no face-specific regularization is used during the interpolation process. We reduce the template bias by using a flexible statistical model of a dense set of facial surface points, combined with an associated sparse set of skull-based landmarks. This statistical model is constructed from a facial database of (N = 118) individuals and limits the reconstructions to statistically plausible outlooks. The actual reconstruction is obtained by fitting the skull-based landmarks of the template model to the corresponding landmarks indicated on a digital copy of the skull to be reconstructed. The fitting process changes the face-specific statistical model parameters in a regularized way and interpolates the remaining landmark fit error using a minimal bending thin-plate spline (TPS)-based deformation. Furthermore, estimated properties of the skull specimen (BMI, age and gender, e.g.) can be incorporated as conditions on the reconstruction by removing property-related shape variation from the statistical model description before the fitting process. The proposed statistical method is validated, both in terms of accuracy and identification success rate, based on leave-one-out cross-validation tests applied on the facial database. Accuracy results are obtained by statistically analyzing the local 3D facial surface differences of the reconstructions and their corresponding ground truth. Identification success rate is obtained by comparing, based on correlation, Euclidean distance matrix (EDM) signatures of the reconstructed and the original 3D facial surfaces in the database. A subjective identification success rate is quantified based on face-pool tests. Finally a qualitative comparison is made between facial reconstructions of a real-case skull, based on two typical static face models and our statistical model, showing the shortcomings of current face models and the improved performance of the statistical model.

Adolescent↗

PubMed2006

The impact of immediate breast reconstruction on the technical delivery of postmastectomy radiotherapy.

PURPOSE: To quantify the impact of immediate breast reconstruction on postmastectomy radiation therapy (PMRT) planning. METHODS: A total of 110 patients (112 treatment plans) who had mastectomy with immediate reconstruction followed by radiotherapy were compared with contemporaneous stage-matched patients who had undergone mastectomy without intervening reconstruction. A scoring system was used to assess optimal radiotherapy planning using four parameters: breadth of chest wall coverage, treatment of the ipsilateral internal mammary chain, minimization of lung, and avoidance of heart. An "optimal" plan achieved all objectives or a minor 0.5 point deduction; "moderately" compromised treatment plans had 1.0 or 1.5 point deductions; and "major" compromised plans had > or =2.0 point deductions. RESULTS: Of the 112 PMRT plans scored after reconstruction, 52% had compromises compared with 7% of matched controls (p < 0.0001). Of the compromised plans after reconstruction, 33% were considered to be moderately compromised plans and 19% were major compromised treatment plans. Optimal chest wall coverage, treatment of the ipsilateral internal mammary chain, lung minimization, and heart avoidance was achieved in 79%, 45%, 84%, and 84% of the plans in the group undergoing immediate reconstruction, compared respectively with 100%, 93%, 97%, and 92% of the plans in the control group (p < 0.0001, p < 0.0001, p = 0.0015, and p = 0.1435). In patients with reconstructions, 67% of the "major" compromised radiotherapy plans were left-sided (p < 0.16). CONCLUSIONS: Radiation treatment planning after immediate breast reconstruction was compromised in more than half of the patients (52%), with the largest compromises observed in those with left-sided cancers. For patients with locally advanced breast cancer, the potential for compromised PMRT planning should be considered when deciding between immediate and delayed reconstruction.

Breast Neoplasms↗

PubMed2006

Reconstruction of the interosseous ligament unloads metallic radial head arthroplasty and the distal ulna in cadavers.

PURPOSE: Longitudinal radioulnar dissociation may result when a compressive load to the hand results in excessive proximal migration of the radius with interosseous ligament (IOL) disruption and radial head fracture. Interosseous ligament reconstruction has been proposed to restore more normal forearm mechanics. The objective of this study was to evaluate the effect of IOL reconstruction on compressive load transfer through the forearm after excision and metallic replacement of the radial head in cadavers. METHODS: In 8 cadaveric forearms, 138 N of compressive load was applied to the hand in neutral forearm rotation and neutral elbow varus-valgus alignment. We measured proximal radial migration and 3-dimensional force vectors acting on the distal radius, distal ulna, IOL, proximal radius, and proximal ulna. The experiment was repeated in order for 5 conditions: (1) with the IOL intact, (2) with the IOL reconstructed with a double-bundle flexor carpi radialis construct, (3) with the radial head excised, (4) after metallic radial head arthroplasty, and (5) after cutting the IOL reconstruction. Analysis of variance was used for statistical comparisons. RESULTS: With the IOL intact the resultant load in the distal radius was 94% +/- 3% of hand load, with 75% +/- 2% transmitted to the proximal radius. Double-bundle flexor carpi radialis reconstruction effectively restored this relationship. After radial head excision the resultant distal radius load decreased whereas great increases were seen in the resultant distal ulna load, the resultant load in the IOL reconstruction, the resultant load in the proximal ulna, and proximal radial migration. Force continued to transfer through the proximal radius transversely, with a 400% increase in transverse force, a consequence of abutment of the radial stump caused by proximal radioulnar convergence (there was no contact at the capitellum). After radial head arthroplasty loads transferred across the wrist remained closer to intact but the resultant load on the distal ulna and proximal radius remained increased. With cutting of the IOL reconstruction transverse forces in the forearm became negligible, the resultant distal ulna load increased by 50%, and the resultant radial head load increased by 25%. Proximal migration of the radius was small and was increased by 4.6 mm with radial head excision and by 1 mm after radial head replacement compared with the IOL-reconstructed, radial head-intact state. CONCLUSIONS: Interosseous ligament reconstruction may help improve treatment of longitudinal radioulnar dissociation but remains an experimental procedure.

Aged↗

PubMed2005

Phase-constrained parallel MR image reconstruction.

A generalized method for phase-constrained parallel MR image reconstruction is presented that combines and extends the concepts of partial-Fourier reconstruction and parallel imaging. It provides a framework for reconstructing images employing either or both techniques and for comparing image quality achieved by varying k-space sampling schemes. The method can be used as a parallel image reconstruction with a partial-Fourier reconstruction built in. It can also be used with trajectories not readily handled by straightforward combinations of partial-Fourier and SENSE-like parallel reconstructions, including variable-density, and non-Cartesian trajectories. The phase constraint specifies a better-conditioned inverse problem compared to unconstrained parallel MR reconstruction alone. This phase-constrained parallel MRI reconstruction offers a one-step alternative to the standard combination of homodyne and SENSE reconstructions with the added benefit of flexibility of sampling trajectory. The theory of the phase-constrained approach is outlined, and its calibration requirements and limitations are discussed. Simulations, phantom experiments, and in vivo experiments are presented.

Algorithms↗

PubMedDate not supplied

A biomechanical comparison of four reconstruction techniques for the medial collateral ligament-deficient elbow.

The initial strength of the intact medial collateral ligament (MCL) of the elbow and the strength of 4 reconstruction techniques were compared. Twenty cadaveric upper extremities were mounted in a custom jig with the elbow at 90 degrees , and a pneumatic cyclic valgus loading protocol was used. The mean peak load to failure was 142.5+/-39.4 N for the intact ligaments and 53.0+/-9.5 N for the docking reconstructions, 52.5+/-10.4 N for the EndoButton reconstructions, 41.0+/-16.0 N for the interference screw reconstructions, and 33.3+/-7.1 N for the figure-eight reconstructions. The peak load to failure of the MCL reconstructions was inferior compared with the intact ligament (P<.001). No difference in strength was found between the docking and single-strand medial collateral reconstruction with the use of an EndoButton for ulnar fixation (P>.05, beta=.14). Both of these reconstruction methods were stronger than the interference screw or figure-eight technique (P<.004). The optimal fixation method for a single-strand MCL reconstruction may require improved interference screws or a modified EndoButton procedure.

Bone Screws↗

PubMed2004

Anterior cruciate ligament graft impingement against the posterior cruciate ligament: diagnosis using MRI plus three-dimensional reconstruction software.

OBJECTIVE: The purpose of this study was to evaluate anterior cruciate ligament (ACL) impingement against the posterior cruciate ligament (PCL) with the knee in an extended position, which arthroscopy cannot detect. MATERIALS AND METHODS: Ten normal knees and 30 ACL-reconstructed knees were assessed using MR imaging. The three-dimensional reconstruction of the ACL, PCL, femur and tibia were carried out using commercially available three-dimensional reconstruction software. Anterior cruciate ligament impingement against the PCL was graded into three categories: Grade 1, some space between the ligaments; Grade 2, no space between the ligaments, and the reconstructed ACL ran straight; and Grade 3, the reconstructed ACL did not run straight. The angle of the reconstructed ACL against the tibial plateau was also measured. RESULTS: All normal knees were classified as Grade 1. The 30 reconstructed knees were classified as follows: Grade 1, 12 cases; Grade 2, 7 cases; and Grade 3, 11 cases. The mean angle of the Grade 3 reconstructed ACL knees was significantly more vertical against the tibia as compared with the Grade 1 knees (P<.05). The postoperative KT-2000 side-to-side difference of the Grade 3 knees (2.8+/-4.5 mm) was larger than that of the Grade 1 knees (0.2+/-1.7 mm) and Grade 2 knees (-0.6+/-2.2 mm), but no statistically significant difference could be detected between the three groups in the postoperative KT-2000 data. CONCLUSION: This method is useful to evaluate ACL impingement against PCL, which cannot be detected by conventional arthroscopy during the operation. The surgeon should pay careful attention to the coronal angle of the reconstructed ACL.

Adolescent↗

PubMed1997

Effect of surgical reconstruction on flow profiles in the aorta using magnetic resonance blood tagging.

BACKGROUND: The aorta that has undergone an aorta-pulmonary artery anastomosis may not exhibit the same velocity profile as the nonreconstructed aorta, whose velocity profile is thought to be uniform across the vessel diameter (plug flow). This may have an impact on fluid dynamics and will alter Doppler flow calculations. Our objective was to determine the impact of surgical reconstruction on the velocity and flow profiles of the reconstructed ascending and descending aorta. METHODS: Using a magnetic resonance imaging tagging technique that labels flowing blood (bolus tagging), we studied 22 patients (mean age, 8.6 +/- 4.7 years) who had had a Fontan procedure. A cine sequence labeled the blood and acquired the image after 20 ms in the middle of the ascending aorta and behind the left atrium in the descending aorta. The repetition time was 50 ms. RESULTS: The reconstructed ascending aorta displayed a velocity profile skewed anteriorly, whereas in the nonreconstructed aorta, the velocity profile was flat. Reconstructed aortas also displayed flows that were higher anteriorly, took a longer time to reach maximum velocity, and were less like "plug" flow than the nonreconstructed aorta. The descending aorta, regardless of whether aortic reconstruction was present, displayed velocity profiles (at various phases of systole) skewed posteriorly. CONCLUSIONS: The reconstructed aorta displays disturbed flow, and the velocities across the ascending aortic diameter are more varied than those in aortas without reconstruction and are skewed anteriorly. The descending aortic velocity profile in children is skewed posteriorly, regardless of whether aortic reconstruction is present. This information may help design and build a "better" aortic reconstruction.

Adolescent↗

PubMed1994

Right common carotid artery reconstruction after extracorporeal membrane oxygenation: vascular imaging, cerebral circulation, electroencephalographic, and neurodevelopmental correlates to recovery.

OBJECTIVE: Right common carotid artery (RCCA) ligation after extracorporeal membrane oxygenation by venoarterial bypass may contribute to lateralized cerebral injury. Reconstruction of this artery after extracorporeal membrane oxygenation has proved feasible but has not been evaluated for neurologic outcome in any substantial series of infants. METHODS: We evaluated RCCA reconstruction in 47 infants treated with ECMO and compared their cerebrovascular and neuroanatomic imaging findings, electroencephalograms, and developmental outcomes with those of 93 infants who had no reconstruction. SUMMARY RESULTS: Color Doppler blood flow imaging revealed that carotid artery patency was usually obtained after RCCA reconstruction. Right internal carotid and bilateral anterior and middle cerebral arterial blood flow velocities were generally higher, and were more symmetrically distributed in infants with reconstructed RCCA. Electroencephalography did not disclose an increased risk of deterioration or marked abnormalities in infants after reconstruction, nor were neuroimaging findings consistent with an increased number of either focal or generalized abnormalities. Neurodevelopmental follow-up revealed no differences in the incidence of delays between those with a reconstructed RCCA and those with a ligated RCCA during the first year of life. CONCLUSIONS: Reconstruction of the RCCA after extracorporeal membrane oxygenation may facilitate normal distribution of cerebral blood flow through the circle of Willis, and may augment both left and right middle cerebral artery blood flow immediately after decannulation. The long-term consequences of either ligation or reconstruction of the RCCA will require careful scrutiny, however, before either course is recommended routinely.

Blood Flow Velocity↗

PubMed1999

Modeling of jaw biomechanics in the reconstructed mandibulectomy patient.

STATEMENT OF PROBLEM: Biomechanics of occlusal force and indirect calculation of temporomandibular joint loading in patients after surgery for head and neck cancer is poorly understood. PURPOSE: This study compared occlusal force values of 6 mandibulectomy subjects with reconstructed mandibles to 6 noncancer subjects with intact mandibles and reports occlusal force predictions from a developed computer model simulation of both a mandibulectomy subject with a reconstructed mandible and noncancer subject with an intact mandible. MATERIAL AND METHODS: Maximum occlusal force was recorded at the first molar and incisal edge in 6 mandibulectomy subjects who had bony reconstruction of the mandible and 6 noncancer subjects with an intact mandible. Clinical data were then qualitatively compared with occlusal force values generated from an existing computer model simulating an average adult, and a developed model simulating an average mandibulectomy subject who had bony reconstruction of the mandible. The biomechanical parameters modeled also included an estimation of joint force magnitude and direction when biting with maximal force on the first molar. RESULTS: Clinical data revealed no significant differences in occlusal force between the 6 mandibulectomy subjects with bony reconstruction of the mandible and 6 noncancer subjects with an intact mandible; however, average molar and incisal occlusal force values were 22% and 32% less in mandibulectomy subjects with bony reconstruction. Computer simulations of a reconstructed mandibulectomy subject predicted that reconstructed subjects would have 45% less molar occlusal force, 50% less incisal occlusal force, and a higher joint/tooth force ratio compared with a simulated noncancer patient with an intact mandible. CONCLUSIONS: There were no significant differences in first molar or incisal occlusal force between reconstructed mandibulectomy subjects and noncancer subjects with intact mandibles. Trends calculated from computer simulations were consistent with clinical findings.

Adult↗

PubMed1996

Truncus arteriosus repair: influence of techniques of right ventricular outflow tract reconstruction.

Fifty-six consecutive patients underwent total correction of truncus arteriosus. Median age at repair was 41 days, with a range of 2 days to 8 months. In 71% the operation was done in the first 2 months of life. Nine patients had complex forms of truncus and 11 patients had aortic insufficiency. The truncal aortic root was transected, which provides a clear exposure of the coronary ostia. The aorta was reconstructed by direct end-to-end anastomosis, and the truncal valve was preserved in every case. Several different techniques were used for pulmonary reconstruction, including three types of anatomic reconstruction of the pulmonary valve with a trisigmoid leaflet system and two types of nonanatomic reconstruction. The anatomic techniques included use of 33 Dacron valved conduits, eight homograft valved conduits, and one porcine aortic root bioprosthesis. The nonanatomic reconstructions included direct anastomosis to the right ventricle in nine patients and insertion of autologous pericardial valved conduits in five. The hospital mortality was 16% (9/56; 95% confidence limits, 2% to 30%). Multivariate analysis outlines two independent incremental risk factors for hospital death: nonanatomic pulmonary valve reconstruction techniques and age younger than 1 month. The hospital mortality was 7.1% in the group with anatomic pulmonary valve reconstruction versus 43% in the group with nonanatomic pulmonary valve reconstruction (p = 0.015). The hospital mortality was 5.7% in those older than 1 month versus 33% in those younger than 1 month of age (p = 0.04). There were two late deaths. The actuarial freedom from reoperation and angioplasty at 7 years was 100% for patients receiving pericardial conduits, 80% for those undergoing direct anastomosis, 77% for those receiving Dacron conduits, and only 43% for those receiving homografts (p = 0.02). In conclusion, anatomic reconstruction of the pulmonary valve seems important at the time of the operation, age younger than 1 month remains an incremental risk factor, and the truncal valve can be preserved.

Age Factors↗