Postsurgical Adaptation Research Articles

Changes in Pharyngeal Airway After Mandibular Setback Surgery: A Retrospective Cephalometric Study

Aim: To cephalometrically evaluate the alterations taking place in the pharyngeal airway space, hyoid bone, soft palate, and head posture after mandibular setback surgery (bilateral sagittal split osteotomy) for correction of mandibular prognathism, as well as to evaluate the immediate postsurgical and more than 6 months postsurgical adaptations of these structures. Setting and Design: A retrospective cephalometric study. Materials and Method: The study group consisted of 40 nongrowing patients (20 females and 20 males) with mandibular prognathism and ANB less than or equal to –2 degree for which mandibular setback surgery by bilateral sagittal split ramus osteotomy was performed along with fixed appliance therapy. There presurgical (T1), immediate postsurgical (T2), and more than 6 months postsurgical (T3) lateral cephalograms were analyzed. Statistical Analysis Used: Intragroup comparison was done by paired t-test. Results: Skeletal measurements after orthognathic surgery remained stable in the long term. It was evident that mandibular setback surgery narrowed the pharyngeal airway; however, these changes were not significant except at the base of the tongue. During the follow-up airway measurements at the base of the tongue, the intersection of tongue at the inferior border of mandible and the vallecula increased but they did not reach the presurgical values. Soft palate length increased significantly after surgery. Angulation of soft palate to nasal line also increased significantly following surgery but decreased during follow-up. Extension of the head occurred after surgery which was maintained even at long term. Conclusion: Careful analysis of airway should be performed, particularly in connection with large anteroposterior discrepancies and in those who have risk factors for development of obstructive sleep apnea. Such cases should be corrected by combined maxillary and mandibular osteotomies.

Urodynamic 4D-CT evaluation: 320-row area detector CT scanner combined with PhyZiodynamics software analysis provides an innovative system to evaluate urinary flow and outlet obstructions

Background Evaluation of the morphology of the lower urinary tract as well as the movements associated with urination are required for the symptomatic diagnosis of lower urinary tract obstruction as well as the assessment of postoperative adaptation. However, no tool currently exists for direct and easy patient evaluation. Purpose To evaluate lower urinary tract obstruction and postoperative adaptation using a four-dimensional (4D) virtual reality urination image (urodynamic 4D-CT image). Material and Methods We used a 320-row area detector CT scanner and PhyZiodynamics image analysis software to perform 197 urodynamic 4D-CT examinations on 175 first-time patients between January 2014 and March 2017. Results A comparison of the obtained images before and after holmium laser enucleation of the prostate revealed the morphological changes due to prostate enucleation and enabled visualization of the ideal urination conditions, showing that the anatomical structural changes during urination and the opening of the urethra play a major role in improving voiding function. Conclusion Using low-dosage radiation, the sharply defined moving image obtained via urodynamic 4D-CT examination can be utilized as a physiological diagnostic tool to evaluate a series of urinary movements from any angle between the prostate, urethra, and bladder in a unitary manner with the time axis added. There was negligible patient impact. This technique could provide new opportunities for the diagnosis of lower urinary tract symptoms and post-surgical adaptation assessment.

Pediatric epilepsy surgery patients show normal psychosocial development at long-term follow-up despite dissatisfying family dynamics

Drug-resistant pediatric epilepsy involves unpredictable seizures and long-term medical management. Both factors can alter a child's psychosocial development and the dynamics of the family, to the detriment of patient and family wellbeing. While drug-resistant pediatric epilepsy can be successfully treated by neurosurgery in some cases, the outlook for psychosocial and family functioning after surgery remains unclear. A total of 163 participants across four groups took part in the current study: these were (i) individuals who had undergone surgical treatment of drug-resistant focal seizures approximately five years prior as children, and were now largely adolescents or young adults (‘Patients’; n = 23), (ii) their caregivers (‘Patient Caregivers’; n = 27), (iii) healthy individuals of similar age and gender to the Patients (‘Controls’; n = 53), and (iv) their caregivers (‘Control Caregivers’; n = 60). Based on similar software validated in adults, we built an interactive computer program, ‘Living with Epilepsy’, to evaluate the achievement of age-specific developmental tasks in Patients relative to their peers. The Family Adaptability and Cohesion Scale measured family dynamics. The findings showed that in the context of seizure freedom, after pediatric epilepsy surgery, Patients are similar to their healthy peers in terms of attaining developmental tasks, with no differences between the Patient and Control groups (P > .05). Family dynamics, however, seemed resistant to postsurgical adaptation, with Patients reporting lower levels of balanced family dynamics (cohesion, flexibility) and higher rates of unbalanced family dynamics (disengagement, chaos, rigidity, enmeshment) relative to Patient Caregivers (P < .001–0.041), and the Controls (P = .011–0.034). Patients also reported reduced family satisfaction compared with that of Patient Caregivers (P = .002), which was associated with polytherapy prior to surgery; that is, more drug-resistant seizures. These findings suggested that childhood-onset epilepsy has a lasting effect on family functioning, even when the child has an optimal medical and psychosocial outcome. These initial findings have significant implications for the provision of pre- to postoperative family support in pediatric epilepsy cases.

A versatile hybrid agent-based, particle and partial differential equations method to analyze vascular adaptation

Peripheral arterial occlusive disease is a chronic pathology affecting at least 8–12 million people in the USA, typically treated with a vein graft bypass or through the deployment of a stent in order to restore the physiological circulation. Failure of peripheral endovascular interventions occurs at the intersection of vascular biology, biomechanics, and clinical decision making. It is our hypothesis that the majority of endovascular treatment approaches share the same driving mechanisms and that a deep understanding of the adaptation process is pivotal in order to improve the current outcome of the procedure. The postsurgical adaptation of vein graft bypasses offers the perfect example of how the balance between intimal hyperplasia and wall remodeling determines the failure or the success of the intervention. Accordingly, this work presents a versatile computational model able to capture the feedback loop that describes the interaction between events at cellular/tissue level and mechano-environmental conditions. The work here presented is a generalization and an improvement of a previous work by our group of investigators, where an agent-based model uses a cellular automata principle on a fixed hexagonal grid to reproduce the leading events of the graft’s restenosis. The new hybrid model here presented allows a more realistic simulation both of the biological laws that drive the cellular behavior and of the active role of the membranes that separate the various layers of the vein. The novel feature is to use an immersed boundary implementation of a highly viscous flow to represent SMC motility and matrix reorganization in response to graft adaptation. Our implementation is modular, and this makes us able to choose the right compromise between closeness to the physiological reality and complexity of the model. The focus of this paper is to offer a new modular implementation that combines the best features of an agent-based model, continuum mechanics, and particle-tracking methods to cope with the multiscale nature of the adaptation phenomena. This hybrid method allows us to quickly test various hypotheses with a particular attention to cellular motility, a process that we demonstrated should be driven by mechanical homeostasis in order to maintain the right balance between cells and extracellular matrix in order to reproduce a distribution similar to histological experimental data from vein grafts.

Three-dimensional regional displacement after surgical-orthodontic correction of Class III malocclusion.

To investigate how displacements of maxillo-mandibular structures are associated with each other at splint removal and 1 year post-surgery following 1-jaw and 2-jaw surgeries for correction of Class III malocclusion. Fifty patients who underwent surgical correction with maxillary advancement only (n = 25) or combined with mandibular setback (n = 25) were prospectively enrolled in this study. Cone-beam computed tomographies were taken pre-surgery, at splint removal and at 1 year post-surgery. Three-dimensional cranial base superimpositions and shape correspondence were used to measure the outcomes from pre-surgery to splint removal (surgical changes) and splint removal to 1 year post-surgery (post-surgical adaptations). Pearson's correlation coefficients were used to evaluate the association between the regional displacements. Both surgery groups presented mandibular clockwise rotation with surgery and post-surgical adaptive counterclockwise rotation. In patients treated with maxillary advancement only, the surgical changes of the maxilla were significantly correlated with chin changes. The amount and direction of chin autorotation were significantly correlated with right and left ramus autorotation. Right and left condylar displacements were significantly correlated. One year post-surgery, adaptive displacements and bone remodeling of both rami were correlated with the chin and condylar changes. For the 2-jaw group, the few correlations between the positional and remodeling changes in the anatomic regions of interest observed due to the surgery were different than those observed after post-surgical adaptations, suggesting that these changes occurred independently. Our results indicate that surgical displacements and post-surgical adaptations are often correlated in one-jaw surgery and are, in general, independent in two-jaw surgery.

Outcomes of dogs undergoing limb amputation, owner satisfaction with limb amputation procedures, and owner perceptions regarding postsurgical adaptation: 64 cases (2005-2012).

To evaluate outcomes of dogs and owner satisfaction and perception of their dogs' adaptation following amputation of a thoracic or pelvic limb. Retrospective case series. 64 client-owned dogs. Procedures-Medical records of dogs that underwent limb amputation at a veterinary teaching hospital between 2005 and 2012 were reviewed. Signalment, body weight, and body condition scores at the time of amputation, dates of amputation and discharge from the hospital, whether a thoracic or pelvic limb was amputated, and reason for amputation were recorded. Histologic diagnosis and date of death were recorded if applicable. Owners were interviewed by telephone about their experience and interpretation of the dog's adaptation after surgery. Associations between perioperative variables and postoperative quality of life scores were investigated. 58 of 64 (91%) owners perceived no change in their dog's attitude after amputation; 56 (88%) reported complete or nearly complete return to preamputation quality of life, 50 (78%) indicated the dog's recovery and adaptation were better than expected, and 47 (73%) reported no change in the dog's recreational activities. Body condition scores and body weight at the time of amputation were negatively correlated with quality of life scores after surgery. Taking all factors into account, most (55/64 [86%]) respondents reported they would make the same decision regarding amputation again, and 4 (6%) indicated they would not; 5 (8%) were unsure. This information may aid veterinarians in educating clients about adaptation potential of dogs following limb amputation and the need for postoperative weight control in such patients.

Patients' experiences after bariatric surgery: a qualitative study at 12-month follow-up.

This study used a qualitative approach to understand patients' experiences in post-surgery adaptation related to bariatric surgery, 12 months after this procedure. The study population included 30 obese adults, with a mean age of 40.17 years, who were interviewed 12 months after bariatric surgery. Individual interviews, using open-ended questions, were audiotaped, transcribed and coded according to the grounded theory methodology. The data showed that the subjects described themselves as belonging to one of two opposite and separate groups: success or failure. In both groups, two core categories emerged from the data: outcomes and treatment. Previous expectations were reached by the patients who described themselves as successful, with some remaining concerns related to future weight maintenance and aesthetics issues. The failure group emphasized their unmet expectations and the expectancy that surgery would change their lives remained. Treatment in the successful cases integrated lifestyle changes and bariatric surgery, highlighting the personal commitment required to achieve the objectives. The failure group emphasized bariatric surgery without personal commitment, and healthy eating behaviour was understood as a sacrifice. The post-surgical adaptation experiences were diverse: the cases that were described as a success highlighted lifestyle changes, personal efforts and commitment with the global treatment process. External understanding and the desire for a miracle surgery characterized the cases described as a failure. According to these results, it is necessary to promote adequate information about the whole process and skills required to ensure commitment in all treatment dimensions.

One-year assessment of surgical outcomes in Class III patients using cone beam computed tomography

The purpose of this study was to apply a novel method to evaluate surgical outcomes at 1 year after orthognathic surgery for Class III patients undergoing two different surgical protocols. Fifty patients divided equally into two groups (maxillary advancement only and combined with mandibular setback) had cone beam computed tomography (CBCT) scans taken pre-surgery, at splint removal, and at 1-year post-surgery. An automatic cranial base superimposition method was used to register, and shape correspondence was applied to assess, the overall changes between pre-surgery and splint removal (surgical changes) and between splint removal and 1-year post-surgery at the end of orthodontic treatment (post-surgical adaptations). Post-surgical maxillary adaptations were exactly the same for both groups, with 52% of the patients having changes >2mm. Approximately half of the post-surgical changes in the maxilla for both groups were vertical. The two-jaw group showed significantly greater surgical and post-surgical changes in the ramus, chin, and most of the condylar surfaces (P<0.05). Post-surgical adaptation on the anterior part of the chin was also more significant in the two-jaw group (P<0.05). Regardless of the type of surgery, marked post-surgical adaptations were observed in the regions evaluated, which explain the adequate maxillary–mandibular relationship at 1-year post-surgery on average, with individual variability.

Eph-B4 prevents venous adaptive remodeling in the adult arterial environment.

Eph-B4 determines mammalian venous differentiation in the embryo but is thought to be a quiescent marker of adult veins. We have previously shown that surgical transposition of a vein into the arterial environment is characterized by loss of venous identity, as indicated by the loss of Eph-B4, and intimal thickening. We used a mouse model of vein graft implantation to test the hypothesis that Eph-B4 is a critical determinant of venous wall thickness during postsurgical adaptation to the arterial environment. We show that stimulation of Eph-B4 signaling, either via ligand stimulation or expression of a constitutively active Eph-B4, inhibits venous wall thickening and preserves venous identity; conversely, reduction of Eph-B4 signaling is associated with increased venous wall thickness. Stimulated Eph-B4 associates with caveolin-1 (Cav-1); loss of Cav-1 or Eph-B4 kinase function abolishes inhibition of vein graft thickening. These results show that Eph-B4 is active in adult veins and regulates venous remodeling. Eph-B4-Cav-1-mediated vessel remodeling may be a venous-specific adaptive mechanism. Controlled stimulation of embryonic signaling pathways such as Eph-B4 may be a novel strategy to manipulate venous wall remodeling in adults.

Soft tissue response to mandibular advancement using 3D CBCT scanning

This prospective longitudinal study assessed the 3D soft tissue changes following mandibular advancement surgery. Cranial base registration was performed for superimposition of virtual models built from cone beam computed tomography (CBCT) volumes. Displacements at the soft and hard tissue chin (n = 20), lower incisors and lower lip (n = 21) were computed for presurgery to splint removal (4-6-week surgical outcome), presurgery to 1 year postsurgery (1-year surgical outcome), and splint removal to 1 year postsurgery (postsurgical adaptation). Qualitative evaluations of color maps illustrated the surgical changes and postsurgical adaptations, but only the lower lip showed statistically significant postsurgical adaptations. Soft and hard tissue chin changes were significantly correlated for each of the intervals evaluated: presurgery to splint removal (r = 0.92), presurgery to 1 year postsurgery (r = 0.86), and splint removal to 1 year postsurgery (r = 0.77). A statistically significant correlation between lower incisor and lower lip was found only between presurgery and 1 year postsurgery (r = 0.55). At 1 year after surgery, 31% of the lower lip changes were explained by changes in the lower incisor position while 73% of the soft tissue chin changes were explained by the hard chin. This study suggests that 3D soft tissue response to mandibular advancement surgery is markedly variable.

Three-dimensional assessment of mandibular advancement 1 year after surgery

<h3>Introduction</h3> This prospective observational study evaluated changes in the 3-dimensional position and remodeling of the mandibular rami, condyles, and chin at splint removal and 1 year after mandibular advancement surgery. <h3>Methods</h3> Presurgery, splint removal (4–6 weeks postsurgery), and 1-year postsurgery cone-beam computed tomography scans of 27 subjects were used. Superimposition on the cranial base was used to assess positional or remodeling changes in the anatomic regions of interest. Surface distance displacements were visually displayed and quantified by 3-dimensional color maps. A 1-sample <i>t</i> test was used to assess the average postsurgical changes of each region of interest. The level of significance was set at 0.05. <h3>Results</h3> After antero–inferior chin displacement with surgery (mean, 6.81 ± 3.2 mm at splint removal), the average 1-year postsurgery displacement was not statistically significant (<i>P</i> = 0.44). Postsurgical adaptations greater than 2 mm were observed in 48% of the patients: 16% with an additional anterior–inferior displacement of the chin of 2 to 4 mm, and 4% with ≥4 mm; 20% had postero-superior movement of 2 to 4 mm, and 8% had postero-superior movement of ≥4 mm. The condyles tended to move, on average, ≤2 mm supero-posteriorly with surgery, and this small positional displacement was maintained 1 year postsurgery (right condyle, <i>P</i> = 0.58; left, <i>P</i> = 0.88). The rami exhibited outward (lateral) movements with surgery, with greater displacement of the inferior part of the rami (≥2 mm in 65% of the subjects). This torque of the ramus with surgery was stable 1 year postsurgery. <h3>Conclusions</h3> Three-dimensional assessment of skeletal changes with mandibular advancement surgery shows that nearly half of the patients have >2 mm change in chin position from splint removal to the 1-year follow-up, with approximately equal chances of anterior and posterior movement. Torque of the rami usually occurs with mandibular advancement surgery.

Editor's Comment and Q&A: Three-dimensional assessment of mandibular advancement 1 year after surgery

This prospective observational study evaluated changes in the 3-dimensional position and remodeling of the mandibular rami, condyles, and chin at splint removal and 1 year after mandibular advancement surgery.Presurgery, splint removal (4-6 weeks postsurgery), and 1-year postsurgery cone-beam computed tomography scans of 27 subjects were used. Superimposition on the cranial base was used to assess positional or remodeling changes in the anatomic regions of interest. Surface distance displacements were visually displayed and quantified by 3-dimensional color maps. A 1-sample t test was used to assess the average postsurgical changes of each region of interest. The level of significance was set at 0.05.After antero-inferior chin displacement with surgery (mean, 6.81 +/- 3.2 mm at splint removal), the average 1-year postsurgery displacement was not statistically significant (P = 0.44). Postsurgical adaptations greater than 2 mm were observed in 48% of the patients: 16% with an additional anterior-inferior displacement of the chin of 2 to 4 mm, and 4% with >or= 4 mm; 20% had postero-superior movement of 2 to 4 mm, and 8% had postero-superior movement of >or= 4 mm. The condyles tended to move, on average, <or= 2 mm supero-posteriorly with surgery, and this small positional displacement was maintained 1 year postsurgery (right condyle, P = 0.58; left, P = 0.88). The rami exhibited outward (lateral) movements with surgery, with greater displacement of the inferior part of the rami (2 mm in 65% of the subjects). This torque of the ramus with surgery was stable 1 year postsurgery.Three-dimensional assessment of skeletal changes with mandibular advancement surgery shows that nearly half of the patients have >2 mm change in chin position from splint removal to the 1-year follow-up, with approximately equal chances of anterior and posterior movement. Torque of the rami usually occurs with mandibular advancement surgery.

Postsurgical adaptations after decreasing facial height in monkeys

Postsurgical adaptations after decreasing facial height in monkeys