Integrated Approaches for Reconstruction of Facial Paralysis.

BACKGROUND: Facial paralysis can affect periorbital muscles, oral competence, and facial expressions with significant facial deformities, which could occur in either children or adults with variable severity, duration, and degree of recovery. OBJECTIVE: The present study was aimed to delineate treatment plans for facial paralysis with different clinical scenarios and to report the results of these patients. METHODS: Patients were grouped according to different presentations as follows: (1) facial paralysis with incomplete recovery; (2) young patients of facial paralysis without recovery; (3) senile patients of facial palsy without recovery; (4) combined facial palsy with mandibular deficiency, vascularized bone reconstruction for mandible with (a) subsequent muscle transfer or (b) simultaneous sling operation or (c) simultaneous facial nerve exploration and cross nerve grafting; (5) palsy of frontal branch of facial nerve; (6) palsy of zygomatic-buccal branch of facial nerve; (7) palsy of marginal mandibular branch of facial nerve; (8) partial recovery with dyskinesia; and (9) facial paralysis with dynamic asymmetry and muscle atrophy. According to clinical scenarios, different treatment plans were provided, and clinical outcomes were evaluated and presented. RESULTS: All patient groups achieved fair or satisfactory outcomes. Revisions using sling procedures, botulinum toxin injection, and filler or fat graft as supplement further refined the ultimate outcomes. CONCLUSIONS: For reconstruction of facial paralysis, individualized integrated treatment plans are mandatory according to the presentation and condition of the patient. Comprehensive considerations and strategic solutions for the existing disabilities have been appreciated by the patients. The least numbers of operations with considerate correction of asymmetry were the major concerns of the patients.

Three salvage strategies in microvascular fibula osteocutaneous flap for mandible reconstruction with vascular compromise and establishment of an algorithm.

BACKGROUND: Fibula osteocutaneous flap is associated with a higher rate of reexploration in mandible reconstruction due to limited space for the fixation of various tissue components on multiple segments of the fibula flap. To maintain optimal circulation to the flap and to prevent negative outcomes because of partial or total flap loss, we shared our experiences on salvaging the free fibula flap with vascular compromise in the first reexploration and we developed an algorithm. METHODS: From 1992 to 2018, 12 patients between the ages of 48 to 63 (mean: 52.5) who had presented with oral squamous cell carcinoma (n = 10) followed by osteoradionecrosis of the mandible (n = 2) were explored. The operative findings were; (1) occlusions of vein (3 cases); (2) occlusions of artery (4 cases); and (3) occlusions of both artery and vein (5 cases). After correcting the kinking or evacuating the hematoma, the arterial inflow was initially reestablished by anterograde flow. If this was nonfunctional, retrograde flow from the distal end of the peroneal artery was provided. For the vein, anterograde venous drainage was reestablished. If the thrombus extended deep into the peroneal vein, regular venous return was blocked on the anterograde side, and the flap remained congested therefore retrograde venous drainage was performed regardless of the valves in the vein. However, the two ends of the peroneal artery were anastomosed to prevent thrombosis of the artery. RESULTS: The success rate of revised cases was 75% (9/12). All failed cases had presented with both artery and vein occlusion (three cases). Pectoralis major musculocutaneous flap and anterolateral thigh flap were needed for the external surface in two cases. Skin graft was required for seven cases to restore intraoral lining. Six patients underwent dental rehabilitation with prosthetic implants. CONCLUSION: Immediate reexploration is mandatory to salvage the flap.

Pharyngoesophageal reconstruction with free jejunum or radial forearm flap as diversionary conduit: Functional outcomes of patients with persistent dysphagia and aspiration.

BACKGROUND: A diversion loop provides an alternative pathway for food intake from the bucco-gingival sulcus into the thoracic esophagus. Therefore, the bolus does not pass via pharynx where choking may occur in case of severe dysphagia. The data about outcomes and complications of the diversionary procedure are short and they refer to small cohort with brief follow-up. METHODS: This retrospective study analyzed data of 48 patients, mean aged 34.3 years (range, 22-58 years), undergoing the creation of a diversion loop in two stages. Patients complained of aspiration, choking, and dysphagia. Swallowing disorders were caused by corrosive injury, radiation damage, or neurologic injury, and were investigated through laryngoscopy and esophagography. A diversion loop was created in 45 cases with free jejunal flap and in 3 cases with radial forearm flap. Complications, functional outcomes, and revision rate were reviewed. The mean follow-up was 26.3 months. RESULTS: We reported one failure (2%) and one partial necrosis of the free flaps. The most frequent complication was hematoma (8%). One case of esophagocutaneous fistula (2%) and two cases of stricture (4%) were also observed. Forty-two patients (87%) took all of the daily diet from their mouths through the diversionary conduit. A poor functional outcome was significantly associated with pre-operative radiotherapy (p < .0001). CONCLUSIONS: The diversion loop offers an alternative route for alimentation. Patients are freed from their choking obsession; moreover, they are rehabilitated into society without the drawbacks of permanent jejunostomy feeding. The technique was upgraded with caudal marginal mandibulectomy to improve the outcomes. Patients undergoing a diversionary procedure due to radiation damage should be carefully informed about the expected functional results.

The Existence of Periodontal Disease and Subsequent Ocular Diseases: A Population-Based Cohort Study.

Background and objectives: We aimed to evaluate the correlation between periodontal disease (PD) and following ocular diseases via the National Health Insurance Research Database in Taiwan. Materials and Methods: A retrospective cohort study was conducted. Subjects were regarded as having PD according to the diagnostic codes. For comparison, each subject with PD was matched to one non-PD individual from the database after exclusion. The main outcome was defined as the development of infectious keratitis, endophthalmitis, orbital cellulitis, lacrimal duct infection, uveitis and infectious scleritis. Cox proportional hazard regression was used to yield the adjusted hazard ratios (aHR) of ocular diseases between the study and control groups. Results: A total of 426,594 subjects were enrolled in both the study and control groups. In the multivariable analysis, significantly higher rates of infectious keratitis (aHR: 1.094, 95% CI: 1.030-1.161), uveitis (aHR: 1.144, 95% CI: 1.074-1.218) and infectious scleritis (aHR: 1.270, 95% CI: 1.114-1.449) were found in the study group. Concerning the PD interval, infectious keratitis (aHR: 1.159, 95% CI: 1.041-1.291) and infectious scleritis (aHR: 1.345, 95% CI: 1.055-1.714) would significantly occur in PD patients with an interval shorter than two years, individuals with a PD interval that ranged from two to five years were under a higher risk of developing uveitis (aHR: 1.184, 95% CI: 1.065-1.315) and infectious scleritis (aHR: 1.386, 95% CI: 1.125-1.708), and the rate of uveitis (aHR: 1.149, 95% CI: 1.038-1.272) was significantly higher if PD persisted more than five years. Conclusions: The presence of PD was moderately associated with the risk of developing infectious keratitis, uveitis and infectious scleritis.

Optimizing survival of large fibula osteocutaneous flaps for extensive full-thickness oromandibular defects: A two-stage approach with temporary orocutaneous fistula.

INTRODUCTION: Composite and large head and neck defects requiring extensive skin-mucosa coverage are often reconstructed by combining flaps. Herein, we present a simple and reliable two-stage fibula osteocutaneous (FOC) flap technique to improve the survival of a large skin paddle for oromandibular reconstructions. METHODS: From October 2011 to September 2016, 47 patients with through-and-through oromandibular defects were reconstructed using FOC flaps with large skin paddles. To ensure optimum survival of skin paddles, temporary orocutaneous fistula were left in place and closed during the second stage operation via de-epithelialization of the skin paddle and suturing of mucosa. Demographic data, operative details, and postoperative complications were recorded. RESULTS: The skin paddle dimensions ranged from 20 to 31.5 cm in length and 12 to 17 cm in width with an average area of 430.4 cm2 (range 300-504). The average time between the two stages and hospital stay were 10 days and 14 days, respectively. Complications at the donor site included wound dehiscence (n = 3, 6.4%), partial skin graft loss (n = 3, 6.4%) and hematoma (n = 2, 4.3%). Recipient site complications included two (4.3%) early postoperative venous congestions that resolved after elevation and three (6.4%) partial skin flap necrosis (less than 5% surface area). All complications resolved with bedside conservative management. There was only one take-back for evacuation of recipient site hematoma (2.1%) but no flap loss. CONCLUSION: Two-staged large skin paddle FOC flaps can simplify reconstruction of extensive oromandibular defects by improving the reliability of the sizable skin paddle and negating the need for a second flap.

The retrograde transverse cervical artery as a recipient vessel for free tissue transfer in complex head and neck reconstruction with a vessel-depleted neck.

BACKGROUND: Reconstruction in a vessel-depleted neck is challenging. The success rates can be markedly decreased because of unavailability of suitable recipient vessels. In order to obtain a reliable flow, recipient vessels away from the zone of fibrosis, radiation, or infection need to be explored. The aim of this report is to present our experience and clinical outcomes using the retrograde flow coming from the distal transverse cervical artery (TCA) as a source for arterial inflow for complex head and neck reconstruction in patients with a vessel-depleted neck. METHODS: Between July 2010 and June 2016, nine patients with a vessel-depleted neck underwent secondary head and neck reconstruction using the retrograde TCA as recipient vessel for microanastomosis. The mean age was 49.6 years (range, 36 to 68 years). All patients had previous bilateral neck dissections and all, except one, had also received radiotherapy. Indications included neck contracture release (n = 3), oral (n = 1), mandibular (n = 3) and pharyngoesophageal (n = 2) reconstruction necessitating free anterolateral thigh (n = 3) and medial sural artery (n = 1) perforator flaps, fibula (n = 3) and ileocolon (n = 2) flaps respectively. RESULTS: There was 100% flap survival rate with no re-exploration or any partial flap loss. One case of intra-operative arterial vasospasm at the anastomotic suture line was managed intra-operatively with vein graft interposition. There were no other complications or donor site morbidity during the follow-up period. CONCLUSIONS: In a vessel-depleted neck, the reverse flow of the TCA may be a reliable option for complex secondary head and neck reconstruction in selected patients.

Optimizing Outcomes following Total and Subtotal Tongue Reconstruction: A Systematic Review of the Contemporary Literature.

Background More than 45,000 Americans are diagnosed with oropharyngeal cancer annually and multimodal treatment often requires wide excision, lymphadenectomy, chemotherapy, and radiation. Total and subtotal lingual resection severely impairs speech, swallow, and quality of life (QoL). This study investigates functional outcomes and QoL following subtotal and total tongue resection with free tissue transfer reconstruction. Materials and Methods A systematic review of the English language literature was performed using PubMed, Ovid, Embase, and Cochrane databases based on predetermined inclusion/exclusion criteria. Included studies were reviewed for surgical technique, adjuvant treatment, surgical and functional outcomes, and QoL. Results From an initial search yield of 1,467 articles, 22 studies were included for final analysis. Speech intelligibility was correlated with the volume and degree of protuberance of the neotongue. Adjuvant therapy (radiation) and large tumor size were associated with worse speech and swallow recovery. At 1 year follow-up, despite 14 to 20% rates of silent aspiration, 82 to 97% of patients resumed oral feeding. Neurotized flaps have been demonstrated to improve flap sensation but have not yet demonstrated any significant impact on speech or swallow recovery. Finally, many patients continue to experience pain after surgery, but patient motivation, family support with physician, and speech therapist follow-up are associated with improved QoL scores. Conclusion Tongue reconstruction is dictated by the amount of soft tissue resection. Taking into consideration the most common factors involved after tongue resection and reconstruction, further studies should focus on more objective measurements to offer solutions and maximize final outcomes.

True functional reconstruction of total or subtotal glossectomy defects using a chimeric anterolateral thigh flap with both sensorial and motor innervation.

BACKGROUND: The purpose of this study was to report the motor functional outcomes and sensory recovery of patients who had undergone total or subtotal glossectomy for oral squamous cell carcinomas reconstructed with chimeric anterolateral thigh (ALT) flaps. METHODS: Six patients, 4 men and 2 women, with a mean age of 49.5 years (range, 36-73 years) were included in the study. All patients were treated with chimeric ALT, including the vastus lateralis muscle with its motor nerve and skin paddle with its innervating nerve. All patients were administered functional tests involving sensory recovery, intelligibility, and swallowing. Flap sensibility was evaluated using light touch sensation with the Semmes-Weinstein monofilament test, 2-point discrimination according to the Weber sensitive test, warm and cold temperature sensations, and pain sensation. Intelligibility was scored by a speech therapist on a scale from 1 to 5. Swallowing was assessed by electromyography, deglutition scores (on a scale of 1 to 8), and modified barium swallow. Donor-site morbidities were recorded. RESULTS: Mean follow-up was 26.6 months (6 months-5 years). The flaps were successful in all 6 patients. The donor site was closed primarily and no complications were seen in the follow-up period. Normal extension of the knee joint and no evidence of lateral patella instability occurred. Speech intelligibility was good (4) in 3 patients and acceptable (3) in 3. Deglutition scores were 6 in 2 patients, 5 in 2, and 4 in 2. Modified barium swallow revealed that 4 patients experienced bolus transit, but 2 required a liquid swallow to promote bolus transit. Electromyographic recordings showed innervations of the vastus lateralis muscle with active generation of motor unit potentials in 4 patients when trying to elevate the tongue. This was not performed in 1 patient, and 1 other had macroscopic muscle contractions. All sensory tests were satisfactory in all parameters. CONCLUSIONS: The results of this reconstructive option were satisfactory in terms of motor function and sensitive assessment of the neotongue. This technique is strongly recommended for patients with total or subtotal glossectomy.

Reconstruction for osteoradionecrosis of the mandible: superiority of free iliac bone flap to fibula flap in postoperative infection and healing.

BACKGROUND: Osteoradionecrosis (ORN) of the mandible is not an uncommon complication after radiotherapy for head and neck cancers. Although definitive treatment has been confirmed as radical excision of the necrotic bone with simultaneous vascularized osteocutaneous flap reconstruction, it remains a unique challenge. In this study, we compare our results of reconstruction with free iliac and fibula flaps in flap survival, bony union, and postoperative complications. PATIENTS AND METHODS: From 1986 to 2011, there were 153 mandibular ORN cases in our center that were treated with radical resection of the necrotic bone and reconstruction with either vascularized iliac (n=108) or fibula flaps (n=45). Data collected for analysis included patient demographics, flap survival rate, postoperative infection rate, nonunion/malunion rate, mean hospital stay, and antibiotics use. RESULTS: All patients healed eventually without recurrence of ORN. However, we observed difference in the complication rate between the iliac flap group and fibula flap group. In the group with iliac flap reconstruction, patients required less days of hospital stay for intravenous antibiotics treatment postoperatively. The average days required for intravenous antibiotics in the iliac flap group were 10.46 (2.28) versus 16.09 (3.88) days in the fibula group (P<0.01). In the group with fibula flap reconstruction, 9 (20.0%) patients had subsequent neck infection due to healing problem, compared to 8 (7.4%) patients in the iliac flap group (P=0.04). In the iliac flap group, the nonunion and malunion rates were 4.6% and 2.8% respectively; whereas in the fibula group, the rates were 15.5% and 6.6%, respectively (P=0.04 and 0.36, respectively). CONCLUSIONS: For ORN patients, vascularized iliac bone flap provides more reliable results compared to fibula flap. The merits of vascularized iliac flap include the following: (1) its natural curve mimics the shape of mandible and does not need osteotomy; (2) it offers more volume of bone that matches better to the native mandible to allow later osteointegration as well as faster bony union, due to the nature of being a membranous bone; and (3) it carries more abundant soft tissue to obliterate possible dead space. The only disadvantages are short pedicle and requiring special management of skin paddle, which can be overcome by training in microsurgery.

Morphological and morphometric evaluation of the ilium, fibula, and scapula bones for oral and maxillofacial reconstruction.

This study aimed to evaluate the osteometric boundaries of the ilium, fibula, and scapula beyond which reconstruction of oromandibular and craniofacial defects, using these free flaps, may not be optimal. Fibula, scapula, and iliac bones were obtained bilaterally from 33 female and 27 male European adult cadavers (n = 60). Adapting classical anthropometric methods to surgical needs by modifying the measuring bone localizations and measurement points, a measuring system of osteometry and morphometry was used, to quantify the usable bone length of the iliac crest, fibula, and lateral border of the scapula and to localize an oval region (OR) in the ilium. The thin, translucent OR of ilium was localized 62.4 ± 5.6 mm posterior to the maximum concavity between the anterior superior (ASIS) and anterior inferior iliac spine and 26.7 ± 6 mm caudal to the intermediate line of the iliac crest. The available iliac crest was measured from ASIS to the posterior superior iliac spine (PSIS) 247.5 ± 12.6 mm, fibula supplied 170.2 ± 19.1 mm harvestable bone, and the lateral border of the scapula 94.3 ± 8.5 mm [Corrected]. The OR influenced the harvestable bone shape and volume of the ilium. Measuring of the localization points of OR, we found that the size of the OR was very variable and that the height of the neomandible reconstructed with iliac crest might alter with aging. Our findings contribute with knowledge of detailed morphometric measurements on commonly used donor bones to the planning strategies of volumetric defects in oral and maxillofacial region by precise osteometric localization method of OR and relativized length measurements.

Latissimus dorsi-rib pedicle flap for mandibular reconstruction as a salvage procedure for failed free fibula flap.

BACKGROUND: Mandibular reconstruction is usually performed by using free vascular flaps. However, there are instances in which it must be carried out with pedicle flaps. Insofar, the main option recommended is the pectoralis major (PM) + rib pedicle flap. METHODS: A 45-year-old patient affected by a primitive mandibular tumor presented after an unsuccessful reconstruction with free fibula flaps. He refused a PM + rib pedicle reconstruction, while he accepted to undergo a latissimus dorsi (LD) + rib flap reconstruction. RESULTS: The postoperative course was uneventful. Also, the range of movements of the upper limb involved in the operation showed no significant changes after surgery. CONCLUSIONS: The LD + rib flap proved to be a useful alternative procedure for mandibular reconstruction after cancer ablation in patients who are not candidates for vascularized bone-containing free flaps and refuse the PM + rib flap reconstruction.

Sleep and its association with dental caries or myopia in first graders.

AIM: First grade is a transition from pre-school to school-age. The change in lifestyle behaviours such as sleep may have a physiological response, which contributes to the presence or absence of two highly incident diseases: dental caries or myopia. The aim of the study was to examine the association between sleep and myopia as well as sleep and dental caries in first graders. DESIGN: It is a cross-sectional study. METHODS: This was a recruitment phase of an interventional study. A total of 338 children whose caregivers completed a Children's Sleep Habits Questionnaire. Caregivers also provided information regarding myopia and caries status of children and their parents. Binary logistic regression was applied to analyse the potential risk factors. RESULTS: Dental caries and myopia rates were 45.9% and 9.5%, respectively. After adjusting for children's gender, children's age, fathers with caries and mothers with caries, the odds ratio for dental caries in children who slept less than 9 h when compared to those who slept for nine and more hours was 1.94. Mothers with caries were 3.37 times more likely to have children with caries than mothers without caries. However, sleep was not associated with myopia in first graders. CONCLUSION: Sleeping less than 9 h and maternal caries were risk factors of children developing dental caries. Future sleep and myopia studies can be conducted on higher graders who may present prolonged exposure and accumulations of myopic risk factors. IMPLICATIONS: Screening of children with insufficient sleep is needed for nurses to enable the early identification of high-risk groups for dental caries in school settings. Family nurses are encouraged to work with family members to implement tailored sleep interventions, in order to facilitate better sleep and oral health practices in both school and home settings. REGISTRATION: This study protocol was registered on ClinicalTrials.gov (Registration number: Redacted).

The treatment of composite defect of bone and soft tissues with a combined latissimus dorsi and serratus anterior and rib free flap.

BACKGROUND: Composite defects of bone and soft tissues represent a reconstructive challenge. Several techniques have been described in the medical literature; however, extensive composite defects should be reconstructed with microvascular free tissue transfer. The purpose of this report is to present the use of a composite latissimus dorsi and serratus anterior and rib free flap (LD-SA/rib) as an alternative procedure in patients who cannot undergo more commonly used vascularized bone-containing free flap reconstruction. METHODS: Since January 2009, 12 patients have undergone bone and soft tissues reconstruction with a composite LD-SA/rib flap. In this case series, indications for LD-SA/rib reconstruction were large mandibular defects after oral cancer ablation, scalp defects, and lower extremity defects. RESULTS: All flaps survived entirely. With reference to postoperative complications, haematoma occurred in four patients, scar contractures in three cases, lower lip incontinence in one patient, and local infection in one patient. Skin graft revision was performed in two cases and secondary debulking procedure in three patients. Flap viability was consistent during the 2-year follow-up. CONCLUSIONS: LD-SA/rib free flap should be regarded as an effective procedure for reconstruction of composite tissue defects in patients who are not candidates for more commonly used vascularized bone-containing free flaps.

Free fibular flap with periosteal excess for mandibular reconstruction.

BACKGROUND: In microvascular transfer of fibular osteocutaneous flap for mandible reconstruction after cancer ablation, good bone union is necessary to allow timely radiation therapy after surgery. As the area of bone contact between fibula and the original mandible at the edge of the mandibular defect is small, a periosteal excess at both ends of the fibula covering the bone junction can be used to increase the chance of bone union. The purpose of this study is to investigate whether a periosteal excess surrounding both ends of the fibula flap can provide better blood supply and, therefore, ensure bone union and wound healing at 6 weeks after surgery and before radiation therapy initiation. PATIENTS AND METHODS: The transfer of fibular osteocutaneous flap with periosteal excess was only applied to reconstruct segmental mandibular defects. As a consequence, only cases in which osteotomy of fibula was not performed were included in this study. A total of 34 fibular flaps without osteotomies were performed between 2000 and 2008; 17 with and 17 without the periosteal excess. The bone union was evaluated in terms of osseous callus formation using X-rays and CT three-dimensional images at 6 weeks after surgery, and results were assessed by three independent radiologists. RESULTS: There was a significant difference between reconstructions with and without the periosteal excess in terms of bone union (P = 0.022). With reference to postoperative complications, the group reconstructed without periosteal excess presented a higher number of complications, mainly consisting of partial and total flap necrosis, respectively six (35.29%) and two (11.76%) cases. In the group reconstructed with periosteal excess, no loss of the skin island has occurred. A significant difference was observed in terms of partial flap necrosis (P = 0.024), while the other complications did not reveal a statistically significant difference (P > 0.05). CONCLUSIONS: The use of a periosteal excess at both ends of the fibula flap provides better blood supply and is, therefore, able to ensure good bone healing and skin paddle survival regardless of the radiotherapy.

Oxidation-mediated scaffold engineering of hyaluronic acid-based microcarriers enhances corneal stromal regeneration.

The functional design of scaffolding biomaterials with potent capabilities of promoting cell adhesion and proliferation is critically important for tissue repair and regeneration. Here, we exploit the effects of oxidation level of aldehyde hyaluronic acid (oHA) on gelatin microcarriers for repairing corneal injuries. Specifically, high oxidation levels can endow the microcarrier surface with large oHA grafting amount, smooth topography, and strong stiffness, consequently formulating biocompatible scaffolding materials with superior affinities for keratocyte attachment and growth. In a rabbit model of corneal alkali burn injury, single intracorneal injection of keratocytes/functionalized microcarriers with an appropriate oxidation level could effectively reduce corneal swelling (~62-fold improvement), recover ~94% collagen production and ~89% keratocan expression, and repair disordered collagenous stromal architecture after 4 weeks. These findings on the oxidation level effects of the aldehyde polysaccharide show a great potential use in the development of advanced scaffolds for efficient tissue engineering.

The occlusion-adjusted prefabricated 3D mirror image templates by computer simulation: the image-guided navigation system application in difficult cases of head and neck reconstruction.

Computer applications in head and neck reconstruction are rapidly emerging and create not only a virtual environment for presurgical planning, but also help in image-guided navigational surgery. This study evaluates the use of prefabricated 3-dimensional (3D) mirror image templates made by computer-simulated adjusted occlusions to assist in microvascular prefabricated flap insertion during reconstructive surgery. Five patients underwent tumor ablation surgery in 1999 and survived for 8 years. Four of the patients with malignancy received radiation therapy. All patients in this study suffered from severe malocclusion causing trismus, headache, temporomandibular joint pain, an unsymmetrical face, and the inability of further osseointegrated teeth insertion. They underwent a 3D computer tomography examination and the nonprocessed raw data were sent for computer simulation in adjusting occlusion; thus, a mirror image template could be fabricated for microsurgical flap guidance. The computer simulated occlusion was acceptable and facial symmetry obtained. The use of the template resulted in a shorter operation time and recovery was as expected. The computer-simulated occlusion-adjusted 3D mirror image templates aid in the use of free vascularized bone flaps for restoring continuity to the mandible. The coordinated arch will help with further osseointegration teeth insertion.

Effect of deacetylation degree on controlled pilocarpine release from injectable chitosan-g-poly(N-isopropylacrylamide) carriers.

Development of biodegradable thermogels as intracameral injectable carriers for ocular delivery of antiglaucoma medications can provide a better treatment modality with low dosing frequency than eye drop formulations. For the first time, this study investigates the effect of deacetylation degree (DD) of the polysaccharide component in chitosan-g-poly(N-isopropylacrylamide) (CN) carriers on controlled release of pilocarpine in the management of glaucoma. Our results showed that increasing the chitosan DD from 60.7% to 98.5% leads to enhanced biodegradation resistance of carrier and prolonged release profile of the drug. Significant DNA damage and caspase-3 activation could be detected in lens epithelial cell cultures exposed to CN made from highly deacetylated polysaccharides, indicating apoptosis-related cytotoxicity due to relatively high positive charge density of the graft copolymers. Postoperative outcomes demonstrated that long-term therapeutic efficacy in glaucomatous rabbits is governed by intraocular pressure changes in response to intracamerally administered pilocarpine-loaded CN, strongly suggesting the usefulness of deacetylation in this injectable drug delivery carrier.

Combined anterolateral thigh flap and vascularized fibula osteoseptocutaneous flap in reconstruction of extensive composite mandibular defects.

Extensive composite defects of the oromandibular area are usually created after the surgical treatment of T3 and T4 cancers, requiring complex reconstructive plastic surgical procedures. The preferred treatment method for this type of defect is reconstruction with two free flaps. The use of the vascularized fibula osteoseptocutaneous flap for the bone and inner lining defect is well known and accepted. Among the flaps that can be used for the outer lining and soft-tissue reconstruction, the two most commonly used have been the forearm flap and the rectus abdominis myocutaneous flap. However, these flaps have some disadvantages that restrict their use for this purpose. The forearm flap is usually too thin to cover the fibular bone and reconstruction plate, and the rectus abdominis myocutaneous flap can cause a subclinical reduction in abdominal strength. Both radial forearm and rectus abdominis myocutaneous flaps are difficult to harvest during tumor excision. Because of these drawbacks, over the past several years the authors have preferred to use the anterolateral thigh flap for outer face, neck, and submandibular region reconstructions. From October of 1998 to June of 2000, 22 extensive composite mandibular defect reconstructions using the free anterolateral thigh flap, combined with the vascularized free fibula osteoseptocutaneous flap, were performed at the Chang Gung Memorial Hospital. Complete flap survival was 90.9 percent (40 of 44 flaps). Complete loss was seen in an anterolateral thigh flap, which was then reconstructed with a pectoralis major myocutaneous pedicled flap (2.3 percent). There were five venous problems: three in osteoseptocutaneous free fibula flaps, the other two in anterolateral thigh flaps; all were revised immediately. However, the skin islands of two osteoseptocutaneous free fibula flaps and one anterolateral thigh flap developed partial necrosis (6.8 percent). The other complications were compartment syndrome in the leg in one patient, external carotid artery rupture in one patient, three donor-site infections in two patients, three neck wound infections, and one myocardial insufficiency; all were treated properly. Thirteen patients underwent revision procedures 6 months after the first operation. These procedures included debulking of the flap or revision of the mouth angle or both. Trismus or intraoral contraction was noted in none of these patients. In conclusion, the free anterolateral thigh flap combined with the vascularized fibula osteoseptocutaneous flap seems to be a good choice in the reconstruction of the extensive composite defects of the oromandibular region aesthetically and functionally.

Osteoradionecrosis of the mandible after oromandibular cancer surgery.

Although postoperative radiotherapy has proved effective in improving local control and survival in patients with head and neck cancers, its complications, especially mandibular osteoradionecrosis, reduce the quality of life. Mandibular surgery before the radiotherapy adds an additional risk factor for osteoradionecrosis. This study reviews patients in Chang Gung Memorial Hospital, Taipei, Taiwan, over a 10-year period, who underwent intraoral cancer resection followed by postoperative radiotherapy and thereafter developed osteoradionecrosis of the mandible. A total of 24 men and three women with a mean age of 49.9 years were identified and included in the study. In 10 cases, tumor resection was performed with a marginal mandibulectomy; in eight cases, tumor resection was performed after mandibular osteotomy; and in three cases, a segmental mandibulectomy was performed, and the defect was reconstructed with a fibula osteoseptocutaneous flap. In six cases, tumor excisions were performed without interfering with the mandibular continuity. Patients received postoperative external beam radiotherapy into the primary site and the neck, with a mean dose (+/-SD) of 5900 +/- 1300 cGy in an average of 35 fractions during an average of 6.5 weeks. The average elapsed time between the end of radiation therapy and clinical diagnosis of osteoradionecrosis of the mandible was 11.2 months (range, 2 to 36 months). The time elapse between the end of the radiation therapy and the diagnosis of osteoradionecrosis was influenced by initial treatment (Kruskal-Wallis test: n = 27, chi-square = 12.884, p < 0.005), and this period was shorter if the mandibular osteotomy or marginal mandibulectomy was performed (the two lowest mean ranks in the test). However, if the initial surgery resulted in a segmental mandibulectomy reconstructed with a fibula osteoseptocutaneous flap, onset of the osteoradionecrosis was relatively late (Kruskal-Wallis test: n = 21, chi-square = 7.731, p = 0.052). After resection of osteoradionecrotic bone and surrounding soft tissue, 22 patients underwent reconstructive procedures with a fibula osteoseptocutaneous flap, and five patients underwent reconstructive procedures with an inferior genicular artery osteoperiosteal cutaneous flap. One fibula osteoseptocutaneous flap showed total failure and another showed a 25 percent skin loss; both were revised with pedicled flaps. The skin paddle of an inferior genicular artery flap was replaced with an anterolateral thigh flap because of anatomic variation of the skin vessel. Once the diagnosis of osteoradionecrosis is established, replacement of the dead bone and surrounding tissue with a vascularized free bone flap is inevitable, and a composite osteocutaneous free flap is a good option.

Bowel preparation before microvascular free colon transfer for head and neck reconstruction: is it necessary?

Mechanical bowel preparation before any intestinal operation, especially when the large intestine is involved, is routine practice for most surgeons. This practice has been questioned by many colorectal surgeons, with convincing data showing the lack of benefit of preoperative mechanical bowel preparation. Free microvascular transfer of the large intestine is occasionally performed for reconstruction of the upper esophagus, as it provides a better size match for the oropharynx than other visceral organs. Nine patients underwent reconstruction of the cervical esophagus and voice tube using a segment of ileocolon. In all patients, the cervical esophagus was reconstructed using the ascending colon and the voice tube was reconstructed using the ileal segment. Both were transferred as one free flap. All patients underwent the procedure without any form of preoperative mechanical bowel preparation. The patients were able to tolerate a solid diet at the end of the mean follow-up period of 7 months, and all esophagograms showed no evidence of stricture formation. One patient developed a fistula at the recipient site that was treated with a regional flap, one patient developed a superficial wound infection of the abdominal wall, and one patient developed a postoperative abdominal wound dehiscence after several episodes of excessive coughing. Microvascular transfer of a large intestinal segment without preoperative mechanical bowel preparation for the reconstruction of the esophagus is a safe procedure. It can avoid the discomfort and complications associated with mechanical bowel preparation. If preoperative mechanical bowel preparation is preferred, the results of this study, which are based on nine patients, demonstrate the safety of this practice in cases where the patient did not follow proper instructions or in cases where the use of the colon was not anticipated preoperatively.