Factors influencing CAD/CAM accuracy in fibula free flap mandibular reconstruction

La tecnologia CAD/CAM (Computer-Aided Design/Computer-Aided Manufacturing) ha migliorato sia i risultati funzionali che morfologici nella chirurgia ricostruttiva mandibolare. L\u2019obiettivo del nostro studio \ue8 stato quello di valutare questo tipo di tecnologia ed i fattori che possono influenzare la sua precisione. Un totale di 26 casi di ricostruzione mandibolare con lembo libero di fibula, utilizzando tecnologia CAD/CAM sono stati operati presso l\u2019Unit\ue0 Maxillofacciale della Fondazione IRCCS Ca\u2019 Granda Ospedale Maggiore Policlinico di Milano, da giugno 2014 a febbraio 2018. Abbiamo valutato l\u2019accuratezza confrontando i files STL di pianificazione chirurgica virtuale (obiettivo pianificato) con il file STL di una scansione TC postoperatoria precoce (risultato postoperatorio ottenuto). Entrambi i file STL sono stati importati su Geomagic Studio 2016 (Geomagic Gmbh). In base alla posizione della placca di ricostruzione (punto di riferimento fisso), abbiamo confrontato la deviazione sul condilo sinistro, gonion sinistro, gnathion, gonion destro e condilo destro, per calcolare l\u2019errore medio di deviazione. L\u2019errore medio di deviazione varia da 0,6 mm a 2,2 mm. Solo 2 dei 26 casi analizzati avevano un errore medio uguale o superiore a 2 mm (7,7%). L\u2019area mediana (symphysis-gnathion) ha mostrato una variazione pi\uf9 bassa (1,05 \ub1 0,92 mm) mentre l\u2019area di gonion ha mostrato maggiore variazione (la variazione media del gonion destro e sinistro era rispettivamente di 1,6 mm e 1,46 mm). Nessuno dei possibili fattori (tempi di ricostruzione, malignit\ue0 o benignit\ue0, sito o dimensione del difetto) che potrebbero influenzare la precisione del CAD/CAM, ha mostrato un\u2019influenza significativa. La tecnologia CAD/CAM nella ricostruzione microvascolare dei difetti mandibolari mediante lembo libero di fibula minimizza gli errori umani ed \ue8 considerato come un intervento chirurgico indipendente dall\u2019operatore con alto grado di accuratezza e riproducibilit\ue0.Computer-aided design/computer-aided manufacturing (CAD/CAM) technology has im-proved the functional and morphological results of mandibular reconstructive surgery. The purpose of this study was to objectively assess this technology and factors affecting its accuracy.Fibula free flap mandibular reconstruction was performed in 26 cases us-ing CAD/CAM technology at the Maxillofacial Unit of Fondazione IRCCS Ca\u2019 Gran-da Ospedale Maggiore Policlinico, Milan, between June 2014 and February 2018. We evaluated the technology\u2019s accuracy by comparing the virtual surgical planning STL file (planned-target mesh) with the STL file from an early postoperative CT scan (postopera-tive-achievement mesh) in each case. The STL files were imported into Geomagic Studio 2016 (Geomagic GmbH). According to the position of the reconstruction plate (fixed reference point), we assessed deviations at the right condyle, right gonion, gnathion, left gonion and left condyle, calculating mean, minimum and maximum error values.Mean error values ranged from 0.6 to 2.2 mm; they were 65 2 mm in only 2 (7.7%) cases. The midline area (symphysis-gnathion) showed the least variation (1.05 \ub1 0.92 mm), and the gonion area showed the greatest variation (right and left means of 1.6 and 1.46 mm, respectively). Among all possible factors that could affect CADCAM accuracy, nothing showed significant influence, including the timing of reconstruction, site and size of the defect and malignancy status. CAD/CAM technology has a high degree of accuracy and reproducibility for microvascular reconstruction of mandibular defects using fibula free flaps, regardless of the defect site and length, use of a single- or double-barrel graft or timing of reconstructio

Free flap loss caused by heparin-induced thrombocytopenia and thrombosis (HITT) : a case report and literature review = Trombocitopenia eparino-indotta e trombosi (HITT): Una causa sottostimata di fallimento di lembi liberi : Case report e revisione della letteratura

Heparin-induced thrombocytopenia and thrombosis (HITT) represents a dramatic condition that is difficult to diagnose because of nuanced clinical presentation. Therefore, in every case of microvascular thrombosis during heparin-therapy prompt suspicion about HITT is necessary to avoid flap necrosis. We present a case of HITT which, as the 8 other articles reviewed, clearly shows that HITT is difficult to diagnose and complex to manage. Microvascular reconstruction is the first choice in head and neck reconstruction; unfortunately, dramatic outcomes in free flap surgery due to unpredictable thrombotic events are still reported in the English literature. More knowledge is required about HITT and reaching a consensus about thrombotic prevention in microsurgery could be helpful. Furthermore, a careful anamnesis can help minimise unexpected situations

Free flap loss caused by heparin-induced thrombocytopenia and thrombosis (HITT): a case report and literature review

La trombocitopenia eparino-indotta con trombosi rappresenta una complicanza che può portare a esiti drammatici nella chirurgia ricostruttiva microvascolare, tanto più che il suo riconoscimento non è sempre semplice. In ogni caso di trombosi microvascolare, in corso di terapia eparinica, il sospetto di HITT deve subito insorgere, così da poter intercettare e trattare la catena di eventi che porterebbe alla necrosi del lembo ricostruttivo. Presentiamo un caso che dimostra quanto possa essere difficile la diagnosi di HITT, così come appare negli altri reports reperibili in letteratura internazionale. I lembi microvascolari sono il gold standard nella chirurgia ricostruttiva cervico-facciale: purtroppo però il successo della metodica può essere inficiato da eventi trombo-embolici imprevedibili. Crediamo che una maggior divulgazione e la formulazione di domande anamnestiche specifiche possano essere utili nel limitare le conseguenze devastanti della HITT

Analysis of recurrences in 322 TIS, T1, or T2 glottic carcinomas treated by carbon dioxide laser

An endoscopic approach to early glottic carcinoma is considered a sound treatment for both previously untreated lesions and selected recurrent lesions. Between January 1988 and December 2000, we treated 322 patients by CO2 laser at a single institution; 37 had Tis, 191 T1a, 55 T1b, and 39 T2 lesions (mean follow-up, 77 months; range, 6 to 180 months). Kaplan-Meier curves showed a 5-year overall survival rate of 88%, a determinate survival rate of 99%, a disease-free survival rate of 81%, a rate of ultimate local control with laser alone of 91%, and a laryngeal preservation rate of 97%. Univariate and multivariate analysis showed that the only factor that statistically affected endoscopic control was lateral extension of the tumor with involvement of the bottom of the ventricle (hazard risk ratio, 4.0; 95% confidence interval, 1.71 to 9.35). The 58 recurrences were classified according to their location compared with the site of the primary tumor as follows: 14 in the same area (group A), 27 in adjacent subsites with superficial spreading or multifocal distribution (group B), and 17 in adjacent sites by submucosal diffusion to the visceral spaces, cartilaginous framework, or extralaryngeal tissues (group C). For each group, we analyzed the rate of patients who underwent salvage by endoscopic or open neck procedures and the rate of laryngeal preservation. Recurrences in groups A and B were endoscopically treated in 86% and 74% of cases, respectively. By contrast, in group C no patient was endoscopically cured, and there was a low laryngeal preservation rate (47%). The pathways of spread in recurrent carcinoma are therefore the single most important factor in predicting its endoscopic curability

Oral rehabilitation of oncology patients with dental implants after reconstruction surgery with autogenous flaps

OBJECTIVE: Reconstruction after radical cancer surgery in terms of function and esthetics can be quite demanding. The aim of this study was to evaluate oral rehabilitation with autogenous flaps and dental implants for maxillofacial reconstruction in oncologic patients after implant insertions. MATERIALS AND METHODS: The study consisted of 19 patients diagnosed with either squamous cell carcinoma, fusocellular carcinoma, or mucoepidermoid carcinoma. The reconstruction of the maxillofacial defects was done with autogenous flaps (free fibular flap, antero-lateral thigh flap, radial forearm flap, or rotational pedicled temporal muscle flap). Implants were inserted on the average 32.03±19.51 months after reconstructive operations. A total of 82 implants were inserted. Mean follow-up after maxillo-facial surgery was 7.2 years (mean 86.56±22.04 months). Mean follow-up after implant insertions was 4.5 years (mean 54.6±21.82). Primary outcome was implant survival. Secondary outcome was evaluation of post-surgical complications. RESULTS: There were surgical revisions in seven patients after reconstructive surgery with flaps, mainly due to tumor relapse. Complications were seen in 11 patients. There was one implant failure. Overall implant survival rate was 98.8%. No relations were found between implant survival rate and gender, type of tumor, type of microvascular free flap, radiation therapy, chemotherapy, and prosthesis type. CONCLUSIONS: According to the results of this study, oral rehabilitation with dental implants inserted in free flaps for maxillofacial reconstruction after ablative oncologic surgery can be considered as a safe treatment modality with successful outcomes

Search for H→γγ produced in association with top quarks and constraints on the Yukawa coupling between the top quark and the Higgs boson using data taken at 7 TeV and 8 TeV with the ATLAS detector

A search is performed for Higgs bosons produced in association with top quarks using the diphoton decay mode of the Higgs boson. Selection requirements are optimized separately for leptonic and fully hadronic final states from the top quark decays. The dataset used corresponds to an integrated luminosity of 4.5 fb−14.5 fb−1 of proton–proton collisions at a center-of-mass energy of 7 TeV and 20.3 fb−1 at 8 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. No significant excess over the background prediction is observed and upper limits are set on the tt¯H production cross section. The observed exclusion upper limit at 95% confidence level is 6.7 times the predicted Standard Model cross section value. In addition, limits are set on the strength of the Yukawa coupling between the top quark and the Higgs boson, taking into account the dependence of the tt¯H and tH cross sections as well as the H→γγ branching fraction on the Yukawa coupling. Lower and upper limits at 95% confidence level are set at −1.3 and +8.0 times the Yukawa coupling strength in the Standard Model

Fiducial and differential cross sections of Higgs boson production measured in the four-lepton decay channel in pp collisions at √s = 8 TeV with the ATLAS detector

Measurements of fiducial and differential cross sections of Higgs boson production in the H→ZZ∗ → 4ℓ decay channel are presented. The cross sections are determined within a fiducial phase space and corrected for detection efficiency and resolution effects. They are based on 20.3 fb−¹ of pp collision data, produced at √s = 8 TeV centre-of-mass energy at the LHC and recorded by the ATLAS detector. The differential measurements are performed in bins of transverse momentum and rapidity of the four-lepton system, the invariant mass of the subleading lepton pair and the decay angle of the leading lepton pair with respect to the beam line in the four-lepton rest frame, as well as the number of jets and the transverse momentum of the leading jet. The measured cross sections are compared to selected theoretical calculations of the Standard Model expectations. No significant deviation from any of the tested predictions is found

Search for the Standard Model Higgs boson decay to μ+μ− with the ATLAS detector

A search is reported for Higgs boson decay to μ+μ−μ+μ− using data with an integrated luminosity of 24.8 fb−124.8 fb−¹ collected with the ATLAS detector in pp collisions at √s=7 and 8 TeV at the CERN Large Hadron Collider. The observed dimuon invariant mass distribution is consistent with the Standard Model background-only hypothesis in the 120–150 GeV search range. For a Higgs boson with a mass of 125.5 GeV, the observed (expected) upper limit at the 95% confidence level is 7.0 (7.2) times the Standard Model expectation. This corresponds to an upper limit on the branching ratio BR(H→μ+μ−)of 1.5×10−31.5×10−3

Thyroid metastasis from rectal adenocarcinoma involving the airway treated by crico-tracheal resection and anastomosis: The role of palliative surgery

A 59-year-old woman underwent surgical removal of a pT3N3M0 rectal adenocarcinoma (RAC) through an abdominal-perineal approach followed by chemoradiotherapy (CHT-RT) in 1995. She underwent a right inferior lobectomy for a lung metastasis 3 years later, followed in 2000 by an additional intervention for a second metastasis that was treated by a left superior atypical lobectomy and CHT. The patient complained 1 year later of dysphagia and an anterior neck mass was found. US examination detected a multifocal lesion in the thyroid gland with involvement of the strap muscles, which was confirmed by FNAB to be a third RAC metastasis. A palliative course of RT was performed, but no regression of the lesion was observed. Crico-tracheal infiltration was also suspected after CT scan. The patient was in good general condition and strongly favored surgery. In August 2001 she underwent total thyroidectomy, total parathyroidectomy, strap muscles excision, central compartment neck dissection and crico-tracheal resection and anastomosis involving the anterior arch of the cricoid between the crico-thyroid joints and the first three tracheal rings. She was extubated at the end of the surgical procedure with no tracheotomy, started an oral diet the day after, and was discharged without complications 9 days later. She was followed up monthly by endoscopy and has undergone one CT and two MR scans at 6-month intervals. The patient had no RAC recurrence in the neck when last seen 26 months after surgery. During this time, she underwent four further lung metastasectomies followed by CHT