Posterior auricular artery helix root free flap-part I: radio-anatomical study.

Full-thickness defects of the distal nose are an ongoing surgical challenge. Among the available techniques, pre-auricular chondrocutaneous free flaps based on the superficial temporal artery (STA) have good aesthetic and functional outcomes. However they often require autologous venous grafts. The aim of this radio-anatomical study was to evaluate the feasibility of the helix root free flap based on the posterior auricular artery (PAA). Vascular lengths, diameters, and networks were investigated in flaps harvested from cadavers. The perfusion of the flaps was studied by injecting patent blue. Some flaps were also injected with contrast agent and studied by angiography and computed tomography. Ten flaps from seven fresh cadavers were dissected and analysed. The mean length of the PAA was 114.2 mm and the mean diameter was 2.2 mm. Perfusion was investigated in six flaps and considered good in three of these. The study results demonstrate the feasibility of PAA-based helix root free flaps. This alternative technique provides an 11 cm pedicle with vessels of appropriate calibre, facilitating any potential microsurgery. The scar is mostly hidden behind the ear. This PAA-based helix root free flap could be a reliable and promising single-stage procedure to repair complex defects of the alae nasi.

Posterior auricular artery helix root free flap-part II: clinical application.

The surgical repair of full-thickness defects involving the alae nasi is complex. Pedicle flaps such as frontal and nasolabial flaps can be used, but require several interventions with different techniques. In contrast, free flaps from the foot of the ear helix allow the three layers of the nasal wings to be reconstructed in a single operation. Nevertheless, in the classical approach, the vascular pedicle is short. Although some authors have proposed raising the flap in a retrograde manner, this still yields a relatively short pedicle with narrow vessels. In the companion paper, we demonstrated that a posterior auricular artery helix root free flap (PAAHF) can be harvested from the posterior auricular vessels, thus increasing the useful pedicle length. The case of a patient with basal cell carcinoma of the left ala is presented here. A right helix root free flap was anastomosed with the facial vessels at the left mandibular notch. This new flap overcomes the main limitation of the classical helix root flap, namely the length of the pedicle. It has all of the morphological qualities of the classical flap, but with simpler vascular assembly, since autologous venous grafts and complex anastomoses are not required.

Identifying a neuroanatomical signature of schizophrenia, reproducible across sites and stages, using machine learning with structured sparsity.

OBJECTIVE: Structural MRI (sMRI) increasingly offers insight into abnormalities inherent to schizophrenia. Previous machine learning applications suggest that individual classification is feasible and reliable and, however, is focused on the predictive performance of the clinical status in cross-sectional designs, which has limited biological perspectives. Moreover, most studies depend on relatively small cohorts or single recruiting site. Finally, no study controlled for disease stage or medication's effect. These elements cast doubt on previous findings' reproducibility. METHOD: We propose a machine learning algorithm that provides an interpretable brain signature. Using large datasets collected from 4 sites (276 schizophrenia patients, 330 controls), we assessed cross-site prediction reproducibility and associated predictive signature. For the first time, we evaluated the predictive signature regarding medication and illness duration using an independent dataset of first-episode patients. RESULTS: Machine learning classifiers based on neuroanatomical features yield significant intersite prediction accuracies (72%) together with an excellent predictive signature stability. This signature provides a neural score significantly correlated with symptom severity and the extent of cognitive impairments. Moreover, this signature demonstrates its efficiency on first-episode psychosis patients (73% accuracy). CONCLUSION: These results highlight the existence of a common neuroanatomical signature for schizophrenia, shared by a majority of patients even from an early stage of the disorder.

Unusual cystic lesion of the eyebrow: A case report of malignant chondroid syringoma.

INTRODUCTION: Malignant chondroid syringomas, also known as cutaneous malignant mixed tumors, are rare neoplasms that most frequently occur on the torso or extremities of women. Here, we present an illustrated case of a facial malignant chondroid syringoma. MATERIALS AND METHODS: A 32-year-old female patient with no notable medical history presented with an approximately 1cm-wide, painless, palpably-mobile subcutaneous nodule, suggestive of a sebaceous cyst, just above the middle third of the right eyebrow. The nodule had grown steadily over six months. She had no palpable cervical lymphadenopathies. RESULTS: Anatomic pathology of the enucleated nodule found an adnexal sudoriparous tumor measuring 6×10mm and indicative of a malignant chondroid syringoma. Cervicofacial computed tomography and positron emission tomography scans showed no near or distant lymph node involvement. A second intervention for wide excision around the original enucleation lesion (+1cm) was validated in a multidisciplinary, cancerology-dermatology consultation. The eyebrow was reconstructed with a temporally-harvested fasciocutaneous island flap. DISCUSSION: Malignant chondroid syringomas are very rare and thus no standardized treatment has been established for them. Only 12 craniofacial localizations have been described to date. Radiation therapy and chemotherapy have not been shown effective for this malignancy, leaving only wide excision as a therapeutic option. A high and sustained (as much as 20 years after the initial diagnosis) risk of recurrence or metastasis necessitates prolonged patient follow-up.

Anatomic and histological study of the rabbit mandible as an experimental model for wound healing and surgical therapies.

The rabbit is one of the most widely used models for studying bone remodeling or dental implant osseointegration but very few data are available about the rabbit's mandible. The aim of this work was to describe the anatomy of the rabbit mandible and to estimate the available bone volume for experimental studies. First, with a dissection, the morphology of the mandible was described and the mental foramen, the position of the main salivary glands and muscular insertions were located. Then, by X-ray imaging, the position of the inferior alveolar canal, the dental root courses and volume and bone density were described. Finally, with frontal sections of the mandible body, the rabbit's dental and alveolar bone histological structure were assessed. Thus, the relevance of the rabbit mandible as an experimental model for wound healing or surgical therapies was discussed.

[Pre-implantation bone graft coffering technique for posterior mandibular edentulism: between onlay grafting and regeneration]. / Technique du coffrage en greffe osseuse préimplantaire mandibulaire postérieure : entre apposition et régénération.

BACKGROUND: Pre-implant placement posterior mandibular bone grafts remain a challenge for maxillofacial surgeons. We present a coffering technique we prefer using in this localization. SURGICAL PROCEDURE: This original technique involves creating a sagittal mandibular groove in which a graft harvested from the retromolar region is wedged vertically, after being sharpened in a bone mill. Reconstruction of the alveolar region itself is achieved by filling up the space between this vestibular coffer and the residual alveolar ridge with particulate bone graft from the bone mill. RESULTS: A hundred patients were operated with this technique by the same team from 2005 to 2010. The treatment failed for four patients at 3 post-operative months. No alteration of inferior alveolar nerve was observed. DISCUSSION: This coffering technique seems to be fully adequate in case of a posterior mandibular atrophy with a narrow ridge and sufficient bone height. This technique has several assets. Guided bone regeneration is associated with the use of exclusively autologous bone grafts. It may be performed under local anesthesia. The donor site is close, and the regenerated bone is of good quality. Implant placement must be achieved from 4 to 6 months after graft surgery. The drawbacks of the technique are related to donor site possibilities, and to the alveolar ridge height. Morbidity is low.

[Eagle syndrome: a rare and atypical pain!]. / Le syndrome d'Eagle: une douleur mal connue et mal reconnue!

The styloid process projects down and forward from the inferior surface of the petrous bone. It arises from the second branchial arch. Its average length ranges from 22 to 33 mm. The styloid process hypertrophy, or Eagle syndrome, may be a source of cervicofacial pain and is very difficult to diagnose. The pathogenesis of this abnormality is unknown. Traumatic origin is usually admitted even if recent embryological data suggest a genetic origin with interindividual variations. The diagnosis is made on several elements: exacerbated cervical pain on neck hyperextension and sudden head movements, typical pain caused by palpation of the tonsillar fossa, diagnostic test with xylocain, and radiological investigation. Treatment is surgery and exeresis of the styloid process via a transoral or cervical approach.