[Condylar hyperplasia: qualitative and quantitative study of temporomandibular joints remodeling before and after condylectomy]. / L'hypercondylie : étude qualitative et quantitative du remodelage des articulations temporo-mandibulaires avant et après condylectomie.

PURPOSE: This retrospective study aimed to evaluate bone remodeling of temporo-mandibular joints (TMJ) using computed tomography (CT) before and after condylectomy for condylar hyperplasia. MATERIAL AND METHOD: TMJ bone remodeling was studied by comparing the pre and postoperative CT scan of ten patients. Qualitative evaluation was performed by two-dimensional analysis. Three-dimensional analysis superimpositions were done after digital condylar units isolation. Condylar volume modifications were measured and compared on both sides. Lastly, before and after surgery, we studied the radio-clinic correlations. RESULTS: After surgery, all the operated condyles developed a new cortical bone. We noticed also a thickening of the glenoid fossa. Surgical condylectomy leaded to a 43.5% volume reduction on the operated side and 2.14% on the controlateral side. On the controlateral side, most of abnormalities seen preoperatively disappeared after surgery. For two patients, the condylar resection took away over 80% of the initial volume. For these patients, we observed major radiologic modifications on the controlateral TMJ associated with symptoms of dysfunction. These problems did not worsen their quality of life. CONCLUSION: Both TMJ presented with bone remodelling after condylectomy. In condylar hyperplasia, condylectomy provides orthopaedic results on dysmorphia and removal of the pathological prechondroblastic zone. In the future, an earlier detection of this pathology may help the surgeon to treat in childhood. This would limit surgical excision and would avoid important dysmorphia.

Vestibular orientation for craniofacial surgery: application to the management of unicoronal synostosis.

BACKGROUND: Standardized cephalometric measurements are necessary to compare skulls of different ages and sizes, in normal and diseased subjects, and in different species. In diseases involving the skull base, classical cephalometry is often impossible because the cranial landmarks are modified. In vestibular orientation (VO), the plane of the lateral semicircular canal (LSCC) of the inner ear, which has a constant relation to gravity, defines the horizontal plane of reference. Defining a reference plane independent of external landmarks is especially important in unicoronal craniosynostosis (UCCS), because the skull base is asymmetrical. AIM OF THE STUDY: To illustrate the interest of VO in clinical practice, we report on our experience with VO-based correction of UCCS. MATERIALS AND METHODS: Since 1992, we have used VO-3D computed tomography scanner for surgical planning of all patients with UCCS, measuring the required correction as the discrepancy between the theoretical and the observed midline. RESULTS: Thirty-eight children were operated under the age of 2 years for UCCS and evaluated after a mean follow-up of 66 months. Thirty-two (84%) were considered perfect, four (11%) had mild imperfection not requiring reoperation, and two (5%) required reoperation because of progressive craniosynostosis involving the sagittal suture. Good surgical results were obtained when the orbits were correctly oriented relative to the plane of the LSCC. CONCLUSIONS: VO is a useful reference system for the evaluation and surgical planning of UCCS. We hypothesize that the mismatch between the visual and labyrinthic sensorial inputs plays a role in the pathophysiology of UCCS.

Fluid-attenuated inversion recovery (FLAIR) sequences for the assessment of acute stroke: inter observer and inter technique reproducibility.

BACKGROUND AND PURPOSE: Diffusion-weighted magnetic resonance (MR) imaging (DWI), and three-dimensional (3D) time-of-flight (TOF) MR angiography (MRA), are highly sensitive for the early detection of stroke and arterial occlusion. However, only a few studies have evaluated the sensitivity of conventional MR sequences that are usually included in the imaging protocol. The aim of this study was to evaluate interobserver and intertechnique reproducibility of Fluid-Attenuated Inversion Recovery (FLAIR) sequences for the diagnosis of early brain ischemia and arterial occlusion. METHODS: Over a 30-month period, brain MR examinations were performed in 34 patients within 12 hours after stroke onset. Imaging protocol included FLAIR sequences, DWI and 3D TOF MRA. Ten observers including radiologists and neurologists, performed separately a visual interpretation of FLAIR images for the detection of brain ischemia and arterial occlusion seen as an arterial high signal. DWI and 3D TOF MRA were used as reference and interpreted independently by two senior radiologists. Interobserver agreement was assessed for image quality, detectability and conspicuity of lesions whereas intertechnique agreement was only judged for lesion detectability. RESULTS: On FLAIR sequences, interobserver agreement for the detection of brain ischemia and arterial occlusion was excellent (kappa = 0.81 and 0.87 respectively). The concordance between FLAIR and DWI sequences for the detection of brain ischemia and between FLAIR and 3D TOF MRA for the detection of arterial occlusion were judged as excellent for all observers (kappa = 0.91 and 0.89 respectively). CONCLUSION: Although DWI is the most sensitive technique with which to detect acute stroke, FLAIR imaging may also be useful to demonstrate both acute ischemia and arterial occlusion with an excellent interobserver reproducibility.