High-intensity focused ultrasound for localized thyroid-tissue ablation: preliminary experimental animal study.

OBJECTIVE: Thyroid surgery is common and complications are not rare. High-intensity focused ultrasound (HIFU) could be a possible minimally invasive alternative to surgery. The aim of this study was to assess the feasibility of using HIFU to obtain localized ablation of thyroid tissue without affecting neighboring structures. METHODS: The ewe was chosen as the model because its thyroid is easily accessible, with a size comparable to the human gland. An HIFU device designed to treat human prostate cancer was used. Eight ewes were anesthetised and their thyroids were ablated with ultrasound-guided HIFU. HIFU was generated by a 3-MHz spherical piezocomposite transducer that delivered an average of 24 (range, 9-44) ultrasound pulses per lobe covering a mean volume of 0.7 cm(3) (range, 0.2-1.8). RESULTS: Ewes were sacrificed 6-13 days after HIFU treatment and the anterior part of the neck was fixed in formalin before macroscopic and microscopic examinations. Adverse events occurred mainly for the first treated ewes before the energy delivered to the thyroid tissues was fully mastered: one animal died 3 days after HIFU, most probably because of inhalation pneumonia; the ultrasound beam hit adjacent organs in three animals. As expected, typical histologic lesions of the thyroid were obtained: central coagulative necrosis with ghost vesicular structures, disappearance of the nuclei, and cytoplasmic flocculation. At the periphery of the necrotic zone, a cell reaction was observed with fibroblastic granulation tissue, mononuclear cell infiltrate and regenerating thyroid tissue. CONCLUSION: The results of this preliminary study confirm the possibility of using HIFU in order to destroy a defined area in thyroid tissue. Future experiments in ewes will be focused on the safety of the method by refining the HIFU parameters and by developing a new equipment specially built for the thyroid.

Rehabilitation of congenital facial palsy with temporalis flap--case series and literature review.

BACKGROUND: Congenital facial paralysis is a rare disorder with an incidence of less than 1 in 1000 live births. Several surgical rehabilitation techniques have been described, such as free flaps or transpositions of the temporalis muscle. We report our experience of transposition of the temporalis muscle in this indication. MATERIALS AND METHODS: Retrospective monocentric study between January 2005 and December 2009. RESULTS: Five children (mean age at the surgery: 7.3 years, range 6-13) presenting with a congenital facial paralysis were treated by a temporalis muscle transposition during the considered period. An etiological assessment was achieved by carrying out a petrous bone CT, a cerebral and petrous MRI, and audiometric evaluation. Four patients out of 5 (80%) showed a satisfactory and stable functional outcome over time (average follow-up: 26 months). CONCLUSION: Temporalis muscle transposition is a single-stage procedure, easily adapted for the pediatric condition of congenital facial paralysis. It is our opinion that this procedure needs to be carried out at the end of the pre-school period.

Autologous fat transfer in velopharyngeal insufficiency: indications and results of a 25 procedures series.

OBJECTIVE: To assess the efficiency of autologous fat transfer (AFT/Coleman procedure) in the management of velopharyngeal insufficiency (VPI). SETTINGS: Tertiary academic center, retrospective case series over a 4 year period. Pre- and post-speech assessment by a speech pathologist using the Borel-Maisonny scale. PATIENTS AND METHOD: Twenty-five (25) procedures were performed on 22 patients during the considered period. Mean age at surgery was 12.4 ± 4.1 years-old. Main associated conditions were 22q11 deletion (n=6 including 2 with cleft palate), isolated cleft palate (n=3), and Robin sequence (n=2). Indications were VPI grade 2a (n=5), 2b (n=11) and 3 (n=6), despite prolonged speech therapy (pre-op mean duration: 4.2 years) and previous surgery (velopharyngoplasty, n=13). Four patients had a contraindication of velopharyngoplasty (aberrant internal carotid arteries). RESULTS AND CONCLUSION: Fat harvesting sites were umbilicus (n=23) and buttock (n=2). Mean injected fat volume was 7.8 ml, in the posterior wall of the pharynx (n=25) the soft palate (n=15), the peritonsillar arches (n=3), and the pre-existing flap (n=3). Mean follow-up was 17 months. Two patients relapsed once and one patient twice, requiring additional injections. Final post-operative examination 1 year after the last procedure showed an improvement of speech in 90% of cases (grade 1, n=2; 1/2a, n=5; 2a n=10; 2b, n=5). AFT is a safe technique indicated in the primary and secondary management of VPI, with stable results on speech. However, if a complete return to normal is difficult to achieve, its simplicity allows multiple procedures in the same patient.