Dermal Nipple-Areola Complex Perfusion through Circumareolar Scars: A Delay Model in Two-Stage Nipple-Sparing Mastectomy.

BACKGROUND: Nipple-sparing mastectomy (NSM) has evolved as a standard surgical option. The NSM complication rate remains high in large breasts. To reduce the risk of necrosis, several authors have proposed delayed procedures to enhance blood supply to the nipple-areola complex (NAC). The purpose of this study in a porcine model was to show adequate redirection of NAC perfusion by neoangiogenesis through circumareolar scars. METHODS: Delayed two-staged NSM was simulated in 52 nipples (six pigs) with a 60-day interval. The nipples underwent a full-thickness, circumareolar incision onto the muscular fascia, with preservation of underlying glandular perforators. After 60 days, NSM was performed through a radial incision. A silicone sheet was introduced in the mastectomy plane to prevent NAC revascularization by wound bed imbibition. Digital color imaging was used to assess necrosis. Near-infrared fluorescence with indocyanine green was used to assess perfusion patterns and perfusion in real time. RESULTS: No NAC necrosis was seen after 60 days' delay in any nipples. In all nipples, indocyanine green angiography showed complete alteration of the NAC vascular perfusion pattern from subjacent gland to a capillary fill following devascularization, exhibiting a predominant arteriolar capillary blush without distinct larger vessels. CONCLUSIONS: NAC delay reverses glandular perfusion to adequate dermal neovascularization. Neovascularization through full-thickness scars provides sufficient dermal perfusion after 60 days' delay. Identical staged delay in humans may be a surgically safe NSM option and could broaden therapeutic NSM indications in difficult breasts. Large clinical trials are necessary to provide identical results in human breasts. CLINICAL RELEVANCE STATEMENT: NAC delay reverses glandular perfusion to adequate dermal neovascularization. Neovascularization through full-thickness scars provides sufficient dermal perfusion after 60 days of delay. Identical staged delay in humans may be a surgically safe NSM option.

Challenges in the anesthetic management of ambulatory patients in the MRI suites.

PURPOSE OF REVIEW: MRI is becoming an indispensable diagnostic tool. The need for prolonged motion-free periods has substantially increased the need for deep sedation or anesthesia in a challenging environment. This review summarises recent literature with respect to pharmacological sedative strategies, nonpharmacological alternative approaches, airway management and safety issues in the ambulatory setting. RECENT FINDINGS: Most literature researches the pediatric patient population. The American Society of Pediatrics published guidelines for monitoring and management of pediatric patients during sedation for diagnostic procedures. Dexmedetomidine is the most researched agent for sedation. It remains uncertain what the clinical implications are of the potential neurotoxicity of repeat sedation or anesthesia in young children. Airway strategies highlight the use of end-tidal carbon dioxide monitoring. Technical imaging advancement and nonpharmacological sedation alternatives allow for shorter procedures with a lower need for sedation. SUMMARY: The anesthetic management of ambulatory patients in the MRI environment has its specific challenges and safety issues. However, the implementation of safety guidelines, new pharmacological and alternative nonpharmacological sedation strategies offer interesting perspectives to tackle these challenges.