Scar-centered dilation in the treatment of large keloids.

BACKGROUND: Hypertrophic scars and keloid treatment is a major problem in plastic surgery. While small keloids can be treated with resection followed by radiotherapy, large keloids require treatment with a tissue expander. Conventional methods increase the need for auxiliary incisions, causing new scar hyperplasia. AIM: To introduce a new method for the treatment of keloids with an expander. METHODS: Between 2018 and 2021, we performed surgeries to treat large keloids in nine patients with a two-stage approach. In the first stage, an intrascar incision was made in the keloid, and a customized expander was implanted under the keloid and the surrounding normal skin. A period of 3-6 mo was allowed for skin expansion. In the second stage, after the initial incision healed, a follow-up surgery was performed to remove the expander, resect the keloid, and repair the expanded skin flap. To accomplish this, an incision was made along the scar boundary to avoid making a new surgical incision and creating new scars. Superficial radiotherapy was then performed postoperatively. RESULTS: Two patients had anterior chest keloids. After treatment, the anterior chest incision was broken repeatedly and then sutured again after debridement. It healed smoothly without scar hyperplasia. Keloids were successfully removed in 7 patients without recurrence. CONCLUSION: This method was performed through a keloid incision and with a custom expander embedded. After full expansion, the keloid was directly resected using a linear suture, which avoids new surgical incisions and scars and can successfully remove large-area keloids. The treatment is effective, providing new insights and strategies for the treatment of similar large-area keloid and hypertrophic scar cases in the future.

Magnetoencephalography for epileptic focus localization based on Tucker decomposition with ripple window.

AIMS: To improve the Magnetoencephalography (MEG) spatial localization precision of focal epileptic. METHODS: 306-channel simulated or real clinical MEG is estimated as a lower-dimensional tensor by Tucker decomposition based on Higher-order orthogonal iteration (HOOI) before the inverse problem using linearly constraint minimum variance (LCMV). For simulated MEG data, the proposed method is compared with dynamic imaging of coherent sources (DICS), multiple signal classification (MUSIC), and LCMV. For clinical real MEG of 31 epileptic patients, the ripples (80-250 Hz) were detected to compare the source location precision with spikes using the proposed method or the dipole-fitting method. RESULTS: The experimental results showed that the positional accuracy of the proposed method was higher than that of LCMV, DICS, and MUSIC for simulation data. For clinical real MEG data, the positional accuracy of the proposed method was higher than that of dipole-fitting regardless of whether the time window was ripple window or spike window. Also, the positional accuracy of the ripple window was higher than that of the spike window regardless of whether the source location method was the proposed method or the dipole-fitting method. For both shallow and deep sources, the proposed method provided effective performance. CONCLUSION: Tucker estimation of MEG for source imaging by ripple window is a promising approach toward the presurgical evaluation of epileptics.