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Abstract Background Various techniques are applied in laparoscopic surgery for the treatment of urachal remnants, which are less invasive and associated with lower morbidity. We herein report a case series in which we treated urachal remnants and medial umbilical ligaments using a laparoscopic approach. Case presentation From 2015 to 2019, seven patients (male, n = 5; female, n = 2) with a urachal remnant were treated by laparoscopic surgery in our institute. Five boys and two girls with a median age of 11 years (range 10–15 years) were enrolled in this series. The clinical results of laparoscopic treatment, the perioperative records, and the pathologic results were evaluated. The operation was performed with the use of three ports and an EZ access® (Hakko Medical, Nagano, Japan), which is a silicon cap for the wound retractor (Lap Protector®, Hakko Medical, Nagano, Japan). The removal of the urachal remnant and medial umbilical ligaments was completed with a median operative time of 92 min (range 69–128). The median hospital stay after surgery was 4 days (range 2–5). No patients developed intra-postoperative complications or recurrence. Conclusions Although our data are preliminary, complete laparoscopic removal of symptomatic urachal remnants and medial umbilical ligaments was a safe and effective minimally invasive approach, with better cosmetic outcomes.

Inflammatory myofibroblastic tumor (IMT) is a rare but benign entity masquerading as a malignant tumor. We herein report an 18-month-old boy with small bowel wall IMT who presented with intussusception. He was transferred to our hospital with a complaint of abdominal pain and diagnosed with intussusception. On laparotomy, the small bowel wall mass consisted of solid tissue measuring 2.5 × 3.0 cm. The postoperative pathology examination revealed numerous spindle cells arranged in dense bundles with diffuse infiltration of inflammatory cells and tumor involvement of the mucosa and serosa. As the postoperative pathology examination resulted in a diagnosis of IMT and suspected partial resection, small bowel resection and mesenteric lymph node resection were performed two months after the first operation. A pathology examination after the second surgery revealed no evidence of residual IMT and negative findings for metastasis in the regional lymph nodes. IMT is a locally aggressive lesion. The immunophenotypic feature of ALK-1 in particular is associated with a high recurrence rate. Long-term follow-up is absolutely needed. Keywords: Inflammatory myofibroblastic tumour, Small intestine, Child, Intussusception, Anaplastic lymphoma kinase

We report on reversible electric-field-driven magnetic domain wall motion in a Cu/Ni multilayer on a ferroelectric BaTiO3 substrate. In our heterostructure, strain-coupling to ferroelastic domains with in-plane and perpendicular polarization in the BaTiO3 substrate causes the formation of domains with perpendicular and in-plane magnetic anisotropy, respectively, in the Cu/Ni multilayer. Walls that separate magnetic domains are elastically pinned onto ferroelectric domain walls. Using magneto-optical Kerr effect microscopy, we demonstrate that out-of-plane electric field pulses across the BaTiO3 substrate move the magnetic and ferroelectric domain walls in unison. Our experiments indicate an exponential increase of domain wall velocity with electric field strength and opposite domain wall motion for positive and negative field pulses. The application of a magnetic field does not affect the velocity of magnetic domain walls, but independently tailors their internal spin structure, causing a change in domain wall dynamics at high velocities.

Control of magnetic domain-wall motion by electric fields has recently attracted scientific attention because of its potential for magnetic logic and memory devices. Here, we report on a new driving mechanism that allows for magnetic domain-wall motion in an applied electric field without the concurrent use of a magnetic field or spin-polarized electric current. The mechanism is based on elastic coupling between magnetic and ferroelectric domain walls in multiferroic heterostructures. Pure electric-field-driven magnetic domain-wall motion is demonstrated for epitaxial Fe films on BaTiO_{3} with in-plane and out-of-plane polarized domains. In this system, magnetic domain-wall motion is fully reversible and the velocity of the walls varies exponentially as a function of out-of-plane electric-field strength.