Kenya Fujita

Effects of hypoglossal and facial nerve injuries on milk-suckling.

Functional roles of the perioral anatomical structures involved in breastfeeding were examined in newborn rat pups in which the hypoglossal (XII) and facial (VII) nerves had been resected at the neonatal stage. The XII nerve controls tongue movement and is comprised of two functionally distinct branches: the medial branch related to protrusion of the tongue and the lateral branch related to its retraction. Newborn rat pups with bilateral resection of either of the XII nerve components (main trunk: XII‐trunk; medial branch: XII‐med; lateral branch: XII‐lat) failed to suckle milk and did not survive. Unilateral XII nerve‐resected neonates showed different milk‐suckling capabilities, which thus resulted in differences in survival rate (XII‐trunk: 38%; XII‐med: 24%; XII‐lat: 92%) and postnatal growth during the postnatal 3 weeks until P21. Unilateral and bilateral resections of the VII nerve innervating the buccolabial musculature produced lowered suckling capabilities and retarded postnatal growth, although all pups showed 100% survival. The results indicate a crucial role of the tongue, especially of protruding muscular elements innervated by the XII‐med nerve, in breastfeeding. The results also indicate differential effects of the VII and XII nerve components on suckling capability, survival, and postnatal growth of newborn rat pups.

Cell bodies of the trigeminal proprioceptive neurons that transmit reflex contraction of the levator muscle are located in the mesencephalic trigeminal nucleus in rats.

Abstract Since the levator and frontalis muscles lack interior muscle spindles despite being antigravity mixed muscles to involuntarily sustain eyelid opening and eyebrow lifting, this study has proposed a hypothetical mechanism to compensate for this anatomical defect. The voluntary contraction of fast-twitch fibres of the levator muscle stretches the mechanoreceptors in Müllers muscle to evoke proprioception, which continuously induces reflex contraction of slow-twitch fibres of the levator and frontalis muscles. This study confirmed the presence of cell bodies of the trigeminal proprioceptive neurons that transmit reflex contraction of the levator and frontalis muscles. After confirming that severing the trigeminal proprioceptive fibres that innervate the mechanoreceptors in Müllers muscle induced ipsilateral eyelid ptosis, Fluorogold was applied as a tracer to the proximal stump of the trigeminal proprioceptive nerve in rats. Fluorogold labelled the cell bodies of the trigeminal proprioceptive neurons, not in any regions of the rat brain including the trigeminal ganglion, but in the ipsilateral mesencephalic trigeminal nucleus neighbouring the locus ceruleus. Some Fluorogold particles accumulated in the area of the locus ceruleus. The trigeminal proprioceptive neurons could be considered centrally displaced ganglion cells to transmit afferent signal from the mechanoreceptors in Müllers muscle to the mesencephalon, where they may be able to make excitatory synaptic connections with both the oculomotor neurons and the frontalis muscle motoneurons for the involuntary coordination of the eyelid and eyebrow activities, and potentially to the locus ceruleus.

Effects of bilateral resection of facial nerves on suckling in developing rats

The purpose of the present study is to investigate functional role of the facial nerve on suckling in developing rats. The bilateral resection of facial nerves on postnatal day 1 (P1) resulted in cell loss of facial motoneurons and complete facial paralysis without any whisker movement or nictitating reflex at the end of the postnatal 3 weeks. Although the body weight of the nerve-resected rats increased gradually for the postnatal 3 weeks, they weighed less than the control rats without nerve resection. The nerve-resected rats contained less milk (0.25 +/- 0.02 g) than the control rats (0.35 +/- 0.02 g) in the stomach on P17. On P21, the body weight of the nerve-resected rats (25.33 +/- 0.32 g) was decreased by 28% compared to that of the control rats (35.08 +/- 0.57 g). Although their growth was substantially more retarded than that of the control animals, most (92%) of the nerve-resected pups could survive without facial nerve innervation. The orofacial musculature innervated by the facial nerve plays an important role in breastfeeding, but the present study shows that these muscles are not essential for the survival of neonatal rats.

Usefulness of Infrared Thermal Imaging Camera for Screening of Postoperative Surgical Site Infection after the Nuss Procedure

Introduction and Objective. The Nuss procedure is widely used in the treatment of pectus excavatum worldwide. Postoperative pectus bar infection is one of the most serious complications associated with this procedure. Therefore, early detection of signs of implant infection is very important. However, this is difficult, and effective methods have yet to be established. Methods. We use a handheld infrared thermal imaging camera to screen patients for postoperative infection following the Nuss procedure. Here, we report a 28-year-old man with recurrent postoperative (Ravitch procedure) pectus excavatum. Results. Infrared thermography camera clearly indicated slight cellulitis in the right chest. Conclusion. Our technique may assist in preventing postoperative bar infection and removal caused by severe bar infection. Furthermore, this camera is potentially suitable for many situations in infection monitoring following subcutaneous implant surgery.

The practical procedure of tumescent technique in burn surgery for excision of burn eschar.

The tumescent technique, which involves injection of large volumes of dilute epinephrine solution into subcutaneous fat, has been shown to markedly increase the safety of liposuction surgery, which is associated with risks of blood loss. The authors use this technique during burn surgery and developed a practical method of determining the amount of solution injected. The authors have applied the tumescent technique consisting of subeschar infiltration of dilute epinephrine (1 mg/L) in thermoneutral (37°C) saline. Preoperatively, a 5 × 5 cm square grid pattern is drawn on the burn wound, which facilitates estimation of the amount of infiltrated solution. The authors injected 20 ml of solution per square in the grid. Ten consecutive patients underwent 15 surgical procedures for tangential excision and split-thickness skin grafting. There were no complications during the intraoperative or postoperative period. Their method using a grid pattern drawn on the tissue being treated by the tumescent technique in burn surgery facilitates the excision of burn eschar.

Lateral vermilion border transposition flap to correct vermilion deformities with unilateral or bilateral cleft lip

Abstract Previously, bilateral lateral vermilion border transposition flaps were reported to correct whistling lip deformity in patients with cleft lip. This study examined the long-term outcome in these patients and modified the procedure. Here, the use of this procedure is reported in 69 cleft lip patients. The follow-up period after the operation ranged from 4–14 years. In addition to the standard method, a unilateral flap was applied for asymmetrical vermilion and small bilateral flaps were applied to loosen the transverse tightness of the vermilion. The asymmetry of the tightness was improved in all patients. The reconstructed tubercle diminished in volume gradually over a few years postoperatively. Secondary deformities after its use were subtly everted tubercle during smiling (18.8%) and irregularities on the labial-free margin (21.7%). They were corrected by minor follow-up revision. Although it is necessary to wait several years until the postoperative shape has stabilised, this is a simple and widely available method to reconstruct a naturally-shaped vermilion in cleft lip patients.