Masaaki Kosaka

Enhancement of rat peripheral nerve regeneration through artery-including silicone tubing

Regeneration of rat sciatic nerve across a 5-mm excised gap was investigated after the proximal and distal stump were inserted into a silicone tubing including a native artery. Usual tubulation (silicone tube only) was used as the control. After 4, 8, and 15 weeks, the extent of nerve regeneration was evaluated electrophysiologically and histologically. The nerve regeneration and intraneural vascular reconstruction that occurred within silicone tubing with an arterial blood supply were more successful than those that occurred in the control. In the 4 weeks following implantation, the enhancement of maturation in the regenerating axons was especially noticeable. The advantages of the present procedure are (i) the provision of continuous guidance for neural outgrowth; (ii) an increased supply of nutrients for regenerating nerve fibers and Schwann cells; (iii) an increased supply of oxygen by arterial highly oxygenated blood; and (iv) the stimulation of an exchange effect within the tube due to the pumping action of artery.

Intracranial migration of fixation wires following correction of craniosynostosis in an infant

BACKGROUND In the craniofacial skeleton, osseous fixation techniques for stabilization include stainless steel wire, miniplates or bioresorbable plates; in some cases, stainless steel wires are still indicated. Most recently, several case reports have demonstrated that microplates or stainless steel wires migrate intracranially when used in the craniofacial skeleton in neonates. PATIENT We present the case of a 7-year-old male who underwent treatment of brachycephaly at the age of 5 months. In this patient, internal migration of wires was observed. CONCLUSION In our opinion, there is a difference between migration of wires and of plates in the growing cranium. Factors affecting the incidence of material migration in cranioplasty are believed to include (1) age, (2) site and (3) the material itself.

Morphologic Study of Normal, Ingrown, and Pincer Nails

BACKGROUND Pincer nail has been confused with ingrown nail for decades. OBJECTIVE The objectives were to analyze the circumferential length of pincer nail and the relationship between nail deformity and the underlying distal phalangeal shape. METHODS The circumferential length of 53 pincer nails was determined at successive 5‐mm intervals of the nail plate. Sixty great toes, including normal (n=20), ingrown (n=20), and pincer nails (n=20), were assessed with respect to body height, body weight, body mass index, nail height, nail width index, and nail height index. Nail angle and height of osteophyte were measured. RESULTS Despite the presence or absence of overcurvature, the circumferential length displayed nearly identical values across the proximal to distal range of the nail. In the pincer nail group, only the correlation between the width and height indices was statistically significant; 50%, 80%, and 100% of cases were confirmed based on osteophyte presence in normal, ingrown, and pincer nails. CONCLUSION The findings suggest that the mechanical cause may be associated with the over curved nail, which is affected by nail bed contraction. Results may support the hypothesis that an osteophyte of the distal phalanx may not be a cause of, but rather a result of, an overcurving deformity. The authors have indicated no significant interest with commercial supporters.

Pincer nails treated using zigzag nail bed flap method: results of 71 toenails.

BACKGROUND In instances of pincer nail deformity, patients complain of pain associated with walking, wearing shoes, or light touching. Cosmetic concerns and difficulties in terms of nail clipping also arise. Achievement of a satisfactory nail form remains elusive. OBJECTIVE To introduce our original surgical procedure and present the satisfactory results. MATERIALS & METHODS The zigzag nail bed flap method was used on 71 toenails in 49 patients displaying pincer nails (11 male, 38 female; age range 12–88, mean, 48.6). This investigation evaluated 70 nails from the great toe and one nail from a second toe. RESULTS No postoperative complications, including pain, infection and conspicuous scars, were evident. The degree of improvement was determined objectively with the width and height indices, revealing the accuracy of this therapeutic measure. CONCLUSION The authors recommend surgical intervention consequent to the vicious cycle corresponding to anatomical abnormalities associated with the nail plate–nail bed–phalanges relationship. Therefore, these architectures should be treated in conjunction rather than singularly.

Energy metabolism in unrestrained fish with in vivo 31P-NMR

Abstract 1. 1. We evaluated changes in high energy phosphate metabolism in unrestrained freshwater loaches by in vivo 31 P-NMR. 2. 2. When dissolved oxygen was deficient, both an increase in Pi and a decrease in PCr were observed as the loach struggled. 3. 3. After pretreating the fish with an anesthetic agent, we observed the dependence of high energy phosphate metabolism on changes in dissolved oxygen. 4. 4. Under anesthetic [Pi]/[Pi] + [PCr] ratio, an index of metabolic state, was lower than without anesthesia. 5. 5. Decrease in high energy phosphate metabolism in fish during oxygen deficiency was not caused by poor oxygen supply but resulted from struggle movement due to lack of oxygen.

Nasal bone clip: a novel approach to nasal bone fixation.

Background:Nasal bone fracture is a common injury, but its repair can be unexpectedly difficult. To date, intranasal gauze packing has been used to support the nasal bone in position and to maintain contact between the mucosa of the septum and the cartilage. This gauze packing, however, has a tendency to shift, resulting in an inflammatory response characterized by a foul odor until removal, which detracts from the comfort of the patient. We developed a novel device, the nasal bone clip (NBC), which provides a satisfactory nasal airway and improved comfort. Methods:A 1.2-mm Kirschner wire and a small piece of hydrocolloid wound dressing are used. The single wire is bent into a double-curved shape, after which each of the 2 tips is curled with pliers. The end of the wire in the nasal passage is covered with a piece of wound dressing to protect the mucosa. After reduction, the external portion of the wire is inserted on the surface of the splint. Results:The NBC was applied in 14 cases: 12 instances of fresh fractures and 2 of old fractures; there were 8 men and 6 women; their mean age was 19.9 years. Complications were not observed; moreover, no patients exhibited problems during the treatment. Conclusions:The advantages of the NBC are that all materials are available in the operating room or outpatient department, it is low cost, it is readily installable and detachable, it affords superior support for gauze packing, it provides effective external splinting with intranasal support, it never disturbs the nasal airway, and it offers comfort.

Retrograde dacryocystography (RDC) utilizing a round-tipped needle

Because the application of conventional anterograde dacryocystography has been restricted in cases with an intact lacrimal punctum, the indications are rather limited. The authors developed a new method for retrograde dacryocystography (RDC) using a hand-made round-tipped needle inserted directly into the orifice of the nasolacrimal duct. A 60 mm long aluminum tube (3 mm in diameter) was used to prepare the round-tipped needle. The distal portion of the tube was bent to an angle of about 80 degrees. The tip was then coated with synthetic resin adhesive to make it round. Following the insertion of the round-tipped needle directly into the inferior meatus, the tip was moved back and forth to find the orifice without visual observation. The complete insertion of the tip of the needle into the nasolacrimal duct was recognized by a fixed sensation of the tip. Contrast medium was then injected, and PA radiography was carried out. In the present paper, the authors report the usefulness of RDC, which is applicable even in cases of injury or obstruction in the upper lacrimal system. In 16 of 20 patients, the quality of the RDC images was judged as excellent. RDC can be carried out within a few seconds after acquiring the technical skills, and is thought to be a useful method, especially in cases of upper lacrimal injury.

Different onset pattern of oculocardiac reflex in pediatric medial wall blowout fractures.

PurposeWe report the 2 pediatric patients who had radiographic confirmation of a rare case of medial orbital wall “trapdoor” fracture with extraordinary symptoms of oculocardiac reflex (OCR). MethodsThis was a small interventional case series. ResultsThis is the retrospective report of 2 boys (13 and 10 years old) who developed diplopia, pain, nausea/vomiting, and general malaise following blunt trauma. However, the onset pattern of OCR was absolutely different: delayed onset of OCR just following therapeutic forced duction test to treat the orbital content herniation in the first case and a sudden onset after injury in the second case. In both cases, urgent surgery led to complete normalization of ocular motility. ConclusionsPrompt diagnosis and proper treatment are critical to maximize clinical outcome for this rare and critical trauma.

Bilateral parotid sialoadenitis with gonial hypertrophy

Sialoadenitis is a non‐inflammatory condition that affects mainly the parotid, and is characterised by bilateral, painless swelling, which is an appreciable problem in young women. A 28‐year‐old woman presented with parotid sialoadenitis with masseteric hypertrophy. She was treated by superficial parotidectomy and ostectomy of the mandibular angle and made an uncomplicated recovery.

A Rare Case of Rapid Progression from Incurved Nail to Pincer Nail

Pincer nail, which is characterized by transverse overcurvature of the nail plate and progressive pinching distally, is a rare dystrophy of unknown pathogenesis. Several causative factors have been identified, including heredity, psoriasis, ill-fitting shoes, subungual exostoses, drug induction, trauma, and other idiopathic agents. This condition existed in many patients for extended periods before medical intervention, but the early pathology of this deformity remains unclear. We describe a rare case involving a mild incurved nail that progressed rapidly to severe pincer nail.