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Biomedical subjects

K Yokoi

Publications and source records attributed to K Yokoi.

At least 55 records · Page 3Linked to original sources
PubMed1999

Functional reconstruction using a depressor anguli oris musculocutaneous flap for large lower lip defects, especially for elderly patients.

Described here is a new technique to reconstruct large lower lip defects using one or two musculocutaneous island flaps, which includes an innervated depressor anguli oris muscle and has a facial artery in its pedicle. Vermilion is simultaneously reconstructed using a mucosal transposition flap. Three patients who had a total lower lip defect and five patients who had a defect larger than one-half of the lower lip were treated by our procedure. All the flaps survived completely without any signs of vascular stasis. In six patients, sphincter function and sensation appeared within 3 months after surgery. In one patient who needed a total lower lip reconstruction, the depressor anguli oris muscle was atrophic and the motor nerve could not be found. This patient could not regain motion. One other patient complained of a sialorrhea accompanied by sensory loss; however, his sensation improved within 6 months after surgery. All of the reconstructed lower lips were large enough to enable the patient to wear dentures and were of a cosmetically acceptable appearance 1 year after surgery.

Aged↗
PubMed1999

Paget's disease arising near a male areola without an underlying carcinoma.

We report a 56-year-old man with Paget's disease occurring near the left areola without any underlying breast carcinoma. Histologically, there was no evidence suggesting continuity with a lactiferous duct, accessory breast, or microscopic gynecomastia. We review previous case reports of Paget's disease occurring in unusual sites and discuss their nomenclature from the histogenetic point of view.

Biopsy, Needle↗
PubMed1999

Lung cancer in patients under 50 years old.

A long-term retrospective study was carried out on 790 cases of lung cancer to determine if the clinicopathologic characteristics and survival rates of lung cancer patients under the age of 50 differ from those of patients 50 years of age or older at diagnosis by analyzing data on patients registered at Tochigi Cancer Center Hospital. Of the 790 patients, 77 (9.7%) were under the age of 50 at diagnosis. The percentage of women in the younger patient group was significantly higher than that in the older patient group (39.0% vs. 27.5%; P = 0.034). Tumor histology revealed a significant preponderance of adenocarcinomas (60 patients, 77.9%) and a paucity of squamous cell carcinomas (8 patients, 10.4%) in the younger age group (P<0.001). The preponderance of adenocarcinoma was significant in both males and females (male: P = 0.004, female: P = 0.004). Smoking rates and rate of detection by cancer screening did not differ between the two age groups. Because of the paucity of smokers among the younger female patients, causes of lung cancer other than smoking should be sought in younger patients. No difference was found in the stage of the disease at presentation, treatment methods and survival rates between the two age groups. It is suggested that the prognosis for patients with lung cancer under the age of 50 is not significantly worse than for those aged 50 years or older, as has been shown by several investigators.

Adult↗
PubMed1999

Detection of brain metastasis in potentially operable non-small cell lung cancer: a comparison of CT and MRI.

STUDY OBJECTIVE: To compare the usefulness of MRI and CT in the detection of brain metastases during preoperative evaluation and postoperative follow-up. DESIGN: A prospective and sequential comparison. PATIENTS AND METHODS: Of 332 patients with potentially operable non-small cell lung cancer who were free of neurologic signs and symptoms, brain CT was performed preoperatively on 155 patients (CT group) and brain MRI on 177 patients (MRI group). Patient characteristics in both groups were comparable. In 279 patients with complete resection of the primary lung tumor, intensive follow-up with CT and MRI was performed in the respective groups. The preoperative detection of brain metastases, postoperative intracranial recurrence rates, and characteristics of detected brain tumors were compared between the two groups. The survival of patients with brain metastases was also compared. RESULTS: From the first evaluation to 12 months after surgery for primary lung cancer, brain metastases were observed in 11 patients (7.1%) from the CT group and 12 patients (6.8%) from the MRI group. MRI detected brain metastases preoperatively in 6 of the 12 patients (3.4% of the total MRI group), whereas CT detected brain metastases preoperatively in 1 of the 11 patients (0.6% of the total CT group). MRI showed a tendency toward a higher preoperative detection rate of brain metastases than CT (p = 0.069). Furthermore, the mean (+/- SD) maximal diameter of the brain metastases was significantly smaller in the MRI group (12.8+/-9.1 mm) than in the CT group (20.3+/-7.0 mm) (p = 0.041). However, the median survival time and 2-year survival rate after treatment of detected brain metastases, respectively, were 10 months and 27% in the CT group and 17 months and 28% in the MRI group. There was no significant difference between the groups in survival time. CONCLUSIONS: Preoperative evaluation and intensive follow-up with MRI could facilitate early detection of brain metastases in patients with potentially operable lung cancer. However, further studies on detection and treatment of the metastatic tumors are considered necessary.

Adenocarcinoma↗
PubMed1999

Management of the hairline using a local flap in total reconstruction for microtia.

In cases of microtia with a low hairline, the manner in which hair is removed from the reconstructed auricle must be taken into consideration. This is one of the most common but difficult problems with reconstruction for microtia. The authors describe a new technique that uses a simple regional flap to resolve this problem. The hair-bearing skin in the estimated auricular region and its covering are removed using a local flap from the hairless mastoid region. This is done in the first stage of auricular reconstruction, the costal cartilage grafting is done in the second stage, and elevation of the auricle is done in the last stage. In 38 auricles of 36 patients who were treated from 1993 to 1995, eight auricles of eight patients were treated with this technique. In all cases, the hairless flap healed well, without vascular stasis or skin necrosis. In addition, no complications from using this technique occurred in the later stages of auricular reconstruction. With this technique, the skin of the flap provides a good texture and color match to the auricle. In addition, the skin of the flap has good elasticity for the cutaneous pocket for cartilage grafting. The harvested area of the flap can be hidden behind the reconstructed auricle. The authors initially wondered whether the marginal scar of the transposed flap's position in the auricle would be conspicuous. However, all of the scar became inconspicuous because it was positioned in the scaphoid fossa.

Adolescent↗
PubMed1998

Effects of ligation of the internal iliac artery on blood flow to the bladder and detrusor function in rat.

Ischaemia induced by atherosclerosis is a common cause of disorders in the elderly, including impairment of bladder function. To evaluate experimentally the effects of ischaemia on detrusor function, we performed infusion cystometry and evaluated the morphologic findings in the bladder of the rat. Blood flow to the bladder of the rat was evaluated with a Doppler flowmeter before and after the unilateral or bilateral ligation of the internal iliac arteries. Reevaluation was done at one and two weeks after surgery. Bladder function was studied by infusion cystometry performed in vivo under urethane anaesthesia. Finally, histological examination was performed. Blood flow at mid-dorsal wall of the control bladder was inversely related to intravesical volume. Unilateral or bilateral ligation of the internal iliac arteries decreased blood flow to the bladder, which showed a complete recovery two weeks postoperatively. Infusion cystometry of the ischaemic bladder with bilateral ligation of the internal iliac arteries demonstrated a decrease in voiding pressure, an increase in bladder capacity, and an increase in pressure at which micturition was initiated vs. the control. The bladder with unilateral ligation of the artery showed a decrease in voiding pressure, with no change in the other parameters. Histological examination indicated that the bilateral ischaemia and ischaemic side of unilateral ischaemia led to a degeneration of the mucosa, and severe oedema in submucosal and muscle layers one week postoperatively. Degeneration of smooth muscle was predominant at 2 weeks. Contralateral side of the unilaterally ischaemic bladder showed oedema and congestion of the submucosa and smooth muscle. Ligation of the internal iliac artery decreased blood flow to the bladder significantly, which resulted in smooth muscle degeneration. Consequently, in vivo voiding pressure was impaired in the ischaemic bladder.

Animals↗
PubMed1998

[Cystic thymoma without solid mass lesions on diagnostic imaging--a case report].

A 68-year-old man was referred to our hospital because of an abnormal shadow on a chest X-ray film. A chest CT scan and MRI demonstrated a cystic mass without solid lesions on the anterior mediastinum. The CT scan also showed that it was a well-defined and homogenous mass without contrast enhancement effect. 67Ga and 201T1 scintigrams showed no uptake in the mass. Needle aspiration cytology was performed, and there was no evidence of neoplasms. A thymic cyst was diagnosed, and then an operation was performed. At the operation, the cystic tumor was removed along with thymic tissues by a median sternotomy. On the cut section of the resected specimen, the tumor was found to be a cyst with small solid nodules on the wall. Pathologic examination revealed that the tumor was a cystic thymoma. We consider that patients with cystic tumors on the anterior mediastinum should obtain histopathologic diagnosis because of the difficulty in excluding neoplasms such as thymoma.

Aged↗
PubMed1998

[Huge localized mesothelioma of the diaphragm in a 17-year-old female--a case report with calculated tumor volume doubling time].

An operative case of localized mesothelioma of the pleura developed in a 17-year-old female was reported. She was admitted to our hospital complaining of right chest pain. A chest X-ray film showed a huge mass in the right lower field of the lung. After the embolization of the right inferior phrenic artery, which was the main feeder to the tumor, it was then successfully resected combined with the right diaphragm and the right lower lobe of the lung. Histologically, the tumor was diagnosed as benign localized mesothelioma (solitary fibrous tumor of the pleura). Further histological and immunohistochemical study revealed that it had developed from the connective tissue under the parietal mesothelium of the diaphragm. As chest roentgenograms had been undertaken during past two years, the tumor volume doubling time was calculated at 153 days. Despite the short tumor volume doubling time as like primary lung cancer, she is alive without recurrence 5 years after the operation.

Adolescent↗
PubMed1998

Inhibition of neutrophil-mediated acute inflammation injury by an antibody against interleukin-8 (IL-8)

Chemokines are a family of cytokines regulating the migration and functions of leukocytes in a cell-type specific manner. A prototype of C-X-C chemokines, interleukin-8 (IL-8), chemoattracts and activates neutrophils in vitro, and IL-8 concentrations in body fluids are markedly increased in several neutrophil-mediated acute inflammation. Moreover, we previously reported that the administration of a neutralizing antibody to IL-8 prevented neutrophil-mediated tissue injury, as well as neutrophil infiltration, in several animal disease models. These observations implicate IL-8 as a major mediator of neutrophil-mediated tissue injury. Furthermore, we recently showed that an anti-IL-8 antibody effectively prevented two models that are very relevant to clinical situations; endotoxemia-induced acute respiratory distress syndrome (ARDS)-like lung injury and cerebral reperfusion injury. These results raise the possibility that IL-8 is a novel target for therapeutic intervention in neutrophil-mediated acute inflammation.

Animals↗
PubMed1998

Long-term results of endarterectomy, anatomic bypass and extraanatomic bypass for aortoiliac occlusive disease.

Over the past 20 years, 214 patients in our hospital were operated on for aortoiliac occlusion, including an endarterectomy for 88 legs in 64 patients, an anatomic bypass for 178 legs in 105 patients, and an extraanatomic bypass for 51 legs in 45 patients. The extraanatomic group was older than the other two groups (70 years versus 64 years), and also showed a higher instance of critical ischemic symptoms than the other groups (49% versus 16%). The 10-year primary patency rate was 88% for an endarterectomy, 91% for an anatomic bypass, and 73% for an extraanatomic bypass. The 10-year survival rate was 71% for an endarterectomy, 49% for an anatomic bypass, and 24% for an extraanatomic bypass. The possible complications related to each surgical method included sexual dysfunction resulting from endarterectomy, and graft infection and anastomotic aneurysm in the prosthetic bypass. No ischemic symptoms in the donor limb were noted following an extraanatomic bypass. The selection of the appropriate surgical method for aortoiliac occlusion should thus be made after a careful review of the patient's general condition, the morphology of arterial occlusion, and the risk of possible complications for each type of surgery.

Adult↗
PubMed1998

A study of the concentration of orally administered sparfloxacin found in exudates from suture wounds beneath occlusive dressings.

The concentration of orally administered sparfloxacin (SPFX), an antimicrobial agent, in exudates from the suture wounds beneath occlusive dressings has been measured. Twenty-one patients who received oral therapy with 100 mg of SPFX prior to surgery and 200 mg/day of SPFX after surgery were studied. During the operations, the suture wounds were covered by occlusive film. 48h post-operation, wound exudates under the dressings were drawn and measured using high performance liquid chromatography. SPFX values were 0.801+/-0.340 microg/ml (mean+/-SD). The results suggest that wound exudates beneath the occlusive dressing have concentrations of SPFX high enough to prevent infection in most cases when administered orally.

Administration, Oral↗
PubMed1998

Acute mesenteric vascular occlusion: analysis of 39 patients.

OBJECTIVE: To study the factors that influence mortality and long term outcome of patients with acute mesenteric vascular occlusion. DESIGN: Retrospective study. SETTING: University hospital, Kanazawa, Japan. PATIENTS: Thirty-nine patients treated between 1978 and 1995 for acute mesenteric vascular occlusion. INTERVENTIONS: 34 patients underwent laparotomy. Bowel was resected in 29 patients, and primary anastomosis was done in 20. The occluded vessel was revascularised in 5 patients. MAIN OUTCOME MEASURES: mortality, short bowel syndrome and long term survival. RESULTS: 25 patients had arterial occlusions, and 8 venous. In the remaining 6, the occluded vessel was not identified. 11 Patients developed renal failure, 11 respiratory failure, and 10 disseminated intravascular coagulation (DIC). Twelve patients died within 30 days. The factors associated with early death were acidosis and high serum amylase activity. 9 Patients developed the short bowel syndrome. Survival was 49% at 1 year, and 34% at 5 years. CONCLUSION: Mortality was higher in patients with advanced peritonitis. Mesenteric revascularisation should be attempted to avoid the short bowel syndrome.

Adult↗
PubMed1998

Helical computed tomography diagnosis of pleural dissemination in lung cancer: comparison of thick-section and thin-section helical computed tomography.

Pleural dissemination in lung cancer was prospectively evaluated by helical computed tomography (CT), and the usefulness of thick-section CT (10-mm collimation; pitch 1) and thin-section CT (2-mm collimation; pitch 1) were compared. The study included 54 patients with pulmonary adenocarcinoma in whom plain chest radiographs showed no evidence of pleural effusion and in whom the primary lesion was seen to be contiguous with the pleural surface on thick-section CT. Thin-section CT was performed for evaluation of the costal, mediastinal, interlobar, and diaphragmatic pleural surfaces. Pathologic examination revealed pleural dissemination in 20 patients (8 resected, 12 nonresected). Pleural dissemination was diagnosed in 12 patients on thick-section CT, and in 20 patients on thin-section CT. False negatives occurred in ten and two patients, respectively. The same two patients were false positives by both methods. Accuracy was 78% for thick-section CT and 93% for thin-section CT, and sensitivity was 50% and 90%, respectively. Thin-section CT provided more useful information than thick-section CT for the evaluation of pleural dissemination in lung cancer.

Adenocarcinoma↗
PubMed1998

Nonsurgical correction of congenital auricular deformities in children older than early neonates.

It has been reported that nonsurgical correction of auricular deformities is not effective except in early neonates. We have succeeded in nonsurgical correction using thermoplastic splints for congenital auricular deformities on 50 ears of 45 patients without severe hypoplasia in children older than 1 year. Details of the types of ears we attempted to treat were 26 cryptotias, 5 lop ears, 5 Stahl's ears, 3 prominent ears, 3 shell ears, and 8 other miscellaneous conditions. The patients were between 1 and 14 years of age with an average age of 3.6 years. Our results were categorized as follows: excellent (the auricle was delicately corrected into a desirable form and satisfied the patient), improved (the auricle was corrected into a rough form that did not attain to a desirable shape and an irregular form still remained; however, its improvement satisfied the patient), recurrent (the auricle was initially corrected but the deformity recurred), not improved (the auricle was not corrected to the desired form and the result did not satisfy the patient), and gave up (the patient gave up before treatment could be completed). In our results, the average period of splint application was 2.1 months. In 27 of the 50 cases, the treated ears were excellent. Eleven ear cases showed improvement. Six cases showed recurrence. Three cases did not improve. Three patients gave up treatment. It is suggested that nonsurgical auricular correction is possible in almost all children, even if they are not early neonates, when corrections are made continuously and gradually.

Adolescent↗
PubMed1998

Reconstruction of congenital stenosis of external auditory canal with a postauricular chondrocutaneous flap.

We describe here a new surgical technique for treatment of congenital stenosis of the external auditory canal using a postauricular chondrocutaneous flap. Our technique prevents recurring stenosis by cartilage support and provides a sufficient extension of the canal. The chondrocutaneous flap is safely elevated, easily reaches the canal, and has ample blood supply. It is beneficial for its self-cleaning function that the remnant canal, which contains cerumen glands, is used as part of the reconstructed canal. Six patients with congenital stenosis of the external auditory canal were treated by our procedure. In these patients, three patients were treated by a postauricular approach and the others were treated by an endaural approach. All patients had very satisfactory results.

Child↗