Effects of sciatic neurectomy on the femur in growing rats: Application of peripheral quantitative computed tomography and Fourier transform infrared spectroscopy

The effects of unilateral sciatic neurectomy (USN) on the development of the femur were studied in 15 growing Wistar-derived rats (age, 5 weeks). The rats were divided into four groups: USN-operated group (right femur), USN-nonoperated group (left femur), sham-operated group (right femur), and sham-nonoperated group (left femur). Bone mineral density (BMD), bone mineral content (BMC), bone area, periosteal circumference, and endosteal circumference were measured by peripheral quantitative computed tomography (pQCT) and the mineral/matrix ratio was evaluated by Fourier transform infrared spectroscopy (FTIR). The USN-operated group showed a significant decrease in cortical BMC, bone area, and periosteal circumference compared with the other groups (P < 0.05). The cortical BMD did not vary significantly between the groups. In the cancellous bone, the USN-operated group showed a significant decrease in BMD and BMC at the metaphysis compared with the other groups (P < 0.05). The mineral/matrix ratio of the cortical bone did not differ significantly between the USN-operated and USN-nonoperated groups. These results suggest that in cortical bone, USN inhibits periosteal bone formation but has no significant effect on the mineral/matrix ratio of cortical bone in femurs. In cancellous bone, USN induces bone loss at the metaphysis. Received: Nov. 19, 1998 / Accepted: Feb. 12, 1999     

Transthoracoscopic needle biopsy for indeterminate lung nodules

Background: The usefulness of transthoracoscopic needle biopsy for preoperatively indeterminate intrapulmonary nodules was evaluated. Methods: Thoracoscopy was performed on 38 patients with pulmonary solitary nodules suspected to be primary lung carcinomas. When the nodule was localized by simple observation or tactile sensor, a biopsy specimen of the tumor was obtained by a biopsy needle introduced through a trocar. Results: The nodules were 7 to 55 mm in diameter. All were located in the peripheral region of the lung. Biopsy specimens were obtained even from 17 nodules with no associated pleural changes. By cytology, all the malignant tumors were precisely diagnosed, 29 as primary lung cancers and 3 as metastatic lung neoplasms. Five of the remaining six benign nodules were not precisely diagnosed. However, they were cytologically classified as class I. Conclusions: Transthoracoscopic needle biopsy is feasible for diagnosing small intrapulmonary nodules, particularly those of malignant neoplasms. As compared with thoracoscopic excisional biopsy, transthoracoscopic needle biopsy saves time and may reduce the possibility of tumor dissemination during the procedure. Received: 14 March 1997/Accepted: 31 May 1997     

Safe creation of pneumoperitoneum using an optical trocar

The blind insertion of the Veress needle and the first trocar may cause serious complications. Therefore, many surgeons perform a minilaparotomy to safely position the first trocar. However, especially in obese patients, the dissection may be difficult and time consuming. As an alternative, optical trocars can be safely positioned under direct visualization. We report on our experience with the Optiview trocar in 200 patients and describe our preferred insertion technique. In our opinion, optical trocars are safe and easy to handle, offering several advantages over the use of the Veress needle and the minilaparotomy. Received: 19 February 1998/Accepted: 28 May 1998     

Characteristics of bone mineral density and soft tissue composition of obese Japanese women: Application of dual-energy X-ray absorptiometry

We studied the characteristics of bone mineral density (BMD) and soft tissue composition in obese Japanese women using dual-energy X-ray absorptiometry. Eighty-nine women, aged 45–85 years, were divided into three groups according to their body mass index (BMI): a thin group (n = 38; BMI < 21), a standard weight group (n = 31; BMI, 21–25), and an obese group (n = 20; BMI ≥ 25). The mean BMD of the second to fourth lumbar vertebrae and BMD of the lumbar spine, thoracic spine, pelvis, legs, and ribs of the thin group were significantly lower than those of the standard weight group or the obese group (P < 0.05), whereas no significant difference in total body BMD was observed among the three groups. There was a significant difference in total and regional fat mass among the three groups (P < 0.05). Lean mass of legs and total lean mass showed a significant difference between the thin group and the obese group (P < 0.05). The results showed that obesity was associated with higher BMD of weight bearing-bones and ribs, high total and regional fat mass, and high lean mass of bilateral legs and total lean mass. We suggest that obesity may contribute to the prevention of bone loss of weight-bearing bones and ribs and muscular atrophy of the legs. Received: Sept. 30, 1998 / Accepted: Dec. 10, 1998     

Bone mineral density in patients with ossification of the posterior longitudinal ligament in the cervical spine

Bone mineral density (BMD) has not been clearly determined in patients with ossification of the posterior longitudinal ligament (OPLL) in the cervical spine. BMD in patients with OPLL was measured in the third vertebral body in the lateral projection and in the distal part of the radius in the anteroposterior projection using dual-energy X-ray absorptiometry (DXA). Patients with OPLL had significantly higher BMD than healthy controls in both the lumbar spine and radius. Observing BMD by gender and age group, high BMD was recognized especially in female patients over 60 years of age. Significantly increased BMD was observed in patients with ankylosing spinal hyperostosis (ASH) in addition to OPLL. These findings suggest that patients with OPLL may tend to develop systemic hyperostosis, leading to the pathological ectopic ossification observed in OPLL. Received: July 7, 1998 / Accepted: March 17, 1999     

Localization of the nonpalpable colonic lesion with intraoperative ultrasound

Localization of an nonpalpable colonic lesion at the time of colectomy usually requires intraoperative colonoscopy. The use of ultrasound to locate the lesion has not been described. A soft bowel clamp is placed above the expected location of the lesion and a catheter placed in the anus. Saline is then instilled into the colon and rectum. The lesion is located by ultrasound scan of the fluid filled colon with the probe placed on the serosal surface. Refinement of the technique was performed on resected colonic specimens. An in vivo trial was then performed with rapid and accurate localization of the lesion for resection. Intraoperative ultrasound of the colon can accurately localize nonpalpable colonic lesions and is an alternative to currently available techniques of localization. Received: 10 December 1997/Accepted: 11 March 1998