Prosthetic replacement of the hip in dogs using bioactive bone cement

Total hip arthroplasties were performed in dogs using bioactive bone cement consisting of silane treated CaO-MgO-SiO2-P2O5-CaF2 glass powder as the filling particles and bisphenol-a-glycidyl methacrylate based resin as the organic matrix, and the outcomes were compared with the results of polymethylmethacrylate bone cement. The mechanical properties of the bioactive bone cement were stronger than the mechanical properties of polymethylmethacrylate bone cement. The bonding strength of the bioactive bone cement to bone in dogs' femora increased with time, reaching 4.7 MPa at 6 months, whereas that of polymethylmethacrylate bone cement did not increase, remaining at 1.0 MPa. Results of histologic examination showed direct bonding between the bioactive bone cement and bone, and the bony trabeculae around the cement mantle grew with time. However, in polymethylmethacrylate bone cement, an intervening soft tissue layer was evident at the bone cement interface. Direct bonding of the bioactive bone cement at the interface through an apatite layer of 30 microm in thickness was shown through observation with the scanning electron microscopy. Using this bioactive bone cement in clinical settings may help alleviate serious problems associated with cemented total hip arthroplasty, such as aseptic loosening of the implant and mechanical failure of the bone cement.

Multiple thoracic disc herniations: case report and review of the literature

The incidence of intervertebral disc herniation in the thoracic region of the spine is much less than in the cervical or lumbar areas, and multiple thoracic disc herniations are rare. We described a 33-year-old man with two-level thoracic disc herniation, who exhibited features of spinal cord compression. Magnetic resonance imaging and computed tomographic myelography demonstrated anterior compression of the spinal cord due to disc herniation at T4/5 and T7/8 levels. Through an anterolateral approach, these discs were removed and interbody fusion was performed using autogenous bone grafts. Excellent results were obtained.

Correction of kyphotic deformity of the cervical spine in ankylosing spondylitis using general anesthesia and internal fixation

Surgical correction of kyphotic deformity of the cervical spine caused by ankylosing spondylitis is usually done using local anesthesia to prevent undue spinal cord compression and paralysis followed by a sudden-extension maneuver. We report a case of kyphotic deformity that was corrected while the patient was under general anesthesia. To prevent cord compression and paralysis and to obtain an accurate and gradual correction, we used a Hartshill rod prebent to the desired angle, and correction was done by tightening sublaminar wires on the rod until the lamina made full contact with it. Somatosensory evoked potential and wake-up tests were also performed. Our successful result shows that correction of kyphotic deformity of the cervical spine in ankylosing spondylitis can be done more accurately and without discomfort using the present method.

Deficiencies of automatic endoscopic reprocessors: a method to achieve high-grade disinfection of endoscopes

BACKGROUND

We show that disinfection using the automatic endoscopic reprocessor is not complete and propose a method for high-grade disinfection of endoscopes.

METHODS

We used an automatic endoscopic reprocessor, Pyser System 83, and 2% glutaraldehyde. After each endoscopic procedure, the endoscopes were divided into three groups. Endoscopes in group A were washed only by the reprocessor. Group B endoscopes were washed by the reprocessor after the connectors were soaked in glutaraldehyde for 5 minutes. The channels, valves, connecting sections of group C endoscopes, and the connectors of the machine were sprayed with glutaraldehyde before machine-washing. Swabs were taken from all 13 parts of each endoscope and machine for microbiologic culture.

RESULTS

Six endoscopes were positive, cumulatively, for bacterial contamination in group A. Among group B endoscopes, one remained contaminated. No endoscope was positive in group C. The difference between group A and C was statistically significant (p < .05).

CONCLUSIONS

Machine washing by automatic endoscopic reprocessors may not achieve complete disinfection. Additional procedures are necessary. High-grade disinfection of the connectors is critical. Disinfection of the interface between the connectors is important.

A method of evaluating drug efficacy by statistical analysis of healing speed of peptic ulcer

At present, the evaluation of anti-ulcer drugs is generally accomplished simply by calculating the cumulative healing rate at a certain point of time during treatment, which does not implicate any analysis of the healing speed of the ulcer. If the cumulative healing rate of an ulcer is expressed as a function of drug administration time, t, then it will be possible to calculate parameters concerning the healing speed of ulcers and thus evaluate drug efficacy as the time series analysis of the cumulative healing rate. A new method of evaluating anti-ulcer drugs by a statistical analysis of healing speed is proposed. A non-linear regression analysis was performed between two variables, t (time of drug administration: week) and y (non-healing rate: %), to obtain the exponential function y = Ae-kt. The theoretical values calculated from the exponential equation were in close proximity to the observed values. With this analysis, four parameters concerning the healing speed were defined, namely the healing rate constant, the initiation time of healing, the half-life of non-healing rate and the time necessary for 50% healing. With this method, the efficacy of drugs on peptic ulcer healing was dynamically analysed, the non-healing rate (y) being expressed as an exponential function of length of time (t) of treatment, thus obtaining digital parameters for healing speed.

[A case of right upper lobe carcinoma with lung torsion changed in position]

A 71-year-old man with a pulmonary carcinoma had torsion of the right upper lobe of the lung. A chest radiogram showed change of the opacified lobe in position. At right thoracotomy, we found that the atelectatic right upper lobe occupied with a giant tumor moved freely in the right thoracic cage due to the defect of parenchymal bridge between the contiguous lobes. Though lung torsion is a rare event, it might be kept in mind as a complication of malignant tumors or life-threatening lung infarctions.

Suction/irrigation for deep wound infection after spinal instrumentation: a case study

Deep wound infection after spinal instrumentation is a serious complication that is difficult to treat without removing the instruments and bone graft. Debridement and suction/irrigation is an effective method of treatment in these cases. It was performed on six patients in our department who developed this complication between 1985 and 1994. Four patients with early post-operative infection were cured by this method without removing the instruments and bone graft, and two patients with delayed post-operative infection were cured by this method with instrument removal. Debridement and suction/irrigation is a useful method of treatment for both groups of deep wound infection and gives good results when performed soon after infection onset together with additional antibiotic therapy.

Assessment of the course and variations of the hepatic artery in bile duct cancer by intraductal ultrasonography

BACKGROUND

We evaluated the course and variations of the hepatic artery in bile duct cancer using intraductal ultrasonography (IDUS).

METHODS

IDUS was used to demonstrate the course of the hepatic artery preoperatively in 20 patients with extrahepatic bile duct cancer, and the image was compared with angiographic and surgical findings.

RESULTS

IDUS was able to assess tumor invasion to the main branch of the right hepatic artery in all cases. However, it demonstrated only three cases in the left hepatic artery and four cases in the proper hepatic artery. When the hepatic artery indicated re-entry or bifurcation on the IDUS image, the proximal portion of re-entry or bifurcation was established as the proper hepatic artery, but when it showed neither re-entry nor bifurcation it was established as the right hepatic artery.

CONCLUSIONS

IDUS demonstrated the main branch of the right hepatic artery in all cases, but was not useful for demonstration of the left and proper hepatic arteries. Correct assessment of re-entry and bifurcation was essential on IDUS images for making the distinction between the right hepatic artery and the proper hepatic artery.

Assessment of pancreatic parenchymal invasion by bile duct cancer using intraductal ultrasonography

BACKGROUND AND STUDY AIMS

This study was performed to clarify the diagnostic accuracy of intraductal ultrasonography (IDUS) in assessing pancreatic parenchymal invasion by bile duct cancer.

PATIENTS AND METHODS

Preoperative assessment of pancreatic parenchymal invasion was carried out by IDUS via a percutaneous tract or a transpapillary route in 18 patients with extrahepatic bile duct cancer. Various probes with diameters of 1.4, 2.0, 2.4, 2.6 and 3.2 mm, and frequencies of 7.5, 15, 20 and 30 MHz were used. All patients underwent angiography and endoscopic ultrasonography (EUS). In the first six cases, IDUS and EUS images were analyzed retrospectively without knowledge of the operative outcome or the results of other imaging tests. In the subsequent 12 cases, the IDUS und EUS images were prospectively reviewed prior to surgery. The diagnostic accuracy of IDUS was compared with angiography and EUS by means of a histopathological examination of the resected specimens.

RESULTS

The accuracy of IDUS, EUS, and angiography in assessing pancreatic parenchymal invasion was 100%, 78% and 61%, respectively. However, IDUS could not assess pancreatic capsular invasion. The accuracy of IDUS in assessing horizontal tumor extension to the intrapancreatic bile duct and to the hepatic side was 83% and 72%, respectively.

CONCLUSIONS

IDUS proved useful for assessing the extension of cancer invasion to the pancreatic parenchyma, but not to the pancreatic capsule or mucosal surface.

Confirmation of a "safety zone" by intraoperative cholangiography during laparoscopic cholecystectomy

BACKGROUND

Creating a "safety zone" during laparoscopic cholecystectomy is defined as dissection of the cystic duct as close as possible to the gallbladder.

METHODS

In 29 out of 802 cases in which laparoscopic cholecystectomy was difficult to perform due to uncertainty about the orientation of Calot's triangle, intraoperative cholangiography was performed, using a titanium clip as a marker that designated the safety zone. The distance between the clip and the common hepatic duct or the common bile duct could be determined by evaluation of two intraoperative cholangiograms taken in different orientation.

RESULTS

If the clip was located in the safety zone, and was distant from the common hepatic duct or common bile duct, the safety of preparation around the clip was ensured. No complication was encountered in these cases with this method. Eventually, no biliary tract injury was experienced, and the overall conversion rate to open cholecystectomy was only 0.4% (3 of 802 consecutive cases).

CONCLUSIONS

This method of confirming the safety zone by intraoperative cholangiography is a useful procedure for avoiding inadvertent injury to the biliary tract.

[Can we know the frequency of true late adverse reactions to nonionic contrast media?: Late adverse reactions due to factors other than contrast media]

We investigated the frequency and causative factors of symptoms unrelated to contrast media (false late adverse reactions) among patients who were evaluated as having late adverse reactions to contrast media. The nature and frequency of complaints stated by each 200 of patients who underwent plain CT scans and enhanced CT scans were evaluated. In the plain CT group, three patients showed false late adverse reactions. The frequency was 2.6% among respondents and 1.5% in the population. These symptoms encompassed psychological effects and diseases that developed after CT scanning. It is difficult to detect only true late adverse reactions, because of survey bias.

Laparoscopic transcystic cholangioscopic lithotripsy for common bile duct stones during laparoscopic cholecystectomy

BACKGROUND AND STUDY AIMS

Following the recent introduction of laparoscopic cholecystectomy (LC) for cholecystolithiasis, treatment of concomitant common bile duct (CBD) stones has been evaluated by using laparoscopic choledochotomy, a transcystic approach, or by means of endoscopic sphincterotomy (ES) before or after LC.

PATIENTS AND METHODS

During laparoscopic cholecystectomy, we attempted lithotripsy of CBD stones using laparoscopic transcystic cholangioscopy with lithotripsy (LTCL), in 70 patients out of 950 laparoscopic cholecystectomies. Preparatory tests included laboratory values, ultrasound, and performance of endoscopic retrograde cholangiography (ERC) with placement of a nasobillary tube (without sphincterotomy).

RESULTS

Introduction of the cholangioscope into the CBD was successful in 65 patients (92.9%) and CBD clearance was completely achieved by LTCL alone in 51 (78.5%). The overall success rate was therefore 73%. The remaining 19 cases required postoperative procedures such as extracorporeal shock-wave lithotripsy without ERC or ES (successful in all). The average hospital stay period was 9.4 days for patients in whom CBD clearance was achieved by LTCL alone. This period did not differ significantly from that of patients who underwent LC alone (8.4) days. The operation time was about 70 minutes longer for the LTCL group (total time 174 minutes on average) than for the LC group (107 minutes). We did not observe any series complications during or after LTCL (mean follow-up period: 34 months).

CONCLUSION

LTCL in combination with LC allows shortening of the hospital stay and a swift return to work for patients with CBD stones. This procedure also preserves the function of the sphincter of Oddi, so that the longterm prognosis for patients is likely to be very good.

Distribution of inflammation and atrophy in the stomach of Helicobacter pylori-positive and -negative patients with chronic gastritis

OBJECTIVES

To investigate the extent of inflammation and atrophy in the stomach of Helicobacter pylori-positive and -negative patients with chronic gastritis.

METHODS

Endoscopy with biopsies from the lesser curvatures of the antrum, angulus, middle body, and the greater curvature of the middle body of the stomach was performed in 59 patients with histologically confirmed chronic gastritis. The extent of atrophic gastritis was assessed endoscopically as well histologically. H. pylori status was assessed by histology as well as enzyme-linked immunosorbent assay. The histological severity of chronic and acute inflammation, glandular atrophy, and intestinal metaplasia was assessed according to the Sydney system.

RESULTS

In H. pylori-positive patients, H. pylori was evenly distributed throughout the stomach when the extent of atrophic gastritis was limited to the antrum and the lesser curvature of the body, but disappeared from the antrum of patients with more extensive atrophic gastritis. The severity of acute and chronic inflammation at the greater curvature of the body increased with the extension of atrophic gastritis. In H. pylori-negative patients, the severity of chronic inflammation at the greater curvature of the body was significantly higher in patients with extensive atrophic gastritis than in those with a lesser extent of atrophic gastritis.

CONCLUSION

At the greater curvature of the body, the development of atrophy is closely associated with the increase in the severity of inflammation, which is more marked in H. pylori-positive patients.

The usefulness of ultrasonic microprobe imaging for endoscopic variceal ligation

OBJECTIVES

This study investigated whether ultrasonic microprobe (UMP) imaging was useful in judging the therapeutic effect of endoscopic variceal (EVL) on varices as well as assessing varices and surrounding vessels before and after EVL.

METHODS

UMP imaging was performed repeatedly safely and easily via the biopsy channel of an endoscope in 20 patients with esophageal varices. Using this modality in combination with our method of "intensive ligation," we treated esophageal varices successfully.

RESULTS

Before EVL, UMP imaging displayed esophageal varices, periesophageal collaterals, and the azygous vein as echo-free lumens. In 15 of 20 patients, UMP imaging clearly detected the perforating vein, one of the optimal ligation sites for EVL, connecting the varix and collateral vein. Just after EVL, UMP imaging revealed a hyperechoic change ("snow ball" sign or "snow channel" sign), indicating blood flow stasis in the esophageal varices. On subsequent EVL, UMP imaging showed the cross-sectional area of varices was undetectable (occluded) or partially detectaable. After repeated EVL (2.9 treatment sessions on average), UMP imaging, as well as endoscopy, indicated that almost all varices were eradicated (undetectable). However, UMP imaging demonstrated that neither collaterals nor the azygous vein had significantly changed in size.

CONCLUSIONS

This modern diagnostic modality provided a clinical adjunct to current endoscopy when observing esophageal varices and surrounding vessels before and after EVL to determine the need for additional therapy.

Gastritis in the Japanese stomach

Endoscopic studies of Japanese patients with gastritis have revealed the existence of an endoscopic atrophic border that marks the transition between non-atrophic gastritis and atrophic gastritis, and between fundic glands and pyloric glands. Marked changes in cell type, gastritis activity, atrophy and density of Helicobacter pylori infection occur across this border. Gastritis appears to extend from the antrum to the corpus more quickly in Japanese patients than in patients from other populations. Infection with H. pylori may be an important factor influencing the rate of progression of gastritis in Japanese patients.

Assessment of portal vein invasion by bile duct cancer using intraductal ultrasonography

BACKGROUND AND STUDY AIMS

We recently reported on the contribution of intraductal ultrasonography (IDUS) to the regional staging of bile duct cancer, and we present here the first detailed study of the value of IDUS in assessing the portal vein invasion by bile duct cancer.

PATIENTS AND METHODS

Preoperative assessment of portal vein invasion was performed by IDUS via a percutaneous tract or via transpapillary route in 18 patients with extrahepatic bile duct cancer. Various probes, with diameters of 1.4, 2.0, 2.4, 2.6, and 3.2 mm, and frequencies of 7.5, 15, 20, and 30 MHz, were used. All patients additionally underwent endoscopic ultrasonography (EUS) and angiography. In the first six cases, the IDUS and EUS images were analyzed retrospectively without the knowledge of operative results or the other imaging tests. In the remaining 12 cases, IDUS and EUS images were prospectively reviewed prior to surgery, without knowledge of the angiographic findings. The gold standard for the results of IDUS, EUS and angiography was the histopathological findings in 17 resected tumors, and the intraoperative findings in one patient who did not undergo resective surgery.

RESULTS

IDUS was able to demonstrate the portal vein in all cases. Its accuracy in diagnosing portal vein invasion was 100% for all locations. EUS was useful in assessing portal vein invasion at the middle and distal bile duct (the accuracy was 91%), but was not useful in assessing invasion at the proximal bile duct (the accuracy was 57%).

CONCLUSIONS

IDUS proved useful for assessing the extension of cancer invasion into the portal vein, even in proximal bile duct tumors.

Assessment of hepatic artery invasion by bile duct cancer using intraductal ultrasonography

BACKGROUND AND STUDY AIMS

This study was performed to clarify the diagnostic accuracy of intraductal ultrasonography (IDUS) in assessing hepatic artery invasion by bile duct cancer.

PATIENTS AND METHODS

Preoperative assessment of hepatic artery invasion was performed by IDUS via a percutaneous tract or the transpapillary route in a total of 22 patients with extrahepatic bile duct cancer. The probes used had a diameter of 1.4, 2.0, 2.4, 2.6, and 3.2 mm, and frequencies of 7.5, 15, 20, and 30 MHz. In the first six cases, IDUS images were analyzed retrospectively with no knowledge of the operative results or of the other imaging tests. In the following 16 cases, the IDUS images were prospectively reviewed prior to surgery without knowledge of the angiographic findings. The diagnostic accuracy of IDUS was compared with angiography in all cases, with the histopathological results in 20 resected cases, and with the intraoperative findings in two cases with only surgical exploration.

RESULTS

IDUS was able to demonstrate the right hepatic artery in all cases, and its accuracy in diagnosing right hepatic invasion was 100%. However, IDUS was able to visualize the proper hepatic artery in only four cases (18%), and the left hepatic artery in only three cases (14%), respectively. IDUS could not visualize the area outside of the hepatoduodenal ligament, because of its low penetration depth.

CONCLUSIONS

IDUS proved useful for assessing the extension of bile duct cancer invasion into the right hepatic artery. However, IDUS did not sufficiently demonstrate the proper hepatic artery and the left hepatic artery for diagnosing vascular involvement.

Laparoscopic cholecystectomy in the elderly: analysis of pre-operative risk factors and postoperative complications

A retrospective study was conducted of two groups of patients over (group 1, n = 57) and under (group 2, n = 655) the age of 70 years who underwent laparoscopic cholecystectomy (LC). The pre-operative physical status and systemic complications, operation time, postoperative complications, postoperative hospital stay and other clinical features of the two groups were compared. The incidence of pre-operative complications in group 1 was significantly higher than that in group 2 (P < 0.05). Postoperatively no severe complication was found in any patient. Group 1 showed significantly prolonged operation time and postoperative hospital stay compared with group 2 (P < 0.05). The difference between the groups in the intra-operative treatment time and postoperative treatment is attributed to the greater prevalence of common bile duct stone in group 1 as there was little difference between the groups in the postoperative recovery after exclusion of these patients. No pulmonary complications, which are associated with LC, were observed; the postprocedure pain was slight and the period of bedrest was short. If complications associated with pneumoperitoneum can be prevented, this surgery is an excellent measure to improve the quality of life of even elderly patients with cholecystolithiasis.

Dual therapy with lansoprazole and clarithromycin for eradication of Helicobacter pylori

AIM

To evaluate the eradication of Helicobacter pylori by therapy with a combination of 60 mg lansoprazole and 800 mg clarithromycin.

PATIENTS AND METHODS

In an open therapeutic trial, 30 H. pylori-positive patients with active ulcer disease took 30 mg lansoprazole twice a day and 400 mg clarithromycin twice a day for the first 2 weeks, followed by 30 mg lansoprazole once a day for 4-6 weeks. Endoscopy was performed both before and at the end of therapy, and 4 weeks after the end of the therapy. H. pylori was detected by using a combination of smear, culture and tissue sections.

RESULTS

Complete pain relief occurred within 3 days in all patients and all ulcers were healed by the end of the therapy. The H. pylori clearance rate was 83.3% and the eradication rate was 73.3%. A minor side effect (metallic taste) was reported by only one patient (3.3%).

CONCLUSIONS

Therapy with a combination of 60 mg lansoprazole and 800 mg clarithromycin is efficacious in the eradication of H. pylori and has the advantage of a low incidence of side effects and quick pain relief for patients with active ulcers.