Computer‐simulated bi‐directional alveolar distraction osteogenesis

Objectives: Computer‐based surgical planning allows surgeons to evaluate bone morphology in three dimensions and to perform accurate virtual surgery preoperatively. This study was performed to evaluate the feasibility of using preoperative surgical simulation to enhance the clinical outcome in patients undergoing bi‐directional alveolar distraction osteogenesis. Material and methods: Nine patients (mean age, 49 years; range, 20–61 years) with maxillary segmental alveolar defects following post‐traumatic atrophy or disuse atrophy after periodontal tooth loss were enrolled in the study. All patients were scheduled for implant placement. Three‐dimensional (3‐D) morphological evaluation and virtual bi‐directional distraction were performed with SimPlant CMF/OMS surgical simulation software (Materialise). In addition, use of an extraosseous bi‐directional distraction device (V2‐Alveolar Distraction System; Medartis AG) was evaluated during the 3‐D alveolar regeneration simulation and resulting augmentation. Results: Alveolar height regeneration and labial‐buccal augmentation were planned preoperatively using surgical simulation software. New bone formation with sufficient vertical augmentation of 5.8 mm was observed. As we encountered strong palatal inclination, the angulation required for labial‐buccal augmentation during active distraction was the maximum angulation of 40°, even greater than that required in the preoperative simulation of 23.9°. Furthermore, the labial‐buccal augmented angulation was gradually decreased to 11.2° at the time of implant placement. In all cases, implantation was successful at the well‐augmented sites, with sufficient primary stability after a 3‐month consolidation period. Conclusions: Preoperative 3‐D simulation is a potentially valuable tool for treatment of the morphologically complicated oral‐maxillofacial region. More realistic surgical simulations are anticipated with ongoing effort to collect and integrate clinical data into next‐generation software.     

Development Of The Human Mesencephalic Trigeminal Nucleus: A Morphometric Study

Anatomical development of the human mesencephalic trigeminal nucleus was assessed quantitatively and qualitatively, using serial sections of brains, with the help of a computer-assisted image-analyser. Five fetuses at 16, 18, 21, 23 and 27 weeks of gestation; five neonates at 30, 32, 33, 35 and 40 weeks of gestation; a two-month-old infant and a 63-year-old adult were studied. Morphometric analyses of the mesencephalic trigeminal nucleus revealed that orocaudal columnar length and neuronal areas gradually increased with gestational age. Diversity of neuronal areas appeared after 32 weeks of gestation, but neuronal numbers and shapes showed little change throughout prenatal and postnatal life.     

Comparison of the effects of in-vivo thermal ablation of pig liver by microwave and radiofrequency coagulation

Microwave and radiofrequency coagulation is frequently used for the treatment of hepatic tumors. However, differences between these types of therapy have not been clearly demonstrated so far. We performed both types of thermal ablative treatment on pig liver, and compared the size and shape of the coagulated areas produced. The effects of combining both treatments and interrupting hepatic blood flow were also evaluated. The liver of an anesthetized pig was thermally coagulated, with or without interruption of hepatic blood flow, using a needle electrode at 40 W for 150 s with 2450-MHz microwaves and/or with a 460-kHz radiofrequency current. The diameters of the coagulated areas in the liver were 20 ± 3 mm (mean ± SD; n = 4) after microwave coagulation and 28 ± 3 mm following radiofrequency coagulation when blood flow was not interrupted, whereas they were 31 ± 2 mm and 37 ± 3 mm, respectively, when blood flow was interrupted. When these treatments were combined sequentially, the diameters of the lesions were 43 ± 3 mm and 29 ± 2 mm with and without blood flow interruption, respectively. The ellipticity of the coagulated area, as measured by the largest-to-smallest ratio of its diameters, was 2.3 ± 0.4 after microwave coagulation and 1.1 ± 0.1 following radiofrequency coagulation. We conclude that radiofrequency coagulation produces a larger and more spherical coagulated area in the liver (P < 0.01) than does microwave coagulation. The lesion becomes larger (P < 0.05) with both treatments when hepatic blood flow is interrupted during the treatment. The sequential combination of these treatments produces a much larger lesion (P < 0.05) than that produced by either treatment alone.     

The optimal timing to resect pulmonary metastasis

OBJECTIVE: There is no criterion for the timing of surgical resection of pulmonary metastasis. In this study, we investigated the optimal period for pulmonary metastasectomy. METHODS: Between 2000 and 2005, 68 patients underwent complete pulmonary resection of metastatic cancer. Clinical prognostic factor in multivariate analysis was examined. RESULTS: The interval from pulmonary metastasectomy until subsequent recurrence and the interval from detection of pulmonary metastasis until pulmonary metastasectomy were independent prognostic factors. To investigate the relationship between the two characteristics, the 68 patients were divided into two groups according to the interval from lung metastasectomy until subsequent recurrence. Nineteen patients relapsed within 1 year after pulmonary metastasectomy (group A), while 49 patients did not relapse within 1 year (group B). The interval from detection of pulmonary metastasis until pulmonary metastasectomy was significantly shorter in group A than in group B (2.9 months vs 7.1 months, p=0.01). Based on these results, we divided the patients into two different groups and survival was compared. Significantly shorter survival was observed in the patients who underwent pulmonary metastasectomy within 3 months after detection of pulmonary metastasis (group X, n=35) than in those who underwent the surgery beyond 3 months (group Y, n=33). CONCLUSIONS: There were many cases of early relapse after metastasectomy when the interval from detection of pulmonary metastasis until pulmonary metastasectomy was short. Performing metastasectomy at least three months after detection of pulmonary metastasis may significantly improve the prognosis of patients.     

Role of substance P in viral myocarditis in mice

Substance P (SP) is widely expressed in the central nervous system and in peripheral tissues such as myocardial nerves. We examined SP in viral myocarditis in mice induced by encephalomyocarditis virus (EMCV). Localization of SP in the hearts was examined immunohistochemically, and concentrations of SP in hearts and sera were measured by enzyme immunoassay. Substance P levels and density of SP-containing cells in murine hearts on day 6 after EMCV inoculation were decreased compared with those in normal controls. There was a negative correlation between SP levels in the hearts and ratio of heart weight to body weight of the mice at 6 days. Circulating SP levels were decreased in mice on day 6 after EMCV inoculation, and further decreased on day 14. Substance P in hearts and sera is decreased in viral myocarditis in mice, suggesting that SP may play a role in the pathogenesis of viral myocarditis, and that interaction of the neuropeptide nervous system and mast-cell immune system is important in the pathogenesis of viral myocarditis.     

EFFICACY OF AZATHIOPRINE IN MILD OR MODERATE RELAPSE IN CROHN'S DISEASE: CLINICAL AND ENDOSCOPIC EVALUATION

Aim: The present study was aimed at evaluating the efficacy of azathioprine (AZA) in patients with active and relapsing Crohn's disease (CD) and the usefulness of endoscopy in this evaluation. Methods: The 53 patients with active CD treated with AZA at our hospital were subjected to the following retrospective analysis: (i) evaluation of the clinical efficacy of AZA through comparison of the Crohn's disease activity index (CDAI); (ii) analysis of the relationship of the clinical efficacy to the difference in the mean corpuscular volume (MCV); (iii) evaluation of mucosal healing through analysis of the scores of the endoscopic findings in 16 patients; and (iv) analysis of the relapse rate. Results: (i) Among the 53 patients, treatment was rated as having induced complete remission in 22.6%, as being effective in 41.5%, and as being ineffective in 13.3% of patients. The treatment was discontinued in 22.6% of patients. (ii) The post‐treatment MCV was significantly increased after treatment. (iii) When the ulcer score estimated after treatment was compared with that before the start of treatment, a significant improvement of the score was noted. (iv) When the non‐relapse rate after AZA therapy was calculated in the 41 patients followed up for 12 months, it was 84.8%. Conclusion: AZA was shown to cause endoscopic mucosal healing as well as clinical efficacy. In the present study, it was inferred that the efficacy of AZA therapy in CD patients is manifested clinically first and that mucosal healing is an effect that occurs later.