A new method for monitoring the cerebrovascular response to acetazolamide using 99mTc-DTPA-HSA.

We developed a new method for monitoring the cerebrovascular response to acetazolamide using technetium-99m diethylenetriaminepentaacetic acid human serum albumin (99mTc-DTPA-HSA). We infused 740 M Bq (20 mCi) of 99mTc-DTPA-HSA intravenously and carried out dynamic scanning of the anterior view of the head for 50 minutes. Ten minutes after the start of scanning, 1,000 mg of acetazolamide was injected intravenously. In three normal volunteers, the radioactivity in brain increased for an average of 8 minutes after the injection of acetazolamide and then remained relatively stable. The average of dilatation index [(peak count/the count just before acetazolamide injection-1)x 100] was 16.1. Our method enabled us to observe vasodilation caused by acetazolamide straight, and may be of value in assessing cerebral perfusion reserve easily and quantitatively.     

COX-2+ myofibroblasts may play a key role in marked stromal fibrosis in strictured colorectal carcinomas

AIMS: To elucidate the mechanism of marked stromal fibrosis in strictured colorectal carcinomas (SC) that cause complete ileus. METHODS AND RESULTS: Sixteen cases of SC and 29 cases of non-strictured colorectal carcinoma (NSC) were studied. These carcinomas showed similar clinicopathological features except for bowel stricture. The stricture index (SI) showing the degree of bowel stricture was 59.8 +/- 12.1% in SC versus 20.8 +/- 24.6% in NSC (P < 0.001). The fibrosis index (FI), defined to reflect the extent of stromal fibrosis, was 56.3 +/- 8.8% in SC versus 21.9 +/- 10.6% in NSC (P < 0.001). COX-2+ myofibroblasts were detected in 13 cases (81.3%) in SC versus eight cases (27.6%) in NSC (P < 0.01). The COX-2+ myofibroblast density was 276.7 +/- 181.1 cells/mm(2) in SC versus 26.6 +/- 52.7 cells/mm(2) in NSC (P < 0.001). When all cases were divided into two groups with and without COX-2+ myofibroblasts, the SI was 48.8 +/- 19.1% in those with COX-2+ myofibroblasts versus 24.8 +/- 29.3% in those with COX-2- myofibroblasts (P < 0.001). CONCLUSION: COX-2+ myofibroblasts may play an important role in extensive bowel stricture in colorectal carcinomas.     

Correlation between echocardiographic superior vena cava flow and short-term outcome in infants with asphyxia

Objectives

To assess the relationship between superior vena cava (SVC) flow and short-term outcome in infants with perinatal asphyxia.

Methods

Infants in sequence born after more than 35 weeks of gestation who had been hospitalized at the NICU and normal neonatal wards of Wakayama Medical University between May 2005 and September 2010 were recruited for this observational cohort study. The study eligibility criterion was the presence of perinatal asphyxia, as evidenced by abnormal fetal heart rate monitoring and an Apgar score of 7 or less at 1 min or need for resuscitation using positive pressure ventilation. SVC flow was measured in the first three days of life by Doppler echocardiography as described by Kluckow and Evans. Short-term outcome was defined as poor if MRI demonstrated bilateral lesions of the basal ganglia and thalamus and/or multicystic encephalomalacia due to hypoxic ischemia.

Results

In the head cooling group, SVC flow in infants with a good outcome was lower than that in infants with a poor outcome at 12 h (36.9 ± 7.7 vs 113.4 ± 42.4 ml/kg/min (p = 0.01)), 24 h (75.2 ± 25.3 vs 155.6 ± 45.7 ml/kg/min (p = 0.03)), and 48 h (92.5 ± 34.2 vs 161.1 ± 46.7 ml/kg/min (p = 0.04)) after birth. SVC flow decreased promptly after introduction of head cooling in infants who had a good outcome, whereas it increased gradually after head cooling in those who had a poor outcome.

Conclusion

We speculate that regulation of brain circulation is disrupted in infants with asphyxia who show a poor outcome.     

Cytomegalovirus reactivation in patients with multiple myeloma

The introduction of novel antimyeloma agents has improved the outcome of multiple myeloma (MM) dramatically. However, it has also led to an increasing incidence of Herpesviridae family virus infections, including a high incidence of post‐transplant cytomegalovirus (CMV) reactivation after treatment with novel agents. We herein retrospectively assessed the CMV reactivation in all 120 newly diagnosed patients with MM consecutively seen and treated at our hospital. CMV antigenemia tests were ordered in 58 patients depending on the clinical context, and the incidence of CMV reactivation and proven/suspected CMV disease requiring antiviral therapy was 20% (24 of 120) and 11% (13 of 120) respectively, including those without stem cell transplantation (SCT). The clinical and laboratory characteristics of these patients were compared with those in 34 CMV antigenemia‐negative (CMV‐negative) patients. Patients with extramedullary disease or a low absolute lymphocyte count (ALC) had a higher risk of developing CMV reactivation. In addition, the median duration from the time of MM diagnosis to CMV reactivation was 5.0 months. These results suggest that, regardless of whether or not undergoing SCT, elderly patients with MM receiving novel agents should be monitored for CMV reactivation to allow for the timely diagnosis and treatment, especially for those with extramedullary disease.     

Evaluation of pre-surgical models for uterine surgery by use of three-dimensional printing and mold casting

We propose an approach to supporting pre-surgical planning for the uterus by integrating medical image analysis and physical model generation based on 3D printing. With our method, we first segment the patient-specific anatomy and lesions of the uterus on MR images; then, we create a 3D physical model, an exact replica of the patient’s uterus in terms of size and softness, with transparency for easy observation of the internal structures of the uterus. In our experiments, we created pre-surgical models of hysterectomy for five patients who had been diagnosed to have uterine endometrial cancer. An experienced radiologist, the surgeons, and all of the patients cooperated in our experiment for carrying out subjective evaluations of the usefulness of our model. The accuracy of the physical models was evaluated quantitatively by comparison between the MR images of the patients and the CT images of the models. The results showed that the mean values of the errors in gap ranged from 1.19 to 2.22 mm, which was satisfactory for the surgeons. The feedback from both surgeons and patients demonstrated the usefulness and convenience of the models for efficient patient explanation understanding and pre-surgical planning by surgeons.     

Metastatic gastrinoma to the liver 20 years after primary resection

Gastrinoma is a rare endocrine tumor that is frequently associated with liver metastasis. The liver metastasis is usually seen simultaneously or soon after a primary operation. A 47-year-old woman who had had a total gastrectomy 20 years earlier developed liver metastasis. An interval of this length between surgery and metastasis is extremely rare. The total gastrectomy prevented the patient from developing the usual symptoms of hypergastrinemia that would have enabled early diagnosis of the metastasis. Laboratory examinations on admission revealed a high serum gastrin concentration (1500 pg/ml). Computed tomography showed an irregularly enhanced mass lesion with an uneven, low-density central area in the right anterior inferior segment of the liver. An extended right hepatectomy was performed. Intraoperative ultrasonography showed no abnormalities in the remnant pancreas. Examination of the cut surface of the specimen revealed a yellow, firm, elastic tumor, 55 mm in diameter. The interior of the tumor appeared necrotic. Histopathologically, the tumor was composed of cells with hyperchromatic, dysplastic nuclei arranged in a trabecular pattern with nest formation. Gastrin staining was positive. A histologic diagnosis of metastatic gastrinoma was made. The patient's gastrin concentration returned to normal and she was well at 2-year follow-up. Received: August 19, 1999 / Accepted: January 28, 2000     

Eigenspace Template Matching for Detection of Lacunar Infarcts on MR Images

Detection of lacunar infarcts is important because their presence indicates an increased risk of severe cerebral infarction. However, accurate identification is often hindered by the difficulty in distinguishing between lacunar infarcts and enlarged Virchow-Robin spaces. Therefore, we developed a computer-aided detection (CAD) scheme for the detection of lacunar infarcts. Although our previous CAD method indicated a sensitivity of 96.8 % with 0.71 false positives (FPs) per slice, further reduction of FPs remained an issue for the clinical application. Thus, the purpose of this study is to improve our CAD scheme by using template matching in the eigenspace. Conventional template matching is useful for the reduction of FPs, but it has the following two pitfalls: (1) It needs to maintain a large number of templates to improve the detection performance, and (2) calculation of the cross-correlation coefficient with these templates is time consuming. To solve these problems, we used template matching in the lower dimension space made by a principal component analysis. Our database comprised 1,143 T₁- and T₂-weighted images obtained from 132 patients. The proposed method was evaluated by using twofold cross-validation. By using this method, 34.1 % of FPs was eliminated compared with our previous method. The final performance indicated that the sensitivity of the detection of lacunar infarcts was 96.8 % with 0.47 FPs per slice. Therefore, the modified CAD scheme could improve FP rate without a significant reduction in the true positive rate.