Search

We investigated the pathogenic relationship between cerebral microbleeds and lacunar strokes. Two cases of lacunar strokes in the region of the basal ganglia, a 72-year-old man and a 67-year-old man, were studied; both cases showed cerebral microbleeds in the stroke areas. The cerebral microbleeds were surrounded by oedema, and the oedema faded out over time, suggesting the cerebral microbleeds had developed acutely. The cerebral microbleeds were located at the ventrolateral edge of the lacunar infarctions, and the locations appeared to be at or near the sites of occlusion of the lenticulostriatal branches. Although a cerebral microbleed and a lacunar infarction may be two unrelated events on juxtapositioned vessels, or a cerebral microbleed may be haemorrhagic conversion of an infarction, a cerebral microbleed could cause an occlusion of the arterial branch, leading to lacunar infarction of its supplying territories.

The cumulative intracranial tumor volume (CITV) has recently been suggested to be a more relevant predictive factor for patients with brain metastases (BM) treated with stereotactic radiosurgery (SRS). We aimed to investigate the feasibility of upfront SRS for patients with BM having a high CITV, i.e., exceeding 7 ml. Two hundred thirty-three consecutive patients with BM having a CITV > 7 ml who underwent SRS as first-line treatment from 2011 to 2019 were retrospectively identified. The overall survival (OS) and intracranial disease control rates were analyzed. Multivariate proportional hazards models were used to identify prognostic factors associated with treatment outcome. Toxicity and salvage therapy were also investigated. The median OS was 8.7 months (95% confidence interval: 7.1–10.4), and 6-month and 1-year OS rates were 60 and 40%, respectively. Systemic anticancer therapy (hazard ratio (HR): 0.45, p 7 ml.

OBJECTIVETwo-session Gamma Knife surgery (GKS) has recently been demonstrated to be an effective and less-invasive alternative for large brain metastases not treatable by microsurgical resection. This raises the clinical question of whether the 2-session GKS strategy further improves treatment outcomes for patients with symptomatic midsize brain metastases (2–10 cm3) as compared to single-session GKS. The present study aimed to compare the local therapeutic effects and toxicities of single-session and 2-session GKS for treating these lesions.METHODSPatients with focal neurological deficits attributable to midsize brain metastases who underwent upfront GKS during the period from 2010 to 2018 were retrospectively identified from an institutional database. Patients for whom both post-GKS imaging studies and neurological evaluations from outpatient visits were available were eligible. Using propensity score–matching (PSM) analysis, unique matched pairs which had a similar likelihood of receiving 2-session GKS were generated. The main outcome measure was a composite of imaging and/or neurological worsening of the lesion of interest. Functional improvement and overall survival (OS) were also compared between the 2 treatment arms.RESULTSIn total, 219 cancer patients with 252 symptomatic midsize brain metastases were eligible. Of these 252 tumors, 176 and 76 were treated with single- and 2-session GKS, respectively. After PSM, 68 pairs of tumors were obtained. The Gray test showed that 2-session GKS achieved a longer local progression–free interval than single-session GKS (1-year local control rate: 84% vs 53%; HR 0.31, 95% CI 0.16–0.63, p = 0.001). Two-session GKS was also associated with greater functional improvement in KPS scores (mean 18.3 ± 14.6 vs 12.8 ± 14.1, p = 0.040). The median OS did not differ significantly between single- and 2-session GKS (15.6 vs 24.7 months; HR 0.69, 95% CI 0.44–1.10, p = 0.11).CONCLUSIONSTwo-session GKS achieved more durable local tumor control and greater functional improvement than single-session GKS for patients with symptomatic midsize brain metastases, although there was no OS advantage.

Intravascular lymphoma (IVL) is a rare and clinically devastating subtype of extranodal diffuse large B-cell lymphoma with a distinct presentation. Diagnostic difficulty derives from marked variability in clinical presentations and nonspecific laboratory and radiological findings, especially when central nervous system (CNS) symptoms are the only manifestation. Establishing the diagnosis premortem thus remains a major challenge. We describe a 70-year-old male with CNS IVL. He presented with acute onset of neurocognitive impairments. Diffusion-weighted magnetic resonance imaging (MRI) showed multiple high-intensity areas suggesting occlusive cerebrovascular disease due to emboli, but extensive investigations detected no embolic sources. Intracranial neoplasm was included in a differential diagnosis based on elevated serum lactate dehydrogenase and interleukin 2 receptor levels. Gadolinium-enhanced MRI or 18-fluorodeoxyglucose positron emission tomography (PET) failed to demonstrate specific findings leading to a definite diagnosis, while 11C-methionine PET (MET-PET) distinctively demonstrated an area of focally increased MET uptake in the frontal cortex, suggesting the extent of tumor infiltration. Stereotactic biopsy was conducted under MET-PET imaging guidance and immunohistological examinations confirmed the proliferation and aggregation of CD20-positive lymphoma cells within the lumina of small blood vessels. The findings of the present case first suggest that MET-PET may provide important information on the diagnosis of CNS IVL and on the selection of the optimal site for brain biopsy. Further investigation is necessary to clarify whether positive findings on MET-PET are truly specific and pathognomonic for CNS IVL.

Background: Vascular access (VA) guidelines recommend the native arteriovenous fistula (AVF) as VA of first choice for chronic hemodialysis patients. AVF management is important in hemodialysis patient care. AVF survival is associated with various physical factors, but the effects of dialysis treatment factors upon AVF survival are still not clear. Methods: Study patients were treated at 498 dialysis facilities participating in the Dialysis Outcomes and Practice Patterns Study (DOPPS) 2 or 3 (2002-2007). Analyses included 1,183 incident hemodialysis patients (on dialysis ≤7 days and using an AVF at study entry) and 949 prevalent patients (on dialysis >7 days at DOPPS entry and using a new AVF created during study observation). AVF survival was modeled from the study entry date for incident patients and date of first AVF use for prevalent patients. Predictors of primary and final AVF survival were compared across Japan, North America and Europe/Australia/New Zealand (EUR/ANZ) with adjustments for patient characteristics. Results: No meaningful relationship was seen between AVF survival and various physician and staff practices. However, patients with prior catheter use displayed higher rates of primary and final AVF failure. Final AVF failure rates were higher in facilities with higher median blood flow rates (BFR). They were also greater in North America and EUR/ANZ than in Japan, but this difference was substantially attenuated after accounting for regional differences in facility median BFR. Conclusion: AVF longevity differed according to the DOPPS region, and was related to prior patient catheter use and facility BFR practice. Further longitudinal studies may help demonstrate meaningful associations between VA-handling skill and patency.

The optimal chemotherapeutic regimen for cancer of unknown primary (CUP) remains uncertain. We encountered 3 cases with CUP who presented with thoracic lymph node metastasis. Detailed physical examination and diagnostic tests, including laboratory investigations, bronchoscopy, upper and lower gastrointestinal studies, computed tomography of the head, neck, abdomen and pelvis and 18F-fluorodeoxyglucose positron emission tomography, failed to identify the primary site in these cases. The patients were treated with the cisplatin plus docetaxel chemotherapy regimen. Concomitant thoracic radiotherapy was conducted in one patient and surgical resection in another. All patients showed good response to the chemotherapy and achieved long-term disease-free survival.

In this paper, the performance of mid-link spectral inversion (MLSI)-based transmission is quantitatively compared to the performance for 'conventional' dispersion compensating fiber (DCF)-based transmission. Bit error rates (BER) are measured at optimized residual dispersion for all sixteen channels after 800km transmission in standard single mode fiber (SSMF). We show that for the MLSI-based configuration up to a decade of improvement in BER is obtained compared to the DCF based system. MLSI has the potential of lowering the cost of long haul transmission systems since instead of having multiple DCF modules per span only one spectral inverter is required for the whole transmission line. For spectral inversion, a polarization independent magnesium-oxide-doped periodically-poled lithium-niobate (MgO:PPLN) based subsystem was used.

To investigate the value of magnetic resonance imaging (MRI) in determining the parent nerves of neurogenic tumors in the thoracic inlet, analysis of MR images was performed in nine patients with surgically resected neurogenic tumors in the thoracic inlet (two neurofibromas and one schwannoma of the vagus nerve, three schwannomas of the brachial plexus, and two schwannomas and one ganglioneuroma of the sympathetic nerves). These MR images were compared with surgical and pathologic findings. The multidirectional capability and excellent tissue contrast of MRI facilitated recognition of the location, shape, and extent of the tumors. MRI, which permitted an easy understanding of the spatial relation between the tumors and the subclavian vessels, scalenus muscles, and brachial plexus, was useful in determining the nerves of origin. Two neurofibromas, four of six schwannomas, and one ganglioneuroma were recognized to extend along the axes of the parent nerves on MR images. MRI is useful in determining the parent nerve of neurogenic tumors in the thoracic inlet and is helpful in planning surgical treatment of these tumors.

The aim of this study was to estimate radiation exposure and evaluate the risks and benefits of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) in cancer screening. A nationwide survey of FDG-PET cancer screening was conducted in 2006, and the results were analyzed with a common index, “extension/shortening of the average life expectancy.” The average estimated effective dose was 4.4 mSv (male 4.7 mSv; female 4.0 mSv) for dedicated PET and 13.5 mSv (male 14.2 mSv; female 12.8 mSv) for PET/computed tomography (CT). The risk–benefit break-even age from the viewpoint of radiation exposure was in the 40s for men and 30s for women for dedicated PET and in the 50s for men and 50s (variable injection dose) or 60s (constant injection dose) for women for PET/CT. FDG-PET cancer screening is beneficial for examinees above the break-even ages. The risks and benefits should be explained to examinees because of the larger radiation used in cancer FDG-PET screening compared with other X-ray tests.

The most distinctive feature of FDG-PET cancer screening program is the ability to find various kinds of malignant neoplasms in a single test. The aim of this survey is to clarify the range and frequency of various malignant neoplasms detected by FDG-PET cancer screening performed in Japan."FDG-PET cancer screening" was defined as FDG-PET or positron emission tomography and computed tomography (PET/CT) scan with or without other tests performed for cancer screening of healthy subjects. This survey was based on a questionnaire regarding FDG-PET cancer screening. We analyzed the situation of 9 less frequently found malignant neoplasms including malignant lymphoma, malignancy of head and neck, esophagus, hepatobiliary and gallbladder, pancreas, kidney, cervical and uterine, ovary, and bladder.The detailed information of subjects with the suspected 9 kinds of malignant neoplasms mentioned above in the FDG-PET cancer screening program was studied in a total of 1,219 cases from 212 facilities. A statistical significance between PET/CT and PET was found in relative sensitivity and PPV for renal cell cancer. Malignant lymphoma was frequently of indolent type, suspected head and neck cancers had many false-positive results, and pancreatic cancer detected in this program was often in the advanced stage even in asymptomatic subjects. The recommendation of combined screening modality to PET or PET/CT was as follows: gastric endoscopy for assessing early esophageal cancer; abdominal ultrasound for screening hepatobiliary and gallbladder cancer; pelvic magnetic resonance imaging for assessing gynecological and pelvic cancers; and the CA125 blood test for screening ovarian cancer. Delayed image was helpful depending on the type of suspected malignant neoplasm.We analyzed various types of malignant neoplasms detected by the FDG-PET cancer screening program and presented recommended combination of examinations to cover FDG-PET and PET/CT.