Shoma Berkemeyer

Comparison of a Balloon Guide Catheter and a Non–Balloon Guide Catheter for Mechanical Thrombectomy

Purpose To evaluate the effectiveness of mechanical thrombectomy with the use of a stent retriever in acute ischemic stroke, performed by using a balloon guide catheter or non-balloon guide catheter. Materials and Methods In accordance with the institutional review board approval obtained at the two participating institutions, retrospective analysis was performed in 183 consecutive patients treated between 2013 and 2014 for occlusions in the middle cerebral artery or carotid terminus by using a stent retriever with a balloon guide catheter (n = 102) at one center and a non-balloon guide catheter (n = 81) at the other center. Data on procedure duration, number of passes, angiographic findings, type of stent retriever used, and expertise of the operators were collected. Successful recanalization was defined as grade 3 or 2b modified Treatment in Cerebral Ischemia recanalization accomplished in up to three passes. Univariate and multivariate subgroup analyses were conducted to control for the confounding variables of prior thrombolysis, location of occlusion, and operator expertise. Results Successful recanalization with the balloon guide catheter was achieved in 89.2% of thrombectomies (91 of 102) versus 67.9% (55 of 81) achieved with the non-balloon guide catheter (P = .0004). The one-pass thrombectomy rate with the balloon guide catheter was significantly higher than for that with the non-balloon guide catheter (63.7% [65 of 102] vs 35.8% [29 of 81], respectively; P = .001). The procedure duration was significantly shorter by using the balloon guide catheter than the non-balloon guide catheter (median, 20.5 minutes vs 41.0 minutes, respectively; P < .0001). Conclusion The effectiveness of mechanical thrombectomy with stent retrievers in acute ischemic stroke in the anterior circulation in terms of angiographic results and procedure duration was improved when performed in combination with the balloon guide catheter. (©) RSNA, 2016.

Digital Mammography Screening: Association between Detection Rate and Nuclear Grade of Ductal Carcinoma in Situ

PURPOSE To determine the relationship between overall detection rates of ductal carcinoma in situ (DCIS) and the specific detection rates of low-, intermediate-, and high-grade DCIS at the start of a digital mammography screening program. MATERIALS AND METHODS The study was approved by the local ethics board and did not require informed consent. Data were included of the first round of digital mammography examinations, performed in 17 screening units in women aged 50-69 years from 2005 to 2008. Grading was provided by the cancer registry for 1018 DCIS cases. The association between the overall cancer detection rate (cases per 100 women screened) and the separate cancer detection rate for invasive cancers and for DCIS was assessed. Likewise, the total DCIS cancer detection rate was separated into rates for low, intermediate, and high grades. Spearman rank correlations were used for analysis. RESULTS The overall cancer detection rate correlated with both the cancer detection rate of invasive cancers and the cancer detection rate of DCIS (r = 0.96 and r = 0.88, respectively; P < .001 for both). The cancer detection rate of total DCIS with grading varied among screening units (range, 0.05-0.25), it was borderline not significantly correlated with the cancer detection rate of low-grade DCIS (range, 0.004-0.05; r = 0.49; P = .052), and it showed significant correlations with higher cancer detection rate of intermediate-grade DCIS (range, 0.02-0.12; r = 0.89; P < .001) and of high-grade DCIS (range, 0.03-0.11; r = 0.88; P < .001). CONCLUSION This study demonstrates that high overall cancer detection rates in digital mammography screening are related to high detection rates of invasive cancers, as well as DCIS. Increases in the detection rates of DCIS were not driven by disproportionate increments of the slowly progressive low-grade subtype but rather by increased rates of intermediate- and high-grade subtypes that carry a higher risk of transition to invasive cancers.

Digital Mammography Screening with Photon-counting Technique: Can a High Diagnostic Performance Be Realized at Low Mean Glandular Dose?

PURPOSE To assess screening performance of a direct radiography (DR) photon-counting system versus statewide screening units with different digital technologies. MATERIALS AND METHODS The local ethics board approved retrospective study of prospectively acquired data from the North Rhine-Westphalian mammography screening program (2009-2010). Informed consent was waived. Examinations in 13 312 women with a DR photon-counting system and statewide digital screening examinations in 993 822 women were included (37 computed radiography mammography systems and 55 DR systems). Diagnostic performance was assessed with cancer detection rate, recall rate, and proportion of small invasive cancers and ductal carcinoma in situ (DCIS). Mean glandular dose was calculated for DR photon counting and for a conventional DR subgroup. Differences were tested with χ(2) and t tests (P < .05). RESULTS The cancer detection rate for subsequent screenings was higher for DR photon counting than statewide rates (0.76% [67 of 8842] vs 0.59% [3108 of 527 194], P = .05) at a higher recall rate (5.4% [475 of 8842] vs 3.3% [17 656 of 527 194], P = .001). Detection of invasive cancers up to 10 mm for DR photon counting was high for initial (40% [14 of 35]) and subsequent (42% [19 of 45]) screenings but not significantly different from statewide rates (initial, 31.6% [942 of 2979], P = .50; subsequent, 32.5% [765 of 2353], P = .25). The DCIS subsequent screening rate was higher for DR photon counting than statewide screening (0.23% [20 of 8842] vs 0.12% [616 of 527 194], P = .01) and the conventional DR subgroup (0.23% [20 of 8842] vs 0.12% [65 of 52 813], P = .025). Mean glandular dose for DR photon counting was significantly lower than that for conventional DR (0.60 mGy ± 0.20 vs 1.67 mGy ± 0.47 [craniocaudal views], 0.64 mGy ± 0.23 vs 1.79 mGy ± 0.53 [mediolateral oblique views], both P = .0001). CONCLUSION Digital mammography screening with dose-efficient photon counting enables desirable detection rates of small invasive cancers and DCIS. Higher detection rates compared with statewide performance occurred with subsequent screening but had higher recall rates.

Acid-base balance and weight gain: are there crucial links via protein and organic acids in understanding obesity?

Obesity is associated with ever increasing social costs posing a general public health challenge. The most obvious reason for obesity, given healthy body functioning, is a positive calorie balance. This article delves into the lesser studied realm of the relationship of weight gain, in particular adipose tissue gain, with increased hydrogen ion concentration, taking protein and organic acids as important caveats in this discussion. The review opens the topic with the contradictory result of various studies reporting a positive relationship between chronic metabolic acidosis and weight loss. It goes to explain a process of weight gain, primarily adipose tissue gain, on acidogenic diets. Insufficient dietary protein could lead to muscle loss, and individual organic acids might indicate if there is any fatty acid oxidation or accumulation of hydrogen ion. The solution to the acid accumulation is discussed not in protein limitation but an increase in the consumption of vegetables and fruits. Finally, this review article based on studies published puts forward a physiological basis including a hypothesis to explain the possible link between hydrogen ion concentration and weight gain. This link could possibly explain the development of diseases and aging partially, and warrants research.

The straight line hypothesis elaborated: Case reference obesity, an argument for acidosis, oxidative stress, and disease conglomeration?

Studies report on the association between obesity and oxidative stress, with and without additional diseases. Macrophages in adipocytes, and hypoxia in adipose tissue have been suggested to explain how obesity can relate to oxidative stress. The straight line hypothesis using the lactic acid trap construct has been put forward to explain how proton imbalance can relate to obesity. Proton imbalance has been also reported to associate with the production of reactive oxygen species by inhibition of mitochondrial energy production. This review brings together existing literature and concepts to explain how obesity can relate to oxidative stress via protons, uniquely for itself or, as often observed, in conglomeration of additional diseases.

Bone T-Scores and Functional Status: A Cross-Sectional Study on German Elderly

Background We explore the association between bone T-scores, used in osteoporosis diagnosis, and functional status since we hypothesized that bone health can impact elderly functional status and indirectly independence. Methods In a cross-sectional study (2005–2006) on community dwelling elderly (> = 75 years) from Herne, Germany we measured bone T-scores with Dual-energy X-ray Absorptiometry, and functional status indexed by five geriatric tests: activities of daily living, instrumental activities of daily living, test of dementia, geriatric depression score and the timed-up-and-go test, and two pooled indexes: raw and standardized. Generalized linear regression was used to determine the relationship between T-scores and functional status. Results From 3243 addresses, only 632 (19%) completed a clinical visit, of which only 440 (male∶female, 243∶197) could be included in analysis. T-scores (−0.99, 95% confidence interval [CI], −1.1–0.9) predicted activities of daily living (95.3 CI, 94.5–96.2), instrumental activities of daily living (7.3 CI, 94.5–96.2), and timed-up-and-go test (10.7 CI, 10.0–11.3) (P< = 0.05). Pooled data showed that a unit improvement in T-score improved standardized pooled functional status (15 CI, 14.7–15.3) by 0.41 and the raw (99.4 CI, 97.8–101.0) by 2.27 units. These results were limited due to pooling of different scoring directions, selection bias, and a need to follow-up with evidence testing. Conclusions T-scores associated with lower functional status in community-dwelling elderly. Regular screening of osteoporosis as a preventive strategy might help maintain life quality with aging.

Digital Mammography Screening: Does Age Influence the Detection Rates of Low-, Intermediate-, and High-Grade Ductal Carcinoma in Situ?

PURPOSE To investigate the association between age at screening and detection rates for ductal carcinoma in situ (DCIS) separately for different nuclear grades after introduction of a population-based digital mammography screening program. MATERIALS AND METHODS The retrospective study was approved by the ethics board and did not require informed consent. In 733 905 women aged 50-69 years who participated in a screening program for the first time in 2005-2008 (baseline examinations were performed with digital mammography), DCIS detection rates were determined for 5-year age groups (detection rates per 1000 women screened) to distinguish high-, intermediate-, and low-grade DCIS. Multivariable logistic regression was used to compare detection rates between age groups by adjusting for screening units (P < .05). RESULTS There were 989 graded DCIS diagnoses among 733 905 women (detection rate, 1.35‰): 419 diagnoses of high-grade DCIS (detection rate, 0.57‰), 388 diagnoses of intermediate-grade DCIS (detection rate, 0.53‰), and 182 diagnoses of low-grade DCIS (detection rate, 0.25‰). Detection rate for types of DCIS combined increased significantly across age groups (50-54 years, detection rate of 1.15‰ [254 of 220 985 women]; 55-59 years, detection rate of 1.23‰ [218 of 177 782 women]; 60-64 years, detection rate of 1.34‰ [201 of 150 415 women]; and 65-69 years, detection rate of 1.71‰ [316 of 184 723 women]; P < .001). Of note, the detection rate for high-grade DCIS showed a significant increase with age (odds ratio, 1.18 per 5-year age group; P < .0001). The increase was lower for intermediate-grade DCIS (odds ratio, 1.11; P = .016) and not significant for low-grade DCIS (P = .10). CONCLUSION Total DCIS detection rates increase with age, mostly because of an increase in high- and intermediate-grade DCIS, which are precursor lesions that carry a higher risk for transition to more aggressive invasive breast cancer than low-grade DCIS.

Incidence and Mortality Trends in German Women with Breast Cancer Using Age, Period and Cohort 1999 to 2008

Longitudinal analysis investigates period (P), often as years. Additional scales of time are age (A) and birth cohort (C) Aim of our study was to use ecological APC analysis for women breast cancer incidence and mortality in Germany. Nation-wide new cases and deaths were obtained from Robert Koch Institute and female population from federal statistics, 1999–2008. Data was stratified into ten 5-years age-groups starting 20–24 years, ten birth cohorts starting 1939–43, and two calendar periods 1999–2003 and 2004–2008. Annual incidence and mortality were calculated: cases to 100,000 women per year. Data was analyzed using glm and apc packages of R. Breast cancer incidence and mortality increased with age. Secular rise in breast cancer incidence and decline in mortality was observed for period1999-2008. Breast cancer incidence and mortality declined with cohorts; cohorts 1950s showed highest incidence and mortality. Age-cohort best explained incidence and mortality followed by age-period-cohort with overall declining trends. Declining age-cohort mortality could be probable. Declining age-cohort incidence would require future biological explanations or rendered statistical artefact. Cohorts 1949–1958 could be unique in having highest incidence and mortality in recent time or future period associations could emerge relatively stronger to cohort to provide additional explanation of temporal change over cohorts.

Net acid excretion capacity is related to blood hydrogen ion and serum carbon dioxide.

Acid-base imbalance due to dietary food patterns has emerged as one of the hypotheses leading to modern-day diseases. This study examined if a new method to assess the renal ability to excrete an acid load, that is, the net acid excretion capacity (NAEC), constructed from net acid excretion (NAE) and urine pH, relates to blood hydrogen ion concentration ([H+]) and serum carbon dioxide concentration ([CO2]). In a second analysis, NAE to pH relationship was examined, and is de facto treated to be linear. This study used historical, cross-sectional data of 58 repeated measurements from 8 subjects for the primary measurements of NAEC, blood [H+], and serum [CO2]. Using fixed models, higher NAEC associated with lower [H+] and higher [CO2]. Using hierarchical models, the interindividual variations in [H+] and [CO2] explained the variations in NAEC. In the second analysis (n = 59), a quadratic NAE to pH relationship (NAE = -846.77 + 341.47 pH - 31.50 pH(2)) can be reported. Net acid excretion capacity, a noninvasive tool to assess the renal ability to excrete an acid load, has a physiologic base to it, in that it captures the inherent nonlinear relations of NAE to pH explaining endogenous [H+] retention/excretion. A higher vegetable and fruit consumption might relieve NAEC and allow excess [H+] loss via both renal and respiratory routes.

A complementary explanation on the relationship of obesity and oxidative stress via protons.

TO THE EDITOR: The article “Loss of Total and Visceral Adipose Tissue Mass Predicts Decreases in Oxidative Stress After Weight-loss Surgery” (1) goes a long way to demonstrate the nexus between obesity and development of diseases, such as, hypertension, insulin resistance, diabetes, etc., via the proposed association of total and visceral adipose tissue and oxidative stress. Because the study does not mention another proposed crucial link via the protons [H], this addendum of a letter. The “straight line hypothesis of diet, acidosis, and aging” has been recently put forward (3), wherein obesity could result due to a direct increase in calorie consumption of a Western diet lifestyle (2), but indirectly over a net increase in [H+], which could support “relative obesity,” i.e., a loss of lean mass at maintenance (or increase) in fat mass/body weight (3). Acidosis is known to inhibit mitochondrial energy production (4,5), whereby it has been proposed that the electrons could be free for production of reactive oxygen species (ROS) (3–5). The present study provides some support toward this proposition. Additionally, another study reports on the association of obesity and increase in macrophages (6); an explanation also provided by the researchers of the present study to support their results. A complementary explanation, as per the straight line hypothesis, could be via the stepping-down of β-oxidation (burning of adipose tissue) with a surplus in [H] in diet, a phenomenon, which has been reported on independently in literature (7,8). In effect, it would imply lower ketoacid production, and to that extent attributable, a deposition of fat mass. The absolute increase in fat mass could associate with an increase in macrophages with a concomitant [H+] induced inhibition of mitochondrial energy production in favor of ROS.