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1.
Med Phys ; 39(7): 4073-8, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22830740

ABSTRACT

PURPOSE: To investigate the feasibility of implementing a novel approach for patient-specific QA of TomoDirect(TM) whole breast treatment. METHODS: The most currently used TomoTherapy DQA method, consisting in the verification of the 2D dose distribution in a coronal or sagittal plane of the Cheese Phantom by means of gafchromic films, was compared with an alternative approach based on the use of two commercially available diode arrays, MapCHECK2(TM) and ArcCHECK(TM). The TomoDirect(TM) plans of twenty patients with a primary unilateral breast cancer were applied to a CT scan of the Cheese Phantom and a MVCT dataset of the diode arrays. Then measurements of 2D dose distribution were performed and compared with the calculated ones using the gamma analysis method with different sets of DTA and DD criteria (3%-3 mm, 3%-2 mm). The sensitivity of the diode arrays to detect delivery and setup errors was also investigated. RESULTS: The measured dose distributions showed excellent agreement with the TPS calculations for each detector, with averaged fractions of passed Γ values greater than 95%. The percentage of points satisfying the constraint Γ < 1 was significantly higher for MapCHECK2(TM) than for ArcCHECK(TM) and gafchromic films using both the 3%-3 mm and 3%-2 mm gamma criteria. Both the diode arrays show a good sensitivity to delivery and setup errors using a 3%-2 mm gamma criteria. CONCLUSIONS: MapCHECK2™ and ArcCHECK(TM) may fulfill the demands of an adequate system for TomoDirect(TM) patient-specific QA.


Subject(s)
Algorithms , Breast Neoplasms/radiotherapy , Quality Assurance, Health Care/methods , Radiometry/methods , Radiometry/standards , Radiotherapy Planning, Computer-Assisted/methods , Radiotherapy Planning, Computer-Assisted/standards , Female , Humans , Italy , Radiotherapy Dosage
2.
Br J Radiol ; 85(1015): e330-8, 2012 Jul.
Article in English | MEDLINE | ID: mdl-21937611

ABSTRACT

OBJECTIVE: Medical diagnostic procedures can be considered the main man-made source of ionising radiation exposure for the population. Conventional radiography still represents the largest contribution to examination frequency. The present work evaluates procedure frequency and effective dose from the majority of conventional radiology examinations performed at the Radiological Department of Aosta Hospital from 2002 to 2009. METHOD: Effective dose to the patient was evaluated by means of the software PCXMC. Data provided by the radiological information system allowed us to obtain collective effective and per caput dose. RESULTS: The biggest contributors to per caput effective dose from conventional radiology are vertebral column, abdomen, chest, pelvis and (limited to females) breast. Vertebral column, pelvis and breast procedures show a significant dose increment in the period of the study. The mean effective dose per inhabitant from conventional radiology increased from 0.131 mSv in 2002 to 0.156 mSv in 2009. Combining these figures with those from our study of effective dose from CT (0.55 mSv in 2002 to 1.03 mSv in 2009), the total mean effective dose per inhabitant increased from 0.68 mSv to 1.19 mSv. The contribution of CT increased from 81% to 87% of the total. In contrast, conventional radiology accounts for 85% of the total number of procedures, but only 13% of the effective dose. CONCLUSION: The study has demonstrated that conventional radiography still represents the biggest contributor to examination frequency in Aosta Valley in 2009. However, the frequency of the main procedures did not change significantly between 2002 and 2009.


Subject(s)
Diagnostic Imaging/statistics & numerical data , Radiation Dosage , Radiation, Ionizing , Radiometry/methods , Adolescent , Adult , Aged , Child , Cohort Studies , Databases, Factual , Diagnostic Imaging/trends , Dose-Response Relationship, Radiation , Environmental Exposure , Female , Humans , Incidence , Italy , Male , Middle Aged , Radiography/statistics & numerical data , Radiography/trends , Radiology Department, Hospital , Reference Values , Retrospective Studies , Risk Assessment , Young Adult
3.
Br J Radiol ; 83(996): 1042-51, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21088089

ABSTRACT

Recent and continuous advances in CT, such as the development of multislice CT, have promoted a rapid increase in its clinical application. Today, CT accounts for approximately 10% of the total number of medical radiographic procedures worldwide. However, the growing performance of the new CT generations have increased not only the diagnostic opportunities, but also the radiation dose to the patient. The relative contribution to the collective radiation dose is now estimated to be approximately 50%. Several papers have been published concerning the intensive use of CT and its contribution to the collective dose. However, most of the literature concerns the years 1997-2003 and the dosimetric evaluations are generally limited to the main standard protocols (chest, head and abdomen), deriving the effective dose by the simple application of the diagnostic reference levels. Only specific dosimetric analyses of single and innovative procedures have been published recently. Moreover, few data comes from Italian radiology departments. This paper aims to bridge these gaps. Firstly, it characterises in terms of measured CT dose index (CTDI) two last-generation scanners of the Radiological Department of Aosta Hospital. Secondly, it evaluates the effective dose from most of the CT examinations performed from 2001 to 2008 to compare protocols and technologies in line with the suggestions of the 2007 Recommendations of the International Commission on Radiological Protection, Publication 103. Finally, it estimates the collective dose to the population.


Subject(s)
Environmental Exposure/adverse effects , Radiation, Ionizing , Tomography Scanners, X-Ray Computed/standards , Tomography, X-Ray Computed/standards , Female , Humans , Italy/epidemiology , Male , Medical Audit , Radiation Dosage , Radiometry , Reference Values , Tomography, X-Ray Computed/instrumentation , Tomography, X-Ray Computed/methods
4.
Pacing Clin Electrophysiol ; 23(9): 1448-50, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11025908

ABSTRACT

The case of a 83-year-old patient undergoing DDD pacemaker implantation for sick sinus syndrome with postimplant detection of advanced interatrial conduction block is described. At nominal AV interval programming values (175 ms), absence of P wave following an atrial spike was observed, and the presence of an interatrial conduction disturbance was demonstrated by a Doppler transmitral flow pattern analysis and transesophageal ECG recording. AV interval lengthening up to 300 ms resulted in proper timing of atrial and ventricular contractions. Awaiting for conclusive data about biatrial pacing, interatrial conduction blocks can be managed in some cases by proper programming of conventional DDD systems.


Subject(s)
Atrioventricular Node/physiopathology , Heart Block/therapy , Pacemaker, Artificial , Aged , Aged, 80 and over , Electrocardiography , Heart Block/diagnosis , Heart Block/physiopathology , Humans , Male
5.
Ital Heart J Suppl ; 1(7): 939-42, 2000 Jul.
Article in Italian | MEDLINE | ID: mdl-10935741

ABSTRACT

We report the case of a VDD single-lead pacemaker implantation through a persistent left superior vena cava in a 48-year-old male patient with recurrent episodes of syncope due to paroxysmal atrioventricular block. VDD lead insertion through the anomalous venous structure led to positioning of the floating sensing dipole into the coronary sinus, in a very large and stable sensed atrial signal due to the close anatomic relationship between the coronary sinus and the left atrium. Shortness of the sensed atrioventricular interval allowed VDD stimulation to occur only in the case of paroxysmal atrioventricular block.


Subject(s)
Cardiac Pacing, Artificial , Heart Block/therapy , Vena Cava, Superior , Catheterization , Humans , Male , Middle Aged , Vena Cava, Superior/abnormalities
6.
Clin Ter ; 141(12): 457-64, 1992 Dec.
Article in Italian | MEDLINE | ID: mdl-1493667

ABSTRACT

A group of 196 outpatients among whom 112 non-insulin-dependent diabetics were divided into 4 subgroups according to whether they had vascular disorders or not. For statistical evaluation by means of correlation coefficient and chi-square test both risk factors (smoking, family history, arterial hypertension, BMI) and laboratory values (total and HDL cholesterol, triglycerides, fibrinogen, HbA1c, factor VIII, PF4, BTG) were taken into account. Our findings confirm the relevance of risk factors and the need for diabetic patients to be metabolically well balanced; PF4, BTG, and factor VII were normal in all patients which suggests that these are not suitable, as far as the present study is concerned, to be considered markers of vascular disorders. An interesting correlation was found between these factors and serum triglycerides, especially in the subgroup of diabetics with vascular disorders. An interesting finding was the increase of fibrinogen in subjects with vascular disorders especially in non-diabetics.


Subject(s)
Arteriosclerosis/epidemiology , Adult , Arteriosclerosis/diagnosis , Arteriosclerosis/etiology , Chi-Square Distribution , Chronic Disease , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/epidemiology , Diabetic Angiopathies/diagnosis , Diabetic Angiopathies/epidemiology , Diabetic Angiopathies/etiology , Female , Humans , Italy/epidemiology , Male , Middle Aged , Risk Factors
7.
Pacing Clin Electrophysiol ; 15(11 Pt 2): 1901-2, 1992 Nov.
Article in English | MEDLINE | ID: mdl-1279568

ABSTRACT

The implantation of a VDD system is comparable to that of a VVI system, but its management is associated with typical complications of dual chamber pacing. In 35 patients with symptomatic AV block and normal sinus node function, two different VDD pacing systems were implanted. Most of the complications described and their mode of resolution were common to VDD and DDD pacing; however, the VDD system eliminated the need for two separate leads. We, therefore, favor single lead VDD pacing in the treatment of complete AV block with normal sinus node function.


Subject(s)
Cardiac Pacing, Artificial/methods , Heart Block/therapy , Pacemaker, Artificial/adverse effects , Aged , Cardiac Pacing, Artificial/adverse effects , Electrodes, Implanted , Equipment Design , Equipment Failure , Female , Humans , Male , Tachycardia/etiology
8.
G Ital Cardiol ; 21(12): 1325-9, 1991 Dec.
Article in Italian | MEDLINE | ID: mdl-1818004

ABSTRACT

We describe a case of non-obstructive apical hypertrophic cardiomyopathy in an 86-year-old Caucasian patient, whose electrocardiographic and echocardiographic patterns coincided with those originally described by the Japanese Authors. We documented the evolution of the patient's electrocardiographic alterations over a 16-year period, in absence of symptoms, except for one syncopal episode, which occurred 13 years ago.


Subject(s)
Cardiomyopathy, Hypertrophic/diagnosis , Electrocardiography , Age Factors , Aged , Aged, 80 and over , Cardiomyopathy, Hypertrophic/complications , Female , Humans , Syncope/etiology , Time Factors
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