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3.
PURPOSE: To determine whether a little dose to a large normal lung volume or a high dose to a small lung volume is more critical for induction of clinical pneumonitis. The second question is if dose-volume histogram (DVH) parameters are more reliable, if the lungs are analyzed as separate organs or as a whole organ. PATIENTS AND METHODS: We analyzed the clinical and DVH data from 49 patients treated for a thoracic malignancy using 3-D conformal treatment plans. 18 patients had developed a clinical pneumonitis (CTC II or III). The majority of patients (n = 48) received radiochemotherapy for non-small-cell lung cancer (NSCLC) with a combination of paclitaxel and carboplatin. Patients were generally treated 5 fx/week, single dose 2 Gy, using a two-series approach (shrinking field) up to a total dose of 60-70 Gy. For every individual patient, the overall dose distribution was recalculated in the Helax-TMS by means of adding dose plans according to the total dose applied in each series. The lungs were defined both as separate organs and as a whole organ. Low-dose volume (< or = 10 Gy, Vlow), moderate-dose volume (> 10-40 Gy, Vmod) and high-dose volume (> 40 Gy, Vhigh), as well as V10-V40 and mean lung dose (MLD) were defined from the cumulative DVH. Dose-effect relationships were fitted with a logistic regression model. RESULTS: Manifestation of clinical pneumonitis was within 3 months from termination of irradiation in all cases. For the ipsilateral lung, the incidence of pneumonitis was closely correlated to Vhigh. The pneumonitis rate increased from 13% up to 60%. By contrast, with increasing Vlow the pneumonitis rate dropped to < 10%. A similar but less pronounced effect was seen for the total lung. The lung volumes Vlow, Vmod and Vhigh of the ipsilateral, contralateral and whole lung were significantly correlated to the corresponding MLD. The incidence of pneumonitis increased with increasing MLD for the ipsilateral lung with a D50 of 32 Gy and a gamma 50 of 0.98. For the whole lung, the observed increase was less steep. MLD showed a close correlation to NTCP calculated by the Kutcher model. However, NTCP calculation overestimated the pneumonitis risk for the ipsilateral lung and underestimated the risk for the whole lung due to the steeper gradient. The logistic regression curve for the DVH parameters V10-V40 showed an increase of steepness toward higher doses. From the logistic regression curves, a DVH template indicating critical borders of V10-V40 was generated for the ipsilateral as well as for the total lung. CONCLUSION: Our data indicate that it is reasonable to disperse the dose outside the target volume over large areas in order to reduce the volumes of lung receiving > 40 Gy. Reducing the high-dose volume reduces the pneumonitis rate more than a corresponding reduction in the low-dose regions of the DVH. Landmarks for DVH optimization as defined in this analysis may serve as a basis for DVH contrains in IMRT planning. Separate organ analysis produced more reliable results and should be preferred to whole-organ analysis, if techniques mainly involving one side of the lung are applied. Further validation of these constraints is necessary prior to general recommendation. 相似文献
4.
A cannabimimetic indole has been identified as a new adulterant in a herbal product being sold illegally in Japan for its
expected narcotic effect. Liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry analyses indicated
that the product contained two major compounds. One was identified as a cannabinoid analog (1 RS,3 SR)-3-[4-(1,1-dimethyloctyl)-2-hydroxyphenyl]cyclohexan-1-ol ( 1) by direct comparison with the authentic compound, which we reported previously. The other compound ( 2) showed a molecular weight of 341 daltons, and accurate mass spectral measurements showed its elemental composition to be
C 24H 23NO. Both mass and nuclear magnetic resonance spectrometric data revealed that 2 was 1-pentyl-3-(1-naphthoyl)indole [or naphthalen-1-yl-(1-pentylindol-3-yl)methanone] being identical to JWH-018, which was
synthesized by Wiley and coworkers in 1998. This compound was reported as a potent cannabinoid receptor agonist possessing
a pharmacological cannabimimetic activity. 相似文献
5.
Hemodynamic events leading to spontaneous postexertional vasovagal syncope are not completely understood because of the lack of beat-to-beat data. We report a case study of a young athlete who undergoes a syncopal episode during the recovery period following a maximal cycle-ergometer test. The episode was monitored by an impedance cardiograph which can gather noninvasively beat-to-beat the flow of heart rate (HR), stroke volume (SV), cardiac output (CO), diastolic filling rate (SV/DT), and myocardial contractility index (PEP/LVET). The most important findings of this report are the dramatic reduction of SV/DT preceding the syncope, the increment of SV together with the reduction of HR preceding and following the syncope, the prompt recovery of CO values after the syncopal episode despite the bradycardia, and the reduction of PEP/LVET after the syncope. This report confirms the importance of active recovery immediately after strenuous exercise and supports the hypothesis that the reduction of SV/DT in the presence of an inotropic stimulation can trigger the vasovagal reaction. 相似文献
6.
The authors describe a case in which a 21-year-old male committed suicide using a rifle equipped with a muzzle brake, placed in contact with his head. A muzzle brake for firearms is a device positioned at the mouth of a weapon, which dissipates the gases, that are generated subsequent to the gun being discharged. Generally, when a gun is pressed against an anatomical region, where the skin lies on the bone surface without interposition of other soft parts, the entrance wound consists of many lacerated branches, originating from a central lack of tissue. In this case report, the use of a rifle with a muzzle brake generated an unexpected wound, circular in shape, with a diameter of 0.8 cm. This lesion was surrounded by a bruised area, circular in shape, and an abrasion collar of the height of 0.5 cm. In addition, a muzzle imprint mark consisting of intradermal bruises, composed of a narrow red line concentrically encircling the entrance hole, was found. In order to analyze in detail if this particular entrance wound could be associated with a weapon equipped with the muzzle brake, ballistic tests – with weapons compatible with that used by the victim – were performed. 相似文献
9.
The authors present a case which brings out a unique modality of child homicide by placing the baby in a washing machine and turning it on. The murder was perpetrated by the baby’s mother, who suffered from a serious depressive disorder. A postmortem RX and then a forensic autopsy were performed, followed by histologic examinations and toxicology. On the basis of the results of the autopsy, as well as the histology and the negative toxicological data, the cause of death was identified as acute asphyxia. This diagnosis was rendered in light of the absence of other causes of death, as well as the presence of typical signs of asphyxia, such as epicardial and pleural petechiae and, above all, the microscopic examinations, which pointed out a massive acute pulmonary emphysema. Regarding the cause of the asphyxia, at least two mechanisms can be identified: drowning and smothering. In addition, the histology of the brain revealed some findings that can be regarded as a consequence of the barotrauma due to the centrifugal force applied by the rotating drum of the washing machine. Another remarkable aspect is that we are dealing with a mentally-ill assailant. In fact, the baby’s mother, after a psychiatric examination, was confirmed to be suffering from a mental illness—a severe depressive disorder—and so she was adjudicated not-guilty-by-reason-of-insanity. This case warrants attention because of its uniqueness and complexity and, above all, its usefulness in the understanding of the pathophysiology of this particular manner of death. 相似文献
10.
The hydatid cyst of the liver is the most common location of hydatid disease. Complications in this form are dominated by superinfection of the cyst and rupture into the bile ducts or the peritoneal cavity. We report the case of a 54-year-old female patient with a hydatid cyst of the liver complicated by a rupture in the gallbladder revealed by urinary symptoms. 相似文献
12.
Sacral tumors with fetiform features are rare and pose a diagnostic challenge to the ultrasonologist. Sacrococcygeal teratomas (SCT) and parasitic twins can have very similar sonographic features but have different implications to an affected pregnancy. While postnatal histopathology is ultimately necessary to distinguish between a SCT and a heteropagus twin, certain characteristics, such as the presence of a vertebral column and the pattern and rate of tumor growth, may be useful to guide counseling and management decisions. 相似文献
13.
The unusual case of a mandibular arteriovenous malformation in a patient with severe hemophilia A and hepatitis C is reported. Supplementary substitution of various coagulation factors allowed direct puncture and intralesional injection of a liquid adhesive, resulting in complete anatomic and clinical cure without peri- or postoperative bleeding. Replacement therapy providing normal levels of relevant coagulation factors enables endovascular treatment in a safe and effective manner in hemophiliac patients. 相似文献
14.
We describe an unusual pseudotumor of the upper thorax, axillary, and shoulder girdle region with presentation 4 years after
a surfing sports injury. We offer the coined term “Surfinoma” to describe a pseudotumor arising from a penetrating piece of
fiberglass surf board, which induced a foreign body reaction. 相似文献
17.
Efficacy of Venoruton--O-(hydroxyethyl) Rutoside--as a radioprotector has been tested on haematological profile of rats which were subjected to whole body radiation (500 rads). The results show radiation induced lesions in respect of total (TLC) and differential leukocyte counts (DLC)/and haemoglobin are significantly lessened when Venoruton was administered prior to radiation exposure. 相似文献
20.
The role of a team physician is an integral part of establishing a new practice. Regardless of the type of practice one enters, the team physician role provides an opportunity to establish an early referral base to build the foundation of a successful practice. Although this comes with great responsibility and significant time commitments, the joy of developing your practice doing what you enjoy most, sports medicine, makes these drawbacks less perceptible. Using all your potential resources and keeping your eye on the ball will simplify reaching the goal of having a happy, healthy, and rewarding career. 相似文献
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