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The British Journal of Radiology Jun 2017To evaluate the impact of a low-dose (LD) and an ultra-LD (ULD) contrast protocol for coronary CT angiography on qualitative and quantitative image parameters in a... (Comparative Study)
Comparative Study
A low-dose and an ultra-low-dose contrast agent protocol for coronary CT angiography in a clinical setting: quantitative and qualitative comparison to a standard dose protocol.
OBJECTIVE
To evaluate the impact of a low-dose (LD) and an ultra-LD (ULD) contrast protocol for coronary CT angiography on qualitative and quantitative image parameters in a clinical setting.
METHODS
We scanned 120 consecutive patients with a 256-slice CT scanner applying a LD (60 patients, 35-55 ml) or ULD (60 patients, 25-45 ml) contrast protocol adapted to the body mass index. Visually assessed image quality and attenuation measured in each coronary segment were retrospectively compared in 20 consecutive patients scanned with a normal-dose (ND, 40-105 ml) contrast protocol.
RESULTS
Visually assessed image quality did not differ significantly among protocols. By contrast, attenuation obtained from the ULD protocol (median contrast volume 35 ml) differed significantly from the LD (median 45 ml) and ND (median 70 ml) protocols in the coronary segments (316 ± 52 vs 363 ± 60 and 359 ± 52 HU, p < 0.001). Attenuation did not differ significantly between the LD and ND protocol. The proportion of patients with inadequate coronary vessel attenuation was significantly higher (p < 0.001) in the ULD protocol (37%) than in the ND (5%) and LD (10%) protocols but did not differ significantly between the ND and LD protocols.
CONCLUSION
In a clinical setting, a LD contrast protocol with a median volume of 45 ml is feasible for the latest generation 256-slice coronary CT angiography as it yields attenuation comparable to a ND protocol. By contrast, the implementation of an ULD protocol remains challenging. Advances in knowledge: Although not perceived by the naked eye, an ULD contrast protocol in a clinical setting yields attenuation below a threshold for diagnostic image quality.
Topics: Cardiac-Gated Imaging Techniques; Computed Tomography Angiography; Contrast Media; Female; Humans; Male; Middle Aged; Radiographic Image Interpretation, Computer-Assisted; Registries; Retrospective Studies; Triiodobenzoic Acids
PubMed: 28406318
DOI: 10.1259/bjr.20160933 -
Pediatric Cardiology Jun 2022Optimal enhancement of the Fontan pathway is crucial for the accurate CT evaluation. Current guidelines for contrast-enhanced CT protocols are rather inconsistent in...
Optimal enhancement of the Fontan pathway is crucial for the accurate CT evaluation. Current guidelines for contrast-enhanced CT protocols are rather inconsistent in scan delays and injection methods. This single-center, retrospective study was performed to compare objective measures of contrast enhancement between 1- and 3-min scan delays (41 and 36 patients, respectively) to determine a better contrast-enhanced CT protocols for evaluating the Fontan pathway. In both groups, a biphasic injection protocol, in which 50% diluted contrast agent (the amount of iodinated contrast agent: 2.0 mL/kg; the amount of saline: 2.0 mL/kg) was injected at the injection rate of 0.5‒2.5 mL/s for 50 s followed by a saline flush at the same injection rate (0.5‒2.5 mL/s), was used. The degree and heterogeneity of cardiovascular enhancement, image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were quantitatively evaluated. The mean densities of all cardiovascular structures were significantly higher in the 1-min delay protocol than in the 3-min delay protocols (p < 0.001). Heterogeneous enhancement (normalized standard deviation > 0.70) in the Fontan pathway was significantly more frequent in the 1-min delay protocol (p < 0.001). No significant differences were found in image noise (p > 0.141) and the frequency showing suboptimal noise (p = 1.000) between the two protocols. SNR and CNR were significantly lower in the 3-min delay protocol (p < 0.001). Compared with the 1-min delay protocol, the 3-min delay protocol achieved more homogeneous enhancement in the Fontan pathway on CT but showed lower contrast enhancement, SNR, and, CNR, indicating the need for further improvement.
Topics: Cardiovascular System; Contrast Media; Humans; Radiation Dosage; Retrospective Studies; Signal-To-Noise Ratio; Tomography, X-Ray Computed
PubMed: 35107628
DOI: 10.1007/s00246-022-02830-2 -
Veterinary and Comparative Oncology Sep 2018The standard of care treatment for canine lymphoma is multi-agent chemotherapy containing prednisolone, cyclophosphamide, vincristine and an anthracycline such as...
Evaluation of a multi-agent chemotherapy protocol combining lomustine, procarbazine and prednisolone (LPP) for the treatment of relapsed canine non-Hodgkin high-grade lymphomas.
The standard of care treatment for canine lymphoma is multi-agent chemotherapy containing prednisolone, cyclophosphamide, vincristine and an anthracycline such as doxorubicin (CHOP) or epirubicin (CEOP). Lomustine, vincristine, procarbazine, and prednisone (LOPP) has been evaluated as a rescue, with encouraging results; however, resistance to vincristine is likely in patients relapsing on CHOP/CEOP, and this agent may enhance LOPP toxicity without improving efficacy. The aim of this study was to evaluate responses to a modified-LOPP protocol that does not include vincristine (LPP) and is administered on a 21-day cycle. Medical records of dogs with high-grade multicentric lymphoma from 2012 to 2017 were reviewed. Dogs with relapsed lymphoma that received LPP as a rescue protocol were enrolled. Response, time from initiation to discontinuation (TTD) and toxicity of LPP were assessed. Forty-one dogs were included. Twenty-five dogs (61%) responded to LPP including 12 complete responses (CR) and 13 partial responses (PR). Responders had a significantly longer TTD (P < .001) compared to non-responders with 84 days for CR and 58 days for PR. Neutropenia was documented in 20 dogs (57%): 12 grade I to II, 8 grade III to IV. Thrombocytopenia was infrequent (20%): 5 grade I to II, 2 grade III to IV. Twelve dogs developed gastrointestinal toxicity (30%): 10 grade I to II and 2 grade III. Nineteen dogs had elevated ALT (59%): 9 grade I to II, 10 grade III to IV. Treatment was discontinued due to toxicity in 8 dogs (19%). The LPP protocol shows acceptable efficacy and toxicity-profile and minimizes in-hospital procedures.
Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Dog Diseases; Dogs; Female; Lomustine; Lymphoma, Non-Hodgkin; Male; Neutropenia; Prednisolone; Procarbazine; Recurrence; Treatment Outcome
PubMed: 29380942
DOI: 10.1111/vco.12387 -
Current Treatment Options in Oncology Dec 2001Despite tremendous advances in brain tumor molecular biology and several emerging novel therapies, multimodality therapy that includes surgery, radiation therapy (RT),... (Review)
Review
Despite tremendous advances in brain tumor molecular biology and several emerging novel therapies, multimodality therapy that includes surgery, radiation therapy (RT), and chemotherapy is still the cornerstone of high-grade glioma treatment. The first step in high-grade glioma therapy is surgery and a maximal resection should be attempted to reduce the tumor burden before initiation of other adjuvant therapies. External beam radiation therapy (EBRT) generally follows surgery, using conventional dosage, and fractionation, and ideally a three-dimensional conformal technique. Stereotactic radiosurgery (SRS) to maximize cytoreduction may be used in selected cases. Because no curative chemotherapy exists for high-grade glioma, we always consider an investigational agent either before or concurrently with RT. However, the use of a standard cytotoxic agent, such as temozolomide alone or combined with 13-cis-retinoic acid also is a rational choice particularly for patients with relatively good prognostic factors for whom an investigational agent would not be available. The management of anaplastic oligodendroglioma does not differ significantly from other high-grade gliomas in terms of surgery, RT, or investigational or protocol agent; however, these tumors appear to respond to chemotherapy that includes a combination of procarbazine, CCNU, and vincristine (PCV) [1**]. The vincristine provides more toxicity than benefit and it is our practice to only use a combination of procarbazine and CCNU (PC). A single agent, such as temozolomide is an increasingly used and rational choice for anaplastic oligodendroglioma. It is our belief that early, aggressive multimodality treatment still provides the best chance for long-term control of high-grade gliomas, particularly in patients with good prognostic factors. However, despite best therapy and state-of-the-art technology, most patients with high-grade glioma will experience progression or recurrence and will require either a change in the ongoing therapeutic strategy or additional treatment. Better therapies are necessary and progress will only be made through investigation of promising agents in well-designed clinical trials.
Topics: Adult; Antineoplastic Agents, Alkylating; Antineoplastic Combined Chemotherapy Protocols; Antioxidants; Brain Neoplasms; Chemotherapy, Adjuvant; Combined Modality Therapy; Contraindications; Cranial Irradiation; Craniotomy; Dacarbazine; Disease Progression; Epidemiologic Methods; Glioblastoma; Humans; Isotretinoin; Lomustine; Palliative Care; Procarbazine; Radiosurgery; Radiotherapy, Adjuvant; Radiotherapy, Conformal; Temozolomide; Treatment Outcome; Vincristine
PubMed: 12057096
DOI: 10.1007/s11864-001-0072-y -
Annals of Allergy, Asthma & Immunology... Aug 2004IgE-mediated carboplatin hypersensitivity reactions occur in up to 30% of patients receiving this agent for chemotherapy of solid tumors, thus limiting therapeutic...
BACKGROUND
IgE-mediated carboplatin hypersensitivity reactions occur in up to 30% of patients receiving this agent for chemotherapy of solid tumors, thus limiting therapeutic options.
OBJECTIVE
To describe our experience with intravenous carboplatin desensitization regimens, which culminated in a standardized, successful protocol for safe administration.
METHODS
Eight consecutive patients with ovarian cancer who had experienced severe anaphylactic reactions to carboplatin were referred to our hospital. Intradermal skin testing was performed by raising a 3-mm bleb by injection of undiluted carboplatin at 10 mg/mL, and the wheal size was read at 20 minutes. The outcomes of the various desensitization regimens were documented prospectively, and the experience gained was used to develop a standardized protocol for administration.
RESULTS
All patients had positive intradermal skin test results. The first 3 patients were treated with short (90 minutes to 6 hours) desensitization protocols, and all protocols failed on the first or second infusions. These 3 and a subsequent 5 patients were given intravenous carboplatin according to a protocol of gradual dose escalation over a 4-log dose range given during a 4-day period, with subsequent 3-weekly infusions given more rapidly by omitting the most dilute log dose on each occasion. All patients tolerated the longer infusion protocol without event, and all but 1 patient experienced appropriate tumor marker response.
CONCLUSIONS
Short carboplatin desensitization protocols (less than 6 hours) have an unacceptable failure rate in patients with carboplatin allergy, but longer infusion times (days) are well tolerated without recurrence of the allergic reaction and with good tumor response. In cases where carboplatin is the optimal therapeutic agent, clinicians should not be deterred by an anaphylactic reaction to it or by failure of shorter desensitization regimens.
Topics: Aged; Anaphylaxis; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Australia; Carboplatin; Desensitization, Immunologic; Dose-Response Relationship, Drug; Drug Hypersensitivity; Female; Humans; Infusions, Intravenous; Middle Aged; Neoplasm Staging; Ovarian Neoplasms; Paclitaxel; Skin Tests; Women's Health
PubMed: 15328672
DOI: 10.1016/S1081-1206(10)61465-2 -
Thoracic Surgery Clinics Nov 2006Since the advent of various novel immunosuppressants, including tacrolimus, rapamycin, and daclixumab. expanding variations of protocols have been developed. Little... (Review)
Review
Since the advent of various novel immunosuppressants, including tacrolimus, rapamycin, and daclixumab. expanding variations of protocols have been developed. Little evidence exists to substantially support a single agent over another. or a combination regimen protocol over another. Therefore, the principles and the goals of immunosuppression in lung transplantation recipients will remain moving targets and continue to evolve, and the use of large-scale, multi-institutional clinical trials is imperative to develop optimal immunosuppressive strategies.
Topics: Antimetabolites, Antineoplastic; Humans; Immunosuppression Therapy; Immunosuppressive Agents; Lung Transplantation; Lymphatic Irradiation; Photopheresis
PubMed: 17240827
DOI: 10.1016/j.thorsurg.2006.07.002 -
Trauma Monthly Aug 2015The main objectives of triage are securing patient safety during the process of emergency diagnosis and treatment, and reduction of waiting time for medical services and... (Review)
Review
CONTEXT
The main objectives of triage are securing patient safety during the process of emergency diagnosis and treatment, and reduction of waiting time for medical services and transport. To date, there is no triage system for nerve agent victims.
EVIDENCE ACQUISITION
This systematic review proposes a new triage system for patients exposed to nerve agents. Information regarding clinical signs and symptoms of intoxication with nerve agents, primary treatments, and classification of patients were extracted from the literature. All related articles were reviewed. Subsequently, specialists from different disciplines were invited to discuss and draft protocols.
RESULTS
Finalized triage tables summarizing the classification methods and required protocols in the field were designed after several meetings.
CONCLUSIONS
The proposed triage protocol encompasses aspects from most of the existing triage systems to create a single overarching guide for unifying the triage process. The proposed protocol can serve as a base for the designing future guidelines.
PubMed: 26543836
DOI: 10.5812/traumamon.16211 -
DICP : the Annals of Pharmacotherapy Feb 1991Altretamine is a National Cancer Institute-designated group C antineoplastic agent used in the treatment of advanced ovarian cancer. Altretamine is a highly... (Comparative Study)
Comparative Study Review
Altretamine is a National Cancer Institute-designated group C antineoplastic agent used in the treatment of advanced ovarian cancer. Altretamine is a highly lipid-soluble drug available only for oral administration as a capsule. The drug is activated through metabolic oxidation to intermediate methylol derivatives and formaldehyde. It is unclear which metabolite is the major species responsible for cytotoxicity or the primary mechanism of cytotoxicity. As a single agent in the treatment of ovarian cancer, altretamine demonstrates a response rate similar to other active agents in this disease (21-39 percent). The major utility of altretamine is in combination with other agents such as cyclophosphamide, doxorubicin, fluorouracil, melphalan, and cisplatin. However, few randomized trials have evaluated the contribution of altretamine in these multiagent combinations. Dose-limiting toxicities include gastrointestinal (nausea, vomiting, anorexia), hematologic, and neurotoxic (peripheral neurotoxicity). The therapeutic role of altretamine is limited because of a toxicity profile similar to that of cisplatin, one of the more active agents in ovarian cancer. Its use should be reserved for patients who are not candidates for more standard platinum-based regimens.
Topics: Altretamine; Antineoplastic Combined Chemotherapy Protocols; Cisplatin; Clinical Trials as Topic; Cyclophosphamide; Doxorubicin; Drug Interactions; Female; Fluorouracil; Humans; Lung Neoplasms; Methotrexate; Ovarian Neoplasms
PubMed: 1905441
DOI: 10.1177/106002809102500209 -
Nature Protocols Aug 2021The minimal inhibitory concentration (MIC) assay uses agar or broth dilution methods to measure, under defined test conditions, the lowest effective concentration of an... (Review)
Review
The minimal inhibitory concentration (MIC) assay uses agar or broth dilution methods to measure, under defined test conditions, the lowest effective concentration of an antimicrobial agent that inhibits visible growth of a bacterium of interest. This assay is used to test the susceptibilities of bacterial isolates and of novel antimicrobial drugs, and is typically done in nutrient-rich laboratory media that have little relevance to in vivo conditions. As an extension to our original protocol on MIC assays (also published in Nature Protocols), here we describe the application of the MIC broth microdilution assay to test antimicrobial susceptibility in conditions that are more physiologically relevant to infections observed in the clinic. Specifically, we describe a platform that can be applied to the preparation of medium that mimics lung and wound exudate or blood conditions for the growth and susceptibility testing of bacteria, including ESKAPE pathogens. This protocol can also be applied to most physiologically relevant liquid medium and aerobic pathogens, and takes 3-4 d to complete.
Topics: Animals; Anti-Bacterial Agents; Bacteria; Culture Media; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Spectrophotometry; Time Factors
PubMed: 34215865
DOI: 10.1038/s41596-021-00572-8