Research on the method of controlling the 99mTc-Technegas inhaled during 1-day pulmonary ventilation/perfusion imaging
Objective Our purpose was to establish a simple and feasible method for monitoring and controlling the 99mTc-Technegas inhaled to improve the success ratio of imaging and ensure the imaging quality. Materials and methods The relationship between the success ratio and the pulmonary ventilation counting rate (VCR) of 113 cases, the activity of perfusion imaging agents injected and the pulmonary perfusion counting rate (PCR) of another 114 cases were analysed retrospectively. And combined with the relationship between the surface radioactivity monitoring value and the SPECT probe counting rate of a pulmonary model, the effective range of the VCR and the surface radioactivity monitoring value were determined. Two hundred fifty cases with 99mTc-Technegas inhaled monitored and controlled were used to verify the reliability and practicability of this method. Results The VCR of the ventilation/perfusion imaging with deep venous thrombosis imaging and the ventilation/perfusion imaging without deep venous thrombosis imaging was in 1.0–3.0 kct/s and 1.0–2.0 kct/s when the monitoring values of handheld radiation monitor was within the range of 60–170 µSv/h and 60–110 µSv/h, respectively. The success ratio of the V/Q-Only increased from 48.9% (43/88) of the control group to 80.8% (122/151) of the experimental group. The VCR in the two groups was examined by the non-parametric Mann–Whitney U test (P
Conclusions: In this pilot study, we have demonstrated the feasibility and potential utility of V/Q PET/CT for the management of patients with suspected acute PE. V/Q PET/CT may be of particular relevance in cases of equivocal findings or isolated subsegmental findings on CTPA, adding further discriminatory information to allow important decision-making regarding application or withholding of treatment courses of therapeutic anticoagulation, which may confer an increased risk of bleeding. Given the other advantages of V/Q PET/CT (reduced acquisition time, low radiation dose), and with increasing availability of 68Ga-genera...
Conclusion: Hybrid SPECT/CT (Q) imaging has a high diagnostic accuracy for detecting PTE than planar (Q) scans interpreted with chest radiographs. In addition, low dose CT used in SPECT/CT was able to identify other non-embolic pathologies (eg: pneumonia, emphysematous bullae, tumor or lymphadenopathy) responsible for perfusion defects which could have been missed on chest radiography thereby increasing the specificity. Modified PIOPED II had a higher number of non-diagnostic results compared to PISAPED which increases the latter's clinical utility.
Conclusion Our study showed that the omission of a ventilation SPECT led to a high rate of false-positive diagnoses and that the ventilation scan cannot be replaced by a chest radiography.
Conclusion In this case series, a large proportion of patients with isolated SSPE on V/Q imaging were not identified on corroborating CTPA performed within 48 h. In patients with isolated SSPE (identified by isolated subsegmental mismatch on V/Q single-photon emission computed tomography), we found no difference in risk of recurrent suspected VTE or all-cause mortality in those treated with anticoagulation and those not treated.
Conclusions: Detailed pulmonary ventilation to perfusion mismatch in PTE, PE, and PID patients was quantified calculating %VPM from pulmonary ventilation and perfusion SPECT images. All analyzed disease may have recognizable VPM. Moreover, %VPM cannot differentiate PTE and PE patients.
We present a case of severe idiopathic pulmonary arterial hypertension in a 20-year-old patient with ongoing breathlessness. She was initially diagnosed with asthma and panic attacks in community care. As the symptoms became progressively worse, she was referred for pulmonary hypertension clinic assessment. Ventilation/perfusion single-photon emission computed tomography (V/Q SPECT) showed grossly abnormal perfusion defects which were mismatched to the ventilation scan, suggestive of chronic thromboembolic disease.
The use of ventilation/perfusion SPECT scans to rule out pulmonary embolism...Read more on AuntMinnie.comRelated Reading: Video from ECR 2017: Dr. Martine Rémy-Jardin on pulmonary embolism Ultrasound elevates diagnosis of pulmonary embolism Triple rule-out CT offers one-stop shop for chest pain Can ultrasound for deep vein thrombosis cause a PE? Societies issue imaging guidelines for chest pain
Semin Thromb Hemost DOI: 10.1055/s-0036-1598007 Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.Article in Thieme eJournals: Table of contents | Full text
Chronic thromboembolic pulmonary hypertension (CTEPH) is the only potentially curable form of pulmonary hypertension. Rapid and accurate diagnosis is pivotal for successful treatment. Clinical signs and symptoms can be nonspecific and risk factors such as history of venous thromboembolism may not always be present. Echocardiography is the recommended first diagnostic step. Cardiopulmonary exercise testing is a complementary tool that can help to identify patients with milder abnormalities and chronic thromboembolic disease, triggering the need for further investigation. Ventilation/perfusion (V'/Q') scintigraphy is the ima...