Unusual Breast Metastasis from Atypical Lung Carcinoid on 68Ga-DOTATATE PET/CT

BACKGROUND

Atypical carcinoid (AC) is one of the rarest lung neuroendocrine tumors (NETs) that rarely metastasize to the breast, and only a few cases have been reported in the literature. Positron emission tomography/computed tomography (PET/CT) with somatostatin analogs (SSAs) labeled with Gallium-68 (68Ga) now represents the gold standard for diagnosis and management of NETs. A case of an unusual metastasis to the breast from an AC detected by 68Ga-DOTATATE PET/CT was reported.

CASE PRESENTATION

A 73-year-old woman was presented with a right breast lesion found on mammography screening, which revealed a metastatic neuroendocrine tumor by histopathological analysis with a tru-cut biopsy. Subsequently, 68Ga-DOTATATE PET/CT imaging performed for the initial evaluation showed increased radiotracer uptake in the lesion in the right breast as well as the nodular lesion in the middle lobe of the right lung, which was histologically confirmed to be AC.

CONCLUSION

Metastasis of uncommon AC of the lung to the breast is extremely rare. However, it is essential to properly differentiate metastatic tumors from primary disease due to differences in clinical management and prognosis, and 68Ga-DOTATATE PET/CT is a unique diagnostic tool with the advantage of whole-body imaging.

Impact of 68Ga-PSMA PET/CT on Survival and Management in Prostate Cancer

BACKGROUND

68Ga-labeled prostate-specific membrane antigen positron emission tomography-computed tomography (68Ga-PSMA PET/CT) has led to altered treatment plans for prostate cancer (PCa) patients.

OBJECTIVE

This study aimed to investigate the impact of 68Ga-PSMA PET/CT on overall survival (OS) and management in PCa.

METHODS

Consecutive 100 patients who had 68Ga-PSMA PET/CT and conventional imaging (CI) were included in this retrospective study. Disease stages and treatment plans according to both CI and 68Ga-PSMA PET/CT were compared. The effect of 68Ga-PSMA PET/CT on OS was assessed.

RESULTS

After 68Ga-PSMA PET/CT, the stage changed in 64 patients (64%). By the reason of 68Ga-PSMA PET/CT findings, treatment plans based on CI were changed in 73 patients (73%). According to the ROC analysis, patients with a PSA value below 8 had higher rates of change in staging (p<0.0001) and treatment (p=0.034). Both a PSA below 8 (OR 8.79 95% CI (2.72-28.43), p<0.001), and having a hormone-sensitive disease at the time of imaging (OR 5.6 95% CI (1.35-23.08), p=0.017) were significant independent factors predicting change in staging with 68Ga-PSMA PET/CT. The results of a phi correlation coefficient analysis showed a significant relationship between therapy and changes in staging (ϕ=0.638, p<0.0001). Two-year OS was statistically different in hormone-sensitive patients with and without treatment change (95% vs 81%, p=0.006).

CONCLUSION

68Ga-PSMA PET/CT has the effect of changing the treatment in 73% of PCa patients. There is a positive correlation between the changes in staging and treatment. Survival of hormone sensitive patients has improved due to treatment changes based on PET/CT findings.

The Sentinel Node and Occult Lesion Localization (SNOLL) Technique Using a Single Radiopharmaceutical in Non-palpable Breast Lesions

BACKGROUND

In order to perform a full surgical resection on non-palpable breast lesions, a current method necessitates correct intraoperative localization. Additionally, because it is an important prognostic factor for these patients, the examination of the lymph node status is crucial.

OBJECTIVE

The aim of this study was to evaluate the efficiency of the sentinel node and occult lesion localization (SNOLL) technique in localizing nonpalpable breast lesions together with sentinel lymph node (SLN) using a single radiotracer, that is, nanocolloid particles of human serum albumin (NC) labeled with technetium-99m (99mTc).

METHODS

39 patients were included, each having a single non-palpable breast lesion and clinically no evidence of axillary disease. Patients received 99mTc- NC intratumorally on the same day as surgery under the guidance of ultrasound. Planar and single-photon emission computed tomography/computed tomography lymphoscintigraphy were performed to localize the breast lesion and the SLN. The occult breast lesion and SLN were both localized using a hand-held gamma-probe, which was also utilized to determine the optimal access pathway for surgery. In order to ensure a radical treatment in a single surgical session and reduce the amount of normal tissue that would need to be removed, the surgical field was checked with the gamma probe after the specimen was removed to confirm the lack of residual sources of considerable radioactivity.

RESULTS

Breast lesions were successfully localized and removed in all patients. Pathological findings revealed breast carcinoma in 11/39 patients (28%) and benign lesions in 28 (72%). Axillary SLNs were detected in 31/39 (79.5%) patients. The metastatic involvement of SLN was only seen in two cases.

CONCLUSION

While the identification rate of the SNOLL technique performed with an intratumoral injection of 99mTc-NC as the sole radiotracer in non-palpable breast lesions was great, it was not fully satisfactory in SLNs.

Uptake of 68 Ga-PSMA in Avascular Necrosis of the Femoral Head in a Patient With Prostate Cancer

ABSTRACT

A 69-year-old man with prostate cancer treated with radical prostatectomy underwent 68 Ga-PSMA PET/CT due to biochemical recurrence. Increased radiotracer uptake in the prostate bed suggestive of local recurrence was detected. The right hip also displayed increased 68 Ga-PSMA activity, which was consistent with the avascular necrosis findings on MRI.

Detection of COVID-19 Incidentally in 68Ga-PSMA PET/CT for Restaging of Prostate Cancer

BACKGROUND

A series of pneumonia cases with clinical presentations of viral pneumonia secondary to new coronavirus and subsequent global transmission arose in Wuhan, Hubei, China, in December 2019. Several cases of coronavirus disease 2019 (COVID-19) have been described incidentally in positron emission tomography-computed tomography (PET/CT) with ¹⁸F-fluorodeoxyglucose (FDG) as a result of the pandemic. Herein, we describe the findings of a patient with unknown COVID-19 in PET/CT with the other radiopharmaceutical, ⁶⁸Ga-labeled prostatespecific membrane antigen (⁶⁸Ga-PSMA).

CASE REPORT

A 69-year-old man had previously undergone radical prostatectomy for adenocarcinoma. ⁶⁸Ga-PSMA PET/CT imaging was performed due to biochemical recurrence. ⁶⁸Ga-PSMA uptake in the prostate bed suggestive of local recurrence was detected in PET/CT images. Also, bilateral groundglass opacities with slightly increased ⁶⁸Ga-PSMA uptake were seen in the lungs, suspected of COVID-19. A reverse transcription-polymerase chain reaction test has confirmed the infection.

CONCLUSION

Even in asymptomatic patients, nuclear medicine departments must be aware of the possibility of COVID-19, take appropriate post-exposure procedures, and protect employees and other patients.

Parathyroid Hormone on Osteoprotegerin Levels in Patients with Primary Hyperparathyroidism

OBJECTIVE

Osteoprotegerin is a glycoprotein that plays a major role in the regulation of bone turnover. The influence of parathyroid hormone, an important regulator of bone remodeling, on osteoprotegerin production is controversial. The purpose of the study was to assess the influence of parathyroid hormone on the circulating level of osteoprotegerin in patients with primary hyperparathyroidism by comparing it with healthy controls.

MATERIALS AND METHODS

Forty-four patients with biochemical verification of primary hyperparathyroidism scheduled for the surgical cure and 38 healthy subjects were included. Blood samples of the study group were taken before surgery. Levels of serum parathyroid hormone, osteoprotegerin, calcium, 25-hydroxyvitamin D [25(OH)D], and alkaline phosphatase were analyzed. Bone mineral density at the L1-L4 vertebrae and femoral neck was calculated by dual-energy X-ray absorptiometry.

RESULTS

Osteoprotegerin levels and bone mineral density values were significantly lower in patients than in the healthy subjects (P=.002 and P > .0001, respectively). There was no correlation between osteoprotegerin and parathyroid hormone in the groups. Osteoprotegerin was weakly correlated with bone mineral density in patients. No correlation was noted between osteoprotegerin and bone mineral density in the control group. Furthermore, osteoprotegerin levels were not correlated with calcium, 25(OH)D, and alkaline phosphatase levels in each group.

CONCLUSION

The production of osteoprotegerin appears to be inhibited by parathyroid hormone in patients with primary hyperparathyroidism. A weak positive correlation found among osteoprotegerin and bone mineral density recommends that osteoprotegerin may be a molecule that impacts bone metabolism and finally bone mineral density.

The Value of 99mTc-MIBI SPECT/CT in the Postoperative Assessment of Patients with Differentiated Thyroid Carcinoma

BACKGROUND

The therapeutic approaches of differentiated thyroid carcinoma (DTC) are surgery, ablation therapy with the postoperative use of radioiodine-131 (131I), and thyroid-stimulating hormone (TSH) suppression therapy. After the surgical therapy, the patient should be assessed for remnants/metastases.

OBJECTIVE

The purpose of this research was to investigate the role of technetium-99m-methoxyisobutylisonitrile (99mTc-MIBI) single photon emission computed tomography/computed tomography (SPECT/CT) in the postoperative management of patients with DTC.

METHODS

The study comprised 22 DTC patients (13 women, 9 men; mean age 46.55 ± 13.27 y) who underwent a total thyroidectomy previously. All patients were investigated for thyroid remnants/metastases by 99mTc-MIBI SPECT/CT, posttherapy 131I whole-body scan (WBS) and ultrasound (US). Serum TSH, thyroglobulin and anti-Tg antibody levels were measured. Results of imaging modalities and laboratory measurements were compared with each other.

RESULTS

99mTc-MIBI SPECT/CT, 131I WBS and US respectively demonstrated thyroid remnants in 15 (68.18%), 22 (100%) and 14 (63.63%) of the all patients and metastatic lymph nodes in 8 (100%), 6 (75%) and 6 (75%) of the 8 patients with lymph node metastases. 99mTc-MIBI SPECT/CT also demonstrated lung metastases in 2 patients (9.09% of all patients). The same result was obtained with 131I WBS.

CONCLUSION

The findings of this study show that 99mTc-MIBI SPECT/CT can be effective for detecting metastases in patients with DTC who underwent surgery prior to 131I therapy.

Assessment of volumetric parameters derived from 68Ga-PSMA PET/CT in prostate cancer patients with biochemical recurrence: an institutional experience

OBJECTIVE

The aim of this study was to evaluate the relationship between volumetric parameters calculated using semiautomatic quantification of lesions detected in 68Ga-labeled prostate-specific membrane antigen PET-computed tomography (68Ga-PSMA PET/CT) and clinical characteristics in prostate cancer (PCa) patients with biochemical recurrence.

METHODS

A total of 85 consecutive PCa patients with biochemical recurrence who underwent 68Ga-PSMA PET/CT at our institution from January 2019 to March 2020 were retrospectively assessed. 68Ga-PSMA PET/CT-derived volumetric parameters, including whole-body PSMA tumor volume (wbPSMA-TV) and whole-body total lesion PSMA (wbTL-PSMA), as well as the established maximum and mean standardized uptake value (SUVmax and SUVmean), were calculated for each patient. All PET-derived parameters were analyzed for correlation with prostate-specific antigen (PSA) levels and for association with Gleason scores.

RESULTS

Eighty-five patients with a mean age of 68.9 ± 7.8 years (range, 47-83 years) and a mean PSA level of 40.9 ± 92.1 ng/ml (range, 0.2-533.2 ng/ml) were analyzed. Volumetric parameters, that is, wbPSMA-TV and wbTL-PSMA, demonstrated a statistically significant correlation with PSA levels (r = 0.403 and r = 0.556, respectively, all at P < 0.001) and only the means of wbTL-PSMA were significantly different between the Gleason score groups (P < 0.05).

CONCLUSIONS

The results of our study indicate that 68Ga-PSMA PET/CT might be a valuable tool for the detection and follow-up of recurrence in PCa patients. 68Ga-PSMA PET/CT-derived quantitative volumetric parameters demonstrated a highly significant correlation with changes in PSA levels. Larger prospective studies are needed to help reveal the full potential of parameters such as PSMA-TV and TL-PSMA derived from PET imaging with 68Ga-PSMA.

Baseline 18F-FDG PET textural features as predictors of response to chemotherapy in diffuse large B-cell lymphoma

PURPOSE

We sought to investigate the performance of radiomics analysis on baseline 18F-FDG PET/CT for predicting response to first-line chemotherapy in diffuse large B-cell lymphoma (DLBCL).

MATERIAL AND METHODS

Forty-five patients who received first-line rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) chemotherapy for DLBCL were included in the study. Radiomics features and standard uptake value (SUV)-based measurements were extracted from baseline PET images for a total of 147 lesions. The selection of the most relevant features was made using the recursive feature elimination algorithm. A machine-learning model was trained using the logistic regression classifier with cross-validation to predict treatment response. The independent predictors of incomplete response were evaluated with multivariable regression analysis.

RESULTS

A total of 14 textural features were selected by the recursive elimination algorithm, achieving a feature-to-lesion ratio of 1:10. The accuracy and area under the receiver operating characteristic curve of the model for predicting incomplete response were 0.87 and 0.81, respectively. Multivariable analysis revealed that SUVmax and gray level co-occurrence matrix dissimilarity were independent predictors of lesions with incomplete response to first-line R-CHOP chemotherapy.

CONCLUSION

Increased textural heterogeneity in baseline PET images was found to be associated with incomplete response in DLBCL.

The role of serum osteoprotegerin level in diagnosis of disease and determining cardiovascular risk of polycystic ovary syndrome

Objective: Although animal studies claim that osteoprotegerin (OPG) is preventive on this system, there are conflicting results in human studies. The aim of this study was to investigate the role of OPG in the diagnosis and determination of cardivovascular risk in patients with polycystic ovary syndrome (PCOS), which is a multisystem effective disease.Method: The study was performed on 28 premenopausal healthy female volunteers and 57 newly diagnosed PCOS patients in 2017. Anamnesis was obtained, body mass indexes were calculated, laboratory tests required for diagnosis and differential diagnosis of PCOS and suprapubic ovarian ultrasonography were performed, serum OPG level was studied by enzyme-linked immunosorbent assay.Results: OPG levels were similar in PCOS and control groups and there was no significant difference (49.392 ± 10.973 pg/ml vs 49.567 ± 13.57 pg/ml, p = .815). Correlation analysis showed a positive correlation between OPG and total testosterone levels in the PCOS group (r = 0.277, p = .045). No significant relationship with cardiovascular and metabolic parameters was detected.Conclusion: No difference was found between PCOS patients and control groups in terms of OPG levels. Therefore, it is thought that OPG level cannot be used in the diagnosis of the disease. There was no significant relationship between cardiometabolic parameters.

Single-photon Emission CT Combined with Spiral CT for Early Detection and Localization of Bone Metastasis: A Review

BACKGROUND

Bone metastasis is common in cancer. Evaluating the metastatic status in cancer is of utmost importance in order to provide the best patient's management.

DISCUSSION

Bone scintigraphy is widely used for evaluation of bone metastasis. It has high sensitivity with limited specificity. Planar bone scintigraphy has been shown to have increased radiotracer uptake without accurate anatomic localization and characterization. Hybrid Single-Photon Emission Computed Tomography/Computerized Tomography (SPECT/CT) system has been developed by combination of SPECT and CT. Accurate lesion localization and discrimination of equivocal bone lesions is an advantage in this hybrid technique. It improves diagnostic accuracy by differentiation of benign bone lesions from malignant ones due to their morphological changes. So, SPECT/CT improves the specificity of bone scintigraphy leading to better outcomes in diagnosis and treatment outcomes of bone metastatic cancer patients.

CONCLUSION

In here, we discussed the prognostic value of bone scintigraphy and SPECT/CT in bone metastasis with our clinical experience and review of the literature.

Effects of chronic sleep deprivation on upper respiratory tract mucosal histology and mucociliary clearance on rats

In this study, we aimed to investigate the effects of chronic sleep deprivation on mucociliary clearance, which is the primary defence mechanism of the upper airway tract and nasal mucosal histology. Forty-two Wistar Albino rats (250-300 g), 8 or 12 weeks old, were randomly assigned into three groups as follows. The first sleep-deprivation group consisted of 14 rats (A), another 14 of them were assigned to platform group (B), and the remaining 14 were included to the home cage control group (C). For the two deprivation groups (A and B), the modified multiple platform method (MMPM) was used to induce sleep deprivation for 21 days. Tc-99m MAA rhinoscintigraphy was performed to assess mucociliary clearance and the nasal histopathological changes of the sacrificed rats were also examined. Mucociliary clearance was significantly higher in sleep deprivation (A) and deprivation control (B) groups than the control group (C) (p = .037). The ratio of columnar ciliary was significantly higher in group A and B than in the control group (p = .003). The transitional epithelial ratio in groups A and B was also significantly increased compared with group C (p = .04). The control group's squamous epithelial ratio was increased compared to the sleep-deprived groups (p = .003). There was a significantly increased inflammatory response in the ciliated columnar epithelium in groups A and B compared to group C (p = .02). For the first time in the literature, we demonstrated that chronic sleep deprivation has caused a significant increase in mucociliary clearance speed and in the number of ciliary cells.

Diagnostic Value of Bone SPECT/CT in Patients with Suspected Osteomyelitis

Objectives

The aim of our retrospective study was to evaluate the contribution of single photon emission computed tomography/computed tomography (SPECT/CT) to three phase bone scintigraphy/SPECT for the assessment of osteomyelitis (OM) and patient’s management.

Methods

Eighty-five patients who were suspected as having OM were included in this study. Tc-99m MDP three phase bone scintigraphy and SPECT/CT were performed to the region of suspected OM. SPECT/CT findings were compared with the findings of planar images/SPECT. Both planar bone scan/SPECT and SPECT/CT findings were divided into two groups: With OM and without OM. In all patients, scintigraphic diagnosis was confirmed by clinical follow up, laboratory findings, microscopic-bacteriological examinations, radiological, surgical, and pathological findings.

Results

SPECT/CT changed the diagnosis and treatment planning in 14/85 (16.5%) patients. SPECT/CT was significantly superior to planar scan/SPECT imaging for determining OM (kappa value was 0.626 for planar scan/SPECT, 0.929 for SPECT/CT). SPECT/CT was statistically more successful in detection of chronic OM, and useful in differentiating chronic OM from acute OM (kappa value was 0.541 for planar scan/SPECT, 0.944 for SPECT/CT).

Conclusion

SPECT/CT increases accuracy of the diagnosis in the evaluation of OM when it is compared to three phase bone scintigraphy/SPECT. SPECT/CT can change the diagnosis and management of the patients.

A Case of Hypertrophic Pulmonary Osteoarthropathy in Both Upper and Lower Extremities: A Rare Involvement

Hypertrophic pulmonary osteoarthropathy (HPOA) is a paraneoplastic manifestation of gastric and, more frequently, lung carcinomas. It is characterized by extremity pain, clubbing, arthritis and periostitis of the long bones. Periostitis is the hallmark of HPOA and can be revealed with bone scintigraphy. Whole-body bone scintigraphy (WBBS) is very sensitive during the active lesion period and WBBS findings usually precede that of plain radiography. WBBS can also show improvement in the first 6 months following treatment, thus making it an important technique in the management and follow-up of these patients. While HPOA findings are usually seen in the lower extremities, involvement of both upper and lower extremities is a rare condition. In this case report, it is aimed to present findings of a 67-year-old male patient with lung cancer and complaint of extremity pain. We report on this patient to draw attention to HPOA of both upper and lower extremities.

The Contribution of SPECT/CT in the Diagnosis of Stress Fracture of the Proximal Tibia

Stress fractures are injuries most commonly seen in the lower limbs and are usually caused by repetitive stress. While the distal and middle third of the tibia is the most frequent site for stress fractures (almost 50%), stress fractures of the proximal tibia is relatively rare and could be confused with other types of tibial fractures, thus altering management plans for the clinician. Early diagnosis of stress fractures is also important to avoid complications. Imaging plays an important role in the diagnosis of stress fractures, especially bone scan. Combined with single-photon emission computed tomography/computed tomography (SPECT/CT) it is an important imaging technique for stress fractures in both upper and lower extremities, and is widely preferred over other imaging techniques. In this case, we present the case of a 39-year-old male patient diagnosed with stress fracture of the proximal tibia and demonstrate the contribution of CT scan fused with SPECT imaging in the early diagnosis of stress fracture prior to other imaging modalities.

DEXA analysis on the bones of rats exposed in utero and neonatally to static and 50 Hz electric fields

Effects of the electromagnetic fields on living bodies, bones in particular, are among the relevant issues of contemporary life. In this study, we report the influences of 50 Hz and 0 Hz (static) electric fields (EF), on intact rat bones, as evaluated by dual energy X-ray absorbtion (DEXA) measurements on bone content and density when these animals (n = 27) are continuously exposed in utero and neonatally to EFs (10 kV/m) 14 days before and 14 days after their birth, for 28 days in total. Differences between 50 Hz EF and static EF groups are found to be significant (95% confidence level) for total bone mineral content (BMC), TBMC (P = .002). Differences between 50 Hz and control groups are found to be significant for total bone mineral density (BMD), TBMD (P = .002), lumbar BMC, LBMC (P = .023), and TBMC (P = .001). Differences between static EF and control groups are found to be significant for femoral BMD, FBMD (P = .009), TBMD (P = .002), LBMC (P = .001), and TBMC (P = .001). Note that TBMC parameters are jointly significant for all differences between the three groups of test animals. These results have shown that both static and 50 Hz EFs influence the early development of rat bones. However, the influence of static EFs is more pronounced than that of the 50 Hz field.

Lymphoscintigraphic drainage of acral limb skin to interval sentinel lymph nodes in healthy subjects

BACKGROUND AND OBJECTIVES

In the literature, drainage to epitrochlear and popliteal sentinel lymph nodes (SLN) are analyzed for whole or distal extremity (below elbow or knee) melanomas that are not topographically homogeneous with respect to tendency of drainage to interval SLNs. We hypothesize that acral (hand and foot) skin has a uniform frequency of drainage to interval SLNs, which is higher than reported for distal extremity melanomas.

METHODS

One hundred healthy subjects were enrolled. Fifty subjects had standard four extremity lymphoscintigraphies by radiocolloid injection into an interdigital web space as in lymphodynamic studies. On another 50 subjects, either targeted upper (n = 25) or lower (n = 25) extremity lymphoscintigraphies were performed utilizing injection sites that likely drain to interval SLNs. Acral skin drainage to interval SLNs was analyzed for interindividual variability and injection site dependence.

RESULTS

There was considerable interindividual variability in drainage of each injection site to interval SLNs. Hand skin had a uniform 50% frequency of drainage to epitrochlear-midhumeral SLNs with both injection sites. This frequency was higher than the epitroclear SLN frequencies reported for distal extremity melanomas. Foot skin had 10% and 90% frequencies of drainage to popliteal SLNs from standard and targeted injection sites, respectively. Foot skin largely simulates the tendency of drainage reported for distal extremity melanomas while lateral heel represents a limited zone that almost uniformly drains to popliteal SLNs.

CONCLUSIONS

Despite dissimilarities between hand and foot, acral skin drainage to interval SLNs is high enough to obligate a thorough interval SLN exploration in acral primaries.

Detection of alveolar epithelial injury by Tc-99m DTPA radioaerosol inhalation lung scan in rheumatoid arthritis patients

Rheumatoid arthritis (RA) is a systemic autoimmune disorder primarily involving the joints. Lung alterations in RA may be primary or secondary to pharmacological treatments and may involve the alveoli, interstitium, airways and/or pleura. Technetium-99m diethylenetriaminepentaacetic acid (Tc-99m DTPA) aerosol inhalation scintigraphy is a sensitive and noninvasive test commonly employed to assess pulmonary epithelial membrane permeability. The purpose of the this study was a) to investigate the changes of pulmonary alveolar epithelial permeability in patients with RA, b) to determine the relationship between the clearance rate of Tc-99m DTPA and pulmonary function test (PFT) results, and c) to determine the relationship between the clearance rete of Tc-99m DTPA and clinical parameters of disease. Twenty-five patients with RA but without lung alterations were included in the study. The patients were 22 females, and 3 males; mean age 53.6 +/- 8.7 years. Technetium-99m DTPA aerosol inhalation scintigraphy was performed on the study and healthy control groups. Clearance half times (T1/2) were calculated by placing a mono-exponential fit on the curves. Penetration index (PI) was calculated on the first-minute image. There were no significant differences in the mean T1/2 or mean PI values between the RA patients and control subjects. No correlation was found between the mean T1/2 values of Tc-99m DTPA clearance and activity of RA, clinical values, or the spirometric measurements except FEV1/FVC and functional status in RA patients (p = 0.02, p = 0.01, respectively). However, a weak correlation was found between duration of disease and T1/2 values of Tc-99m DTPA clearance (p = 0.006). PI values tended to correlate with FEF25-75, although, this was not statistically significant (p = 0.057). This study shows that no changes occur in alveolar-capillary permeability in RA patients without lung alterations.

Evaluation of the effect of trimetazidine on Tc-99m methoxyisobutyl isonitrile gated scintigraphy in patients with coronary artery ectasia

OBJECTIVE

Coronary artery ectasia (CAE) is the abnormal dilatation of a segment of the coronary artery to a diameter of at least 1.5 times that of normal adjacent segments. Symptoms are variable, and its prognosis and treatment modalities are unclear. The aim of this study is to evaluate the effect of trimetazidine (TMZ) on ischemic left ventricular function by rest-stress Tc-99m methoxyisobutyl isonitrile (Tc-99m MIBI) myocardial scintigraphy in symptomatic patients with CAE.

METHODS

We included patients with ectasia admitted to our Cardiology Department, Turkey, between 2003 and 2004 in this study. All patients underwent coronary angiography and diagnosed with CAE, before and 4 weeks after TMZ administration. Seventeen patients (9 men, 8 women) underwent gated single-proton emission tomographic (SPECT) using Tc-99m MIBI. We performed quantitative global and regional ventricular functional analysis using quantitative gated SPECT software.

RESULTS

The global ejection fraction increased from 59.9%+/-8.9% to 62.6%+/-8.3% after therapy (p=0.033). In addition, the end systolic volume and the end diastolic volume decreased after therapy (101.7+/-23.5 ml to 95.1+/-22.9 ml, p=0.002; from 41.1+/-14.3 to 36.4+/-13.6, p=002). In all segments, we observed significant post-therapy increases in relative tracer uptake. Percentage of MIBI uptake was 71.2+/-15.3 at baseline stress and 73.2+/-15 post-TMZ (p=0.001). As global function parameters, the total wall motion normal areas changed significantly (67-74% p=0.01) after therapy, but the total wall thickness did not changed significantly(49-45%, p=0.21).

CONCLUSION

The results of this study demonstrate that TMZ improves myocardial function by rest-stress Tc-99m MIBI gated SPECT during stress-induced ischemia in patients with CAE. Also, the outcomes revealed improvement in functional parameters, and percentage of MIBI uptake post TMZ administration. We can use this procedure to monitor the effect of TMZ in CAE patients.

Detection of alveolar epithelial injury by Tc-99m DTPA radioaerosol inhalation lung scan in rheumatoid arthritis patients

Rheumatoid arthritis (RA) is a systemic autoimmune disorder primarily involving the joints. Lung alterations in RA may be primary or secondary to pharmacological treatments and may involve the alveoli, interstitium, airways and/or pleura. Technetium-99m diethylenetriaminepentaacetic acid (Tc-99m DTPA) aerosol inhalation scintigraphy is a sensitive and noninvasive test commonly employed to assess pulmonary epithelial membrane permeability. The purpose of the this study was a) to investigate the changes of pulmonary alveolar epithelial permeability in patients with RA, b) to determine the relationship between the clearance rate of Tc-99m DTPA and pulmonary function test (PFT) results, and c) to determine the relationship between the clearance rete of Tc-99m DTPA and clinical parameters of disease. Twenty-five patients with RA but without lung alterations were included in the study. The patients were 22 females, and 3 males; mean age 53.6 +/- 8.7 years. Technetium-99m DTPA aerosol inhalation scintigraphy was performed on the study and healthy control groups. Clearance half times (T1/2) were calculated by placing a mono-exponential fit on the curves. Penetration index (PI) was calculated on the first-minute image. There were no significant differences in the mean T1/2 or mean PI values between the RA patients and control subjects. No correlation was found between the mean T1/2 values of Tc-99m DTPA clearance and activity of RA, clinical values, or the spirometric measurements except FEV1/FVC and functional status in RA patients (p = 0.02, p = 0.01, respectively). However, a weak correlation was found between duration of disease and T1/2 values of Tc-99m DTPA clearance (p = 0.006). PI values tended to correlate with FEF25-75, although, this was not statistically significant (p = 0.057). This study shows that no changes occur in alveolar-capillary permeability in RA patients without lung alterations.

Determination of inflammation of reflex sympathetic dystrophy at early stages with Tc-99m HIG scintigraphy: preliminary results

The pathogenesis of reflex sympathetic dystrophy (RSD) is not completely understood. However, an excessive regional inflammation, sensitization of primary somatosensory afferents, and sensitization of spinal neurons are considered to have a role in the pathogenesis of RSD. The underlying pathophysiology relating the clinical picture may help to determine the pharmacotherapeutic approach for an individual patient. Scintigraphy using radiolabelled human polyclonal non-specific immunoglobulin (HIG) has been recognized as a useful tool for the localization of inflammatory disorders. Thirty-six consecutive RSD patients associated with hemiplegia were included in this study. All the patients in this study had three phases bone scan and Tc-99m HIG scintigraphy. On admission, of 36 patients with positive bone scan, 30 had positive Tc-99m HIG scan. All the patients were symptomatic at the time of bone scanning. On the contrary, 24 out of 36 patients subsequently became asymptomatic at an 8-month re-evaluation period. Tc-99m HIG scintigraphy is a non-invasive complementary method for the determination of ongoing inflammatory reactions which also aids the clinicians to predict the response to anti-inflammatory therapy at the very early phase of RSD associated with hemiplegia. This preliminary study may be a source of inspiration for further studies with larger series and longer follow-up .

Evaluation of joints using Tc 99m-MDP bone scintigraphy in patients with familial Mediterranean fever: should bone scans be used for diagnosis and follow-up?

Familial Mediterranean fever (FMF) is an autosomal recessively-inherited disorder typically manifested by recurrent attacks of fever and polyserositis. The articular disease occurs in 50-70% of patients. Bone scintigraphy is more sensitive in the diagnosis of arthritis than clinical examination or conventional radiological imaging, allowing earlier diagnosis through the visualization of disease in multiple sites. To assess joint involvements in FMF patients with or without joint symptoms, bone scintigraphy was performed in 36 patients with FMF and in 25 controls. There was arthritis in 72% of patients. Of these, 65% knee, 42% ankle, 50% sacroiliac, 8% elbow, 8% wrist, 4% sternoclavicular and 4% hip involvements were found. The sacroiliac joints with sacroiliac index higher than 1.34 were diagnosed as sacroiliitis, which was higher than 2 SD of normal. FMF is frequently associated with joint disease such as knee and ankle arthritis and sacroiliitis. This high incidence of sacroiliitis in our study has not been previously reported. This difference could be explained by the different methodology used for the screening of the joints. Thus, we recommend that bone scintigraphy can be used in patients with FMF to determine the presence of arthritis, especially in sacroiliac joints, even asymptomatic.

The predictive value of additional late blood pool imaging to the three-phase bone scan in the diagnosis of reflex sympathetic dystrophy in hemiplegic patients

Reflex sympathetic dystrophy (RSD) is a relative common sequel after hemiplegia. The diagnosis of RSD in hemiplegic patients presents difficult clinical problems, as the symptoms and signs of RSD are not specific and RSD may be due to reasons other than hemiplegia. Bone scintigraphy has been routinely used for the diagnosis of RSD; however, the optimal acquisition protocols, diagnostic patterns and the utility of quantitation are controversial. This prospective study was conducted to demonstrate the higher predictive value of an additional late blood pool image to the three-phase bone scan compared to the regular three-phase bone scans in RSD patients associated with hemiplegia. Thirty-four RSD patients were enrolled into the study. Bone scans according to the new protocol were obtained for all patients. Those patients with either negative or positive bone scans with no evidence of RSD were followed for 6 months. The patients had positive bone scan findings and were symptomatic at the time of the study. Of these, seven patients (58.3%) subsequently became symptomatic and five patients (41.7%) remained asymptomatic at 6 months. None of the patients with negative bone scans had symptoms of RSD on presentation except one case. We conclude that the addition of a late blood pool image increases the predictive value and has an impact on initiating early treatment in asymptomatic patients.

Lymphoscintigraphic drainage patterns of the auricle in healthy subjects

BACKGROUND

In lymphoscintigraphies of the head and neck, multiple injections around a tumor result in variable drainage to multiple nodal basins. We undertook this study in healthy subjects to test whether single injections at specified points in the auricle display single predictable pathways and predict visualization of parotid sentinel lymph nodes (SLNs).

METHODS

Twenty-five healthy subjects were classified according to their injection points in the auricle. Each was injected bilaterally with 99mTc nanocolloid. Parotid and extraparotid lymph nodes were topographically differentiated. The procedure was repeated 1 week later.

RESULTS

Lymphoscintigraphy was reproducible. Each injection revealed a single SLN. Injection site predicted parotid SLN visualization. Two lymphatic territories with parotid or extraparotid drainage were identified.

CONCLUSIONS

Lymphatic territories in the auricle coincide with the vascular territories and branchial origins. Our findings contradict the notion that lymphatic drainage of the head and neck is unpredictable and variably involves multiple nodal basins.

Detection of alveolar epithelial injury by99mTc-DTPA radioaerosol inhalation lung scan following blunt chest trauma

DTPA clearance rate is a reliable index of alveolar epithelial permeability, and is a highly sensitive marker of pulmonary epithelial damage, even of mild degree. In this study, 99mTc-DTPA aerosol inhalation scintigraphy was used to assesss the pulmonary epithelial membrane permeability and to investigate the possible application of this permeability value as an indicator of early alveolar or interstitial changes in patients with blunt chest trauma. A total of 26 patients was chest trauma (4 female, 22 male, 31-80 yrs, mean age; 53+/-13 yrs) who were referred to the emergency department in our hospital participated in this tsudy. Technetium-99m diethylene triamine pentaacetic acid (DTPA) aerosol inhalation scintigraphy was performed on the first and thirtieth days after trauma. Clearance half times (T1/2) were calculated by placing a mono-exponential fit on the curves. Penetration index (PI) was calculated on the first-minute image. On the first day, mean T1/2 value of the whole lung was 63+/-19 minutes (min), and thirtieth day mean T1/2 value was 67+/-21 min. On the first day, mean PI values of the lung and 30th day mean PI value were 0.60+/-0.05, and 0.63+/-0.05, respectively. Significant changes were observed in radioaerosol clearance and penetration indices. Following chest trauma, clearance of 99mTc-DTPA increased owing to breakdown of the alveolar-capillary barrier. This increase in the epithelial permeability of the lung appears to be an early manifestation of lung disease that may lead to efficient therapy in the early phase.

The value and throughput of rest Thallium-201/stress Technetium -99m sestamibi dual-isotope myocardial SPECT

Myocardial perfusion scintigraphy is an established method in cardiology for the diagnosis and evaluation of coronary artery disease (CAD). Thallium-201 and Tc-99m sestamibi myocardial perfusion imaging has been widely accepted as non-invasive diagnostic procedure for detection of CAD, risk stratification and myocardial viability assessment. But, standard Tl-201 redistribution and same day or 2-day rest/stress Tc-99m sestamibi protocols are time-consuming. Hence, the dual isotope rest thallium-201/stress technetium-99m sestamibi gated single-photon emission tomography protocol has gained increasing popularity for these applications. Combining the use of thallium-201 with technetium-99m agents permits optimal image resolution and simultaneous assessment of viability. Dual-isotope imaging may be separate or simultaneous acquisition set-up. The more rapid completion of these studies is appreciated as an advantage by patients, technologists, interpreting and referring physicians, nurses and hospital management. Simultaneous imaging has the potential advantages of precise pixel registration and artifacts, if present, are identical in both thallium and sestamibi, and require only one set of imaging. Also, there are some disadvantages of spillover of activity from the Tc-99m to the Tl-201 window. Fortunately, despite this problem it can be overcome. Separate acquisition dual isotope also has some disadvantages. Difference in defect resolution in attenuation and scatter between T-201 and Tc-99m sestamibi potentially results in interpretation problems. But, studies about cost-effectiveness of dual isotope imaging showed that some selective elimination of the rest studies may decrease the cost of the nuclear procedures and should be considered in the current care health system.

Indium-111 octreotide scintigraphy in patients with bone tumours of the extremities

Radiolabelled somatostatin analogues are of potential value in the imaging of somatostatin receptor-positive tumours. Recently, somatostatin receptors have been demonstrated in the osteoblast precursor cells. In this preliminary study, we evaluated the uptake characteristics of indium-111 octreotide in two benign and two malignant bone tumours. Tracer accumulation was observed in all four cases, and overall lesion to background ratio (mean+/-SD) was 2. 74+/-0.84 and 2.98+/-1.49 at 4 h and 24 h, respectively. There was no clear relationship between 111In-octreotide accumulation and the benign or malignant nature of the tumour. In one patient, tracer uptake was inhibited by unlabelled octreotide administration. These results suggest that 111In-octreotide can be taken up by benign and malignant bone tumours. The inhibition of tumour uptake by treatment with cold octreotide supports the concept that specific uptake mechanisms are responsible for 111In-octreotide deposition by bone tumours.