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1.
Biochem Biophys Res Commun ; 714: 149940, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38677008

ABSTRACT

Orthostatic hypotension (OH) is a common condition. Many potential etiologies of OH have been identified, but in clinical practice the underlying cause of OH is often unknown. In the present study, we identified a novel and extraordinary etiology of OH. We describe a first case of acquired severe OH with syncope, and the female patient had extremely low levels of catecholamines and serotonin in plasma, urine and cerebrospinal fluid (CSF). Her clinical and biochemical evidence showed a deficiency of the enzyme aromatic l-amino acid decarboxylase (AADC), which converts l-DOPA to dopamine, and 5-hydroxytryptophan to serotonin, respectively. The consequence of pharmacologic stimulation of catecholaminergic nerves and radionuclide examination revealed her catecholaminergic nerves denervation. Moreover, we found that the patient's serum showed presence of autoantibodies against AADC, and that isolated peripheral blood mononuclear cells (PBMCs) from the patient showed cytokine-induced toxicity against AADC. These observations suggest that her autoimmunity against AADC is highly likely to cause toxicity to adrenal medulla and catecholaminergic nerves which contain AADC, resulting in hypocatecholaminemia and severe OH. Administration of vitamin B6, an essential cofactor of AADC, enhanced her residual AADC activity and drastically improved her symptoms. Our data thus provide a new insight into pathogenesis and pathophysiology of OH.


Subject(s)
Aromatic-L-Amino-Acid Decarboxylases , Autoimmunity , Hypotension, Orthostatic , Female , Humans , Middle Aged , Aromatic-L-Amino-Acid Decarboxylases/deficiency , Autoantibodies/blood , Autoantibodies/immunology , Catecholamines , Dopamine/metabolism , Hypotension, Orthostatic/etiology , Hypotension, Orthostatic/physiopathology , Serotonin/metabolism
2.
Eur J Nucl Med Mol Imaging ; 51(4): 1060-1069, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38008728

ABSTRACT

PURPOSE: To examine whether adherence to a low-iodine diet (LID) enhances the therapeutic efficacy of radioiodine therapy (RAI) in Graves' hyperthyroidism (GH) in iodine-rich areas. METHODS: We retrospectively evaluated 185 patients with GH from Aichi (n = 114) and Hokkaido (n = 71) Prefectures. Patients aged ≥ 18 years with GH who underwent RAI between December 2012 and March 2022 were divided into subgroups based on pretreatment with anti-thyroid drug (ATD) or potassium iodide (KI). Patients were followed up with LID from 18 days (group A) or 7 days (group H) before RAI to 3 days after RAI. The dose of radioactive iodine 131 (131I) was adjusted to deliver > 100 Gy to the thyroid. The associations between urinary iodine concentration on UIC2 vs. 24hRU and UIC2 vs. the 1-year RAI success rate (SR) were investigated. RESULTS: Compared with UIC1, UIC2 was significantly decreased in all subgroups (P < 0.01). An inverse correlation between UIC2 and 24hRU was observed in the four groups; however, the difference was insignificant. The SR in groups A and H was 85% and 89%, respectively. Univariate analysis revealed no association between UIC2 and SR in each group. Additionally, stratification of the 185 patients into quartiles using UIC2 yielded no significant differences in SR (p = 0.79). CONCLUSIONS: LID sufficiently reduced UIC in patients undergoing RAI. Although a lower UIC2 may increase 24hRU, it did not increase the success of RAI. The benefit of LID in enhancing the efficacy of RAI in GH treatment remains uncertain.


Subject(s)
Graves Disease , Hyperthyroidism , Iodine , Thyroid Neoplasms , Humans , Iodine Radioisotopes/adverse effects , Iodine/therapeutic use , Retrospective Studies , Thyroid Neoplasms/drug therapy , Graves Disease/radiotherapy , Graves Disease/drug therapy , Diet , Potassium , Treatment Outcome
3.
Neurosurg Rev ; 45(3): 2471-2480, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35319072

ABSTRACT

The purpose of this study was to examine the effects of combined revascularization for ischaemic-onset moyamoya disease (MMD) on cerebral haemodynamics by comparing cerebral blood flow (CBF) during the postoperative chronic phase with preoperative CBF. A retrospective cohort of 24 MMD patients (representing 31 surgeries) who received single photon emission computed tomography (SPECT) before and more than 6 months after surgery was investigated. The CBF value of each vascular territory was extracted from SPECT data, and the value relative to the ipsilateral cerebellar value (relative CBF, or RCBF) was calculated. The correlation between the revascularization effect and the proportional change in RCBF before and after surgery (calculated as post-RCBF/pre-RCBF ("post/pre-RCBF")) was analysed. Furthermore, the relationships between changes in neurological symptoms and post/pre-RCBF were investigated. Preoperative and postoperative mean RCBF values were 0.92 ± 0.15 and 0.96 ± 0.13 (p = 0.619) in the anterior cerebral artery territory, 0.99 ± 0.17 and 1.01 ± 0.17 (p = 0.598) in the middle cerebral artery territory and 1.15 ± 0.22 and 1.14 ± 0.19 (p = 0.062) in the posterior cerebral artery territory, respectively. No significant correlation was found between the revascularization score and post/pre-RCBF. The revascularization score and post/pre-RCBF were not significant predictors of worsening neurological symptoms postoperatively. No significant change in RCBF was observed in any vascular territory in the chronic phase after revascularization. Combined revascularization may assist in the redirection of blood flow from the internal to the external carotid system and contribute to CBF maintenance.


Subject(s)
Cerebral Revascularization , Moyamoya Disease , Cerebral Revascularization/methods , Cerebrovascular Circulation/physiology , Humans , Moyamoya Disease/surgery , Retrospective Studies , Tomography, Emission-Computed, Single-Photon
4.
J Appl Clin Med Phys ; 23(7): e13626, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35536775

ABSTRACT

PURPOSE: Accurate tracer accumulation evaluation is difficult owing to the partial volume effect (PVE). We proposed a novel semi-quantitative approach for measuring the accumulation amount by examining the approximate image. Using a striatal phantom, we verified the validity of a newly proposed method to accurately evaluate the tracer accumulations in the caudate and putamen separately. Moreover, we compared the proposed method with the conventional methods. METHODS: The left and right caudate/putamen regions and the whole brain region as background were identified in computed tomography (CT) images obtained by single-photon emission computed tomography (SPECT)/CT and acquired the positional information of each region. SPECT-like images were generated by assigning assumed accumulation amounts to each region. The SPECT-like image, approximated to the actual measured SPECT image, was examined by changing the assumed accumulation amounts assigned to each region. When the generated SPECT-like image most approximated the actual measured SPECT image, the accumulation amounts assumed were determined as the accumulation amounts in each region. We evaluated the correlation between the count density calculated by the proposed method and the actual count density of the 123 I solution filled in the phantom. Conventional methods (CT-guide method, geometric transfer matrix [GTM] method, region-based voxel-wise [RBV] method, and Southampton method) were also evaluated. The significance of differences between the correlation coefficients of various methods (except the Southampton method) was evaluated. RESULTS: The correlation coefficients between the actual count density and the SPECT count densities were 0.997, 0.973, 0.951, 0.950, and 0.996 for the proposed method, CT-guide method, GTM method, RBV method, and Southampton method, respectively. The correlation of the proposed method was significantly higher than those of the other methods. CONCLUSIONS: The proposed method could calculate accurate accumulation amounts in the caudate and putamen separately, considering the PVE.


Subject(s)
Dopamine Plasma Membrane Transport Proteins , Tomography, Emission-Computed, Single-Photon , Brain , Dopamine Plasma Membrane Transport Proteins/metabolism , Humans , Phantoms, Imaging , Tomography, Emission-Computed, Single-Photon/methods
5.
J Appl Clin Med Phys ; 22(4): 15-25, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33779118

ABSTRACT

PURPOSE: This study examined the variation in the thyroid volume determined by the ellipsoid approximation method due to differences in the measured length or area of the cross-sectional plane of CT images. METHODS: Forty-five patients with Graves' disease were included in this retrospective study. We designated the three-dimensional thyroid volumes extracted manually (VCT ) as the reference data and calculated five approximate volumes for comparison: (a) the mean volume of 8100 different thyroid volumes depending on the diameter of the cross-sectional plane at the midpoint of the major axis, (Vellipsoid,mean ); (b) the volume using the maximum diameter and its orthogonal diameter, (Vellipsoid,maxlength ); (c) the maximum (Vellipsoid,maxvolume ); (d) minimum (Vellipsoid,minvolume ) of the 8100 thyroid volumes; and (e) the volume determined with an equivalent circle diameter, (Vellipsoid,Heywood ). RESULTS: Thyroid volumes obtained via the ellipsoid approximation method varied depending on the diameter of the cross-sectional plane and included a mean error of approximately 20%, while the concordance correlation coefficient (CCC) differed for each approximate volume. Among these volumes, Vellipsoid,mean and Vellipsoid,Heywood were in good agreement with VCT , according to single regression analyses and the resultant CCC values, with mean errors of 0.1% and 10.4%, respectively. CONCLUSION: While Vellipsoid,Heywood approximated thyroid volumes with vastly reduced errors, we recommend utilizing three-dimensional thyroid volumetry if measurement accuracy is required.


Subject(s)
Thyroid Gland , Tomography, X-Ray Computed , Cross-Sectional Studies , Humans , Retrospective Studies , Thyroid Gland/diagnostic imaging
6.
J Comput Assist Tomogr ; 44(4): 578-585, 2020.
Article in English | MEDLINE | ID: mdl-32649425

ABSTRACT

OBJECTIVE: The objective of this study was to assess the correlation between dual-energy computed tomography quantitative parameters and hemodynamics in patients with chronic thromboembolic pulmonary hypertension. METHODS: Dual-energy computed tomography of 52 chronic thromboembolic pulmonary hypertension patients were evaluated retrospectively. The mean lung perfused blood volume (lung PBV) and the mean pulmonary artery (PA) enhancement measured at pulmonary parenchymal phase were compared with the hemodynamics by Spearman rank correlation coefficient (rs) and receiver operating characteristic analysis. RESULTS: Lung PBV was correlated with mean pulmonary arterial pressure (rs = 0.47, P < 0.001). Pulmonary artery enhancement was correlated with cardiac index (rs = -0.49, P < 0.001) and pulmonary vascular resistance (rs = 0.48, P < 0.001). The areas under the curves were 0.86 for lung PBV to predict mean pulmonary arterial pressure of >50 mm Hg and 0.86 for PA enhancement to predict pulmonary vascular resistance of >1000 dyne·s/cm. CONCLUSIONS: Lung PBV and PA enhancement could be indicators of hemodynamics.


Subject(s)
Hypertension, Pulmonary/diagnostic imaging , Pulmonary Embolism/diagnostic imaging , Radiography, Dual-Energy Scanned Projection/methods , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Area Under Curve , Blood Volume , Female , Humans , Hypertension, Pulmonary/physiopathology , Male , Middle Aged , Pulmonary Embolism/physiopathology , Radiographic Image Interpretation, Computer-Assisted , Retrospective Studies , Sensitivity and Specificity , Severity of Illness Index , Young Adult
7.
J Nucl Cardiol ; 26(1): 288-297, 2019 02.
Article in English | MEDLINE | ID: mdl-28432673

ABSTRACT

BACKGROUND: This study aimed to investigate whether indices of left ventricular (LV) dyssynchrony by gated myocardial perfusion SPECT (GMPS) could be useful to predict prognosis in chronic kidney disease (CKD) patients with normal perfusion defect scores. METHODS: One hundred and sixty-seven CKD patients with normal perfusion defect scores on adenosine-stress 201Tl GMPS and no previous history of overt heart diseases were enrolled. Phase standard deviation (PSD) and bandwidth (BW) were automatically calculated from GMPS. The major adverse cardiac events (MACEs) for a mean of 560 days were defined as sudden cardiac death, fatal arrhythmias, and acute coronary syndrome requiring urgent coronary revascularization. Patients were divided into two groups according to the presence or absence of MACEs. RESULTS: The MACEs occurred in 12 patients (7.1%). Patients who experienced MACEs showed significantly higher PSD and wider BW than those who did not. In the Kaplan-Meier event-free survival analysis, cardiac event rate was significantly higher in the high-PSD and wide-BW group (n = 81) than in the low-PSD and narrow-BW group (n = 71) (P = .002). The multivariate regression analysis revealed that the PSD was associated with MACEs (odds ratio 1.33, 95% confidence interval 1.05-1.69, P = .01). CONCLUSION: The LV dyssynchrony indices from GMPS may be novel prognostic predictors in CKD patients with normal perfusion defect scores.


Subject(s)
Kidney Failure, Chronic/diagnostic imaging , Myocardial Perfusion Imaging , Tomography, Emission-Computed, Single-Photon , Ventricular Dysfunction, Left/diagnostic imaging , Aged , Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography , Female , Heart Ventricles/diagnostic imaging , Humans , Male , Middle Aged , Prognosis , Retrospective Studies , Thallium Radioisotopes , Treatment Outcome
8.
J Nucl Cardiol ; 25(5): 1677-1687, 2018 10.
Article in English | MEDLINE | ID: mdl-28176257

ABSTRACT

BACKGROUND: The prognostic impact and pathophysiology of global left ventricular mechanical dyssynchrony (LVMD), namely mechanical dyssynchrony of whole left ventricle, as assessed by phase analysis of electrocardiographically gated (ECG-gated) myocardial perfusion SPECT has not been clearly elucidated in patients with dilated cardiomyopathy (DCM) and narrow QRS complex (<120 ms). METHODS AND RESULTS: Forty-six patients with DCM underwent ECG-gated myocardial 99mTc-sestamibi perfusion SPECT and endomyocardial biopsy. LV phase entropy was automatically calculated using a phase analysis of ECG-gated myocardial perfusion SPECT. The patients were divided into two groups according to the median phase entropy value: low-phase entropy (<0.61) (N = 23: LE group) and high-phase entropy (≥0.61) (N = 23: HE group). In the Kaplan-Meier survival analysis, the event-free survival rate was significantly lower in the HE group (log-rank P = 0.015). Moreover, high-phase entropy was an independent predictor of adverse cardiac events (hazard ratio, 5.77%; 95% confidence interval, 1.02-108.32; P = 0.047). Interestingly, the mRNA expression levels of sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) in endomyocardial biopsy specimens were significantly lower in the HE group (P = 0.015). CONCLUSION: LV phase entropy, which may reflect impairment of Ca2+ handling caused by decreased SERCA2a mRNA levels, is a novel prognostic predictor in patients with DCM and narrow QRS complex.


Subject(s)
Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography/methods , Cardiomyopathy, Dilated/diagnostic imaging , Electrocardiography , Entropy , Heart Ventricles/physiopathology , Myocardial Perfusion Imaging/methods , Calcium/metabolism , Cardiomyopathy, Dilated/physiopathology , Humans , Prognosis , Sarcoplasmic Reticulum Calcium-Transporting ATPases/genetics
9.
Gan To Kagaku Ryoho ; 45(11): 1619-1623, 2018 Nov.
Article in Japanese | MEDLINE | ID: mdl-30449850

ABSTRACT

We investigated the incidence of cholinergic symptoms related to irinotecan hydrochloride(CPT-11)and examined their association with clinical factors. The subjects were 61 patients with colorectal cancer for whom combination chemotherapy with CPT-11 was indicated between May 2008 and December 2014. The incidence of CPT-11-related cholinergic symptoms was investigated. Cholinergic symptoms were observed in 46 patients(75.4%), of whom 29(47.5%)showed Grade 2 or higher symptoms as follows: nasal discharge(47.5%), lacrimation(39.3%), nausea/vomiting(29.5%), and watery stool (26.2%). The results of the multivariate analysis showed that high-dose CPT-11 administration(150mg/m2)was a significant risk factor for the appearance of cholinergic symptoms and that PS 0 was a significant factor for reducing the onset of symptoms. It is important to adequately manage cholinergic symptoms, considering these clinical factors.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cholinergic Neurons/drug effects , Colorectal Neoplasms/drug therapy , Irinotecan/adverse effects , Adult , Aged , Aged, 80 and over , Female , Humans , Irinotecan/administration & dosage , Male , Middle Aged , Surveys and Questionnaires , Young Adult
10.
World J Surg ; 41(7): 1828-1833, 2017 07.
Article in English | MEDLINE | ID: mdl-28265732

ABSTRACT

BACKGROUND: We investigated the role of 18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) in predicting the effect of induction therapy in patients with thymic epithelial tumors. METHODS: Fourteen patients with thymic epithelial tumors who underwent PET-CT before and after induction therapy were retrospectively analyzed. The relationship between the change in the maximum standardized uptake value (SUVmax) in PET-CT, the response evaluation criteria in solid tumors and the pathologic response (Ef0, no necrosis of tumor cells; Ef1, some necrosis of tumor cells with more than one-third of viable tumor cells; Ef2, less than one-third of tumor cells were viable; and Ef3, no tumor cells were viable) was analyzed. RESULTS: The study cohort consisted of 5 males and 9 females. Nine of the patients had thymoma, and 5 had thymic carcinoma. The induction therapy included chemotherapy in 9 cases, chemoradiation therapy in 4 cases and radiation therapy in 1 case. Among the 8 patients with a pathologic response of Ef0/1, 5 were clinically evaluated as having stable disease (SD), while 3 were found to have had a partial response (PR). The SUVmax was elevated in 2 cases, unchanged in 1 and decreased in 5. On the other hand, 3 of the 6 patients with a pathologic response of Ef2, 3 were classified as having SD, while the other 3 had a PR. The SUVmax decreased in all of the patients. CONCLUSIONS: In comparison with CT, PET-CT seems to be useful for predicting the pathologic response to induction therapy in patients with thymic epithelial tumors.


Subject(s)
Neoplasms, Glandular and Epithelial/therapy , Positron Emission Tomography Computed Tomography/methods , Thymus Neoplasms/therapy , Adult , Aged , Female , Fluorodeoxyglucose F18 , Humans , Male , Middle Aged , Neoadjuvant Therapy , Neoplasms, Glandular and Epithelial/diagnostic imaging , Neoplasms, Glandular and Epithelial/pathology , Retrospective Studies , Thymoma/therapy , Thymus Neoplasms/diagnostic imaging , Thymus Neoplasms/pathology
11.
Tohoku J Exp Med ; 243(4): 289-295, 2017 12.
Article in English | MEDLINE | ID: mdl-29249732

ABSTRACT

Histological chorioamnionitis (CAM) is one form of intrauterine inflammation that is often seen in cases of preterm birth and are usually confirmed based on pathological examination after delivery. Histological CAM is related to significant neonatal morbidity and mortality; however, its etiology is unknown. The objective of this study was to determine the risk factors for histological CAM, using medical background, including fetal heart rate (FHR) patterns in preterm birth cases. The preterm birth cases delivered between 28 and 36 weeks were categorized into two groups according to the presence of histological CAM. Ninety-five preterm infants were included: 48 infants without histological CAM and 47 cases with histological CAM. The odds ratio for histological CAM was adjusted for FHR patterns, gestational age, and delivery mode (vaginal delivery or Caesarean section). Logistic regression analysis showed that vaginal delivery and gestational age were associated with histological CAM (odds Ratio [OR]: 3.1, 95% confidence interval [CI]: 1.0-9.4, p < 0.05, and OR: 0.8, 95% CI: 0.6-0.9, p < 0.05, respectively). However, there were no specific FHR patterns associated with histological CAM. Our study indicates that in preterm birth cases, histological CAM is not related to any specific FHR pattern. However, labor uterine contraction and immature gestational age at the delivery are related to histological CAM. These results may provide better delivery management methods for preterm birth cases.


Subject(s)
Chorioamnionitis/pathology , Heart Rate, Fetal/physiology , Premature Birth/etiology , Adult , Case-Control Studies , Delivery, Obstetric , Female , Humans , Infant, Newborn , Infant, Premature/physiology , Logistic Models , Pregnancy , Risk Factors
12.
Kaku Igaku ; 54(1): 603-621, 2017.
Article in Japanese | MEDLINE | ID: mdl-28804117

ABSTRACT

Internal radiation therapy using radium (223Ra) chloride injection (223Ra injection) is already being applied in actual clinical practice, however the NHI medical technical fee for the use of 223Ra injection has not yet been set. The Japanese Society of Nuclear Medicine surveyed health resource use for internal radiation therapy using 223Ra via questionnaires sent to medical institutions that have used 223Ra injection. Results showed that the necessary cost per patient is 1,005,567 JPY, based on the Draft Proposal for Medical Examination Value (Ver. 7.1) of the Japanese Health Insurance Federation for Surgery. 223Ra injection is supposed to be administered 6 times to each patient at 4-week intervals, and the fee per treatment was calculated to be 167,595 JPY. The appropriate NHI medical technical fee is thus considered to be 16,759 points per patient per treatment, which can be claimed 6 times per patient.


Subject(s)
Brachytherapy , Radium , Health Resources , Humans , Surveys and Questionnaires
13.
Gan To Kagaku Ryoho ; 42(11): 1379-83, 2015 Nov.
Article in Japanese | MEDLINE | ID: mdl-26602395

ABSTRACT

In this study, we investigated the clinical factors associated with acute kidney injury (AKI) due to combination therapy with cisplatin (CDDP) for treating lung cancer. We classified cases according to the presence or absence of adequate hydration and magnesium(Mg)administered above the regulations of the registered regimen to evaluate the effect due to differences in hydration on AKI. We also investigated clinical factors before and after administration of CDDP in each case group, and examined their association with AKI. Seventy-four patients with lung cancer that were indicated for treatment with a CDDP combination regimen between December 2012 and April 2013 were studied. The patients whose conditions progressed to AKI of Bgrade 2 accounted for 0% (0/33) in the Mg administration group and 7.3%(3/41)in the Mg non-administration group. In particular, 2 cases of serious AKI (grade 4) were observed in the Mg non-administration without additional hydration group. When compared with other groups, a high antiemetic rate and favorable urine volume were observed in the Mg administration with additional hydration group. In the patients with AKI, many developed hyponatremia of Bgrade 3 within 1 week after administration of CDDP. Although Mg administration and ample hydration seem to be effective measures to deal with CDDP-caused AKI, comprehensive monitoring, including antiemesis therapy, after CDDP administration and correction of electrolytes is important.


Subject(s)
Acute Kidney Injury/chemically induced , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cisplatin/adverse effects , Lung Neoplasms/drug therapy , Aged , Cisplatin/administration & dosage , Female , Humans , Male , Middle Aged , Osmotic Pressure , Retrospective Studies
14.
Ann Surg Oncol ; 21(6): 1801-8, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24531702

ABSTRACT

BACKGROUND: The purpose of this study was to assess the value of magnetic resonance imaging (MRI) and additional (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) for tumor response to neoadjuvant chemotherapy (NAC) in patients with locally advanced rectal cancer (LARC). METHODS: Data on 40 patients with LARC, who were treated with NAC and underwent MRI and FDG-PET/CT before and after NAC, were analyzed retrospectively. Surgery was performed at a median of 6 weeks after NAC and the images were compared with the histological findings. The tumor regression grade 3/4 was classified as a responder. RESULTS: Sixteen patients were pathological responders. Receiver operating characteristic (ROC) analysis revealed that MRI total volume after NAC (MRI-TV2) and ΔMRI-TV had the highest performance to assess responders (area under the ROC curve [AUC] 0.849 and AUC 0.853, respectively). The reduction rate of the maximum standardized uptake value (ΔSUVmax) was also an informative factor (AUC 0.719). There seems no added value of adding FDG-PET/CT to MRI-TV2 and ΔMRI-TV in assessment of NAC responders judging from changes in AUC (AUC of ΔSUVmax and MRI-TV2 was 0.844, and AUC of ΔSUVmax and ΔMRI-TV was 0.846). CONCLUSIONS: MRI-TV2 and ΔMRI-TV were the most accurate factors to assess pathological response to NAC. Although ΔSUVmax by itself was also informative, the addition of FDG-PET/CT to MRI did not improve performance. Patients with LARC who were treated by induction chemotherapy should receive an MRI examination before and after NAC to assess treatment response. A more than 70 % volume reduction shown by MRI volumetry may justify the omission of subsequent radiotherapy.


Subject(s)
Magnetic Resonance Imaging , Positron-Emission Tomography , Rectal Neoplasms/drug therapy , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Area Under Curve , Capecitabine , Chemotherapy, Adjuvant , Deoxycytidine/analogs & derivatives , Deoxycytidine/therapeutic use , Female , Fluorodeoxyglucose F18 , Fluorouracil/analogs & derivatives , Fluorouracil/therapeutic use , Humans , Leucovorin/therapeutic use , Male , Middle Aged , Neoadjuvant Therapy , Organoplatinum Compounds/therapeutic use , Oxaloacetates , ROC Curve , Radiopharmaceuticals , Rectal Neoplasms/diagnostic imaging , Rectal Neoplasms/pathology , Rectal Neoplasms/surgery , Retrospective Studies , Treatment Outcome
15.
Eur J Nucl Med Mol Imaging ; 41(12): 2232-41, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25104209

ABSTRACT

PURPOSE: We conducted a pilot study to prospectively evaluate the efficacy of PET/CT with (11)C-choline (choline PET/CT) for primary diagnosis and staging of urothelial carcinoma of the upper urinary tract (UUT-UC). METHODS: Enrolled in this study were 16 patients (9 men, 7 women; age range 51 - 83 years, mean ± SD 69 ± 10.8 years) with suspected UUT-UC. The patients were examined by choline PET/CT, and 13 underwent laparoscopic nephroureterectomy and partial cystectomy. Lymphadenectomy and chemotherapy were also performed as necessary in some of the patients. Of the 16 patients, 12 were confirmed to have UUT-UC (7 renal pelvis carcinoma and 5 ureteral carcinoma), 1 had malignant lymphoma (ureter), 1 had IgG4-related disease (ureter), and 2 had other benign diseases (ureter). RESULTS: Of the 16 study patients, 13 showed definite choline uptake in urothelial lesions, and of these, 11 had UUT-UC, 1 had malignant lymphoma, and 1 had IgG4-related disease. Three patients without choline uptake comprised one with UUT-UC and two with benign diseases. Of the 12 patients with UUT-UC, 3 had distant metastases, 2 had metastases only in the regional lymph nodes, and 7 had no metastases. Distant metastases and metastases in the regional lymph nodes showed definite choline uptake. The outcome in patients with UUT-UC, which was evaluated 592 - 1,530 days after surgery, corresponded to the patient classification based on the presence or absence of metastases and locoregional or distant metastases. Choline uptake determined as SUVmax 10 min after administration was significantly higher than at 20 min in metastatic tumours of UUT-UC (p < 0.05), whereas there was no statistically significant difference between the SUVmax values at 10 and those at 20 min in primary tumours of UUT-UC. CONCLUSION: This study suggests that choline PET/CT is a promising tool for the primary diagnosis and staging of UUT-UC.


Subject(s)
Carcinoma/diagnostic imaging , Choline , Positron-Emission Tomography , Radiopharmaceuticals , Urologic Neoplasms/diagnostic imaging , Adult , Aged , Aged, 80 and over , Carbon Radioisotopes , Carcinoma/pathology , Female , Humans , Male , Middle Aged , Multimodal Imaging , Pilot Projects , Predictive Value of Tests , Tomography, X-Ray Computed , Urologic Neoplasms/pathology
16.
Phys Med ; 119: 103298, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38309102

ABSTRACT

BACKGROUND: The dead-time loss reportedly degrades the accuracy of dosimetry using a gamma camera for targeted radionuclide therapy with Lu-177; therefore, the dead-time loss needs to be corrected. However, the correction is challenging. In this study, we propose a novel and simple method to shorten the apparent dead time rather than correcting it through experiments and Monte Carlo simulations. METHODS: An energy window of 208 keV ± 10 % is generally used for the imaging of Lu-177. Lower-energy gamma photons and X-rays of Lu-177 do not contribute to image formation but lead to dead-time losses. In our proposed method, a thin lead sheet was used to shield gamma photons and X-rays with energies lower than 208 keV, while detecting 208 keV gamma photons that penetrated the thin sheet. We measured and simulated the energy spectra and count rate characteristics of a clinical gamma camera system using a cylindrical phantom filled with a Lu-177 solution. Lead sheets of 1.0- and 0.5-mm thicknesses were used as thin shields, and the dead-time losses in tumour imaging with consumed Lu-177 were simulated. RESULTS: The apparent dead times with lead sheets of 1.0- and 0.5-mm thicknesses and without a lead sheet were 1.7, 1.9, and 5.8 µs for an energy window of 208 keV ± 10 %, respectively. The dead-time losses could be reduced from 10 % to 1.3 % using the 1.0-mm thick lead sheet in the simulated imaging of tumour. CONCLUSION: Our method is promising in clinical situations and studies on Lu-177 dosimetry for tumours.


Subject(s)
Neoplasms , Radioisotopes , Humans , Radioisotopes/therapeutic use , Gamma Cameras , Lutetium/therapeutic use , Phantoms, Imaging , Monte Carlo Method
17.
Ann Nucl Med ; 2024 May 24.
Article in English | MEDLINE | ID: mdl-38787504

ABSTRACT

OBJECTIVE: Radioiodine (I-131) therapy for hyperthyroidism is a well-established and safe treatment option. This study aimed to investigate the relationship between the computed tomography (CT) value and the function and volume of the thyroid gland by identifying the factors that induce changes in the CT value of patients with hyperthyroidism. METHODS: This retrospective study evaluated 38 patients with Graves' disease and 10 patients with Plummer disease. To obtain the mean CT value and volume of the thyroid gland, the entire thyroid gland was set as the region of interest. A test dose of 3.7 MBq I-131 was administered before initiating I-131 therapy, and the radioiodine uptake (RIU) rate was assessed after 3, 24, 96, and 168 h. An approximate curve was plotted based on the RIU values obtained, and the effective half-life (EHL) was calculated. The correlation between the mean CT value and the volume of the thyroid gland, 24-h RIU, EHL, and the free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), and TSH receptor antibody (TRAb) levels was evaluated. RESULTS: The CT value exhibited a significant positive correlation with EHL in patients with Graves' disease (r = 0.62, p < 0.0001) as well as patients with Plummer disease (r = 0.74, p < 0.05). However, it did not display any correlation with the remaining parameters. CONCLUSION: The CT value is significantly correlated with EHL, suggesting that it reflects thyroid function and is mainly related to the factors associated with iodine discharge.

18.
JACC Cardiovasc Imaging ; 17(1): 45-58, 2024 01.
Article in English | MEDLINE | ID: mdl-37452820

ABSTRACT

BACKGROUND: Fluorodeoxyglucose positron emission tomography (18F-FDG-PET) can noninvasively assess active inflammatory myocardium in patients with cardiac sarcoidosis (CS). Prednisolone (PSL) is the initial drug of choice for active CS; however, its efficacy has not been prospectively evaluated. Moreover, there are no alternative systematic treatment strategies. OBJECTIVES: The goal of this study was to evaluate the efficacy of methotrexate (MTX) in patients refractory to PSL assessed by using cardiac metabolic activity (CMA) in 18F-FDG-PET. METHODS: A total of 59 patients with active CS were prospectively enrolled. CMA (standardized uptake value × accumulation area) was used as an indicator of active inflammation, and a 6-month regimen of PSL therapy was introduced, followed by a second FDG scan. Poor responders to PSL therapy (CMA reduction rate <70%) and patients with recurrent CS (CMA reduction rate ≥70% after initial PSL therapy but CMA recurred after an additional 6 months of therapy) were randomly assigned to the MTX or repeat PSL (re-PSL) therapy groups for another 6 months. RESULTS: Fifty-six patients completed the initial 6-month PSL therapy regimen. Median CMA reduced from 203.3 to 1.0 (P < 0.001), and 47 patients were allocated to the response group, 9 to the poor response group, and 2 to the recurrent group. Accordingly, 11 patients were randomly assigned to the MTX (n = 5) or re-PSL (n = 6) groups. After 6 months, neither group showed a significant reduction in CMA values. MTX was comparable to re-PSL in reducing CMA. CONCLUSIONS: The 6-month regimen of PSL was a potent therapeutic tool for active CS. When MTX was added to low-dose PSL in patients refractory to the initial PSL therapy, there was no significant difference compared with re-PSL. Further studies are needed to evaluate the therapeutic potential of MTX for active CS, including how MTX works when it is administered in higher doses or for longer periods.


Subject(s)
Cardiomyopathies , Myocarditis , Sarcoidosis , Humans , Fluorodeoxyglucose F18 , Cardiomyopathies/diagnostic imaging , Cardiomyopathies/drug therapy , Radiopharmaceuticals , Predictive Value of Tests , Myocardium/metabolism , Sarcoidosis/diagnostic imaging , Sarcoidosis/drug therapy , Sarcoidosis/metabolism , Positron-Emission Tomography/methods , Immunosuppression Therapy
19.
Clin Neurol Neurosurg ; 236: 108110, 2024 01.
Article in English | MEDLINE | ID: mdl-38171051

ABSTRACT

OBJECTIVE: This study aimed to analyze whether the development of donor vessels after combined revascularization surgery for moyamoya disease (MMD) is related to cerebral blood flow (CBF) changes. METHODS: We retrospectively reviewed the charts of 11 adult (12 hemispheres) and 13 pediatric (19 hemispheres) patients who underwent combined revascularization in our department. The total vessel cross-sectional area (TVA) was the sum of the cross-sectional areas of the superficial temporal, middle meningeal, and deep temporal arteries imaged using time-of-flight magnetic resonance angiography. The ipsilateral relative CBF (RCBF) on the brain surface in the craniotomy area was calculated by single-photon emission computed tomography. ΔTVA and ΔRCBF were defined as the preoperative and postoperative ratios of TVA and RCBF, and their correlations were analyzed in adult and pediatric patients. RESULTS: The TVA and RCBF showed a significant increase after surgery, regardless of the age group. However, there was no significant correlation between ΔTVA and ΔRCBF in either the adult or pediatric groups. While the adult group exhibited significantly higher ΔRCBF values compared to the pediatric group (p < 0.01, r = -0.44), the ΔTVA values were higher in the pediatric group compared to the adult group (p = 0.06). CONCLUSIONS: In the chronic phase after combined revascularization surgery for MMD, the development of measurable TVA of donor vessels does not necessarily correlate with an increase in CBF around the craniotomy area.


Subject(s)
Cerebral Revascularization , Moyamoya Disease , Adult , Humans , Child , Moyamoya Disease/diagnostic imaging , Moyamoya Disease/surgery , Retrospective Studies , Brain/diagnostic imaging , Brain/surgery , Cerebrovascular Circulation/physiology
20.
Eur J Nucl Med Mol Imaging ; 40(2): 262-70, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23096078

ABSTRACT

PURPOSE: We investigated whether myocardial (123)I-metaiodobenzylguanidine ((123)I-MIBG) scintigraphy predicts impairment of myocardial functional reserve in response to dobutamine stress in patients with idiopathic dilated cardiomyopathy (DCM). METHODS: Forty DCM patients (LVEF 39 ± 12 %) underwent myocardial (123)I-MIBG scintigraphy, echocardiography, and cardiac catheterization. Myocardial (123)I-MIBG uptake was quantified as the delayed heart to mediastinum (H/M) ratio and washout rate (WR). Local denervation was evaluated on polar map images. LV dP/dt (max) and T(1/2) were determined from left ventricular pressure curves at baseline and during dobutamine infusion (15 µg/kg /min). Patients were classified into two groups as follows: group A comprised 21 patients showing a delayed H/M ratio of <1.9 (median value); group B comprised 19 patients showing a delayed H/M ratio of ≥ 1.9. RESULTS: The percentage change in heart rate (%HR), LV dP/dt (max) (%LV dP/dt (max)), and T (1/2) (%T (1/2)) from baseline to dobutamine stress were significantly more reduced in group A than in group B (39.3 ± 20.2 %, 55.2 ± 24.1 %, p < 0.01; 102.3 ± 46.3 %, 152.0 ± 72.3 %, p < 0.05; 38.7 ± 15.3 %, 46.9 ± 15.4 %, p < 0.05, respectively). No significant differences between the two groups were observed in the echocardiographic parameters or baseline cardiac catheterization parameters. Significant correlations were found between delayed H/M ratio and %HR (r = 0.35, p < 0.05), %LV dP/dt (max) (r = 0.45, p < 0.05) and %T (1/2) (r = 0.34, p < 0.05). Significant inverse correlations were also found between WR and %HR (r = -0.37, p < 0.05), %LV dP/dt (max) (r = -0.60, p < 0.0001), and %T (1/2) (r = -0.34, p < 0.05). SPECT images revealed enhanced denervation from the inferoposterior to anterior wall in accordance with the advancement of global denervation. CONCLUSION: Reduced (123)I-MIBG uptake and increased washout were related to impairment in adrenergic myocardial functional reserve in idiopathic DCM.


Subject(s)
Cardiomyopathy, Dilated/diagnostic imaging , Heart/diagnostic imaging , Iodine Radioisotopes/pharmacology , Myocardium/pathology , Radionuclide Imaging/methods , Adult , Cardiac Catheterization , Dobutamine/metabolism , Echocardiography/methods , Exercise Test , Female , Heart Rate , Heart Ventricles , Humans , Male , Mediastinum/pathology , Middle Aged , Myocardial Perfusion Imaging/methods , Myocardium/metabolism , Receptors, Adrenergic, beta/metabolism
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