I-123 Metaiodobenzylguanidine Research Articles

The Utility of Segmental Analysis in Cardiac I-123 MIBG SPECT in Parkinson's Disease.

Cardiac images using I-123 metaiodobenzylguanidine (MIBG) are widely used to evaluate cardiac sympathetic denervation in Parkinson's disease (PD). The aim of this study was to evaluate the utility of segmental analysis on cardiac MIBG SPECT in PD patients. In total, 36 patients with PD (n = 26) or essential tremor (ET, n = 10) who underwent MIBG cardiac SPECT were enrolled. The heart-to-mediastinum (H/M) ratios of MIBG uptake were acquired on planar images. For the segmental analysis of SPECT images, we evaluated the summed defect score (SDS) using a 17-segment model. The diagnostic abilities of H/M ratios and segmental parameters on MIBG SPECT were assessed by ROC curve analysis. The H/M ratios were significantly lower in PD than in ET patients (p < 0.05). On segmental analysis, SDS was significantly higher in PD patients than in the ET group (7.04 ± 4.09 vs. 2.90 ± 2.80; p = 0.006). The defect score of the anteroseptal region showed a significant difference between the groups (p = 0.002). The ROC analysis suggested only SDS (AUC = 0.785, p = 0.0003) and defect scores in the anteroseptal (AUC = 0.800, p < 0.0001) and inferior (AUC = 0.667, p = 0.013) regions showed significant diagnostic ability to differentiate PD from ET. Segmental parameters from cardiac MIBG SPECT images can provide additional information to differentiate PD from ET patients. Beyond H/M ratios from planar images, we recommend an MIBG SPECT study to evaluate sympathetic denervation in PD.

Usefulness of Cardiac Meta-Iodobenzylguanidine Imaging to Identify Patients With Chronic Heart Failure and Left Ventricular Ejection Fraction

Patients with chronic heart failure (CHF) at risk of sudden cardiac death (SCD) are often treated with implantable cardiac defibrillators (ICDs). However, current criteria for device use that is based largely on left ventricular ejection fraction (LVEF) lead to many patients receiving ICDs that never deliver therapy. It is of clinical significance to identify patients who do not require ICDs. Although cardiac I-123 meta-iodobenzylguanidine (MIBG) imaging provides prognostic information about CHF, whether it can identify patients with CHF who do not require an ICD remains unclear. We studied 81 patients with CHF and LVEF <35%, assessed by cardiac MIBG imaging at enrollment. The heart-to-mediastinal ratio (H/M) in delayed images and washout rates were divided into 6 grades from 0 to 5, according to the degree of deviation from control values. The study patients were classified into 3 groups: low (1 to 4), intermediate (5 to 7), and high (8 to 10), according to the MIBG scores defined as the sum of the H/M and washout rate scores. Sixteen patients died of SCD during a follow-up period. Patients with low MIBG score had a significantly lower risk ofSCD than those with intermediate and high scores (low [n= 19], 0%; intermediate [n=37], 19%; high [n= 25], 36%; p= 0.001). The positive predictive value of low MIBG score for identifying patients without SCD was 100%. In conclusion, the MIBG score can identify patients with CHF and LVEF <35% who have low risk of developing SCD.

Cardiocirculatory manifestations in Parkinson's disease patients without orthostatic hypotension.

The objective of this study was to characterize cardiac sympathetic denervation in Parkinson's disease (PD) patients without neurogenic orthostatic hypotension (NOH), both in terms of hemodynamics and in its relation with vascular denervation. We studied 20 PD patients without NOH. We analyzed the heart rate and blood pressure variability during various physical maneuvers. The following parameters were calculated: expiratory-inspiratory ratio, stroke volume, cardiac output, cardiac index, left ventricular ejection time, left ventricular work index, thoracic fluid content, total peripheral resistance and baroreflex sensitivity (BRS). We also measured direct and spectral derivatives of cardiac (cardiovagal) parasympathetic function. Myocardial I-123 metaiodobenzylguanidine (MIBG) scintigraphy was performed and early and late heart/mediastinum uptake ratios were analyzed. We observed that the late heart/mediastinum uptake ratio was 1.33±0.21. This parameter was correlated with years since diagnosis (correlation coefficient:-0.485; P=0.05), Unified Parkinson's Disease Rating Scale (UPDRS) III score (cc:-0.564; P=0.02) and pressure recovery time in the Valsalva maneuver (cc: 0.61; P<0.001). At rest, it was correlated with BRS (cc:0.75; P=0.003) and low-frequency diastolic blood pressure (LFDBP; cc: 0.58;P=0.017). We found no correlations with any of the cardiography impedance variables. In linear regression models, the variable that best correlated with MIBG results was LFDBP. Our results support that in absence of NOH the degree of denervation of the heart does not produce any effect on its inotropic function. Moreover, BRS and LFDBP can be used as an indirect measure of cardiac sympathetic denervation at rest.

術前内照射および化学療法が著効し,根治切除し得た巨大異所性褐色細胞腫の1例

A 46-year-old man was found to be positive for occult blood at a medical checkup and was revealed to have a 14-cm tumor on the right side of abdominal aorta by a subsequent abdominal CT scan. The endocrinology laboratory data showed elevations in the levels of serum noradrenaline, and ectopic pheochromocytoma was suspected. The tumor was compressing the inferior vena cava and portal vein, the superior mesenteric artery and the pancreas. Since it would be difficult to cure by operation, neoadjuvant therapy was started using radioisotope therapy by I-131 metaiodobenzylguanidine (131I-MIBG) and chemotherapy (CVD therapy ; cyclophosphamide, vincristine, dacarbazine). He was treated with three courses of radioisotope therapy and 16 courses of chemotherapy, which significantly reduced the tumor size. This made radical resection possible ; we were able to avoid the merger excision of great vessels and other organs. On pathological and immunopathological findings, the tumor was diagnosed as ectopic pheochromocytoma. Regarding the safety and curability of the treatment, neoadjuvant therapy may be useful in treating very large tumors that show invasion of other organs.

Experiences from Introducing Standardized High Dose 131I-mIBG Treatment of Children with Refractory Neuroblastoma: Differences in Effective Dose to Patients and Exposure to Caregivers

Aims: High dose 131I-meta iodobenzylguanidine (131I-mIBG) combined with radiosensitizing topotecan and peripheral blood stem cell support is a promising treatment regimen for children with neuroblastoma (NB). Here we present our first experiences, with particular focus on in vivo whole-body dosimetry and radiation exposure to family caregivers and hospital staff. Methods: Five children with relapsed or refractory NB were treated during 2012-2014. 131I-mIBG was administered in two fractions at two weeks apart, aiming for a total whole-body radiation-absorbed dose of 4 Gy. The 131I-mIBG activity for the 2nd administration was calculated on the basis of the measured whole-body dose following the 1st administration. Patients were isolated in a lead-shielded room, and all caregivers and staff received radiation safety training, and carried an electronic personal dosimeter. Results: The total administered activity ranged from 5.1 to 28.6 GBq (median: 22.9 GBq), resulting in effective whole-body doses ranging from 2.1 to 4.3 Gy (median: 3.8 Gy). Two out of five patients deviated from the anticipated dose exposure defined by the treatment protocol; one patient received 4.3 Gy after a single administration, and for one patient the total whole-body dose was lower than anticipated (2.1 Gy). Radiation dose to family caregivers ranged from 0.1 to 8.0 mSv. For staff members, the overall radiation dose was low, and provided no concern regarding personal dosimetry. Conclusion: High-dose 131I-mIBG treatment of children with NB has been successfully established at our institution. Radiation doses to caregivers and hospital staff are acceptable and in compliance with national and international guidelines. Two out of five patients deviated from the anticipated dose exposure, hence, accurate dosimetry-guidance during administration of high dose 131I-mIBG treatment is necessary.

Glow in the dark.

To highlight the importance of radiation safety and handling of radioactive secretions following 131I-meta iodobenzylguanidine (131I-mIBG) use in the treatment of neuroblastoma. We report a 4-year-old girl with stage 4 neuroblastoma, on whom's single-photon emission computer tomography (SPECT) scan we demonstrate four extra-corporal areas of radioactivity confirming radiation uptake in the four corners of her 'comfort blanket' that had been used to cover her during the scan. It transpired that she had been sucking on the four corners of this blanket. The patient's secretions remain radioactive for some time following scintigraphy, as evidence of radioactivity in the patient's comfort blanket. Radioactive uptake of 131I-mIBG in the salivary glands of patients has previously been reported. This illustrative case emphasizes that patient's secretions remain radioactive following treatment and highlights the importance of careful handling of radioactive secretions.

Abstract 12925: Combination of Cardiac I-123 Metaiodobenzylguanidine Imaging Findings and Early Repolarization Pattern Improve the Predictive Power of Sudden Cardiac Death in Patients With Chronic Heart Failure

Background: Identification of patients with chronic heart failure (CHF) at risk for sudden cardiac death (SCD) is an important objective. Cardiac I-123 metaiodobenzylguanidine (MIBG) imaging findings provide prognostic information in patients with CHF. On the other hand, early repolarization pattern (ERP) is associated with life-threatening arrhythmia events. Moreover, it has been shown that ERP would be associated with an increased risk of SCD in CHF patients. However, there is no information available on the long-term prognostic value of combining cardiac MIBG imaging findings and ERP for the prediction of SCD in CHF patients. Methods: We studied 92 CHF outpatients (NYHA class: 2.1±0.6) with LVEF &lt; 40% [30±7%) in our prospective cohort study. We performed MIBG scintigraphy, and measured the heart-to-mediastinum ratio on the delayed image (HMRd), of which the abnormal value was defined as &lt; 1.7. Furthermore, we obtained the standard 12-lead electrocardiogram at enrollment. ERP was defined as J-point elevation ≤ 0.1 mV in at least 2 inferior or lateral leads. Results: At enrollment, 41 patients had abnormal HMRd and 19 patients had ERP. During a follow-up period of 7.7±4.3 yrs, 22 patients died suddenly. A multivariate Cox analysis revealed that HMRd (p=0.001) and ERP (p=0.017) were significantly and independently associated with SCD. Kaplan-Meier analysis showed that SCD was significantly more frequently observed in patients with both abnormal HMRd and ERP and those with either abnormal HMRd or ERP than those with neither abnormal HMRd nor ERP (55% vs 33% vs 7%, respectively, p&lt;0.0001). The hazard ratio for SCD prediction in patients with both abnormal HMRd and ERP was 14.7 (95%CI 3.6 to 60.1), which was twofold of the hazard ratio in patients with either abnormal HMRd or ERP (HR 6.5 [95%CI 1.8 to 7.8]) Conclusion: The combination of cardiac MIBG imaging and ERP would provide the incremental prognostic information for the prediction of SCD in CHF patients.

Abstract 15912: Cardiac I-123 Metaiodobenzylguanidine Imaging Provides the Additional Prognostic Information to the Model for End-Staged Liver Disease in Patients With Chronic Heart Failure

Backgrounds: Liver dysfunction has a prognostic impact on the outcome of patients with advanced heart failure. A model of end-stage liver disease (MELD) is a robust scoring system of liver dysfunction, and a high score has been shown to be associated with poor prognosis in ambulatory patients with heart failure. In addition, cardiac metaiodobenzylguanidine (MIBG) imaging provides prognostic information in patients with chronic heart failure (CHF). However, the long-term predictive value of combining MELD score and cardiac MIBG imaging in CHF patients has not been elucidated. We sought to investigate whether cardiac MIBG imaging provides additional prognostic information to MELD score in CHF patients. Methods: We studied 109 CHF outpatients (NYHA class:2.1±0.6, ischemic origin:52%) with left ventricular ejection fraction27%) had a significantly greater risk of the cardiac events than did those with normal WR for both with high MELD score ([[Unable to Display Character: &amp;#61619;]]10) (70% [19/27] vs 31% [4/13], p=0.028, hazard ratio 4.0 [95%CI 1.2-13.6]) and low MELD score (&lt;10) (34%[10/29] vs 8%[3/40], p=0.005, hazard ratio 6.4 [95%CI 1.7-23.2]). Conclusion: Cardiac MIBG imaging would provide the additional prognostic information to MELD score for CHF patients.

Multicenter cross-calibration of I-123 metaiodobenzylguanidine heart-to-mediastinum ratios to overcome camera-collimator variations

BackgroundThe heart-to-mediastinum ratio (HMR) of 123I-metaiodobenzylguanidine (MIBG) showed variations among institutions and needs to be standardized among various scinticamera-collimator combinations. MethodsA total of 225 phantom experiments were performed in 84 institutions to calculate cross-calibration coefficients of HMR. Based on phantom studies, a conversion coefficient for each camera-collimator system was created, including low-energy (LE, n = 125) and a medium-energy (ME, n = 100) collimators. An average conversion coefficient from the most common ME group was used to calculate the standard HMR. In clinical MIBG studies (n = 52) from three institutions, HMRs were standardized from both LE- and ME-type collimators and classified into risk groups of <1.60, 1.60-2.19, and ≥2.20. ResultsThe average conversion coefficients from the individual camera-collimator condition to the mathematically calculated reference HMR ranged from 0.55 to 0.75 for LE groups and from 0.83 to 0.95 for ME groups. The conversion coefficient of 0.88 was used to unify HMRs from all acquisition conditions. Using the standardized HMR, clinical studies (n = 52) showed good agreement between LE and ME types regarding three risk groups (κ = 0.83, P < .0001, complete agreement in 90%, 42% of the patients reclassified into the same risk group). ConclusionBy using the reference HMR and conversion coefficients for the system, HMRs with various conditions can be converted to the standard HMRs in a range of normal to low HMRs.

Feasibility and advantage of adding (131)I-MIBG to (90)Y-DOTATOC for treatment of patients with advanced stage neuroendocrine tumors.

BackgroundPeptide receptor radionuclide therapy (PRRT) is an effective form of treatment for patients with metastatic neuroendocrine tumors (NETs). However, delivering sufficient radiation dose to the tumor to result in a high percentage of long-term tumor remissions remains challenging because of the limits imposed on administered activity levels by radiation damage to normal tissues. The goal of this study was to evaluate the dosimetric advantages of adding 131I meta-iodobenzylguanidine (131I-MIBG) to 90Y DOTA Phe1-Tyr3-octreotide (90Y-DOTATOC) in patients with advanced stage midgut NETs.MethodsTen patients were imaged simultaneously with 131I-MIBG and 111In-pentetreotide (as a surrogate for 90Y-DOTATOC) on days 1, 2, and 3 post-administration. Blood samples were obtained at the same time points. Using dosimetry measures from this data and our previously published methodology for calculating optimal combined administered activity levels for therapy, we determined the amount of 131I-MIBG that could be added to 90Y-DOTATOC without exceeding normal organ dose limits (marrow and kidneys) along with the expected increase in associated tumor dose, if any.ResultsWe found that a median value of 34.6 GBq of 131I-MIBG could be safely added to 90Y-DOTATOC (delivered over multiple cycles) by reducing the maximum total deliverable 90Y-DOTATOC by a median value of 24.5%. Taking this treatment approach, we found that there would be a median increase in deliverable tumor dose of 4,046 cGy in six of the ten subjects. Of note, there were a small number of metastases that were positive for only one or the other of these radiopharmaceuticals within the same subject.ConclusionsWe conclude that approximately half of the patients with midgut NETs that are eligible for PRRT could reasonably be expected to benefit from the addition of 131I-MIBG to 90Y-DOTATOC.

SCREENING IMPLANTABLE CARDIOVERTER DEFIBRILLATOR ELIGIBLE HEART FAILURE PATIENTS WITH I-123 METAIODOBENZYLGUANIDINE IMAGING VERSUS NO SCREENING: AN ECONOMIC MODEL COMPARING COSTS AND OUTCOMES

ADMIRE-HF/HFX prospectively validated I-123 Metaiodobenzylguanidine (mIBG) imaging in predicting prognosis of all-cause and cardiac mortality in NYHA II and III HF patients with LVEF≥ 35%. To assess the cost-effectiveness of mIBG for screening patients referred for an ICD, we developed a decision-

Effect of intramyocardial bone marrow-derived mononuclear cell injection on cardiac sympathetic innervation in patients with chronic myocardial ischemia

Intramyocardial bone marrow cell injection has been associated with improvements in myocardial perfusion and left ventricular function. The current substudy of a randomized, placebo-controlled, double-blinded study, investigated the effect of intramyocardial bone marrow cell injection on myocardial sympathetic innervation in patients with chronic myocardial ischemia. In a total of 16 patients (64 ± 8 years, 13 men), early and late iodine-123 metaiodobenzylguanidine (MIBG) imaging was performed before and 3 months after intramyocardial bone marrow cell injection. No improvements were observed in global early H/M ratio (P = 0.40), late H/M ratio (P = 0.43) and cardiac washout rate (P = 0.98). However, late 123-I MIBG SPECT defect score showed a trend to improvement in the bone marrow cell group (from 31.0 ± 7.1 to 28.1 ± 14.9) as compared to the placebo group (from 33.6 ± 8.5 to 34.5 ± 9.8, P = 0.055 between groups). This trend was mainly driven by a substantial improvement in three bone marrow cell-treated patients, which all had diabetes and severe MIBG defects. In these patients, the extent and severity of MIBG defects improved substantially independent of myocardial perfusion and cell injection sites. The present study does not demonstrate improvements in global cardiac sympathetic nerve innervation after intramyocardial bone marrow cell injection in patients with chronic myocardial ischemia. However, regional analysis of sympathetic nerve innervation reveals improvements in three diabetic patients independent of myocardial perfusion, suggestive of a therapeutic effect on diabetic cardiac sympathetic dysinnervation.

Adult neuroblastoma complicated by increased intracranial pressure: a case report and review of the literature.

Neuroblastoma is the third most commonly occurring malignancy of the pediatric population, although it is extremely rare in the adult population. In adults, neuroblastoma is often metastatic and portends an extremely poor overall survival. Our case report documents metastatic neuroblastoma occurring in a healthy 29-year-old woman whose course was complicated by an unusual presentation of elevated intracranial pressures. The patient was treated with systemic chemotherapy, I131 metaiodobenzylguanidine (MIBG) radiotherapy, and autologous stem cell transplant (SCT). Unfortunately the patient's response to therapy was limited and she subsequently died. We aim to review neuroblastoma in the context of increased intracranial pressure and the limited data of neuroblastoma occurring in the adult population, along with proposed treatment options.

A systematic review of 131I-meta iodobenzylguanidine molecular radiotherapy for neuroblastoma

The optimal use and effectiveness of 131I-meta iodobenzylguanidine (131I-mIBG) molecular radiotherapy for neuroblastoma remain unclear despite extensive clinical experience. This systematic review aimed to improve understanding of the current data and define uncertainties for future clinical trials. Bibliographic databases were searched for neuroblastoma and 131I-mIBG. Clinical trials and non-comparative case series of 131I-mIBG therapy for neuroblastoma were included. Two reviewers assessed papers for inclusion using the title and abstract with consensus achieved by discussion. Data were extracted by one reviewer and checked by a second. Studies with multiple publications were reported as a single study. The searches yielded 1216 citations, of which 51 publications reporting 30 studies met our inclusion criteria. No randomised controlled trials (RCTs) were identified. In two studies 131I-mIBG had been used as induction therapy and in one study it had been used as consolidation therapy. Twenty-seven studies for relapsed and refractory disease were identified. Publication dates ranged from 1987 to 2012. Total number of patients was 1121 with study sizes ranging from 10 to 164. There was a large amount of heterogeneity between the studies with regard to patient population, treatment schedule and response assessment. Study quality was highly variable. The objective tumour response rate reported in 25 studies ranged from 0% to 75%, mean 32%. We conclude that 131I-mIBG is an active treatment for neuroblastoma, but its place in the management of neuroblastoma remains unclear. Prospective randomised trials are essential to strengthen the evidence base.

Abstract 18464: Prognostic Value of Cardiac I-123 Metaiodobenzylguanidine Imaging in Patients With Chronic Heart Failure: A Prospective Comparative Study With Fragmented QRS Complexes

Backgrounds: Cardiac I-123 metaiodobenzylguanidine (MIBG) imaging provides prognostic information in patients with chronic heart failure (CHF). On the other hand, fragmented QRS complexes (fQRS) on the 12-lead ECG, which would be thought to reflect myocardial fibrosis, have been associated with poor outcome in CHF patients. However, there is no information available on the comparison of the prognostic values between MIBG imaging and fQRS in CHF patients. Methods: We studied 111 CHF outpatients with LVEF &lt;40% in our prospective cohort study. The cardiac MIBG heart-to-mediastinum ratio (H/M) and washout rate (WR) were calculated from the chest anterior view images obtained at 20 and 200 min after isotope injection. Abnormal WR was defined as &gt; 27%. fQRS was defined by the presence of &gt;2 notches on the R wave or the S wave and had to be present in &gt;or=2 contiguous inferior (II, III, aVF), lateral (I, aVL, V(6)) or anterior (V(1) to V(5)) leads. Results: During a follow up period of 7.8±4.4 yrs, 39 patients had cardiac death. At multivariate Cox analysis, WR (p=0.0002) and LVEF (p=0.0035) were significantly independently associated with cardiac death, while H/M at the delayed image (p=0.003) and fQRS (p=0.088) showed the association with cardiac death at univariate analysis. Patients with abnormal WR (&gt;27%) had a significantly higher risk of cardiac death than those with normal WR (55% (31/56) vs 15% (8/55), p&lt;0.0001, adjusted hazard ratio 4.1 (95%CI 1.8-9.7)), while there was a tendency of higher risk of cardiac death in patients with fQRS (63%(10/16) vs 31%(29/95), p=0.08, hazard ratio 1.9 (95%CI 0.9-3.9)). Conclusion: The cardiac MIBG imaging had more valuable prognostic value than fQRS in CHF patients.

Using systematic reviews to identify research gaps - a case study: mIBG for the treatment of neuroblastoma in children

Most childhood cancers are rare conditions, so research needs to be efficient. With only a limited number of children available for trials per year it seems sensible to use data from previous research. Systematic review methodology can do this whilst minimizing bias. Others also recommend undertaking a systematic review as part of a trial planning process in order to reduce unwanted duplication, help ensure that new research builds on lessons from earlier research and place the findings of the new research in proper context. [Clark M 2007] However, there are some who would question the value of undertaking systematic reviews when only less than optimally designed studies are available, which is particularly true in paediatric oncology where non-comparative studies dominate. Using a recently completed systematic review that investigated the effectiveness of 131I-meta iodobenzylguanidine (131I-mIBG) molecular radiotherapy for neuroblastoma, we aim to present some of the methodological challenges that we encountered during the review, such as study identification, quality assessment and salami publications. We will also discuss the presentation, analysis and interpretation of the results. We chose to perform quantitative analyses, which gave estimates of effect sizes, with measures of uncertainty, and evidence on dose/response relationships. We considered that such analyses gave greater insight into the data as a whole, while also being aware that quantitative analyses of generally poor quality data might be seen as providing a false sense of validity to sub-optimally designed studies.

Significance of I-123 metaiodobenzylguanidine (123I-MIBG) lung activity in subjects with heart failure in comparison to healthy control subjects

BackgroundLittle is known concerning the significance of lung activity of the sympathetic neuronal imaging agent 123I-MIBG in heart failure patients and healthy subjects. Methods123I-MIBG activity was assessed in lung, heart, and mediastinum regions of interest on early and late planar images in 951 heart failure patients and 94 controls. Cox regression analyses were performed to identify factors associated with outcome events during a median 17 month follow-up. ResultsHeart failure subjects with pulmonary disease had significantly reduced late lung-to-mediastinum (L/M) ratios compared to heart failure subjects without pulmonary disease. Late L/M ratio was greater in heart failure subjects without outcome events than either subjects with events or healthy controls. L/M ratio was an independent predictor of all-cause mortality. Subjects with combined favorable prognosis L/M ratio ≥ 1.7 and heart-to-mediastinum ratio (H/M) ≥ 1.6 had a significantly lower 2-year mortality (2.0%) than subjects with unfavorable L/M ratio < 1.7 and H/M ratio < 1.6 (17.7% 2-year mortality, P < .0008). ConclusionsIncreased 123I-MIBG lung activity in heart failure subjects, compared to controls, is associated with a relatively low risk of adverse events, including all-cause mortality. L/M ratio may, therefore, be useful to provide incremental prognostic information on 123I-MIBG imaging.

Current management of patients with pheochromocytoma.

Pheochromocytomas are neuroendocrine catecholamine secreting tumors that arise from chromaffin cells of the adrenal medulla or rarely from the sympathetic and parasympathetic ganglions. They have a wide spectrum of pathological and clinical manifestations. Headache, sweating and palpitations, combined with persistent or paroxysmal hypertension, are described as the most typical and highly specific, but far less sensitive symptoms. Due to better availability and accessibility of imaging procedures, an increasing proportion of pheochromocytomas are discovered incidentally upon abdominal imaging, stressing the importance of appropriate screening in all patients with adrenal incidentaloma. The diagnosis of pheochromocytoma is confirmed by measuring catecholamines and metanephrines in a 24-hour urine collection. Biochemical confirmation is followed by abdominal CT (or MR) imaging and 123I–metaiodobenzylguanidine radioisotope scanning to locate the tumor. Imaging phenotype of pheochromocytoma is well defined and should sometimes guide the management in asymptomatic patients with normal biochemical tests. A significant progress has been made in understanding the genetic determinism of these tumors. Genetic testing should be offered to selected patients with appropriate phenotype. The only curative treatment is surgical. A laparoscopic approach after careful preoperative pharmacologic preparation with long-term alpha-adrenergic blockade is currently regarded as safe with very few complications. It is crucial to maintain a high index of suspicion for pheochromocytoma, as the tumor is highly curable when recognized and potentially lethal when missed. The literature review was complemented by retrospective analysis of pheochromocytoma patients treated at our institution from 2006 to 2010. Our results are comparable to results published in recent papers and in accordance with current guidelines.

症例 I-123 metaiodobenzylguanidine心筋シンチグラフィにて長期にわたり経過観察しえた破傷風の1例

症例 I-123 metaiodobenzylguanidine心筋シンチグラフィにて長期にわたり経過観察しえた破傷風の1例

Cardiovascular impairment in a patient with acute myelitis

Case report. to report and discuss the development of sudden symptomatic sinus bradycardia in a 35-year-old woman with acute myelitis. A 35-year-old woman presented rapidly progressive weakness and hypoesthesia in the left hemibody. Five days after symptom onset, she developed symptomatic sinus bradycardia up to 30 b.p.m. Bradycardia was completely resolved ∼36 h after its onset. Cervical spine magnetic resonance imaging showed a focal T2-hyperintense intramedullary lesion at C2 level, with moderate cord swelling. The lesion involved bilaterally dorsal funiculi, and left lateral and ventral funiculi. Cardiac I-123 metaiodobenzylguanidine (MIBG) scintigraphy showed a decreased cardiac MIBG uptake suggesting sympathetic denervation. The most likely explanation for bradycardia in our patient is the myelitis-related disruption of descending vasomotor pathways, resulting in sympathetic hypoactivity. Our case extends the spectrum of the clinical presentations of cervical myelitis and emphasizes the importance of careful cardiac monitoring in acute phase of cervical myelitis.