Long-term disease-free survival after MIBG therapy for metastatic pheochromocytoma.

Pheochromocytomas are rare tumours originating in chromaffin cells, representing 0.1%-1% of all secondary hypertension cases. The majority are benign and unilateral, characterised by the production of catecholamines and other neuropeptides. Mainly located in the adrenal gland, they are more frequent between the third and fifth decades of life. Iodine-131 metaiodobenzylguanidine (131I-MIBG), a radiopharmaceutical agent used for scintigraphic localisation of pheochromocytomas, has been employed to treat malignant pheochromocytomas since 1983 in a few specialised centres around the world. We reviewed our clinical experience in one such case of a young lady who presented with history of abdominal pain, headache and lower back pain. On evaluation, ultrasonography revealed a right adrenal mass and elevated urine vanillylmandelic acid levels. Following surgical resection and histopathological confirmation of pheochromocytoma, MIBG scintigraphy revealed osseous metastases and hence, she underwent 131I-MIBG therapy.

Efficacy of Empirical 131 I Radioiodine Therapy in Well-Differentiated Thyroid Carcinoma Patients With Thyroglobulin-Elevated Negative Iodine Scintigraphy Syndrome : A Systematic Review and Meta-analysis.

OBJECTIVES: This study aimed to perform a systematic review and meta-analysis on the efficacy of empirical high-dose radioiodine therapy in treating differentiated thyroid cancer patients with thyroglobulin (Tg)-elevated negative iodine scintigraphy (TENIS) syndrome. METHODS: We searched PubMed, EMBASE, and the Cochrane Library to identify relevant studies published until April 2022. This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist and registered in an international prospective register of systematic reviews (PROSPERO). Meta-analyses of proportions and odds ratios were performed to assess the beneficial effect of empirical high-dose radioiodine therapy in patients with TENIS syndrome. Subgroup analysis was also performed according to the presence of micrometastasis or macrometastasis. RESULTS: We identified 14 studies including 690 patients who received empirical high-dose radioiodine therapy for TENIS syndrome. Those who had micrometastasis exhibited additional lesions not previously observed on diagnostic whole-body scan (prop = 0.64, 95% confidence interval [CI], 0.51-0.77) and had reduced serum Tg levels (prop = 0.69; 95% CI, 0.52-0.84) after empirical radioiodine treatment. No such findings were observed among patients with macrometastasis. Moreover, we found that the empirical radioiodine treatment group had lower serum Tg levels than did controls (odds ratio = 0.27; 95% CI, 0.09-0.87), which suggests a lower risk of disease progression. CONCLUSIONS: Our findings indicate that empirical high-dose radioiodine therapy promoted beneficial effects and could be recommended for patients with TENIS syndrome, especially those with micrometastasis.

The Role of Scintigraphy with Bone Radiotracers in Cardiac Amyloidosis.

Cardiac amyloidosis (CA) is caused by the myocardial deposition of misfolded proteins, either amyloid transthyretin (ATTR) or immunoglobulin light chains (AL). The paradigm of this condition has transformed, since CA is increasingly recognized as a relatively prevalent cause of heart failure. Cardiac scintigraphy with bone tracers is the unique noninvasive technique able to confirm CA without performing tissue biopsy or advanced imaging tests. A moderate-to-intense myocardial uptake (Perugini grade ≥2) associated with the absence of a monoclonal component is greater than 99% specific for ATTR-CA, while AL-CA confirmation requires tissue biopsy.

A case of renal sarcoidosis complicated by parotid gland and uterine lesions.

BACKGROUND: Sarcoidosis is a systemic disease that can affect multiple organs. While pulmonary sarcoidosis is most commonly observed, renal sarcoidosis occurs less frequently. We herein report a case of sarcoidosis with an exceptionally rare distribution including renal lesions. CASE PRESENTATION: A 51-year-old Japanese female was referred because of bilateral parotid swelling and renal dysfunction. Computed tomography scan showed the swelling of bilateral kidneys, parotid glands, and uterus. Ga scintigraphy also showed remarkable accumulation in these organs. Renal biopsy and cytological evaluations of parotid gland and uterus were performed and she was diagnosed as sarcoidosis of these organs. Treatment was initiated with prednisolone 40 mg/day and then renal dysfunction subsequently improved. In addition, the swelling of parotid glands and uterus improved and Ga accumulation in each organ had disappeared. CONCLUSION: This is a first case of renal sarcoidosis complicated by parotid glands and uterus lesions. Pathological findings and the reactivity observed in Ga scintigraphy indicated the presence of lesions in these organs.

Application of small bowel capsule endoscopy in children with Meckel's diverticulum.

BACKGROUND: Meckel diverticulum (MD) is an important cause of gastrointestinal bleeding in children. Small bowel capsule endoscopy (SBCE) is a first-line examination method applied to patients with obscure gastrointestinal bleeding, but there are few studies on its application in children with MD. This article aims to provide evidence in favor of the auxiliary diagnosis of MD in children by analyzing its characteristics using SBCE. METHODS: We retrospectively collected the clinical data of patients with suspected MD. RESULTS: A total of 58 children were included in this study. All 58 children presented overt gastrointestinal bleeding (bloody stool or melena). Capsule endoscopy identified protruding lesions in 2 cases, double-lumen changes in 30 cases (all considered as MD), vascular lesions in 7 cases, intestinal mucosal inflammatory lesions in 3 cases, ulcers or erosion in 3 cases, and no obvious abnormalities in SBCE in 12 cases. Both SBCE and technetium-99 scans were performed for 24 cases, 22 of which were diagnosed MD by their combined results, giving a diagnostic coincidence rate of 91.7%. Eight cases were highly suspected as MD but were negative for the technetium-99 scan and positive for SBCE. CONCLUSION: SBCE has high accuracy in the diagnosis of MD in children, especially when performed in combination with a technetium-99 scan, which can greatly improve the diagnostic rate of MD in children.

Can CT or MRI volumetry substitute scintigraphy in living kidney donor evaluation? A systematic review.

BACKGROUND: Current potential living kidney donor's assessment includes functional and anatomical evaluation. Scintigraphy is recommended in some cases and some centers include this test in the donor's protocol. Recent studies advocate for the avoidance of this test as CT or MRI volumetry showed to accurately assess donor's renal function. OBJECTIVE: To summarize scientific evidence on image tests for pre-donation and/or post-nephrectomy renal function evaluation. EVIDENCE ACQUISITION: This review followed the guidelines set by the European Association of Urology and adhered to PRISMA 2020 recommendations. The protocol was registered in PROSPERO on 10th December 2022 (ID: CRD42022379273). EVIDENCE SYNTHESIS: Twenty-one studies met the inclusion criteria after thorough screening and eligibility assessment. According to QUADAS-2, patient selection and flow/timing domains showed a predominant low risk of bias. The correlation between split renal function (SRF) using CT and scintigraphy varied from weak (r = 0.21) to remarkably strong (r = 0.949). Bland-Altman agreement demonstrated moderate to excellent results, with mean differences ranging from -0.06% to 1.76%. The correlation between split renal volume (CT) and estimated glomerular filtration rate (eGFR) at 6 months or 1 year after nephrectomy showed a moderate correlation, with coefficients ranging from 0.708 to 0.83. The correlation between SRF (MRI) and renal scintigraphy reported a moderate correlation, with correlation coefficients of 0.58 and 0.84. MRI and scintigraphy displayed a good agreement, with a 66% agreement observed and mean differences of ± 0.3%. CONCLUSIONS: Despite study heterogeneity, MRI or CT-based renal volumetry appears promising compared to scintigraphy, with favorable correlations and agreement.

Scintigraphy of Gastrointestinal Motility: Best Practices in Assessment of Gastric and Bowel Transit in Adults.

Various radiologic examinations and other diagnostic tools exist for evaluating gastrointestinal diseases. When symptoms of gastrointestinal disease persist and no underlying anatomic or structural abnormality is identified, the diagnosis of functional gastrointestinal disorder is frequently applied. Given its physiologic and quantitative nature, scintigraphy often plays a central role in the diagnosis and treatment of patients with suspected functional gastrointestinal disorder. Most frequently, after functional gallbladder disease is excluded, gastric emptying scintigraphy (GES) is considered the next step in evaluating patients with suspected gastric motility disorder who present with upper gastrointestinal symptoms such as dyspepsia or bloating. GES is the standard modality for detecting delayed gastric emptying (gastroparesis) and the less commonly encountered clinical entity, gastric dumping syndrome. Additionally, GES can be used to assess abnormalities of intragastric distribution, suggesting specific disorders such as impaired fundal accommodation or antral dysfunction, as well as to evaluate gastric emptying of liquid. More recently, scintigraphic examinations for evaluating small bowel and large bowel transit have been developed and validated for routine diagnostic use. These can be performed individually or as part of a comprehensive whole-gut transit evaluation. Such scintigraphic examinations are of particular importance because clinical assessment of suspected functional gastrointestinal disorder frequently fails to accurately localize the site of disease, and those patients may have motility disorders involving multiple portions of the gastrointestinal tract. The authors comprehensively review the current practice of gastrointestinal transit scintigraphy, with diseases and best imaging practices illustrated by means of case review. ©RSNA, 2024 See the invited commentary by Maurer and Parkman in this issue.

First episode of febrile urinary tract infection in children, detection and risk factors of kidney scarring: A prospective cohort study.

AIMS: This prospective study aimed to evaluate the characteristics and findings of children who presented with acute pyelonephritis (APN) and to determine the independent risk factors for kidney scarring. MATERIAL AND METHODS: Patients who satisfied the following criteria were enrolled in the study: first known episode of APN; at least two of the following findings: fever ≥ 38.5 °C, white blood cell count ≥ 10,000/mm3, erythrocyte sedimentation rate ≥ 20 mm/h, C-reactive protein ≥ 20 mg/dL; absence of congenital abnormalities or other kidney and systemic diseases, except vesicoureteral reflux (VUR); no APN relapses until the time of kidney scar detection. 99mTc-Dimercaptosuccinic acid kidney scintigraphy (99mTc-DMSA) was performed at admission, along with a kidney ultrasound. Follow-up 99mTc-DMSA took place after 6 months. Radiographic cystourethrography for VUR detection and grading was performed 1 month after the acute infection. RESULTS: We enrolled 70 children in the study. The kidney ultrasound failed to diagnose more than half of the cases of APN. VUR was found in 21.5% of children. 75% had findings of APN in the acute phase through 99mTc-DMSA, while in the second 99mTc-DMSA, there was a complete remission in 68% of them. Scars were observed more frequently in older children, children with VUR grade ≥ III, and children not on antibiotic prophylaxis. CONCLUSION: VUR did not appear to be associated with the first episode of APN, and children older than 1 year of age had a higher risk of scarring. Antibiotic prophylaxis may prevent kidney scarring due to host immunomodulatory effects, but more studies are needed so that conclusions can be drawn.

The Utility of Sulfur Colloid Imaging to Differentiate Charcot's Neuroarthropathy from Osteomyelitis: A Case Study.

Charcot's neuroarthropathy and osteomyelitis can have similar initial presentations. The ability to differentiate between the two pathologic conditions is essential, as each requires different treatment. We present a case of a 53-year-old woman with pain, swelling, and warmth in her left first metatarsophalangeal joint and first tarsometatarsal joint. Radiographs showed comminuted fractures at the base of the first metatarsal. Osteomyelitis was suspected by the primary team based on physical findings and a history of previous first metatarsophalangeal joint arthrodesis. A triphasic bone scan and an indium white blood cell scan were positive for osteomyelitis. The podiatric medical team was suspicious for possible Charcot's neuroarthropathy based on physical findings and uncontrolled blood glucose levels at the time of her previous arthrodesis. A sulfur colloid scan was performed and compared with an indium scan, which showed no evidence of osteomyelitis. This case demonstrates the usefulness of sulfur colloid imaging compared with an indium white blood cell scan to differentiate osteomyelitis from Charcot's neuroarthropathy. This case also highlights the importance of using clinical judgment to make the correct diagnosis.

Scintigraphic and Echocardiographic Study of Patients with Pathogenic or Probably Pathogenic Variants of the TTR Gene without Overt Cardiac Involvement. / Avaliação Cintilográfica e Ecocardiográfica em Portadores de Variantes Patogênicas ou Provavelmente Patogênicas do Gene TTR sem Envolvimento Cardíaco Manifesto.

BACKGROUND: Transthyretin amyloidosis (ATTR) is an infiltrative disease caused by abnormal protein deposition mainly in the heart and peripheral nervous system. When it affects the heart, the disease presents as restrictive cardiomyopathy; when it affects the peripheral and autonomic nervous system, it manifests as polyneuropathy, and is called familial amyloid polyneuropathy (FAP). There are two ATTR subtypes: wild-type ATTR, where there is no mutation, and mutant ATTR (ATTRm), which is characterized by a mutation in the gene encoding the transthyretin protein (TTR). In both subtypes, cardiac involvement is the major marker of poor prognosis. OBJECTIVES: To assess the prevalence of subclinical cardiac involvement in a sample of patients with TTR gene mutation by using pyrophosphate scintigraphy and strain echocardiography; to compare scintigraphy and strain findings; to evaluate the association between neurological manifestations (FAP) and subclinical cardiac involvement; and to analyze whether there is an association between any specific mutation and cardiac involvement. METHODS: This is a cross-sectional study with carriers of the TTR gene mutation, without cardiovascular symptoms or changes in electrocardiographic or conventional echocardiographic parameters. All patients underwent pyrophosphate scintigraphy and strain echocardiography. Subclinical cardiac involvement was defined as a Perugini score ≥ 2, heart-to-contralateral lung (H/CL) ratio ≥ 1.5 at 1 h, H/CL ≥1.3 at 3 h, or global longitudinal strain (GLS) ≤ -17%. Descriptive and analytical analyses were performed and Fisher's exact test and Mann-Whitney test were applied. A value of p < 0.05 was considered significant. RESULTS: The 23 patients evaluated had a median age of 51 years (IQR 37-57 years), 15 (65.2%) were female, 12 (52.2%) were Pardo, nine (39.1%) had systemic arterial hypertension, and nine (39.1%) had a previous diagnosis of FAP. Of the nine patients with FAP, 8 (34.8%) were on tafamidis. The associated mutations were Val142IIe, Val50Met, and IIe127Val. The median GLS in the sample was -19% (-16% to -20%). Of the 23 patients, nine (39.1%; 95% CI = 29-49%) met criteria for cardiac involvement, six (26%) by the GLS-based criteria only. There was no association between having FAP and being an asymptomatic carrier, as assessed by strain echocardiography and pyrophosphate scintigraphy (p = 0.19). The prevalence of systemic arterial hypertension, diabetes mellitus, dyslipidemia, smoking, and reduced GLS did not differ between groups. Septal e' wave velocity was the only variable that significantly differed between individuals with and without reduced GLS, with an area under the ROC curve of 0.80 (95% CI = 0.61-0.98, p = 0.027). The best diagnostic accuracy was achieved with a septal e' velocity ≤ 8.5 cm/s. There was no association between mutation type and preclinical cardiac involvement, nor between tafamidis use and lower degree of cardiac involvement (37.5% versus 40.0%, p = 0.90). CONCLUSION: Subclinical cardiac involvement was common in a sample of TTR mutation carriers without cardiac involvement. Reduced left ventricular GLS was the most frequent finding. There was no association between the presence of amyloid polyneuropathy and subclinical cardiac involvement. Type of mutation was not associated with early cardiac involvement. In this sample, the use of tafamidis 20 mg/day was not associated with a lower prevalence of subclinical cardiac involvement.

FUNDAMENTO: A amiloidose por transtirretina (ATTR) é uma doença infiltrativa causada pela deposição anormal de proteína principalmente no coração e no sistema nervoso periférico. Quando acomete o coração, a doença manifesta-se como uma cardiomiopatia restritiva e, quando afeta o sistema nervoso periférico e autônomo, apresenta-se como uma polineuropatia, podendo ser chamada de Polineuropatia Amiloidótica Familiar (PAF). Existem dois subtipos de ATTR, a ATTR selvagem, em que não há variantes genéticas, e a ATTR hereditária, caracterizada por uma variante no gene que codifica a proteína transtirretina (T\TR). Em ambos os subtipos, o envolvimento cardíaco é o principal marcador prognóstico. OBJETIVOS: Avaliar a prevalência do envolvimento cardíaco subclínico em uma amostra de pacientes com variantes genéticas no gene TTR usando a cintilografia com pirofosfato e o ecocardiograma com strain; comparar os achados cintilográficos e as medidas de strain; avaliar a associação entre PAF e o envolvimento subclínico; e analisar se existe uma associação entre uma variante genética específica e o envolvimento cardíaco. MÉTODOS: Estudo transversal com carreadores de variantes no gene TTR sem sintomas cardiovasculares e sem alterações nos parâmetros da eletrocardiografia ou do ecocardiograma convencional. Todos os pacientes foram submetidos à cintilografia com pirofosfato e à ecocardiografia com análise de strain. O envolvimento cardíaco subclínico, definido como um escore de Perugini ≥ 2, razão Coração (C)/ Hemitórax Contralateral (CL) ≥ 1,5 em uma hora, C/CL ≥ 1,3 na terceira hora, ou um strain longitudinal global (SGL) ≤ −17%. Realizadas análises descritiva e analítica, e aplicados o teste exato de Fisher e o teste de Mann-Whitney. Um valor de p<0,05 foi considerado significativo. RESULTADOS: Os 23 pacientes avaliados apresentavam uma idade mediana de 51 (37-57) anos, 15 (65,2%) eram do sexo feminino, 12 (52,2%) eram pardos, nove (39,1%) apresentavam hipertensão arterial sistêmica, e nove (39,1%) tinham um diagnóstico prévio de PAF. Dos nove pacientes com PAF, oito (34,8%) usavam tafamidis. As variantes genéticas identificadas foram Val142IIe, Val50Met e IIe127Val. O valor mediano do SGL foi −19% (-16% ­ −20%). Dos 23 pacientes, nove (39,1%; 95% CI = 29­49%) preencheram os critérios de envolvimento cardíaco, seis (26%) somente pelo critério do SGL. Não houve associação entre PAF e um carreador assintomático avaliado por ecocardiograma com análise de strain e pela cintilografia com pirofostato (p=0,19). A prevalência de hipertensão arterial sistêmica, diabetes mellitus, dislipidemia, tabagismo e SGL reduzido não foi diferente entre os grupos. A velocidade da onda e' septal foi a única variável que apresentou diferença significativa entre os indivíduos com e sem SGL reduzido, com uma área sob a curva ROC de 0,80 (IC95% = 0,61­0,98, p = 0,027). A melhor acurácia diagnóstica foi alcançada com uma velocidade e' septal ≤ 8,5 cm/s. Não houve associação entre o tipo de variante genética e o envolvimento cardíaco pré-clínico, nem entre o uso de tafamidis e este mesmo envolvimento (37,5% versus 40,0%, p = 0,90). CONCLUSÃO: O envolvimento cardíaco subclínico foi frequente em uma amostra de carreadores da variante genética do gene TTR. Um valor do SGL reduzido foi o achado mais comum. Não houve associação entre a presença de polineuropatia amiloidótica e o envolvimento subclínico. O tipo de variante genética não foi associado com envolvimento cardíaco precoce. Nesta amostra, o uso de tafamidis (20mg/dia) não foi associado com uma menor prevalência de envolvimento cardíaco subclínico.

Ultrasonographic Detective Flow Imaging for Evaluating Parathyroid Adenoma in Patients with Primary Hyperparathyroidism.

BACKGROUND: Detective flow imaging (DFI) is a new imaging technology that displays low-velocity blood flow, which is difficult to visualize on conventional color Doppler ultrasonography (CDU). In this study, we compared the usefulness of DFI with that of CDU and methoxy-isobutyl-isonitrile (MIBI) scintigraphy for detecting parathyroid adenoma (PA) in patients with primary hyperparathyroidism (PHPT). METHODS: From March 2021 to March 2023, 87 PHPT patients underwent surgery, and 66 had a single PA. We performed preoperative conventional ultrasonography with CDU, MIBI scintigraphy, and DFI for 42 patients (5 males and 37 females; mean age: 61.6 ± 15.4 years). RESULTS: MIBI scintigraphy detected PA in 85.7% (36/42) patients, and both CDU and DFI detected PA in all patients. The rates of vascularity in PA detected by CDU and DFI were 71.4% (30/42) and 85.7% (36/42), respectively. Vascularity was detected by DFI in 6 patients who were negative for vascularity on MIBI scintigraphy. Furthermore, DFI detected blood supply in 6 of the 12 patients with undetectable blood supply on CDU. Fisher's exact test revealed that high or low blood flow, as determined by DFI, was significantly associated with detection of feeding vessels in PA by CDU (P < 0.001). CONCLUSIONS: DFI was useful for preoperative detection of PA blood flow.

Radioiodine Uptake at Suture Site Granuloma Mimicking Neck Node Metastasis on 131 I Whole-Body Iodine Scintigraphy.

ABSTRACT: Differentiated thyroid carcinoma constitutes over 90% of all thyroid cancers. The standard treatment approach involves total or near-total thyroidectomy with or without neck dissection followed by 131 I whole-body scintigraphy (WBS) to detect local or distant metastases. Radioiodine offers high sensitivity and specificity for detection of metastatic disease in well differentiated thyroid carcinoma. However, despite its high accuracy, 131 I WBS demonstrates false-positive results, mostly at inflammatory or infective site. These false-positive radioiodine accumulation can lead to misdiagnosis and unwarranted radioiodine treatment. This case presents localization of 131 I to the suture site granuloma leading to false-positive results on 131 I WBS.

"Loss of Bone Signal" on 99m Tc-Labeled Pyrophosphate Scintigraphy in a Patient With Wild-Type Transthyretin Amyloidosis.

ABSTRACT: 99m Tc-3,3-diphosphono-1,2-propanedicarboxylic acid (DPD) scintigraphy and 99m Tc-pyrophosphate (PYP) scintigraphy are highly sensitive modalities for imaging both myocardial and extracardiac amyloid transthyretin in patients with wild-type transthyretin (ATTRwt) amyloidosis. "Loss of bone signal" on planar imaging of 99m Tc-DPD scintigraphy, in which the tracer uptake in bone is obscured by marked tracer uptake in the overlying skeletal muscles, is reported. However, this phenomenon has not yet been documented on 99m Tc-PYP scintigraphy. We describe an 89-year-old woman with ATTRwt amyloidosis in whom "loss of bone signal" together with marked tracer uptake into the skeletal muscles was clearly demonstrated on 99m Tc-PYP scan.

Electrocardiographic, biochemical, and scintigraphic evidence for the cardioprotective effect of paricalcitol and vitamin D3 on doxorubicin-induced acute cardiotoxicity in rats.

AIM: We aimed to investigate the possible cardioprotective effects of paricalcitol (PR), its vitamin D receptor agonist, and vitamin D3 (VIT-D3) on an experimental model of doxorubicin (DX) cardiotoxicity by 99mTc-PYP scintigraphy, electrocardiographic (ECG) and biochemical methods. METHOD: Forty-two male Wistar/Albino rats (250‒300 g; aged 10‒12 weeks) were randomly separated into six groups, namely into control (CN), doxorubicin (DX), paricalcitol (PR), vitamin D3 (VIT-D3), paricalcitol + doxorubicin (PR+DX), and vitamin D3 + doxorubicin (VIT-D3+DX) groups. Cardiotoxicity was induced by three doses of DX (18 mg/kg, i.p.) at 24-hour intervals on days 18, 19 and 20. PR (0.5 ug/ kg, i.p) and VIT-D3 (5,000 IU/kg, i.p) were injected for 20 days before and after the application of DX (18 mg/kg, i.p.). On day 21 of the experiment, biochemical parameters [tumor necrosis factor TNF-alpha (TNF-α); interleukin-6 (IL-6), nitric oxide (NO), and cardiac troponin T (cTnT)], as well as ECG and scintigraphic (99mTc-PYP) features were assessed. RESULTS: Compared to CN, DX significantly raised TNF-α, IL-6, and NO in heart tissue, cTnT in serum, 99mTc-PYP uptake in the myocardium, and ECG parameters, specifically QRS complex duration, QT interval duration, and ST-segment amplitude, while also reducing heart rate (p<0.001). Pretreatment with PR and VIT-D3 mitigated these abnormalities produced by DX in the heart (p<0.001). CONCLUSION: Results show that vitamin D receptor agonist paricalcitol and vitamin D protect against DX-induced cardiotoxicity through anti-inflammatory and antioxidant effects (Fig. 4, Ref. 59). Text in PDF www.elis.sk Keywords: paricalcitol, doxorubicin, vitamin D, ECG, 99mTc-PYP scintigraphy, cardiotoxicity, inflammation.

Gastrointestinal radionuclide imaging in pediatric age group.

Pediatric gastrointestinal imaging plays a crucial role in evaluating and managing digestive system disorders in children. This comprehensive review dives into the nuances of pediatric gastrointestinal imaging techniques, focusing on three specific modalities: gastric emptying scintigraphy (GES), intestinal transit scintigraphy (ITS), and gastrointestinal bleeding scintigraphy. GES involves real-time monitoring of stomach emptying using radiotracers and gamma camera technology. While challenges exist in standardizing protocols due to age-specific meal compositions, GES remains pivotal in diagnosing motility disorders, gastroesophageal reflux, and abdominal pain in children. ITS, utilizing [67Ga], provides insights into gastrointestinal motility disorders such as Hirschsprung disease. It aids in whole-gut transit evaluation, guiding surgical interventions and improving long-term clinical outcomes. Gastrointestinal bleeding scintigraphy, employing [99mTc], assists in diagnosing conditions like Meckel's diverticulum and occult bleeding, offering continuous monitoring to pinpoint the bleeding site along the entire gastrointestinal tract. SPECT-CT improves the accuracy and the standards of care. Each technique's protocol details, clinical indications, and diagnostic capabilities are thoroughly discussed, highlighting the importance of these non-invasive, functional imaging modalities in pediatric gastroenterology.

A Rare False-Positive Whole-Body Scan in a Patient With Differentiated Thyroid Cancer: Unilateral Conjunctival Concretions.

ABSTRACT: 131 I has been used effectively over the years in both diagnosis and therapy of differentiated thyroid cancer (DTC). Although whole-body scan with 131 I is a highly sensitive tool for detecting normal thyroid tissue and metastasis of DTC, it is not specific; therefore, false-positive images can be seen in clinical practice, and their recognition is critical for correct management. Evaluation of false-positive uptake is important because it may be confused with metastatic involvement. Here, we present a rare false-positive result of whole-body scan in a patient with DTC. To our knowledge, it is the first report on 131 I uptake of conjunctival concretions.