结节病易误诊,据王洪武等~([1])收集国内18篇关于此病误诊的文献,误诊率高达63.2%,当然有误诊就会有误治,如孙永昌等~([2])报道26例结节病在影像学检查诊断的第一印象中拟诊结核5例,其中就有2例完成规范的抗结核治疗,为此应引起临床对本病诊治的重视。

Sarcoidosis

The continuing advances in computed tomographic (CT) technology in the past decades have provided ongoing opportunities to improve CT image quality and clinical practice and discover new clinical CT imaging applications. New CT technology, however, has introduced new challenges in clinical radiology practice. One of the challenges is with intravenous contrast medium administration and scan timing. In this article, contrast medium pharmacokinetics and patient, contrast medium, and CT scanning factors associated with contrast enhancement and scan timing are presented and discussed. Published data from clinical studies of contrast medium and physiology are reviewed and interpreted. Computer simulation data are analyzed to provide an in-depth analysis of various factors associated with contrast enhancement and scan timing. On the basis of basic principles and analysis of the factors, clinical considerations and modifications to protocol design that are necessary to optimize contrast enhancement for common clinical CT applications are proposed.

Intravenous Contrast Medium Administration and Scan Timing at CT: Considerations and Approaches

Objective To systematically review the current preoperative diagnostic modalities, surgical treatments, and glandular pathologies associated with primary hyperparathyroidism. Study design A systematic literature review. Results Of the 20,225 cases of primary hyperparathyroidism reported, solitary adenomas (SA), multiple gland hyperplasia disease (MGHD), double adenomas (DA), and parathyroid carcinomas (CAR) occurred in 88.90%, 5.74%, 4.14%, and 0.74% of cases respectively. Tc99m-sestamibi and ultrasound were 88.44% and 78.55% sensitive, respectively, for SA, 44.46% and 34.86% for MGHD, and 29.95% and 16.20% for DA, respectively. Postoperative normocalcemia was achieved in 96.66%, 95.25%, and 97.69% of patients offered minimally invasive radio-guided parathyroidectomy (MIRP), unilateral, and bilateral neck exploration (BNE). Intraoperative PTH assays (IOPTH) were helpful in approximately 60% of bilateral neck exploration conversion (BNEC) surgeries. Conclusion The overall prevalence of multiple gland disease (MGD and DA) was lower than often suggested by conventional wisdom. Furthermore, preoperative imaging was less accurate than it is often perceived for accurately imaging MGD. MIRP and UNE were more successful in achieving normocalcemia than is typically quoted. IOPTH was a helpful but not “fool-proof” adjunct in parathyroid exploration surgery. Significance These results support a greater role for the treatment of primary hyperparathyroidism using less invasive approaches. EMB rating: B-3.

A systematic review of the diagnosis and treatment of primary hyperparathyroidism from 1995 to 2003

High serum IgG4 concentrations in patients with sclerosing pancreatitis

There is a broad spectrum of neurogenic tumors that involve the abdomen. These tumors can be classified as those of (a) ganglion cell origin (ganglioneuromas, ganglioneuroblastomas, neuroblastomas), (b) paraganglionic system origin (pheochromocytomas, paragangliomas), and (c) nerve sheath origin (neurilemmomas, neurofibromas, neurofibromatosis, malignant nerve sheath tumors). Abdominal neurogenic tumors are most commonly located in the retroperitoneum, especially in the paraspinal areas and adrenal glands. All of these tumors except neuroblastomas and ganglioneuroblastomas are seen in adult patients. Abdominal neurogenic tumor commonly manifests radiologically as a well-defined, smooth or lobulated mass. Calcification may be seen in all types of neurogenic tumors. The diagnosis of abdominal neurogenic tumor is suggested by the imaging appearance of the lesion, including its location, shape, and internal architecture. Benign and malignant neurogenic tumors are difficult to differentiate unless distant metastatic foci are seen. For malignant tumors, imaging modalities other than computed tomography (CT) and magnetic resonance (MR) imaging may be necessary for staging. However, because most neurogenic tumors in adults are benign, CT and MR imaging can be used to develop a differential diagnosis and help determine the immediate local extent of tumor.

https://pubs.rsna.org/doi/pdf/10.1148/rg.231025050

Neurogenic tumors in the abdomen: tumor types and imaging characteristics.

PURPOSE: To determine the optimal dose of intravenous contrast material for helical computed tomography (CT) of the abdomen on the basis of patient weight. MATERIALS AND METHODS: A prospective randomized study of helical CT of the abdomen was performed by using different doses of intravenous contrast material in 221 patients (mean body weight, 57.3 kg) who were assigned randomly to three groups receiving 1.5, 2.0, or 2.5 mL/kg or a fixed dose of 100 mL of iopamidol 300. The degree of enhancement was scored visually. The CT numbers (HU) of the aorta, portal vein, liver, and pancreas were obtained at three levels of the abdomen. RESULTS: In arterial enhancement, the 2.0 mL/kg, 2.5 mL/kg, and fixed-dose groups were significantly better than the 1.5 mL/kg group, but there was no significant difference among the 2.0 mL/kg, 2.5 mL/kg, or fixed-dose groups. The degree of enhancement of the liver, pancreas, and portal vein increased with larger doses. At visual analysis, hepatic parenchymal enhancement was graded...

Abdominal Helical CT: Evaluation of Optimal Doses of Intravenous Contrast Material—A Prospective Randomized Study

RESULTS: In arterial enhancement, the 2.0 mL/kg, 2.5 mL/kg, and fixed-dose groups were significantly better than the 1.5 mL/kg group, but there was no significant difference among the 2.0 mL/kg, 2.5 mL/kg, or fixed-dose groups. The degree of enhancement of the liver, pancreas, and portal vein increased with larger doses. At visual analysis, hepatic parenchymal enhancement was graded as good or excellent in 64% of the 1.5 mL/kg, 85% of the 2.0 mL/kg, 94% of the 2.5 mL/kg, and 65% of the fixed-dose groups. CONCLUSION: When dose was tailored to patient weight, the use of 2.0 ‐2.5 mL/kg of intravenous contrast material produced better results than did 1.5 mL/kg or a fixed dose. Arterial enhancement did not differ among the 2.0 mL/kg, 2.5 mL/kg, or fixed-dose groups.

Abdominal Helical CT: Evaluation of Optimal Doses of Intravenous Contrast Material—A Prospective

Purpose
We evaluated the efficacy of using the apparent diffusion coefficient (ADC) to differentiate soft tissue tumors.

Diffusion-weighted imaging of soft tissue tumors: usefulness of the apparent diffusion coefficient for differential diagnosis.

Purpose: The purpose of this work was to compare dynamic MRI (D-MRI) with dynamic CT (D-CT) for the diagnosis of peripheral cholangiocarcinoma (PCC) of the liver. Method: Twenty patients with PCC underwent both D-CT and D-MRI during the early, middle, and delayed phase after contrast medium administration. The findings from D-MRI were compared with those from D-CT. Results: D-CT and D-MRI exhibited a similar tumoral enhancement pattern, and this enhancement was more conspicuous on D-MRI. A wedge-like enhancement area peripheral to the tumor was observed in 9 (45%) patients on D-CT and 11 (55%) patients on D-MRI. Ductal dilatation was found in 13 (65%) patients on both techniques. Vascular involvement and extrahepatic invasion were seen in nine (45%) and two (10%) patients, respectively. The relationship of the tumor to the vessels and surrounding organs was more easily evaluated on D-CT. Conclusion: Both D-CT and D-MRI can provide important information for the diagnosis of PCC. D-CT is better than D-MRI for demonstrating vascular involvement and extrahepatic invasion. D-MRI gives more conspicuous enhancement.

Intrahepatic peripheral cholangiocarcinoma: comparison of dynamic CT and dynamic MRI.

Magnetic resonance (MR) imaging has an increasing role in evaluating soft-tissue masses of the extraperitoneal spaces. Since the MR imaging features of most soft-tissue masses are nonspecific, prediction of a specific histologic diagnosis remains a challenge for the radiologist. However, there are certain specific MR imaging appearances that are helpful for more accurate diagnosis. Some histologic components, such as myxoid stroma, collagen fibers, calcification, and fat, have characteristic MR imaging features. Recognition of these features can assist the radiologist in limiting the differential diagnosis. Dynamic enhancement patterns can reflect the vascularity of masses and may be useful in diagnosis, especially in differentiating benign from malignant soft-tissue masses. Familiarity with specific signs and knowledge of diagnostic pitfalls are also important for shortening the list of differential diagnoses. Specific signs are the target sign, the bowl of fruit sign, a whorled appearance, a flow void, speckled enhancement, associated lymphadenopathy, and extension into the intervertebral foramen. Diagnostic pitfalls are as follows: a myxoid stroma simulating cystic degeneration and necrosis, collagen fibers simulating hemorrhage, a fat component simulating extraperitoneal fat, extensive intratumoral hemorrhage simulating hematoma, benign masses mimicking malignant ones, malignant masses mimicking benign ones, and peritoneal lesions mimicking extraperitoneal masses.

https://pubs.rsna.org/doi/pdf/10.1148/radiographics.21.5.g01se141141

Masafumi Uchida

Papers

Abdominal Helical CT: Evaluation of Optimal Doses of Intravenous Contrast Material—A Prospective Randomized Study

Abdominal Helical CT: Evaluation of Optimal Doses of Intravenous Contrast Material—A Prospective

Diffusion-weighted imaging of soft tissue tumors: usefulness of the apparent diffusion coefficient for differential diagnosis.

Intrahepatic peripheral cholangiocarcinoma: comparison of dynamic CT and dynamic MRI.

MR Imaging of Soft-Tissue Masses of the Extraperitoneal Spaces