CT/MRI在随访嗅神经母细胞瘤的价值(附5例报告)

目的 评价影像学检查在随访嗅神经母细胞瘤的价值.方法 分析5例嗅神经母细胞瘤随访过程中的CT、MRI表现.结果 2例病人的存活时间超过5年. 2例就诊时病变局限于鼻腔,在随访过程中, 1例表现为右侧眼眶区硬膜外软组织肿块,同时左侧鼻腔内亦可见软组织肿块影,CT、MRI显示病变强化均匀,1个月后左侧鼻腔病变显著增大,且破坏了邻近硬腭.另1例病变则呈浸润性生长,CT显示颅底骨质广泛破坏,翼腭窝、颈动脉管、圆孔、卵圆孔均受累.MRI显示病变侵及颅内海绵窦、颈内动脉以及鞍区结构.另3例就诊时已为T4期,病变以鼻腔顶壁、筛窦为中心,侵犯颅内海绵窦以及鞍区结构,颅底骨质破坏.结论 CT/MRI可清晰地显示病变的侵袭范围,对评价病变的生物学生长行为提供了客观依据.     

Epilepsy: the role of MR imaging.

MR is the imaging technique of choice when examining a patient who is having seizures. Detection, localization, and differentiation of structural epileptogenic abnormalities are much better with MR imaging than with CT. MR imaging has a high success rate in identifying hippocampal sclerosis, a common cause of surgically treatable temporal lobe epilepsy. The affected hippocampus is atrophic and hyperintense on long TR images. Functional imaging with single-photon emission computed tomography and positron emission tomography is complementary to MR imaging but is not as widely available. In summary, MR imaging has dramatically changed the workup of epilepsy, especially for the patient with medically uncontrollable seizures. As surgical treatment of epilepsy becomes more available, the need for preoperative evaluation with MR imaging will increase.     

Multiple sclerosis: the role of MR imaging

MR offers by far the most sensitive technique for detecting multiple sclerosis (MS) lesions and has proved to be an important paraclinical tool for diagnosing MS and monitoring therapeutic trials. Technologic advances of MR in recent years have dramatically improved our understanding of MS disease. This review will focus on the contribution of MR imaging in MS and provide a discussion of conventional and advanced nonconventional MR techniques with regard to current findings, clinical correlations, and future directions.     

Achilles tendon injuries: the role of MR imaging

Eight magnetic resonance (MR) examinations were performed in seven patients with Achilles tendon injuries and correlated with physical examination and surgical and clinical follow-up. The MR examinations depicted the Achilles tendon in excellent detail and Achilles tendon abnormalities with greater accuracy than physical examination. Of five tendons shown to be at least partially torn on MR, palpable tendinous defects were found in only one, and plantarflexion weakness was found in four. The MR and surgical findings precisely correlated in one case. Magnetic resonance proved valuable in the evaluation of clinically equivocal Achilles tendon tears and may ultimately play a greater role as a research tool in the determination of optimal forms of therapy for specific Achilles tendon injuries.     

Rheumatoid knee: role of gadopentetate-enhanced MR imaging

Physical examination is often insufficient in distinguishing between joint effusion and inflamed synovium in the knee joints of patients with rheumatoid arthritis. The authors prospectively evaluated the role of intravenously administered gadopentetate dimeglumine in distinguishing between these two conditions. Fourteen patients with classic rheumatoid arthritis were examined first by a rheumatologist and then by means of magnetic resonance (MR) imaging with T1- and T2-weighted sequences. T1-weighted images were also obtained following the intravenous administration of gadopentetate dimeglumine. T1-weighted images obtained prior to contrast material administration demonstrated an identical low-intensity signal from both effusion and inflamed synovium, and T2-weighted images demonstrated increased signal intensity in both cases. Intravenous administration of gadopentetate dimeglumine allowed distinction between effusion and abnormal synovium, with the effusion remaining of low signal intensity and the synovium demonstrating enhancement and increased signal intensity. The authors conclude that the use of gadopentetate allows distinction between synovial thickening and joint effusion in the knee, which may affect treatment decisions.     

胎儿肝铁超负荷的MRI诊断方法

目的评价MRI诊断胎儿肝铁超负荷可能的方法。方法我们复习了7例胎儿肝脏异常信号的MR影像,包括临床怀疑为先天性感染(n=2)、胃肠道异常(n=3)与胎儿水肿     

Fetal liver iron overload: the role of MR imaging

Objective

To assess the potential role of MR imaging in the diagnosis of fetal liver iron overload.

Methods

We reviewed seven cases of abnormal liver signal in fetuses referred to MR imaging in a context of suspected congenital infection (n?=?2), digestive tract anomalies (n?=?3) and hydrops fetalis (n?=?2). The average GA of the fetuses was 31?weeks. The antenatal diagnoses were compared with histological data (n?=?6) and postnatal work-up (n?=?1).

Results

Magnetic resonance imaging demonstrated unexpected abnormal fetal liver signal suggestive of iron overload in all cases. The iron overload was confirmed on postnatal biopsy (n?=?2) and fetopathology (n?=?4). The final diagnosis was hepatic hemosiderosis (haemolytic anaemia (n?=?2) and syndromal anomalies (n?=?2)) and congenital haemochromatosis (n?=?3). In all cases, the liver appeared normal on US.

Conclusions

Magnetic resonance is the only imaging technique able to demonstrate liver iron overload in utero. Yet, the study outlines the fundamental role of MR imaging in cases of congenital haemochromatosis. The antenatal diagnosis of such a condition may prompt ante??(in the case of recurrence) or neonatal treatment, which might improve the prognosis.     

Acute chest pain: The role of MR imaging and MR angiography

MR imaging (MRI) and MR angiography (MRA) have gained a high level of diagnostic accuracy in cardiovascular disease. MRI in cardiac disease has been established as the non-invasive standard of reference in many pathologies. However, in acute chest pain the situation is somewhat special since many of the patients presenting in the emergency department suffer from potentially life-threatening disease including acute coronary syndrome, pulmonary embolism, and acute aortic syndrome. Those patients need a fast and definitive evaluation under continuous monitoring of vital parameters. Due to those requirements MRI seems to be less suitable compared to X-ray coronary angiography and multislice computed tomography angiography (CTA). However, MRI allows for a comprehensive assessment of all clinically stable patients providing unique information on the cardiovascular system including ischemia, inflammation and function. Furthermore, MRI and MRA are considered the method of choice in patients with contraindications to CTA and for regular follow-up in known aortic disease. This review addresses specific features of MRI and MRA for different cardiovascular conditions presenting with acute chest pain.     

Pilomatrix carcinoma: role played by MR imaging

Summary We report the magnetic resonance imaging (MRI) of a pilomatrix carcinoma. We found a soft tissue tumor of the back entering the spinal canal and compressing the spinal cord and we monitored a good response to radiotherapy and chemotherapy. We have concluded that MRI played an important role in determination of the volume, extension and management of this rare malignant tumor.     

Swollen lower extremity: role of MR imaging.

The authors assessed the use of magnetic resonance imaging in differentiating lymphedema, phlebedema, and lipedema of the lower limb. They examined 14 patients: five with lipedema, five with lymphedema, and four with phlebedema. T1- and T2-weighted transaxial sequences were performed before administration of gadolinium tetraazacyclododecane-tetraacetic acid (DOTA) and T1-weighted spin-echo sequences were performed after administration of Gd-DOTA in each patient. Images of patients with lipedema showed homogeneously enlarged subcutaneous layers, with no increase in signal intensity at T2-weighted imaging or after Gd-DOTA administration. Patients with phlebedema had areas containing increased amounts of fluid within muscle and subcutaneous fat. In lymphedema, a honeycomb pattern above the fascia between muscle and subcutis was observed, with a marked increase in signal intensity at T2-weighted imaging. After Gd-DOTA administration, there was only a slight increase in signal intensity in the subcutis in lymphedema and phlebedema and a moderate increase in signal intensity in muscle in phlebedema.     

Groin pain: clinical assessment and the role of MR imaging

Groin pain is a common problem in the elite athlete and may lead to prolonged inactivity if inadequately treated. Groin pain, arising from injuries to the hip and pelvis, accounts for 5 to 6% of athletic injuries in adults and 10 to 24% of these injuries in children. Lower limb-dominated athletic activities such as football, rugby, ice hockey, running, and ballet are particularly at risk. Comprehensive evaluation of all the anatomical locations prone to injury including the hip joint, sacrum, ilium and proximal femora, pelvic tendon attachments, and pelvic musculature is required. Magnetic resonance (MR) imaging provides superb soft tissue contrast resolution, multiplanar capabilities, and a wide field of view to evaluate many potential causes of groin pain. Careful clinical examination allows the optimal use of MR imaging and MR arthrography to evaluate the articular, osseous, tendinous, and muscular structures, which may be the source of groin pain. Accurate diagnosis is essential for appropriate management and rehabilitation plans. This article reviews the role of clinical assessment in guiding diagnostic imaging and also describes the relevant MR imaging findings in athletes presenting with groin pain.     

Acute nontraumatic adult knee pain: the role of MR imaging

Acute nontraumatic pain in the adult knee can be seen in many settings, such as transient bone marrow oedema syndrome (TBMOS), regional migratory osteoporosis (RMO), spontaneous osteonecrosis (SONK) and insufficiency fractures. Early differentiation among them is crucial to avoid unnecessary treatment. TBMOS and RMO are considered to be self-limiting conditions without longterm sequelae. On the other hand, the clinical course of SONK is thought to be dependent on the size of osteonecrosis. Recent data suggest the term SONK is misleading one and should be replaced. Insufficiency fractures may demonstrate a similar clinical syndrome without a history of a single traumatic injury. The imaging pathway for knee pain has evolved considerably with the advent of magnetic resonance (MR) imaging, which is very sensitive in the early depiction of bone marrow oedema. Therefore, in patients with acute nontraumatic knee pain whose radiographs are negative or inconclusive, MR imaging is the method of choice for further evaluation. This article discusses the potential aetiologies and reviews MR imaging findings of the most common disorders afflicting the subchondral knee-joint area.     

MR imaging: its role in detecting occult fractures

Magnetic resonance (MR) studies were performed on 30 consecutive patients who continued to be symptomatic despite negative or inconclusive findings on radiographs and other imaging studies including radionuclide bone scans, computed tomography, and/or polytomography. There were 9 men and 21 women, 20–92 years old (mean age 63 years) whose MR studies were done 3–72 h after frank trauma in 22 cases and in another 8 after 1–4 weeks of increasing pain subsequently attributed to trauma or unaccustomed effort. MR studies were performed using 0.5-T (Phillips) or 1.5-T (Phillips, GE) superconductive magnets. Results indicated that: (1) MR images allowed identification of acute fractures in an emergency room setting, as well as subtle subacute or chronic fractures in the context of strong clinical suspicions despite negative or inconclusive radiographs and other subsequently indecisive imaging studies. (2) MR imaging is the most sensitive way of documenting the earliest changes in traumatized osseous and soft tissue structures simultaneously.     

Adhesive capsulitis: role of MR imaging in differential diagnosis

The purpose of this study was to describe and characterize the MR imaging findings in a group of patients who underwent surgery for adhesive capsulitis. Twenty-four MR imaging studies in 24 consecutive patients with clinical evidence of adhesive capsulitis were performed prior to arthroscopic capsulotomy. There were 17 women and 7 men with a mean age of 53.5 years. Images were scrutinised for changes in the synovium particularly in the rotator interval, around the biceps anchor and axillary pouch. Intravenous gadolinium was given routinely. We also examined a control group of 22 patients who underwent the same MR imaging protocol after referral for rotator cuff pathology. Soft tissue density showing variable enhancement after gadolinium administration was visible in the rotator interval in 22 of 24 studies on MR imaging. Seventeen patients showed soft tissue density partially encasing the biceps anchor. Ten patients showed thickening and gadolinium enhancement of the axillary pouch. Three patients from the study cohort had partial tears of the supraspinatus tendon. All the patients subsequently had surgery which confirmed fibrovascular scar tissue in the rotator interval, around the biceps anchor and a variable degree of synovial inflammation of the glenohumeral capsule. Two patients from a control group with suspected rotator cuff pathology showed abnormal intensity in the rotator interval on MR imaging. Magnetic resonance imaging can identify changes in the shoulder joint that correspond to abnormalities seen at surgery. This may be useful for discriminating adhesive capsulitis from other causes of shoulder pain.     

Graves ophthalmopathy: role of MR imaging in radiation therapy

Twenty-three patients with Graves ophthalmopathy who underwent radiation therapy were monitored by means of magnetic resonance (MR) imaging. T2 relaxation times of extraocular muscles and orbital fat, areas of extraocular muscles, and degree of exophthalmos were measured by means of MR imaging at the beginning, at the end, and 3 months after completion of radiation therapy. As a result, patients with primarily elevated T2 times of extraocular muscles showed a better therapy response regarding muscle thickening than patients with primarily normal T2 times. Elevated T2 times, which probably represent acute inflammatory changes, were markedly decreased at the end of therapy. Therefore, quantitative MR imaging favors the choice of anti-inflammatory therapy regimens in patients with elevated T2 times of extraocular muscles. However, the clinical response (activity scores) to the low-dose treatment protocol that was used did not correlate well with primarily elevated T2 times. Furthermore, T2 times increased again after cessation of therapy. Whether a higher radiation dose or a different fractionation scheme leads to better results must be clarified by means of further study.     

Acute bone marrow edema of the hip: role of MR imaging

Acute bone marrow edema of the hip is a diagnostic challenge for both radiologists and clinicians. Marrow edema is often seen in patients with hip pain and restriction of motion. In patients with acute non-traumatic hip pain, whose radiographs are negative or inconclusive, MR imaging is the imaging study of choice. MR imaging is the most sensitive and specific imaging technique for detecting transient osteoporosis and osteonecrosis, as well as for detecting and staging fractures and microfractures. MR imaging is able to show marrow involvement in various inflammatory disorders and to diagnose reactive marrow edema from femoroacetabular impingment and greater trochanteric pain syndrome. In patients with septic arthritis, it may also depict associated marrow edema and suggest its reactive or infectious origin. For the neoplastic disorders, although plain radiographs should be the initial examination, MR imaging may follow for assessing extension to the surrounding soft tissues and/or associated pathologic fracture, facilitating thus the treatment planning. Computed tomography is more accurate compared with MR imaging in diagnosing intra-articular osteoid osteomas.     

Deep venous thrombosis of extremities: role of MR imaging in the diagnosis

Current noninvasive imaging techniques for diagnosis of deep venous thrombosis (DVT) of extremities are limited in their ability to demonstrate central vein involvement and to distinguish acute from chronic changes. The utility of spin-echo magnetic resonance (MR) imaging for DVT was evaluated in 100 patients suspected of having either upper- (n = 25) or lower-extremity (n = 75) DVT. Ninety-seven patients were imaged successfully. In a subset of 36 patients, prospective comparison of MR imaging with contrast venography revealed a sensitivity of 90%, specificity of 100%, and Kappa level of agreement of .752 (P less than .0001). MR imaging showed more central extent of thrombus than did venography in all five patients with upper-extremity DVT and in 13 of 25 patients (52%) with lower-extremity DVT. Although all patients in the study were evaluated for acute symptoms, 13 of 59 (22%) MR imaging studies positive for DVT demonstrated chronic disease. MR images demonstrated ancillary abnormalities in 18 of 41 (44%) patients who did not have DVT. Thus, MR imaging has a role as the definitive examination when the results of initial screening studies are unsatisfactory, or as a first-line examination if (a) there is suspicion of upper-extremity or pelvic vein thrombosis, (b) there is a history of prior DVT that necessitates distinction of acute from chronic changes, or (c) other tests are unavailable.     

The role of MR imaging in scaphoid disorders

The scaphoid bone of the wrist is one of the most commonly fractured bones in the body. Due to its importance in the biomechanics and functionality of the wrist, it is important to depict and characterize the type of injury. Plain radiographs and scintigraphy may fail to disclose the type and severity of the injury. In patients with normal initial plain radiographs, MR imaging can discriminate occult fractures from bone bruises and may also demonstrate ligamentous disruption. MR imaging can also discriminate the proximal pole viability versus avascular necrosis secondary to previous fracture, which is important for treatment planning. Treatment of non-united fractures with vascularized grafts can be evaluated with contrast-enhanced MR imaging. Idiopathic osteonecrosis or Preiser’s disease was originally described after trauma. The non-traumatic disorders of the scaphoid include post-traumatic osteoarthritis, inflammatory bone marrow edema in patients with rheumatoid arthritis, and osteomyelitis. MR imaging is helpful in all the above disorders to demonstrate early bone marrow edema, cartilage degeneration and associated subchondral marrow changes. The most commonly found tumors in the scaphoid are usually benign and include enchondroma, osteoblastoma and osteoid osteoma. MR imaging is not mandatory for the initial diagnosis, which should be based on plain X-ray findings.