启发式教学法在医学影像学教学中的正确运用

现代医学影像技术发展迅速,各种新知识、新理论、新设备、新技术在医学影像领域层出不穷,它在某意义上代表着医学发展潮流中的一个热点,推动了医学的发展和诊治水平的提升[1],使各医院对医学影像人才的需求不断增大,对他们的影像综合应用能力要求进一步提高。如何在实际的教学过程中,解决由于影像课程中初始就是枯燥的解剖、病理、影像征象,难学费解,抽象性强,

Imaging of the Extra-axial Tumors and Tumor-like Lesions Involving both Middle and Posterior Cranial Fossae: Classification and Diagnosis

Objective: To study the imaging features of extra-axial tumors and tumor-likelesions involving both middle and posterior cranial fossae and to make a classification. Methods:Sixty cases of pathologically confirmed extra-axil tumors and tumor-like lesions involving bothmiddle and posterior cranial fossae were analyzed. They were divided into central and lateral types,the latter of which were subdivided into three types: middle cranial fossae type, posterior cranialfossae type and the over-riding type. The constitution and imaging features of each type wereanalyzed. Results: There were 12 cases of central type, including chordoma (n=5), pituitary adenoma(n=3), nasopharyngeal carcinoma (n=2), craniopharyn-gioma (n=1) and meningioma (n=l). 48 cases oflateral type including trigeminal nerve tumors (n=14), meningioma (n=12), epidermoid cyst (n=11),dural cavernous hemangioma (n=4), dermoid cyst (n=2), metastasis (n=2), hemangiopericytoma (n=1),paraganglioma of glonius jugular (n=1) and nasopharyngeal carcinoma (n=1). Each type of the lesionshad its own shape features, some of which were characteristic for some specific tumors. Most of thetumors and tumor-like lesions could be qualitatively diagnosed according to their imagingcharacteristics and the extent of the lesions could be defined definitely. Conclusion: It is helpfulto categorize extra-axial tumors and tumor-like lesions involving both middle and posterior cranialfossae according to their location for qualitative diagnosis and description of the extent of theselesions. It is of great clinical value in providing more precise and thorough imaging informationfor planning therapeutic methods and route of operation.

Endosonography with linear array instead of endoscopic retrograde cholangiography as the diagnostic tool in patients with moderate suspicion of common bile duct stones

AIM: To evaluate the diagnostic efficiency of endoscopic ultrasound (EUS) as the main imaging modality in patients with moderate suspicion of common bile duct stones (CBDS).METHODS: 55 patients with moderate clinical suspicion of CBDS were prospectively included to the study and evaluated with EUS. This study was done in single blind method in the clinical and biochemical data of patients. EUS was done with echo-endoscope Pentax FG 32-UA (f=5-7,5 MHz) and Hitachi EUB 405 ultrasound machine. Patients diagnosed with CBDS by EUS were excluded from this study and treated with ERC. All the other patients were included to the follow up study obtained by mail every 6 months for clinical evaluation (need of ERC or surgery).RESULTS: CBDS was found in 4 patients by EUS. Diagnosis was confirmed in all cases on ERC. The remaining 51 patients without CBDS on EUS were followed up for 6-26 months (meanly 13 months) There were: 40 women, 42cholecystectomized patients, aged: 55 (mean). Biochemical values (mean values) were as follows: bilirubin: 14,9 μmol.L-1,alkaline phosphatase: 95 IU.L-,1 γ-GTP: 131 IU.L-1, ALT: 50IU.L-1, AST: 49 IU.L-1, Only 1 patient was lost for follow up.In the remaining 50 patients with follow up, there was only 1 (2 %) patient with persistent biliary symptoms in whom CBDS was finally diagnosed by ERC with ES. All other patients remained symptoms free on follow up and did not require ERC or biliary surgery.CONCLUSION: Vast majority of patients with moderate suspicion of CBDS and no stones on EUS with linear array can avoid invasive evaluation of biliary tree with ERC.

Primary gastric lymphoma

AIM:The purpose of this review is to describe the various aspects of primary gastric lymphoma and the treatment options currently available. METHODS:After a systematic search of Pubmed,Medscape and MDconsult,we reviewed and retrieved literature regarding gastric lymphoma. RESULTS:Primary gastric lymphoma is rare however,the incidence of this malignancy is increasing.Chronic gastritis secondary to Helicobacter pylori (H pylori) infection has been considered a major predisposing factor for MALT lymphoma. Immune histochemical marker studies and molecular biology utilizing polymerase chain reaction have facilitated appropriate diagnosis and abolished the need for diagnostic surgical resection.Advances in imaging techniques including Magnetic Resonance Imaging (MRI) and Endoscopic Ultrasonography (EUS) have helped evaluation of tumor extension and invasion. The clinical course and prognosis of this disease is dependent on histopathological sub-type and stage at the time of diagnosis.Controversy remains regarding the best treatment for early stages of this disease.Chemotherapy,surgery and combination have been studied and shared almost comparable results with survival rate of 70-90%.However,chemotherapy possesses the advantage of preserving gastric anatomy. Radiotherapy alone has been tried and showed good results. Stage IIIE,IVE disease treatment is solely by chemotherapy and surgical resection has been a remote consideration. CONCLUSION:We conclude that methods of diagnosis and staging of the primary gastric lymphoma have dramatically improved.The modalities of treatment are many and probably chemotherapy is superior because of high success rate, preservation of stomach and tolerable complications.

Imaging diagnosis of colorectal liver metastases

Rapid advances in imaging technology have improved the detection, characterization and staging of colorectal liver metastases. Multi-modality imaging approach is usually the more useful in diagnosis colorectal liver metastases. It is well established that hepatic resection improves the long-term prognosis of many patients with liver metastases. However, incomplete resection does not prolong survival, so knowledge of the exact extent of intra-hepatic disease is crucially important in determining patient management and outcome. The diagnosis of liver metastases relies first and totally on imaging to decide which patients may be surgical candidates. This review will discuss the imaging options and their appropriate indications. Imaging and evaluating of colorectal liver metastases （CRLM） have been performed with contrast-enhanced ultrasound, multidetector computed tomography, magnetic resonance imaging （MRI） with extra-cellular contrast media and liver-specific contrast media MRI, and positron emission tomography/computed tomography. This review

Idiopathic sclerosing encapsulating peritonitis:Abdominal cocoon

Abdominal cocoon,the idiopathic form of sclerosing encapsulating peritonitis,is a rare condition of unknown etiology that results in an intestinal obstruction due to total or partial encapsulation of the small bowel by a f ibrocollagenous membrane.Preoperative diagnosis requires a high index of clinical suspicion.The early clinical features are nonspecif ic,are often not recognized and it is diff icult to make a def inite pre-operative diagnosis.Clinical suspicion may be generated by the recurrent episodes of small intestinal obstruction combined with relevant imaging f indings and lack of other plausible etiologies.The radiological diagnosis of abdominal cocoon may now be conf idently made on computed tomography scan.Surgery is important in the management of this disease.Careful dissection and excision of the thick sac with the release of the small intestine leads to complete recovery in the vast majority of cases.

Values of high-resolution computed tomography and pulmonary function tests in managements of patients with chronic hepatitis C virus infection

AIM:To investigate pulmonary involvement via pulmonary function tests (PFT) and high-resolution computed tomocjraphy (HRCT) in patients with chronic hepatitis C virus (HCV) infection. METHODS:Thirty-four patients with chronic HCV infection without diagnosis of any pulmonary diseases and 10 healthy cases were enrolled in the study,PFT and HRCT were performed in all cases. RESULTS:A decrease lower than 80% of the predicted value was detected in vital capacity in 9/34 patients,in forced expiratory volume in one second in 8/34 patients,and in forced expiratory flow 25-75 in 15/34 patients,respectively.Carbon monoxide diffusing capacity (DLCO) was decreased in 26/34 patients.Findings of interstitial pulmonary involvement were detected in the HRCT of 16/34 patients.Significant difference was found between controls and patients with HCV infection in findings of HRCT (X^2=4.7,P=0.003).Knodell histological activity index (KHAI) of 28/34 patients in whom liver biopsy was applied was 9.0±4.7.HRCT findings,PFT values and DLCO were not affected by KHAI in patients with HCV infection.In these patients,all the parameters were related with age. CONCLUSION:We suggest that chronic hepatitis C virus infection may cause pulmonary interstitial involvement without evident respiratory symptoms.

Diagnosis of carotid body tumor by digital subtraction angiography

Objective: To make a further understanding of the features of the carotid body tumor (CBT) by digital subtraction angiography (DSA) so as to explore the clinical value of DSA diagnosis and interventional therapy for CBT. Methods: DSA data from 12 cases of CBT were analyzed retrospectively. A consensus interpretation of the DSA appearances in all of the patients was reached after dynamic observation by 2 experienced radiologists in a double blind manner. Results: Definite diagnosis in all cases could be made by DSA. The DSA features of the CBT included bigger bifurcation angles of the internal and external carotid arteries, displacement of internal and external carotid arteries, CBT supplied by external carotid arteries in most cases and the significant increase of tumor blood vessels in bifurcation. Invasion of internal or external carotid arteries was found in 6 cases. Smaller stained area of the tumor and significantly reduced intraoperative bleeding were found after embolization of the supplying arteria in 2 cases. Conclusion: DSA is the effective method for the diagnosis and preoperative assessment of CBT. Preoperative embolization of CBT may contribute to the reduced intraoperative bleeding.

CT and MR imaging of Spongiform leukoencephalopathy after heroin vapor inhalation: analysis of 13 cases

Objective: To study the CT and MR imaging features of spongiform leukoencephalopathy after heroin vapor inhalation. Method,: The CT and MR imaging features and pathologic findings of 13 patients with heroin-induced spongiform leukoencephalopathy were analyzed. Results: CT scanning and MRI of all the patients showed diffuse, symmetric lesion in the cerebellar and cerebral white matter, and the cerebellum was invariably involved in all cases. Symmetric round or butterfly-like lesions lateral to the midline of the cerebellum with clear border was the most distinct feature in CT and MRI examination. The lesions were not found in the anterior limbs of the internal capsules. CT scanning showed low-density changes while MRI TIWI imaging presented low-signal and T2WI high-signal lesions without space-occupying mass. The pathologic findings showed spongiform degeneration of the white matter in the central nervous system, but necrotic lesions were not observed. Conclusions: Spongiform leukoencephalopathy should be considered when acute. cerebellar signs are present in patients who admitted a history of heroin inhalation. The CT and MRI manifestation of this disease is typical and the diagnosis can thus be made.

DIAGNOSIS AND TREATMENT OF THE PITUITARY METASTASES

Three cases of pituitary metastases were reported. They all had operations and the pathological exami-nation confirming the diagnosis. The clinical features of diabetes insipidus and extraocular nerve palsy were presented. In two cases, the original tumors were bronchioloalveolar carcinoma; in the other one, the original tumor was unknown. All three cases had poor outcome. These cases illustrate the fact that a pituitary metastasis can closely mimic a pituitary benign tumor, such as pituitary adenoma. Especially in the presence of suggestive symptoms such as diabetes insipidus and/or cranical nerve paralysis, the possibility of metastatic disease in the differential diagnosis of a pituitary mass should always be considered.

Mammographic features of breast cancer: Analysis of 118 cases

Objective: The aim of this retrospective study was to evaluate the mammographic imaging features (markers) on different types of breast cancer and improve early radiological diagnosis of breast cancer. Methods: Analyzed the mammographic images of 118 patients with breast cancer confirmed by surgery and pathology. Among 118 cases, 70 cases were infiltrating ductal carcinoma (59.3%), 17 cases were ductal carcinoma in situ (DCIS, 14.4%), 7 cases were mucinous carcinoma (5.9%), 5 cases were medullary carcinoma (4.2%), 1 case was tiny micro carcinoma (0.9%) and 18 cases were other types cancer (15.3%). Results: The mammographic appearance of 118 patients with different breast cancer included: tumor mass (n = 80, 68.8%), microcalcification (n = 57, 48.3%), which were subdivided into two groups (a) microcalcification only, 13 cases (13/118, 11%); (b) combined with other mammographic features: 31 cases with tumor mass (31/118, 26.3%); 7 cases with architecture distortion (7/118, 5.9%), 6 cases with focal asymmetric density (6/118, 5.1%). Six cases appeared as architecture distortion only, 41 cases with abnormal vessel signs (34.7%). Conclusion: The microcalcifications are the most frequently basal X-ray signs in DCIS. Architecture distortion and focal asymmetric density are special X-ray signs that were easily missed. The abnormal vessels are also important accompaniment signs of breast cancer. The use of coned compression technique is particularly important to improve the radiological diagnosis of breast cancer.

Value of CT scan in the diagnosis of primary large bowel lymphoma

Objective: To study the CT imaging of primary large bowel lymphoma and evaluate the value of CT scan. Methods: CT reports of 8 patients with proven primary large bowel lymphoma were retrospectively reviewed. Plain CT scans were done on all patients, enhanced CT scans simultaneously with 5-10 mm section thickness, and 5-10 mm table increments in 6 cases. Results: Primary involved sites were on the cecum (n=3), the ascending colon (n=2), and the rectum (n=1). The tumor was found in multiple areas of the large bowel in 2 cases. CT appearance fell into 3 typical patterns in our study. The first was focal mass type in 2 cases, with one combined with intussusception and retroperitoneal adenopathy; the second was segmental annular involvement type in 3 cases, with one of them combined with mesenteric adenopathy; the last was diffuse involvement type in 2 cases. Multiple nodules were seen in the rectum in 1 case. Conclusion: CT was found to be accurate in detecting the primary sites and complications of lymphoma, and evaluating invasion of adjacent structures; Focal mass type, segmental annular involvement type and diffuse involvement type are the main patterns of CT features in the primary large bowel lymphoma; The features revealed by CT scan are suggestive of primary large bowel lymphoma in some cases.

DIAGNOSIS AND TREATMENT OF MEDIASTINAL NEUROGENIC TUMORS--REPORT OF 110 CASES

Object.To study the clinical manifestations,diagnostic methods,surgical management ,and prognosis of various neurogenic mediastinal tumors.Method.One hundred and ten cases of neurogenic tumors of mediastinum were reviewed and retro-spectively analyzed.Results.Operative or hospitalization death happened in2cases,complications occurred in8cases,mostly were Horner’s syndrome or recurrent nerve paralysis.During the follow?up,there were2recur-rences in102benign tumors,and4cases of neurofibrosarcoma or malignant neurilemmoma died within3years postoperatively.Conclusion.Most mediastinal neurogenic tumors are benign.It is enough to establish diagnosis by chest X?ray and CT scan.There are different features in the clinical manifestations,diagnosing methods,and surgical management for the dumbbell tumors.Minimal invasive surgery and video?assisted thora-coscopy surgery(VATS)have a special value in treatment of the selected neurogenic mediastinal tumors.Benign neurogenic tumors rarely recur after complete resection,whereas malignant neurogenic tumors have poor prognosis.

ADRENAL INCIDENTALOMAS:ANALYSIS OF 126 CASES

Purpose.To evaluate the diagnosis and treatment of adrenal incidentalomas.Methods.One hundred and twenty-six patients with incidentalomas were analyzed,among them98underwent operation.Results.Eighty-eight of the adrenal incidentalomas were discovered by ultrasound.Of all the types of adrenal incidentalomas,52(41.3%)of them were adenomas;43(34.1%)were hypersecretory adrenal tumors,including29pheochromocytomas,9primary aldosteronisms ,1adrenogenitol syndrome combined with adrenal adenoma ,2Cushing’s syndrome combined with adenomas and2Cushing’s syndrome com-bined with nodular hyperplasias.All nonhypersecretory adrenal adenomas were under6cm,and all a-drenal carcinomas were above6cm.Conclusions.To search for hypersecretory adrenal tumors and to detect malignant adrenal tumors are quite essential in the process of diagnosing adrenal incidentalomas.For nonhypersecretory adrenal adeno-mas,the size of tumor is the most important index in determining whether the tumor is benign or malig-nant and whether the tumor needs to be treated with operation.

CT MANIFESTATIONS IN PULMONARY ALVEOLAR PROTEINOSIS AND COMPARED WITH CHEST RADIOGRAPHY(REPORT OF SIX CASES)

The CT including HRCT appearances of six patients with histopathologically confirmed pulmonary alveolar proteinosis(PAP) were evaluated and compared with those of chest radiographs In all patients the CT manifestations were quite similar: bilateral and diffuse airspace consolidation was usually patchy or confluent with sharply defined margins, intermingled with normal lung tissue The configuration of lung lesions was “geographical” in outline with angulate, strait and curved margins There were white branching linear opacities within the ground glass background Although various pulmonary diseases may mimic PAP in some way, a full awareness of the characteristic CT appearances of PAP is helpful in achieving a correct diagnosis CT may provide more accurate evidence than chest radiograph for the evaluation of the extent and delineation of PAP

DIAGNOSIS AND TREATMENT OF STAGE-ⅢPERIPHERAL SQUAMOUS CELL CARCINOMAOF RIGHT UPPER LUNG

During a 12-year period, 44 patients were surgically treated for stage- Ⅲ peripheral squamous cell car-cinoma of the right upper lobe. The mean time from the discovery of the shadow in the right upper lobe tothe confirmation of the diagnosis was 2 months. All patients underwent the resection of the right upperlobe with the dissection of the right mediastinal lymph nodes, among them, 4 patients had sleeve lobectomy of the right upper lobe. P-TNM staging: 23 cases were in stage- Ⅲ a, 21 cases in stage- Ⅲ b. The fre-quency of the postoperative complications was 20- 4 % (9/44 cases). The 1-year survival rate of all patientswas 61 % (27/44 cases). None of stage - Ⅲ b patients lived longer than 3 years. The postoperative 3-and 5-year survival rates of stage- Ⅲ a cases were 65. 2 % (15/23cases) and 21. 7 % (5/23 cases) respectively. Inthis article, the patients clinical features, the causes of delayed-diagnosis, the operative and postoperativemanagement were discussed. We suggest that the stage- Ⅲ a patients should be given surgical treatment,whereas, for the patients of stage- Ⅲ b, palliative operation was given just for the purpose of reliving thesymptoms.

Application of CT 3D reconstruction in diagnosing atlantoaxial subluxation

Objective:To evaluate and compare the diagnosti c value in atlantoaxial subluxation by CT three-dimensional (3D) reconstruction . Methods:3D reconstruction findings of 41 patients with atlanto axial subluxation were retrospectively analyzed, and comparisons were made among images of transverse section, multiplanar reformorting (MPR), surface shade dis play (SSD), maximum intensity project (MIP), and volume rendering (VR). Results:Of 41 patients with atlantoaxial subluxation, 31 belon ged to rotary dislocation, 5 antedislocation, and 5 hind dislocation. All the ca ses showed the dislocated joint panel of atlantoaxial articulation. Fifteen case s showed deviation of the odontoid process and 8 cases widened distance between the dens and anterior arch of the atlas. The dislocated joint panel of atlantoax ial articulation was more clearly seen with SSD-3D imaging than any other metho ds. Conclusions:Atlantoaxial subluxation can well be diagnosed by CT 3D reconstruction, in which SSD-3D imaging is optimal.

Traumatic endophthalmitis following penetrating ocular injuries with retained intraocular foreign bodies

Objective: To evaluate the outcome and analyze the methods of surgical treatment of traumatic endophthalmitis following penetrating eye injuries with retained eye foreign bodies. Methods: A total of 62 consecutive cases (58 men, 4 women) from January 1999 to December 2001 with IOFBs following penetrating eye injuries were retrospectively studied. The ages ranged from 8 to 46 years (mean 23 years). Sixty patients (63 eyes) underwent pars plana vitreotomy and 1 patient underwent external magnet extraction. The follow up ranged from 3 to 36 months (mean 12.5 months). Results: Ten eyes developed endophthalmitis, among which 7 ( 10.94 %) were diagnosed preoperatively. The most frequently cultured organism was Staphylococcus epidermis ( 44.44 %, 4/9). Postoperatively, retinal detachment due to vitreoretinal proliferation occurred in 5 patients with endophthalmitis and in 9 patients without endophthalmitis. All the retinal detachments were reattached with additional vitreoretinal surgery. Two eyes with endophthalmitis and two without endophthalmitis were eviscerated. Conclusions: Post traumatic endophthalmitis with intraocular foreign bodies (IOFBs) deserves great attention because of its high incidence and poor prognosis. Vitrectomy is suggested for the treatment of IOFBs and its complications, and it should be performed as soon as possible. Routine intravenous administration of antibiotics combined with periocular injection and topical antibiotics postoperatively are recommended.

The prospective study of the relationship between perimesencephalic cistern of CT scanning and the outcome of the patients with acute craniocerebral injury

Objective: To explore prospectively the relationship between the state of perimesencephalic cistern and the degree of deformation of the midbrain on CT scanning and the outcome of the patients with acute craniocerebral injury.Methods: The CT scan features including the states of perimesencephalic cisterns, the deformations of the midbrain and the ratios of the occipitofrontal diameter and the transverse diameter of the midbrain of 132 cases were measured. The GOS of the patients 3 months after trauma were regarded as outcome.Results: The rate of unfavorable outcome ( dead, vegetative status, severe disability ) was significantly correlated with perimesencephalic cistern narrower than 1mm (P < 0.05), especially narrower than 0.5 mm (P < 0.005), deformed midbrain (P< 0.005) or abnormal ratio ( < 0.9 or >.1) of the occipitofrontal diameter and transverse diameter of the midbrain (P < 0.01). But the patient's perimesencephalic cistern wider than 1mm and the patients without deformed midbrain got favorable outcome (moderate disability/good recovery).Conclusions: The state of the compressedperimesencephalic cistern ( < 1 mm) and the deformation of the midbrain may significantly indicate unfavorable outcome of the patients with acute craniocerebral injury.