Biomedical subjects
Publications and source records attributed to H J Steinkamp.
A case of a carcinoma-in-situ developing in a lateral cervical cyst (branchiogenic carcinoma) is described and compared with metastatic cervical lymph nodes (due to cancers from unknown primary sites). The authors are convinced that branchial carcinomas do exist, but are extremely rare. The available literature is reviewed.
In this prospective study 45 patients with cervical lymphadenopathy treated by operation, radiation and/or chemotherapy were examined by color-duplex sonography. The aim was to investigate the lymph node perfusion and to find out whether differentiation between benign and malignant nodal disease after therapy was possible by resistance and pulsatility indices. In 200 of 245 lymph nodes (82%) color-duplex sonography was able to detect perfusion. Using a pulsatility index (PI) threshold of 1.6 and resistance index (RI) threshold of 0.8, differentiation between reactive nodal enlargement and metastases was possible with an accuracy of 96%. Differentiation between lymphomas and metastases by RI and PI was not possible. Qualitative assessment of perfusional patterns was useful in detecting malignancy because reactively enlarged nodes showed greater hilar perfusion whereas metastases showed an increased peripheral perfusion. Lymphomas had both increased central and peripheral perfusions.
The value of magnetic resonance imaging (MRI) in preoperative tumor (T) staging was assessed prospectively in 46 patients with malignant carcinomas of the oropharynx and oral cavity. In each case, the MRI findings were compared with the preoperative clinical and postoperative histopathologic findings. MRI showed an accuracy of 89% in identifying the T stage, as compared with the histopathologic result. The accuracy of the clinical examination was 78%. Compared with the clinical examination, MRI is particularly suited for differentiating T3/T4 and the larger T2 tumors. MRI tends to overinterpret the T stage when the neighboring tissues are inflamed or edematous, as it allows no demarcation between inflamed or edematous tissue and tumor. Moreover, normal oropharyngeal mucous membrane and intrinsic tongue muscle both absorb contrast medium. In the clinical examination, the T stage is often underestimated, as the depth of infiltration and bone involvement cannot always be determined with certainty. The ability of MRI to give an axial, coronal, and sagittal image allows an exact preoperative view of tumor spread and assessment of infiltration into adjacent structures.
The ranking of postoperative sonography is examined in respect of imaging of neck lymph node enlargement and neck lymph node metastases or lymphomas, using a prospective study involving 119 patients whose head and neck tumours had already undergone treatment. These patients had been subjected to tumour aftercare for an average period of 26 months. The resulting quotient values (M/Q-Quotient) and the transverse and long axis lengths, respectively, were used as diagnostic criteria for suspicion of malignancy. A cervical lymph node with an M/Q-Quotient greater than two ruled out a metastasis with 94% accuracy. A quotient of less than two confirmed the presence of a metastasis with 92% accuracy. In comparison, evaluation using the transverse axis method ruled out metastasis in 92% of the cases, with a sensitivity of only 83%. The presence of sonomorphological criteria as a highly medullary reflex at the centre of the lymph node or excentric widening of cortex improves diagnostic safety.
This is the first study with high spatial resolution Magnetic Resonance Imaging (MRI), performed with a high resolution coil in a clinical whole-body system. Measurements were recorded with a slice thickness of 2 mm. A 256 x 256 matrix and a 2.5 cm field of view were used resulting in a pixel size of 0.01 mm2. MR images of the skin, hand, wrist, knee and ankle of 14 healthy volunteers, of three anatomic pathology tissue specimens and of three formalin-fixed specimens were obtained. Normal anatomy was identified and compared with the three gross anatomic pathology sections. The skin, hands, wrists and ankles of 30 patients were examined and a variety of pathological lesions were detected, including cutaneous neoplasms and ulceration, acute and chronic tendon lesions and pathologic features of the bone and wrist. Based on the excellent imaging of anatomic detail and superior contrast resolution, high resolution MRI proved an important complement for preoperative diagnosis.
Spiral CT was performed before treatment in 35 patients with suspected cervical lymph node enlargement. By coronary and sagittal reconstruction it is possible to utilise the M/Q quotient which has become accepted as the result of sonographic and MRI examinations. It is now possible to obtain high diagnostic accuracy (97%) for distinguishing between reactive change from metastatic infiltration of lymph nodes (> 8 mm) by using CT. Using spiral CT with 5 mm table movement, three patients diagnosed as stage N1 by axial CT were shown to be N2b. This represents a highly sensitive and highly specific method of lymph node diagnosis. Further diagnostic improvement derives from the ability to relate the lymph nodes to surrounding tissues. Spiral CT is also suitable for defining other space occupying lesions, e.g., the exact extent of retropharyngeal abscesses, abnormalities of the salivary glands or laryngoceles.
55 patients with cervical lymph node enlargement were studied prospectively by colour coded duplex sonography. The aim was to demonstrate the perfusion of individual lymph nodes and to determine whether the resistance and pulsatile index are able to show the cause of the enlargement. The lymph nodes were subsequently examined histologically. Useful perfusion measurements were obtained in 177 lymph nodes out of 216. Perfusion index < 1.6 and resistance index < 0.8 distinguishes between reactive lymph node enlargement and lymph node metastases with an accuracy of 91%. Reliable differentiation between lymphoma and metastases was not possible. Tuberculous lymph nodes and cysts showed significantly reduced resistance and pulsatile index when compared with metastases. Further information on the type of disease was obtained from the perfusion patterns. Reactive lymph nodes showed increased central perfusion of the hilum, whereas metastases tended to show increased peripheral perfusion.
PURPOSE: To evaluate criteria for differentiating malignant versus reactive lymph nodes in the head and neck on the basis of findings at helical computed tomography (CT). MATERIALS AND METHODS: Helical CT scans were evaluated of 70 consecutive patients (46 men and 24 women, aged 20-78 years [mean, 51 years]) with known head and neck tumors and cervical lymph node enlargement. The ratio of the maximal longitudinal to the maximal axial diameter (L/T) was calculated for nodes larger than 8 mm in diameter based on measurements obtained from coronal, paraxial, and sagittal reconstructions. RESULTS: At histologic examination, 96 of 164 nodes were malignant. Of these, 94 of 96 nodes had an L/T of less than 2 (sensitivity, 97%; specificity, 97%; accuracy, 97% for malignancy). Minimal diameter was more than 8 mm in 83 of 96 nodes (sensitivity, 87%; specificity, 89%; accuracy, 88% for malignancy). Low-attenuation centers and rim enhancement were seen in 75 of 96 nodes (sensitivity, 78%; specificity, 100%; accuracy, 86% for malignancy). CONCLUSION: The L/T at helical CT provide an accurate assessment of reactive versus malignant nodes in the head and neck.
In 32 patients suffering from cervical lymph node metastases with an unknown primary tumour the pretherapeutic findings via sonography, CT and MR were compared and the post-therapy findings of tumour aftercare assessed. After an average follow-up period of 38 months the group of branchiogenic cervical cysts had no recurrence. In the group of 18 patients with more than one cervical lymph node metastasis without primary tumour, either the primary tumour or further lymph node metastases became manifest in 11 patients after an average follow-up period of 36 months. Imaging of the number of lymph node metastases and differentiation between malignant degenerated branchiogenic cysts and lymph node metastases without primary tumour is important for prognosis. A combination of findings from sonography, CT and MR enables performance of such differential diagnosis due to morphological aspects and aspects that are conditioned by the contrast medium.
Spiral CT examinations were performed pretherapeutically in 27 patients in whom cervical lymph node enlargement had been suspected. The M/Q quotient known from sonography and MR can also be employed in CT by means of coronary and sagittal reconstruction. This improves CT differentiation between reactively changed and metastatically infiltrated lymph nodes in tumour patients. Hence, CT diagnosis can now make use of a highly sensitive and highly specific criterion for diagnosing lymph nodes. Another diagnostic improvement is that vascular infiltrations by lymph node metastases can now be visualised or excluded more readily. Spiral CT is also suitable in tumorous and non-tumorous processes for an accurate assessment of the extension of e.g. retropharyngeal abscesses or laryngoceles.
The ranking of postoperative palpation and sonography is examined in respect of imaging of neck lymph node enlargement and neck lymph node metastases or lymphomas, using a prospective study involving 127 patients whose head and neck tumours had already undergone treatment. These patients had been subjected to tumour aftercare for an average period of 26 months. Sonography is well suited for detecting the presence of enlarged neck lymph nodes, the accuracy being 97.5%. In this study palpation was clearly less safely defined, the accuracy being only 85%. The following results were obtained in respect of the specific imaging of metastases: sensitivity of palpation (75%) is below that of sonography (M/Q ratio) (93%). In respect of specificity palpation also yielded poorer results than sonography (M/Q ratio 94%) because of the relatively high proportion of false positive palpations (17%). The reason for this is non-differentiation between reactively enlarged lymph nodes and lymph nodes metastases. The advantage of sonography vs palpation by using the M/Q ratio is therefore the accuracy of the findings (94% sonography, 81% palpation) and hence the clear reduction in false positive and false negative findings. Furthermore, sonography can image the exact relationship to surrounding tissue and especially the vessels. The drawback of sonography is that lymph nodes < 9 mm maximal diameter cannot be assessed with the safety and accuracy mentioned above. Sonomorphological criteria such as the central marrow reflex and a widened lymphatic node cortex enhance diagnostic safety of the sonographic expansion parameters to yield an assessment of tumour status.
43 patients with malignant tumours of the larynx or hypopharynx were examined by MRT and CT to compare their accuracy for T-staging. There was histological confirmation in all cases. Histological studies showed an accuracy in T-staging of 90% for MRT and 82% for CT. Differentiation between stages T2/T3 and T3/T4 is possible in most cases by either method. A source of error is the difficulty of differentiating oedema or inflammatory changes from tumour. This led to occasional overinterpretation of the T4 stage. Demonstration of cartilage involvement was easier with MRT (88%) than with CT (84%). The use of Gd-DTPA with T1 weighted and proton weighted sequences allows earlier diagnosis of cartilage invasion. Early cartilage involvement may be missed by CT when it is seen on MRT. In addition, the ability to produce coronal and sagittal images by MRT makes this superior to CT in judging tumour extension.
The present study deals with the value of CDS in liver transplantation. Between September 1988 and October 1991 CDS of hepatic vessels was carried out in 194 liver transplants. Flow direction and flow velocity in the portal vein could be demonstrated in 97%. Measurement of flow velocity indicates the extent of portal hypertension; this can be confirmed by determining flow direction in the splenic and superior mesenteric veins. In 47 of 179 patients venous collaterals were demonstrated and in 15 of 179 patients there was retrograde flow in the splenic vein. In 95% of patients CDS indicated flow direction in the hepatic artery and in 93% in the hepatic veins. Thrombosis of liver vessels (portal and hepatic veins) was demonstrated in 11 out of 13 patients by means of CDS.
3-D-Spiral-CT was performed in 2 patients with orbita tumors with intracranic portion. 3-D-CT is enable to visualize the bony connections and judgement of bony destruction. Because of methodical parameters 2D-CT must be the basic of clinical diagnostic.
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30 patients with malignant tumours of the cavum oris and oropharynx were examined by MRI and CT to compare their accuracy for T-staging. There was histological information in all cases. Histological studies showed an accuracy in T-staging of 81% for MRI and 77% for CT. Differentiation between stages T2/T3 and T3/T4 is possible in 80% by CT and 84% by MRI. Tumours of the cavum oris and oropharynx of T1-stage are possible only in 1 of 3 cases. The use of T2-weighted sequences allows the best frequence of tumour representation in 89%. CT shows an earlier bone involvement than MRI. In addition, the ability to produce coronal and sagittal images by MRI makes it superior to CT in judging tumour extension.
In 51 patients with cervical swellings, pretherapeutic examinations by ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI) were carried out for the confirmation of exclusion of cervical lymph node metastases. By use of the M/Q ratio and morphological criteria, it is possible with ultrasound to differentiate between relatively enlarged lymph modes and lymph node metastasis with a certainly of > 90%. This was only possible in CT after administration of contrast media and the success rate was lower (72%). Both by use of the M/Q ratio and contrast medium administration, MRI is able to distinguish between lymph node metastases and reactively altered lymph nodes. Differentiation between Hodgkin/non-Hodgkin lymphomas of the neck and reactively enlarged lymph nodes is also possible with the aid of the M/Q ratio. In such cases, sonography and MRI are superior to CT. A certain differentiation between lymph node metastases and Hodgkin/non-Hodgkin lymphomas is only possible in some cases. However, there are indicative criteria for differential diagnosis. A delineation between specific lymph node inflammations and glomus carotid tumors is also possible because of the differing take-up of contrast medium in CT and MRI and via doppler sonographic criteria.
A total of 44 patients were evaluated to compare the value of B-mode sonography, Doppler sonography and colour coded Doppler sonography. All patients were studied because of suspected lesions of the femoral arteries following diagnostic and/or therapeutic cardiac catheterisation. B-mode sonography was unable to reliably differentiate between haematoma and pseudo-aneurysms, a.v.-fistula or combined lesions. Colour coded Doppler sonography can better demonstrate haematoma and thrombi in pseudo-aneurysms. The neck of a pseudoaneurysm can be exactly depicted by colour coded Doppler sonography. A.v.-fistula is shown by colour coded Doppler sonography based on typical colour coding and the Doppler spectrum. Combined lesions of pseudo-aneurysm and a.v.-fistula cannot reliably be detected by colour coded Doppler sonography, duplex sonography and B-mode sonography.