Three dimensional solid model reconstruction for neurosurgical approach.

Two different types of solid models of neurosurgical pathologies by 3-D reconstruction were presented and examined, and their clinical usefulness was appraised by neurosurgical simulation. Cranial vessel models were proposed by solidifying liquid photopolymer based on 3-D MR angiography data. These models provided total visual and tactile perceptions of the anatomy. Aneurysm model well demonstrated the root of its origin and was useful in preoperative planning. Three dimensional demonstration of arterial angles gave more informations for performing transarterial embolization of aneurysm. This method had advantages in visualising more complicated or minute structures such as cerebral vessels. Intracranial pathologies and the skull base anatomy were demonstrated by milling urethane block based on CT data. These models were useful in deciding the appropriate direction of surgical approach for lesions located in the middle fossa. This method had another advantage to demonstrate the details of anatomical relationships between macroscopic pathologies and surrounding structures. Milled models were useful for the practice of preoperative simulation because urethane was easily processed in comparison with solidified polymer.

Carcinoma of the uterine cervix with myocardial metastasis.

Cardiac metastasis from pelvic malignancies is rare. We experienced a case of carcinoma of the uterine cervix with myocardial involvement in the right ventricle, and treated this patient with conventional methods until her death. The metastatic tumor was incidentally found in the right ventricle, eroding the myocardium. We used CT, MRI, and gallium scintigraphy to assess the lesion. This aggressive lesion proved fatal for our relatively young patient. We report this case for future reference.

[Three-dimensional longitudinal dissection view of hollow viscus].

To visualize the pathologies of hollow viscus and their extension three-dimensionally, volume data of the larynx, trachea, stomach, rectum, and urinary bladder were obtained using helical CT with moderately thin slices. Longitudinal cut sections were made as in a simulated surgical cut, and the interior morphology was displayed along with the pathology. A cylindrical projection profile was made by making a longitudinal incision on one wall and pulling apart the flaps to reveal the interior, providing better visual perception. The detailed outline from the 3D profile and the cylindrical projection views constituted an added advantage over the existing procedures.

Quantified application of MRI for diagnosis of head and neck tumors.

We evaluated T/M ratios and T2 values of 6 malignant lymphomas and 8 squamous cell carcinomas in the head and neck in order to differentiate these two entities. T/M ratios were calculated by dividing intensity of tumor by that of muscle in same slice images. T2 values were calculated from T2-weighted images and proton-weighted images. Statistical difference of T/M ratios was found between malignant lymphomas and squamous cell carcinomas, but no difference of T2 values was seen between two groups. T/M ratio was considered to be a useful and quantified index for evaluation of head and neck tumor.