Intraoperative scintigraphy in surgical treatment of thyroid carcinoma: evaluation of a new technique

Didactic review of 175 radionuclide-guided excisions of osteoid osteomas

The complete removal of a lesion which resembles, or is covered by adjacent tissue may be difficult. Therefore, the capacity of certain lesions to specifically concentrate a radiopharmaceutical has been used to orient progress during surgery. Usually, the measurements of radioactivity in the operative field are carried out by means of small, handy radiation-detecting probes which can be sterilized. "Intra-operative nuclear medicine" or "radionuclide-guided surgery" has steadily gained in importance. However, this technique is not being taught. Our study, based on radionuclide-guided surgery of 175 orthopaedic patients suspected of having osteoid osteoma, is well suited to teach the particularities of intra-operative radiation detection, as well as the collaboration between the nuclear physician and the surgeon in the operating theatre.

Peroperative (123)I-MIBG scan using a sterile probe for staging and resection of neuroblastoma in children

Two children with neuroblastoma were treated at Bristol Children's Hospital. One had primary resection of a right adrenal tumor; the other had resection of a secondary lymph node located in the left supraclavicular fossa. In both cases, the patients received 123(I)-meta-iodobenzylguanidine (MIBG) preoperatively, and a sterilizable, hand-held Cadmium-Telluride (CdTe) solid-state detector was used for localization of the tumor. The surgical procedure was facilitated significantly by this peroperative radioisotope-guided technique.

Postoperative radioactive iodine evaluation of total thyroidectomy for thyroid carcinoma: reappraisal and therapeutic implications

The records of 430 patients who underwent total thyroidectomy with radioactive iodine (RAI) uptake studies performed postoperatively were reviewed. Indications for the administration of an ablative dose of iodine 131 are given. The majority (85.4%) had no or low (less than 2%) evidence of focal uptake and therefore were not treated with ablative doses of iodine 131. RAI scanning is necessary postoperatively to determine the completeness of the surgical procedure and to detect residual or metastatic disease. Small foci of residual disease or occult distant metastases can be adequately treated with therapeutic doses of RAI. Nodal or distant metastases that become clinically evident following thyroidectomy are usually not successfully treated with RAI.

Intraoperative bone scintigraphy in orthopaedic surgery

A sterilisable radiation probe of small dimensions was designed to locate the lesions at orthopaedic surgical sites according to the procedure of intraoperative bone scintigraphy. The probe has a collimated opening 2 mm in diameter. It is connected to a portable radioactivity counter which converts the disintegration rates detected at surgical sites into an acoustic signal that increases steeply with increasing disintegration rate. The acoustic signal enables the surgeons and isotope specialists to readily monitor radioactivity in the region of interest without attention being distracted from the surgical site. Dimethylaminodiphosphonate (designated SF44) was the osteotropic radiopharmaceutical chosen for carrying out intraoperative bone scintigraphy, since the available data show that this chemical increases the pathological: normal bone uptake ratio of the lesion by 25% compared to the usual diphosphonates. Forty-seven orthopaedic interventions were carried out according to the intraoperative bone scintigraphy procedure. They showed that this procedure facilitated the rapid location of the lesion, the objective termination of the operation, less frequently the reduction in dimension of the excised areas, and rarely the simplification of the surgical technique. Practice of intraoperative bone scintigraphy requires proper training and caution.

The thyroid nodule. Diagnosis and surgical treatment

A definitive evaluation of different therapeutic approaches to patients with papillary and follicular thyroid carcinomas requires a prospective multicenter long-term study, with careful documentation of variations in histologic classification and all other factors that can possibly influence prognosis. Until such information is available, every patient with a thyroid nodule should be given the treatment that offers the best prospect for cure to the greatest possible number of patients; this treatment appears to be hemithyroidectomy for benign unilateral thyroid tumors and total thyroidectomy for carcinomas. These operations can be done safely by experienced surgeons without exceeding the morbidity or complication rate of less extensive treatments.