Hepatic angiosarcoma: mimicking of angioma on three-phase technetium-99m red blood cell scintigraphy.

A [99mTc]RBC study in a 63-yr-old man showed intrahepatic lesions which initially had less activity than surrounding liver tissue. When viewed 3 hr later, these had "reversed" and the lesions revealed increased uptake of the radiolabeled red cells. Some extrahepatic areas showed the same pattern (these were in the mesentery of the small bowel). The lesions proved to be angiosarcomas. Hence, the behavior of labeled red cells in these angiosarcomas mimicked that in benign hemangiomas.

Infrabladder "cup defect" following prostatectomy: recognition on bone scintigram.

Seventeen bone scintigrams, made after prostatectomy for proven or suspected carcinoma, showed a "cup defect" below the bladder. This defect was likely related to the volume of tissue removed at the time of transurethral prostatectomy. In two cases, the defect was not present on images made before prostatectomy but was clearly seen after the operation. The time of persistence of the "cup defect" is discussed, as well as the differential diagnosis of the finding.

Preleukemia following large dose radioiodide therapy for metastatic thyroid carcinoma.

A 67-yr-old woman had follicular thyroid carcinoma metastatic to several osseous sites. There was also evidence of functioning pulmonary metastases. She was treated by total thyroidectomy and multiple doses of radioiodide (131I). Approximately 2.5 yr after the initial ablative dose, and a total dose of 820 mCi of sodium iodide 131I, preleukemic changes were noted in the bone marrow. This appears to be the second case of preleukemia that bears a temporal relationship to radioiodide therapy of thyroid carcinoma, and the first in which radioiodide alone has been used in therapy (without additional external radiation).

Hepatic hot spot on both radiocolloid and hepatobiliary imaging in acute cholecystitis.

A focal hot spot in the liver, seen on radiocolloid imaging, has been reported in several conditions. A patient with acute cholecystitis who had a hot spot in the liver on both radiocolloid and hepatobiliary scintigraphy is described. The hepatobiliary finding disappeared following cholecystectomy.

Multiple bone metastases in a patient with glioblastoma multiforme.

Extracranial bone metastases from glioblastoma multiforme are rarely reported in the medical literature. The authors describe a case of glioblastoma multiforme with distant osseous metastases that were detected by a Tc-99m MDP image. The metastases were osteolytic and expansile on plain radiographs.

Pulmonary ventilation/perfusion and reverse mismatches in an infant.

A male infant, with bronchopulmonary dysplasia and ventilator dependence, had lung ventilation (Xe-133 gas) and perfusion (Tc-99m MAA) imaging performed. The examination revealed a region that was ventilated but not perfused (mismatch) and a separate area that was perfused but not ventilated (reverse mismatch). The basis of both abnormalities is suspected to be related to bronchopulmonary dysplasia, atelectasis and/or mechanical ventilation. Ventilation/perfusion mismatches and reverse mismatches can occur in the same patient.

Bone imaging in the diagnosis of fractures of the femur and pelvis in the sixth to tenth decades.

A review was made of the records of 24 consecutive trauma patients (aged 55-94 years) who had under gone radiographic examinations and a positive bone image of the femur or pelvis. There was considerable discordance between the radiographs and the bone images. Initially, 25% of the radiographs were interpreted as positive. Even after additional radiographs and retrospective. review, only 38% of the x-ray studies were positive. Bone imaging was a useful adjunct in these patients, both to confirm or exclude suspected fractures and to detect occult fractures. The necessity of delaying bone imaging for several days after the trauma was discussed.

Liver function tests. A study in patients with imaging-demonstrated metastases.

Thirty-eight consecutive patients with liver scan evidence of hepatic metastases (and confirmation by other modalities) had blood levels of lactate dehydrogenase and alkaline phosphatase performed within two weeks. In 38% of the patients with small liver metastases, both alkaline phosphatase and lactate dehydrogenase were in the normal range. Even with large metastases present (one or more lesions over 2.5 cm in diameter), 19% of the patients had both enzyme tests within the normal range. Despite the lower cost of these enzyme assays, they failed to detect hepatic metastases in an appreciable portion of our patients.

Technetium-99m MDP demonstration of neoplastic lesions involving bone and adjacent soft tissue.

Four patients are presented with malignant tumors involving both bone and adjacent soft tissue. In each of these neoplasms (two representing adenocarcinoma of the prostate, and one each of squamous cell carcinoma of lung and chondrosarcoma), the lesions were detected by accumulation of Tc-99m MDP. Involvement of both bone and soft tissue was confirmed by CT examination or surgery. It is probable that the lesions originated in bone and then extended to soft tissue.

Splenectomy for splenic metastasis from carcinoma of colon.

An 81-year-old woman with carcinoma of the colon had a normal liver-spleen radiocolloid image at the time of surgery. Two years later, a defect was noted in the spleen on a follow-up radiocolloid study. A repeat examination showed that the mass was increasing in size. An abdominal CT examination also revealed an intrasplenic mass with spring of the liver. After splenectomy for a metastatic carcinoma of the colon, the patient has survived for over a year without symptoms referable to tumor spread. Mention is made of the apparent splenic "immunity" from metastases.

Delayed accumulation (flip flop) of Tc-99m DTPA in a leiomyosarcoma.

An 85-year-old woman with leiomyosarcoma occupying the abdominopelvic area had a renal dynamic study with Tc-99m DTPA. The tumor area initially showed almost no content of the radiopharmaceutical. At 24 hours, there was retention of activity in the leiomyosarcoma as compared with surrounding tissues (flip flop). It was noted that, based on literature reports, tumors of mesodermal origin (leiomyoma, spindle cell sarcoma, neurofibroma) may have the ability to concentrate Tc-99m DTPA.

Unusual scintigraphic findings in a case of treated monostotic Paget's disease.

A 72-year-old woman with Paget's disease underwent therapy with EHDP for 5 years. A Tc-99m MDP bone scan demonstrated an unusual image in the right femur. The upper one third of the femur was thickened, bowed, and had diffuse and mild uptake. This corresponded to radiographic findings of mixed or chronic Paget's disease. A long area of intense and homogenous uptake was found immediately distal, and with a sharp demarcation. Alterations typical of the lytic phase of Paget's disease were seen on radiographs. The overall lesion in this patient thus demonstrated two distinct patterns, both radiographically and on bone imaging. It is conjectural whether this was related to the chronic use of a diphosphonate in therapy.

Prolapse of the urinary bladder demonstrated on bone imaging.

A urinary bladder, not demonstrable in the pelvis during a bone scan, was noted to have prolapsed.

High incidence of gastric reflux during hepatobiliary imaging in pancreatitis.

A review of 100 consecutive hepatobiliary studies revealed eight cases in which there was prominent gastric reflux of the Tc-99m diisopropyl-IDA beginning 0.5 to 2.0 hours into the procedure. Five of these individuals had pancreatitis (four acute, one chronic). Hence, pancreatitis was involved in five out of eight of the studies with marked gastric reflux. A study of discharge records showed that a total of ten of the patients in this series had pancreatitis. Since only five showed prominent gastric reflux, the incidence was 50%. Other disorders accounted for the three remaining gastric reflux cases observed in 90 patients.

The "warm" sacroiliac joint. A finding in pelvic abscess.

Two patients with pain referable to the low back and sacroiliac regions had bone scans with similar findings. In each, one sacroiliac joint was "warm" (uptake on that side was slightly greater than that in the contralateral area). Ga-67 imaging also demonstrated increased uptake in the same locale. Subsequent CT scanning revealed pelvic abscesses adjacent to the affected joints. Asymmetric uptake of bone imaging agent may have been related to hyperemia and "heating" of the sacroiliac joint. Rapid defervescence with antibiotics and drainage (and no CT evidence of bone involvement) suggested that osteomyelitis was not involved in these cases.

Meckel's diverticulum. Internal hernia and adhesions without gastrointestinal bleeding--ultrasound and scintigraphic findings.

The results from an ultrasound study performed on an 11-year-old boy, who had several weeks of intermittent abdominal pain, showed a nonperistaltic loop of bowel near the umbilicus, which suggested either an internal hernia or a diverticulum. Tc-99m pertechnetate imaging showed a focal collection near the umbilicus, which was consistent with a Meckel's diverticulum. No evidence was found of gastrointestinal bleeding. Exploratory laparotomy showed a Meckel's diverticulum near the terminal ileum and attached to the anterior abdominal wall close to the umbilicus. Small bowel had herniated through the loop formed by the terminal ileum and the diverticulum.

Renocutaneous inflammatory tract shown during technetium-99m DTPA imaging.

During a Tc-99m DTPA study, activity simultaneously appeared in the kidneys and in a right lateral band. This was due to an inflammatory tract and not to urinary drainage.

Multifocal osteogenic sarcoma in the seventh decade.

A 64-year-old man with right knee pain had uptake of Tc-99m MDP in the area as well as in the greater trochanter. Both sites were shown to contain osteogenic sarcoma. There was resection of the bone. Eight months later, radiogallium uptake was avid in the nearby soft tissue, indicating tumor spread.

Radioisotope bone scanning in a case of sarcoidosis.

The application of radioisotope scanning to osseous involvement from systemic sarcoidosis has been infrequently described in the scientific literature. Most commonly, the small bones of the hands and feet are affected if sarcoidosis involves the skeleton. Nonetheless, there are also occasional manifestations of sarcoid in the skull, long bones, and vertebral bodies. This paper describes a case of sarcoid involving the lung parenchyma with multiple lesions in the skull and ribs demonstrated by bone scanning with Tc-99m MDP. Following treatment with steroids, the bone scan showed complete resolution of the rib lesions and almost complete resolution of the lesions in the calvarium.

False-positive spleen imaging. Splenic cleft and accessory spleen.

Following trauma, a 35-year-old man had a falling hematocrit. Radiocolloid imaging showed a superior pole splenic defect with a bilobed appearance (suggesting nearly complete trans-section). There was a small quantity of function below the main portion of the spleen. At surgery, the spleen was noted to have marked lobulation (perhaps congenital) to account for the upper pole defect and trans-splenic appearance of a tear. A small accessory spleen was present below the main organ, mimicking the appearance of organ disruption. Cases of false-positive radiocolloid images, suggesting trauma, are rare but do occur.