Bone and gallium scans in mastocytosis: correlation with count rates, radiography, and microscopy.

Mastocytosis (urticaria pigmentosa) was proven in a patient suffering from severe back pain. A bone scan showed diffusely increased bone activity. Count rates were also abnormally elevated over several areas of the skeleton. Radiographs were consistent with mastocytosis in bone.

The scintigraphic investigation of sacroiliac disease.

Bone scintigraphs obtained with both Technetium-99m polyphosphate and Technetium-99m pyrophosphate have been abnormal at the sacroiliac joints of 44 patients with definite ankylosing spondylitis (AS). Because of the normal registration of the sacroiliac joints on bone scintigraphy, it has been necessary to develop a profile-scan technique to quantify the abnormality that proves to be significantly different from the normal finding. In 17 patients with a strong clinical suspicion of AS but normal radiographs, the sacroiliac joints have frequently been abnormal. This finding is meaningful because there is a common occurence in this group of the histocompatibility antigen HL A-B27, known to be a marker of AS. We also note the frequency of abnormal sacroiliac scinitigrams in 26 patients with rheumatoid arthritis and in a group of other diseases-Crohn's disease, uveitis, psoriasis, ulcerative colitis, and Reiter's disease-all of which share some of the manifestations of AS.

Scintigraphic findings in ankylosing spondylitis.

A prospective study of bone scintigraphic findings has been carried out in 63 patients, firmly diagnosed as having ankylosing spondylitis. In addition to abnormal uptake of the radiotracer at the sacroiliac joints, a peripheral arthropathy has been a common finding, particularly in the proximal joints, occurring in up to 50% of patients. Increased uptake of radiotracer in the spine has also been found both diffusely and focally. Focal increases have been noted at the apophyseal joints in 40% of patients and in three patients with a sterile intervertebral diskitis, an unusual complication of this disease only diagnosed in two patients after bone scintigraphy.

Iatrogenic alterations in radionuclide biodistributions.

The biodistribution of radiotracers used in diagnostic imaging is grossly and recognizably altered by a wide variety of drugs and other treatment modalities, such as surgery and radiotherapy. Knowledge of such altered biodistribution is important both in making diagnostic inferences from scans and in dosimetric considerations.

Localization of gallium-67 citrate in salivary glands following radiation therapy.

Gallium-67 citrate was found to localize in the salivary glands of eight patients after therapeutic doses of radiation to a treatment field including the glands. In two patients, autopsy evidence to the effect that no primary disease was present to explain such uptake was obtained. In another two patients the abnormal uptake was not observed on follow-up. The recognition that radiation sialadenitis is a potential cause of false-positive gallium scintiscans is important in their interpretation.

Scintilymphangiography with 99 mTc-antimony sulfide colloid in hereditary lymphedema (Nonne-Milroy diseases).

A family of four patients suffering from Nonne-Milroy disease has been examined by pedal scintilymphangiography. Lower limb edema was present in three patients and was bilateral in two instances. Scintilymphangiographic abnormality was invariably present, ranging from almost total obstruction of lymphatic flow to lymphatic pooling. The inguinal, iliac and para-aortic nodes on the affected sides were also noted to be small and few in number. The examination is safe and simple and may be used to distinguish Nonne-Milroy edema from edema due to other causes.

Lymphocutaneous fistula following renal transplantation.

A patient is described in whom the postoperative management after renal transplantation was complicated by a wound discharge. A radionuclide technique of solving the clinical dilemma is discussed, using scintilymphangiography and qualitative assays.

Cystic thyroid mass following I-131 treatment of papillary thyroid carcinoma: an unusual complication.

Several unusual complications of I-131 therapy for thyroid carcinoma are known. Two patients who developed a further unusual event that consisted of a palpable mass and cystic degeneration are described.

Tc-99m HMPAO to demonstrate diffuse cortical necrosis in vivo.

Tc-99m hexamethylpropylene amineoxime (HMPAO) is a novel radiopharmaceutical demonstrated to be a sensitive indicator of abnormalities of cerebral perfusion. Most reports in the literature have evaluated patients with gross perfusion deficits, such as cerebrovascular accidents, and with dementia, where patterns of diffuse perfusion deficit were reported comparable with those seen in PET studies. We report a patient in whom there was the rapid onset of dementia, with the HMPAO images demonstrating diffuse loss of cortical perfusion in a nonfocal, and nonsegmental, fashion. Correlation with postmortem examination demonstrates good concordance between the diffuse nature of HMPAO loss, and diffuse cortical necrosis throughout both cerebral hemispheres. The technique was shown to be more sensitive than transmission CT scanning in demonstrating the extent of the deficit, and it correlated closely with the functional deficits noted in the patient.

Clinically and mammographically occult breast lesions demonstrated by ultrasound.

Histologic proof from 62 sites in 58 patients in whom an ultrasonic abnormality was detected in the absence of palpable or mammographic evidence revealed no malignancy. It is suggested that decision to biopsy be made on clinical grounds.

Multimodality detection of metastatic melanoma.

A retrospective evaluation of radionuclide liver and spleen scintigraphy (LS), ultrasonography (US), and computed tomography (CT) was performed in 88 patients who had pathologically proven cutaneous melanoma. In patients who had all three examinations (n = 24), the matrix analysis showed that CT was significantly more sensitive (0.94) in detecting intra-abdominal metastasis when compared to US (0.62, P less than 0.05) and LS (0.38, P less than 0.01). Sixty-four patients had only US and LS studies. In this group of patients US was found to be more sensitive than LS, 0.88 and 0.54 respectively (P less than 0.01). Furthermore, when CT was compared with US, CT was shown to detect metastases significantly earlier than US (P = 0.03). Overall, CT provided the most accurate means for detecting the intra-abdominal metastases of cutaneous melanoma.