Tc-99m sestamibi scintigraphy in multiple myeloma

Tc-99m sestamibi imaging was performed in two patients with multiple myeloma. Focal areas of increased uptake in one patient and diffuse skeletal uptake in the second patient were found. Tc-99m sestamibi appears to identify bone marrow and osteolytic involvement in multiple myeloma.     

Diagnosis of diabetic gastroparesis on Tc-99m hepatobiliary scintigraphy

Diabetic gastroparesis is a common problem in diabetics, especially insulin-dependent diabetics. The diagnosis usually is suggested on plain radiographs and confirmed on either upper gastrointestinal barium series or radionuclide gastric emptying studies. The clinical diagnosis is not always easy and some patients may present atypically with right upper quadrant pain simulating acute cholecystitis. In these patients, hepatobiliary scintigraphy may be the initial investigation performed and may first demonstrate unsuspected gastroparesis. Therefore, it is useful for the nuclear medicine physician to be aware of this entity to ensure early diagnosis and prompt treatment. The authors report one such case of diabetic gastroparesis that was diagnosed initially on a Tc-99m hepatobiliary scan.     

Diagnosis of orbital cavernous hemangioma with Tc-99m RBC SPECT

The authors report two cases of orbital cavernous hemangioma diagnosed by Tc-99m RBC SPECT. Tc-99m RBC SPECT showed a typical scintigraphic pattern commonly seen in hepatic hemangioma in which there is intense focally increased uptake on delayed SPECT images. Tc-99m RBC SPECT in orbital cavernous hemangioma may be as useful a diagnostic modality as in hepatic hemangioma.     

Double-phase Tc-99m sestamibi scintigraphy in the preoperative location of lesions causing hyperparathyroidism

The effects of mycotoxin citrinin on Ca2+ efflux and membrane permeabilization were studied in isolated rat liver mitochondria. The efflux rate observed when in presence of ruthenium red was higher when citrinin was added. Swelling experiments demonstrated Ca(2+)-dependent membrane permeabilization by citrinin. Catalase, butylhydroxitoluene (BHT), and dithiothreitol (DTT) did not protect swelling caused by Ca2+ plus citrinin. The protection conferred by ATP-Mg2+ and cyclosporin A in the latter experiments are strong indications of pore formation. These results suggest that citrinin can induce permeability transition by a mechanism that does not involve oxidative damage.     

Metastasis of hepatocellular carcinoma to the colon demonstrated by Tc-99m PMT scintigraphy

A 57-year-old man was found to have a tumor in the ascending colon after hepatic segmentectomy for ruptured hepatocellular carcinoma. Colonoscopy was performed, and metastasis of the hepatocellular carcinoma to the ascending colon was suspected based on the biopsy specimens obtained from the tumor. On hepatobiliary scintigraphy using Tc-99m PMT performed to confirm this diagnosis, Tc-99m PMT was clearly observed to accumulate in the tumor. Thus, the tumor was diagnosed as metastasis of hepatocellular carcinoma.     

Scintimammography using Tc-99m tetrofosmin

TIM (Zeppelin Chirurgische Instrumente GmbH, 82 049 Pullach, Germany) is a tomographic imaging system which enables surgeons to visualize the pathologic lesions three dimensionally in relationship to the surrounding structures. The distance and the angle between the pathologic lesion and the anatomical and/or bony landmarks as well as the volume of the mass lesion can be measured. Therefore an accurate localization of the lesion is possible with this technique. It is very applicable for planning of surgery on skull base tumors. The surgical procedure for small and well-defined, intrinsic pathologic deep-seated brain lesions, however, becomes much easier by using the stereotactic techniques of this system. The target point and the direction brain-surface-to-lesion can be determined within seconds. Before the aiming probe is inserted to the target, the cortical motor area is mapped by direct electrical stimulation. The approach can be varied depending on the results of these neurophysiologic investigations of the brain surface. The dissection is made along the aiming probe up to the target point. Because of the fixation of the brain with the needle, a brain shifting due to the dissection as well as to CSF release is diminished. Forty patients with deep-seated intracerebral lesions were operated on during a 13 months period by these combined techniques in our service. Using this technique, we never made a negative exploration. In all but three patients, total removal of the mass lesion was achieved. Permanent neurological deficits were observed in two patients only. In our opinion, this combined imaging and neurophysiological technique is easy to perform, and of major benefit for the patients due to its accuracy and is preferable in comparison with other single computer localizer techniques without neurophysiological monitoring.     

Increased bone marrow uptake on Tc-99m DMSA scintigraphy in a patient with renal osteodystrophy

Anxiogenic action of m-chlorophenylpiperazine (mCPP), a 5-HT1C receptor agonist, was studied in naive rats and in ethanol-tolerant rats following withdrawal from chronic ethanol administration. The purpose of this investigation was to determine whether a sensitization to mCPP develops during withdrawal from chronic ethanol. Male Long-Evans hooded rats were fed a liquid diet containing 4.5% ethanol or dextrin (as control) for four days. Twelve hours (acute withdrawal) or 4 days (protracted withdrawal) after the last dose of ethanol, rats were injected with saline or mCPP (0.08-5.0 mg/kg) and were tested in the elevated plus-maze 15 min postinjection. A reduction in percent open-arm activity, indicative of anxiogenic behavior, was observed in ethanol-treated rats injected with saline. Administration of mCPP further reduced the percent open-arm entries and time in ethanol-withdrawn rats. An eightfold reduction in maximum effective dose of mCPP was observed during acute ethanol withdrawal as compared to that in naive rats. During protracted ethanol withdrawal the maximum effective dose of mCPP was reduced by 75%. A shift of the mCPP dose-response curve to the left following withdrawal from chronic ethanol may indicate that 5-HT1C receptor sites are more sensitive to the activation by an agonist. This effect may be exploited in developing specific 5-HT1C receptor antagonists for the treatment of ethanol withdrawal symptoms.     

Detection of abscesses with Tc-99m HMPAO leukocyte scintigraphy depends on their stage and location

Two abscesses were shown on CT in a 72-year-old man: one in the left hip and one in the left pelvic region that resulted from a motor vehicle collision that occurred 8 months earlier. Bone scintigraphy showed increased uptake in the left hip area. On Tc-99m HMPAO leukocyte imaging, the hip area appeared to be photopenic, and the abscess of the left pelvis was not identified. Incidental uptake in the left lung base appeared to be an active acute inflammatory process as evidenced by an infiltrating lesion in the left lower lung on a chest radiograph. Because leukocyte scintigraphy cannot detect the presence of a chronic inflammatory process in the absence of acute inflammatory cells, the patient's abscesses in the left hip and the left pelvis did not localize Tc-99m HMPAO-labeled neutrophils. The cold lesion in the left hip area was most likely caused by the lesion in the reticuloendothelial system (bone marrow); the unidentifiable pelvic lesion was related to the area(s) outside the reticuloendothelial system. In interpreting a labeled leukocyte image, clinicians should be alert to the stage (chronic or acute) and location (regardless of whether in the reticuloendothelial system) of infectious lesion(s). In this patient, a wide spectrum of manifestations was evident on leukocyte scintigraphy.     

Discordant splenic uptake of Tc-99m colloid and Tc-99m denatured RBC in candidiasis-endocrinopathy syndrome

The aim of this study was to estimate the incidence of melanoma in the Paris region in 1994 and analyse the main clinical and histological characteristics of these lesions. It took the form of a prospective inquiry, mailed to public and private pathology laboratories, to count as accurately as possible the number of new cases diagnosed by pathologists in the region during the 1994 calendar year. In all, 1089 newly diagnosed Clark level I to V melanomas (excluding precancerous melanosis of Dubreuilh) were studied. Parameters recorded included age, sex, Clark level and Breslow's thickness. The incidence per 100,000 inhabitants was 9.93 for melanoma and 8.62 for invasive melanoma. The female to male ratio was 1.6. Clark level I or thin (< 0.75 mm) melanomas represented 64.8% of the lesions. At the time of diagnosis, the females were significantly younger than the males (P = 0.004). Breslow's thickness increased with age and was significantly lower in women (P = 0.00005), especially those between 40 and 49 years old. The incidence of melanoma in the Paris region in 1994 was close to that observed during the preceding 5 years in England, Scotland and the French department of Haut-Rhin. It was 2.32 times higher for males and 1.69 times higher for females than the rates estimated for France for the period 1978-1982.     

Contribution of hepatic scintigraphy with Tc99m blood cells to the imaging diagnosis of cavernous hemangioma. Results in 48 patients

Dividing the delivery system of larger psychiatric hospitals into defined smaller catchment areas called sectors, implies a contribution to quality assurance. Continuous monitoring and evaluation of a period before and after this reorganisation, which took place in 1994 for the central region of Zürich (Psychiatric University Hospital), allows perception of expected and possible unexpected changes. All newly registered patients were recorded within a time span divided into five periods of six month five each, the last one covering the first six months after sectorisation. This design permits to answer the question as to how fast the intended changes after sectorisation occur, and also to control side effects. Results show that sectorisation resulted in a marked increase of registrations from the defined catchment area of each sector, and that the investigated institutions achieve attainment of the aim to effect a special selection of psychiatric patients characterised by considerable psycho-social deficits. The two sectors display differences in respect of socio-demographic characteristics of newly registered patients.     

Tc-99m HMPAO cerebral scintigraphy. A reliable, noninvasive method for determination of brain death

To investigate the relationships between the mammographic aspects (according to Broberg), proliferative activity and hormone receptor status, we studied 165 patients subjected to radical mastectomy for operable breast cancer. The highest percentage of estrogen receptor-positive cases was observed in mammograph class I (p < 0.02) while classes III and V were highest in progesterone receptor-positive cases. Proliferative activity (111 cases) was significantly lower in class I and IV with respect to all other classes (p < 0.03 and p < 0.01, respectively). This study suggests that certain mammographic signs can be related to the biological characteristics of breast cancer.