Prenatal diagnosis of a fetal intracranial tumor

Cap polyposis is a rare intestinal disease that can be difficult to differentiate from inflammatory bowel disease. When cap polyposis is suspected, it is important to confirm protein loss. A 54-year-old woman who had been treated for ulcerative colitis for 7 years had severe hypoproteinemia. Scintigraphy with Tc-99m-labeled DTPA complexed with human serum albumin showed protein loss from the descending colon. Left hemicolectomy and sigmoid colectomy were performed. Cap polyposis was diagnosed on the basis of histologic findings from an operative specimen. The patient's diarrhea resolved after surgery and her hypoproteinemia improved. Scintigraphy with this label gave information helpful in the diagnosis of cap polyposis.     

The usefulness of Tc-99m HMPAO labeled WBC SPECT in eosinophilic gastroenteritis

Tc-99m HMPAO labeled WBC SPECT was performed in 5 patients with eosinophilic gastroenteritis before and after successful medical therapy. The imaging findings were graded according to the following imaging scheme; grade 0, no uptake; grade 1, uptake < bone marrow; grade 2, uptake < liver; grade 3, uptake > liver. In no patient was the diagnosis made radiologically or with colonoscopy. The sites of involvement were identified with Tc-99m HMPAO WBC imaging in all patients before treatment and the radionuclide imaging studies were all negative after therapy.     

Pelvic radiation therapy as a risk factor for ischemic colitis complicating abdominal aortic reconstruction

Ischemic colitis is an infrequent but potentially devastating complication of abdominal aortic reconstruction. Identification of patients with predisposing risk factors for the development of ischemic colitis can guide intraoperative measures to preserve or restore colonic blood flow during aortic surgery. Previous radiation therapy for pelvic malignancy may be one such predisposing risk factor. Two cases are presented in which ischemic colitis complicated abdominal aortic reconstruction in the setting of previous pelvic irradiation. In the months after radiation therapy for prostate cancer, one patient underwent infrarenal abdominal aortic aneurysm repair. Ischemic infarction of the sigmoid colon developed acutely after surgery and required emergent sigmoid colectomy. The second patient underwent reconstruction of an infrarenal abdominal aortic aneurysm after having had radiation therapy for a bladder tumor. Despite an initial satisfactory result, the patient's abdominal pain and diarrhea progressively worsened and he eventually required sigmoid colectomy for severe ischemic colitis. In both of these patients, the inferior mesenteric arteries were patent and had not been reimplanted. The association of pelvic radiation therapy with ischemic colitis after aortic reconstruction should focus attention to the operative details for maintaining the colonic circulation in these patients. Reimplantation of the inferior mesenteric artery in particular may prevent both the acute and the insidious variants of this complication in patients who undergo aortic surgery and decrease the incidence of this complication in patients with a history of radiation therapy to the pelvis.     

Viral encephalitis in children: detection with technetium-99m HMPAO brain single-photon emission CT and its value in prediction of outcome

PURPOSE: To assess the role of regional cerebral blood flow measured by technetium-99m hexamethyl propyleneamine oxime (HMPAO) brain single-photon emission CT (SPECT) in viral encephalitis of children. METHODS: Eighteen children diagnosed as having viral encephalitis (12 Epstein-Barr virus, 4 herpes simplex virus, and 2 Japanese B virus) underwent Tc-99m HMPAO brain SPECT and brain MR and/or CT. RESULTS: During the acute episode, 4 (22%) of the 18 patients had localized abnormality on brain MR and/or CT. Tc-99m HMPAO brain SPECT in the acute phase showed that 17 (94%) of the 18 patients had increased regional cerebral blood flow and 1 (6%) of the 18 children had a normal brain SPECT. Follow-up brain SPECT was performed at least 15 days after the acute episode. In 17 patients with abnormal first brain SPECT, 12 (71%) had normal second brain SPECT and 5 (29%) had decreased regional cerebral blood flow. The group of patients with normal regional cerebral blood flow on the follow-up brain SPECT had a better outcome than the group of patients with decreased regional cerebral blood flow. CONCLUSIONS: (a) The Tc-99m HMPAO brain SPECT was abnormal more often than CT or MR in children with acute viral encephalitis and provided better location. (b) In acute episodes of encephalitis, most patients showed locally increased regional cerebral blood flow. (c) After acute episodes, the regional cerebral blood flow returned to normal in most cases. (d) A normal Tc-99m HMPAO brain SPECT in the subacute phase usually indicates a good clinical outcome (no neurologic defect) 1 year after the acute illness in children with viral encephalitis.     

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.     

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.     

Gastric duplication-colonic fistula with colonic ulceration and bleeding

An 11-month-old girl had massive rectal bleeding. A midabdominal mass was palpated. Ultrasound scan showed a large cystic mass with diffusely echogenic contents; Tc-99M radionuclide scan confirmed a duplication. Exploratory surgery and pathology examination showed a gastric duplication with formation of a fistula into the transverse colon with a colonic ulcer and hemorrhage. This combination of findings is presented as a rare cause of lower gastrointestinal hemorrhage in infancy.     

Incremental value of prognostic testing in patients with known or suspected ischemic heart disease: a basis for optimal utilization of exercise technetium-99m sestamibi myocardial perfusion single-photon emission computed tomography

OBJECTIVES: This study assessed the incremental prognostic implications of normal and equivocal exercise technetium-99m (Tc-99m) sestamibi single-photon emission computed tomography (SPECT) and sought to determine its incremental prognostic value, impact on patient management and cost implications. BACKGROUND: The prognostic implications of Tc-99m sestamibi SPECT are not well defined, and risk stratification using this test has not been explored. METHODS: We studied 1,702 patients referred for exercise Tc-99m sestamibi SPECT who were followed up for a mean (+/- SD) of 20 +/- 5 months. Patients with previous percutaneous transluminal coronary angioplasty or coronary artery bypass surgery were excluded. The SPECT studies were assessed using semiquantitative visual analysis. Cardiac death and myocardial infarction were considered "hard" events, and coronary angioplasty and bypass surgery > 60 days after testing were considered "soft" events. RESULTS: Of the 1,702 patients studied, 1,131 had normal or equivocal scan results. A total of 10 events occurred in this group (1 cardiac death and 1 myocardial infarction [0.2% hard events]; 4 coronary angioplasty and 4 bypass surgery procedures [0.7% soft events]). The rates of hard events and referral to catheterization after SPECT were similarly low in patients with a low (< 0.15), intermediate (0.15 to 0.85) and high (> 0.85) post-exercise treadmill test (ETT) likelihood of coronary artery disease. With respect to scan type, patients with normal, probably normal or equivocal scan results had similarly low hard event rates. In the 571 patients with abnormal scan results, there were 43 hard events (7.5%) and 42 soft events (7.4%) (p < 0.001 vs. 1,131 patients with normal scan results for both). When the complete spectrum of scan responses was considered, SPECT provided incremental prognostic value in all patient subgroups analyzed. However, the nuclear scan was cost-effective only in patients with interpretable exercise ECG responses and an intermediate to high post-ETT likelihood of coronary artery disease and in those with uninterpretable exercise ECG responses and an intermediate to high pre-ETT likelihood of coronary artery disease. CONCLUSIONS: Normal or equivocal exercise Tc-99m sestamibi study results are associated with a benign prognosis, even in patients with a high likelihood of coronary artery disease. Although incremental prognostic value is added by nuclear testing in all patient subgroups, a testing strategy incorporating nuclear testing proved to be cost-effective only in the groups with an intermediate to high likelihood of coronary artery disease before scanning.     

HMPAO SPECT in Parkinson's disease before and after levodopa: correlation with dopaminergic responsiveness

Regional cerebral perfusion was evaluated by SPECT with technetium 99m hexamethylpropyleneamine oxime (99mTc HMPAO) as a tracer in 21 patients presenting with Parkinson's disease and in 11 normal controls. In the parkinsonian patients, scans were performed both off treatment, and after levodopa, and clinical dopaminergic responsiveness was evaluated. Uptake of HMPAO by the basal ganglia was significantly decreased in the parkinsonian subjects, compared with normal controls. This reduction was seen in both responders (n = 14) and non-responders (n = 7) to dopaminergic treatment. Uptake of HMPAO by the basal ganglia rose after treatment with levodopa, but the change was similar in both responders and non-responders. By contrast a striking difference in cortical HMPAO uptake was found between responders and non-responders, with significantly lower uptake in the medial temporal and posterior parietal cortex in the non-responders. This reduction was symmetrical. Basal ganglia perfusion assessed by this technique is unlikely to be of use in the diagnosis of Parkinson's disease that is responsive to dopaminergic treatment. The presence of extensive cortical involvement on a baseline scan correlates with a lack of dopaminergic responsiveness, however, and this may be useful diagnostically.     

Abdominal pain, fresh blood in the anus

A 60-year-old lady with type II diabetes, arterial hypertension and 'melancholia' was treated with Lithium, a neuroleptic (Leponex) and an ACE inhibitor (Reniten). She was referred to our hospital because of abdominal pain, subfebrile temperatures, diarrhea and hematochezia. The radiological and sonographic examinations showed a thickened wall of the left hemicolon. Colonoscopy revealed a sharply delineated segment with pronounced inflammation in the descending colon and the proximal sigmoid colon, suggestive for an ischemic colitis. Histology of the inflamed colon was compatible with this diagnosis. Under suspended enteral feeding and antibiotic therapy the symptoms disappeared within two weeks, and a control colonoscopy six weeks later was completely normal. 1 1/2 years later the patient suffered from a second episode of ischemic colitis exactly a the same site. Again, complete cure was achieved by conservative treatment.     

Embryonic development of an endoparasitoid, Microplitis croceipes (Hymenoptera: Braconidae) in cell line-conditioned media

While relatively rare, the most common benign tumor of the spleen is the hemangioma. We report a case of a noncalcified splenic hemangioma found incidentally on a technetium-99m methylene diphosphonate (Tc-99m MDP) bone scan. Tc-99m MDP may have been accumulated by iron, which was deposited extensively within the hemangioma.     

Technetium-99-labeled leukocytes in diagnosing diabetic osteomyelitis in the foot

Hexamethylpropylamineoxine (HMPAO)-labeled leukocytes were studied to examine the scintigraphic significance of the procedure in diagnosing bone infection in patients with chronic nonhealing foot ulcerations. Fifty-two patients were scanned with Technetium-99-labeled white blood cells and scintigraphic results were compared with histological analysis, bone culture, and radiographic findings. Twenty-one patients demonstrated positive uptake with imaging and focal accumulation of leukocytes at the area of suspected infection. Sensitivity, specificity, and accuracy were calculated and found to be 86%, 90%, and 88%, respectively. Thirty-one members of the population were also scanned with Tc-99 methylene diphosphate (MDP) triphasic scintigraphy. Sensitivity equaled 91% and specificity was found to be significantly lower (40%) when compared with the leukocyte-labeled scans. Technetium-99 (HMPAO) leukocyte scintigraphs demonstrated a significantly higher specificity and accuracy rate when compared with Technetium-99 (MDP) triphasic scans.     

Better visualization of retinoblastoma metastases with Tc-99m sestamibi versus Tl-201

Tc-99m sestamibi has been shown to accumulate in several primary malignant tumors, but data regarding its use in the detection of distant metastases are limited. Despite its physical limitations, Tl-201 now has a definite place in the routine evaluation of certain primary and metastatic tumors. This report describes the value of Tc-99m sestamibi and its superiority to Tl-201 in the visualization of distant metastases in a 2-year-old girl with bilateral retinoblastoma. Three sites of soft tissue and bone metastasis were demonstrated by Tc-99m sestamibi imaging. Of these metastases, the one in the parieto-occipital region showed evident Tl-201 uptake, while the other two in the right arm and chest wall showed only slightly increased uptake, which could hardly be spotted without the confirmation of a later Tc-99m sestamibi scan. The scintigraphic findings were confirmed with histopathologic examination. Tc-99m sestamibi scan is effective and superior to Tl-201 in the detection of distant soft tissue and bone metastases from retinoblastoma.     

Cholescintigraphy in the diagnosis of Rotor syndrome

A 2-year-old boy with Rotor syndrome was studied with Tc-99m N-(di-isopropylphenyl carbamoylmethyl) iminodiacetic acid (DIPA). In this patient, the liver was not visualized, and there was persistent visualization of the cardiac blood pool and along with prominent kidney excretion. It is concluded that Tc-99m DIPA cholescintigraphy may be helpful in the diagnosis of Rotor syndrome.     

Trial of new intraocular lens power calculation following phototherapeutic keratectomy]

Thirty-one men (age range, 46-76 years; mean age, 64.8 years) with intrathoracic masses suggesting possible malignancy on the basis of chest radiography or CT underwent preoperative Tc-99m MIBI SPECT examinations. Diagnosis was confirmed on pathologic examinations of samples obtained either at thoracotomy, esophagectomy, or by biopsy. Twenty-five patients had primary lung cancer, including squamous cell carcinoma, large cell carcinoma, adenocarcinoma, and small cell carcinoma. Two patients had lymphomas with spread to the mediastinum, and three patients had extrathoracic primary cancers (one squamous cell carcinoma of esophagus, one squamous cell carcinoma originating from a head and neck tumor, and one metastatic mediastinal leiomyosarcoma). One patient with a tuberculoma had negative results of the Tc-99m MIBI examination. Tc-99m MIBI had a 86.7% sensitivity rate, a 0% false-positive rate, and a 100% positive predictive value to detect malignant intrathoracic masses. There was a 13% false-negative rate, however, suggesting that MIBI-SPECT may underdiagnose malignant lesions. SPECT findings of these 31 patients can be classified as 1) mass with increased uptake, n = 23; 2) ring-like appearance of increased uptake, n = 3; 3) mass with absent uptake, n = 4; and 4) photon-deficient mass, n = 1. Absent uptake in patients with mass lesions could be explained by necrosis of the lesion (caseation necrosis or massive tumor necrosis with or without bleeding). Most malignant intrathoracic masses are Tc-99m MIBI avid and may be detected with a high degree of sensitivity and with an excellent positive predictive value. A positive MIBI scan may help in the clinical diagnosis of malignancy. The use of Tc-99m MIBI could serve not only as a tumor imaging agent, but also may be used to determine the extent of spread and potentially the chemotherapeutic responsiveness of a tumor.     

Ischemic colitis

Colon ischemia is a well-recognized clinical entity that often occurs spontaneously in patients over the age of 50 years. Many previous cases of nonspecific colitis are now felt to have been secondary to an ischemic event. In contrast to patients with acute mesenteric ischemia and extensive necrosis of the small bowel, the majority of patients with isolated colon ischemia follow a benign clinical course. Most patients present days, weeks, or months after the initial ischemic insult, and many may not have any recognizable antecedent episode of colon ischemia. However, some patients develop a fulminant form of the disease that causes colon infarction and death if not treated early. A high index of suspicion is necessary to make the diagnosis in the hospitalized patient. Endoscopy is recommended to confirm the diagnosis and the extent of injury and to monitor progression or resolution of disease. Aggressive management is of paramount importance to minimize the damage to the ischemic colon and reduce the otherwise high in-hospital mortality rate. Surgical intervention is indicated for patients with evidence of peritonitis or transmural infarction or perforation of the colon and for patients with chronic symptomatic colitis or stricture.     

Differences in factors associated with silent and symptomatic MRI T2 hyperintensity lesions

SPECT using Tc-99m MIBI was performed in patients with brain tumors in order to determine Tc-99m MIBI uptake in brain tumors and to evaluate the efficacy of MIBI imaging in the assessment of treatment response. A MIBI uptake index was calculated on SPECT imaging. All tumors with a MIBI-index higher than 7.5 were malignant. In the tumors evaluated before and after radiochemotherapy, the MIBI-index immediately following therapy correlated with treatment response 2 months after therapy. Thus, semiquantitative assessment using Tc-99m MIBI SPECT imaging may be useful in the evaluation of treatment response.     

Resting and acetazolamide-challenged technetium-99m-ECD SPECT in transient global amnesia

This report describes the case of a 42-yr-old woman with systemic lupus erythematosus who presented with septic shock. Initially, a source of infection could not be found and the patient was started on stress dose corticosteroids and antibiotics. A CAT scan revealed thickened colon and endoscopy revealed possible ischemic colitis. She soon developed peritonitis, and was taken to surgery where gastrointestinal mucormycosis was found. The patient died despite amphotericin therapy.     

A case of obstructive colitis caused by possible colostomy dysfunction

A case of obstructive colitis caused by possible stricture of colostomy is herein reported. A 58 year old female with an obstructive sigmoid colon cancer underwent an emergency descending decompression colostomy. At laparotomy, the colon proximal to the carcinoma was markedly distended and the bowel wall was thin, but the serosa appeared normal. Postoperatively, however, abdominal pain and distension persisted and low grade fever developed. Diarrhea through the colostomy continued. Nine days after the initial surgery, she underwent a left hemicolectomy. An abnormally thickened segment was identified in the resected specimen; normal mucosa was lost and several pseudopolyps were scattered. Histopathological findings of the abnormal segment were consistent with obstructive colitis. A preserved segment of normal mucosa intervened between the site of colostomy and the abnormal segment of obstructive colitis. A possible stenosis of the colostomy was considered to have caused colostomy dysfunction and subsequent obstructive colitis. She was complicated with anastomotic leakage due to the diseased colon being used for anastomosis. Obstructive colitis should be kept in mind in patients with obstructive colonic carcinomas who complain of persistent abdominal pain, distension and diarrhea in the early postoperative period after colostomy.     

Arteriovenous fistula after renal biopsy in children

Tc-99m MIBI is used as a tumor imaging agent and has been proposed to measure p-glycoprotein function, which plays an important role in tumor multidrug resistance to chemotherapy. It has been reported that lung cancer and breast cancer with a high retention of Tc-99m MIBI have been more responsive to chemotherapy than tumors with low retention. Thus Tc-99m MIBI SPECT could be used as a measure of p glycoprotein function and consequently may serve as a predictor of the tumor's responsiveness to chemotherapeutic agents. Described here are two patients with lymphomas, one with non-Hodgkin's lymphoma and the other with Hodgkin's disease, who underwent Tc-99m MIBI thoracic SPECT before and after chemotherapy. The sequential studies demonstrated a reduction in tumor size and diminished tumor uptake in one patient and disappearance of tumor uptake after a course of chemotherapy in the other patient. The data suggest that elevated Tc-99m MIBI uptake in a tumor as a result of retention by p glycoprotein not only demonstrates mediastinal involvement of lymphomas but also may be used to forecast responsiveness to chemotherapy.