How useful is ultrasonography in suspected acute osteomyelitis?

Sonographically detected subperiosteal fluid and periosteal irregularity have recently been proposed as diagnostic features of osteomyelitis. The purpose of this study was to determine the diagnostic accuracy of ultrasonography for suspected osteomyelitis. Nineteen patients were investigated prospectively with high-resolution ultrasonography for the presence of subperiosteal fluid or cortical irregularity. Diagnosis was established by surgery (three cases) or by results of other tests and clinical follow-up. Sixteen patients were diagnosed as having osteomyelitis, with positive ultrasonography in ten (sensitivity = 63%). Two ultrasonographic studies were false-positive; diagnostic accuracy was 58%. Thus, ultrasonographic results may be potentially misleading, emphasizing the importance of clinical judgment and results of other tests.

The role of high dose 67-gallium scintigraphy in staging untreated patients with lymphoma.

BACKGROUND: Gallium-67 (67Ga) scintigraphy has been reported to be of limited value in staging lymphoma patients. However, recent technical advances in radionuclide imaging have potentially enhanced the usefulness of this method. AIMS: The purposes of this study were to determine the current: (1) sensitivity and specificity and (2) impact on clinicians' treatment decisions of 67Ga scans performed at a teaching hospital. METHODS: There were 46 newly presenting patients with lymphoma (13 with Hodgkin's disease (HD) and 33 with non-Hodgkin's lymphoma [NHL]). Planar 67Ga scans were performed up to eight days following injection of 300 MBq (8 mCi) with images interpreted by consensus of two blinded observers; sensitivity and specificity were determined on a lesion by lesion basis in comparison to computed tomography (CT) scans, palpation of peripheral lymph nodes and abdominal lymphangiograms (n = 5). The contribution of 67Ga scans to clinicians' treatment decisions was also independently assessed by an experienced oncologist. RESULTS: Gallium-67 scan sensitivity and specificity were 80% and 96% for HD and 59% and 98% for NHL. Initial treatment plans were modified in three individuals (7%; 95% confidence intervals = 3-10%) due to lesions on the 67Ga scan not prospectively detected or considered equivocal on other tests. CONCLUSIONS: Only a small proportion of newly diagnosed lymphoma patients benefit from staging with state of the art planar high dose 67Ga imaging.

The significance of isolated gallium-67 uptake in the hilar lymph nodes of an untreated lymphoma patient.

A 69-year-old woman presented with non-Hodgkin's lymphoma of the right ilioinguinal region in whom bilateral uptake of Ga-67 in hilar lymph nodes was noted on thoracic SPECT. There were no Ga-67 abnormalities elsewhere within the thorax, and a chest CT scan was also normal. The patient received radiotherapy to the inguinal region and remained in clinical remission for 28 months following treatment. She subsequently relapsed at a number of peripheral lymph node sites, but not in the chest. The authors postulate that isolated hilar uptake of Ga-67 SPECT may not be clinically significant in some untreated patients with lymphoma. This scintigraphic finding should be interpreted cautiously, particularly when other chest imaging studies remain negative.

A case of metastatic malignancy masquerading as a hepatic hemangioma on labeled red blood cell scintigraphy.

A 36-yr-old woman with a past history of gastric neuro-endocrine carcinoma (carcinoid tumor) underwent 99mTc-red blood cell (RBC) scintigraphy for evaluation of a 2-cm echogenic liver mass demonstrated on ultrasound. Scan findings were typical of a cavernous hemangioma. On follow-up, however, there was progressive lesion enlargement; histopathology of the resected mass revealed neuro-endocrine carcinoma. This case report, one of the few examples of a false-positive 99mTc-RBC scan, highlights the need for cautious evaluation of focal liver masses, even when there are typical scintigraphic features of cavernous hemangioma.

Volume expanded diuretic renography in the postnatal assessment of suspected uretero-pelvic junction obstruction.

Controversy surrounds the role of 99mTc-diethylenetriamine pentaacetic acid renography in suspected uretero-pelvic junction obstruction in early life. Accordingly, we retrospectively reviewed 18 patients (28 hydronephrotic kidneys) with a mean age of 2 mo (range: 1 wk-6 mo) who underwent a total of 36 scans using intravenous volume expansion (10 ml/kg) and furosemide diuresis (1 mg/kg). Initial scans were classified as obstructed, not obstructed or indeterminate using differential renal function, furosemide washout T 1/2 and visual assessment of tracer clearance. Those initially classified as obstructed (n = 8) have been surgically confirmed. In the indeterminate (n = 6) and nonobstructed (n = 14) groups, three and two kidneys, respectively, developed obstruction on progress scans. Mean follow-up in the nonsurgical patients was approximately 9 mo (range: 4-17 mo). A total of 13 kidneys had developed obstruction by renographic criteria, and to date 12 have surgical confirmation. Our data indicate that: (1) scans classified as obstructed correlate well with surgery; (2) an initial classification of indeterminate or nonobstructed does not exclude later development of obstruction; and (3) serial scans correctly stratify children with possible uretero-pelvic junction obstruction.

Hypertension associated with diffuse small artery calcification: a case report.

Renal ultrasound examination, performed following a urinary tract infection in a 4.5-year-old girl with triple X syndrome, showed multiple echogenic foci at the corticomedullary junction in both kidneys. She was asymptomatic but had hypertension with echocardiographic evidence of left ventricular hypertrophy. Computerised tomographic scan revealed foci of calcification in the kidneys, spleen and pancreas. On biopsy calcification was found in the internal and external elastic laminae of the superficial temporal artery and in the internal elastic lamina of a renal arcuate artery. Intimal fibrosis was mild and focal. No other arterial calcification was demonstrated radiographically or by ultrasound. Biochemical and hormonal profiles revealed no abnormality except hypercalciuria. The aetiology and prognosis of this child's condition are unknown. Although similar ultrasound and histological appearances have been described in pseudoxanthoma elasticum and in idiopathic arterial calcification of infancy, there is no evidence that the child has either of these conditions.

Vascular compression of the superior infundibulum causing calyceal obstruction. Scintigraphic findings.

Radionuclide imaging in obstructive uropathy has concentrated on disorders of the pelviureteric junction and lower urinary tract. There is a paucity of information, however, available on the scintigraphic manifestations of disorders of the calyces and infundibulum. These conditions may be responsible for similar symptoms, and thus recognition of abnormal retention of activity within one or more calyces offers important diagnostic information. One of these disorders is vascular obstruction of the superior infundibulum, and this report describes the radionuclide appearance of this surgically curable condition.

Investigation of focal hepatic lesions: is tomographic red blood cell imaging useful?

Noninvasive diagnosis of cavernous hemangioma of the liver is an important step in the investigation of patients with focal hepatic lesions since biopsy may result in life-threatening hemorrhage. To determine the diagnostic accuracy of 99m-technetium red blood cell (99mTc-RBC) imaging with tomography, 50 patients with various types of focal liver lesions were studied. Thirty-two patients had 45 hemangiomas and 7 other benign lesions while 18 patients had either primary (n = 8) or secondary (n = 10) hepatic malignancies. Tomographic imaging identified 12 more hemangiomas than planar imaging, improving sensitivity from 53% to 80%, and was found most useful for detection of smaller lesions (mean size, 2.1 cm). Specificity for hemangiomas was 100% with all lesions greater than 1.9 cm showing the characteristic scintigraphic pattern of blood-pooling on delayed images. There was excellent agreement between 2 independent observers concerning interpretation of tomographic images (89% for the hemangioma group and 100% for other patients). Therefore 99mTc-RBC scintigraphy with tomography is an accurate diagnostic technique in the investigation of cavernous hemangiomas. Its major value resides in its ability to distinguish hemangiomas from other types of hepatic pathology.

Diagnosis and treatment of antenatal uropathies.

Thirty-five patients with significant fetal hydronephrosis detected on antenatal ultrasound had postnatal investigations which included ultrasound, 99mtechnetium diethylenetriamine pentacetic acid (99mTcDTPA) renal scans and micturating cystourethrograms. Antenatal and postnatal ultrasound were unable to determine reliably the level of obstruction causing the hydronephrosis. The 99mTcDTPA renal scan was useful in determining the necessity and timing of surgery, but could not exclude vesico-ureteric reflux. Seven patients required surgery in the neonatal period and a further seven children had surgery because of deterioration of the scan appearance on follow-up studies performed at 3, 6 and 12 months of age and then at longer time intervals. Twenty patients (almost 60%) have been managed conservatively for a mean of 28 months (range: 12 months-7 years) with no deterioration in renal function.

Tc-99m DTPA uptake in Paget's disease of the left ilium.

Skeletal visualization during dynamic renal imaging is an uncommon finding that has previously been related to underlying neoplastic disease. The authors report a case of active Paget's disease of the left ilium resulting in uptake of Tc-99m DTPA in the arterial flow and early blood pool images. This report emphasizes that it is the increased blood flow, rather than the bone pathology per se, that determines uptake of Tc-99m DTPA in Paget's disease.

Can quantitative renography predict the outcome of treatment of atherosclerotic renal artery stenosis?

The accuracy of quantitative gamma camera renography in predicting outcome of treatment was assessed in 31 patients with atherosclerotic renal artery stenosis. Glomerular filtration rate, renal perfusion, relative renal function, and mean parenchymal transit time were calculated before and after treatment (renal artery angioplasty or vascular surgery). Patients were also assessed during the follow-up period of up to 6 years. On the pre-treatment study, nine patients did not have prolongation of parenchymal transit time in the kidney on the side of the renal artery stenosis. Despite technically successful angioplasties, none of these patients showed a significant reduction in blood pressure or improvement in renal function. Twenty-two patients had prolongation of parenchymal transit time in the affected kidney. Three suffered complications of treatment, and the remaining 19 showed improvement in blood pressure control, reduction in parenchymal transit time, and improvement in relative renal function. Quantitative renography accurately predicted those patients who improved following intervention for atherosclerotic renal artery stenosis. On progress evaluation, patients with recurrent stenoses were easily identified.

Atypical appearance of an hepatic hemangioma with technetium-99m red blood cell scintigraphy.

Three-phase 99mTc red blood cell scintigraphy is an established technique for distinguishing hemangiomas from other focal liver lesions. The most widely recognized feature is the perfusion to blood-pool "mismatch" characterized by decreased or normal arterial perfusion, with lesion activity which progressively increases over 1-2 hr. Although increased arterial vascularity of hemangiomas has been described, such cases either involved small portions of the lesion only or occurred in lesions not conclusively proven to be hemangiomas. We report a case of an angiography proven hemangioma with increased arterial vascularity involving a significant portion of the lesion as well as intense early blood-pool activity similar to that seen on delayed imaging. This case emphasizes the diverse appearance of hepatic hemangiomas using 99mTc blood cell scintigraphy.

Preoperative assessment as a predictor of mortality and morbidity after lung resection.

To refine the functional guidelines for operability for lung resection, we prospectively studied 55 consecutive patients with suspected lung malignancy thought to be surgically resectable. Lung function and exercise capacity were measured preoperatively and at 3 and 12 months postoperatively. Preoperative pulmonary scintigraphy was used to calculate the contribution to overall function by the affected lung or lobe and to predict postoperative lung function. Pneumonectomy was performed in 18 patients, lobectomy in 29, and thoracotomy without resection in six. No surgery was attempted in two patients who were considered functionally inoperable. Cardiopulmonary complications developed in 16 patients within 30 days of surgery, including three deaths. The predictions of postoperative function correlated well with the measured values at 3 months. For FEV1, r = 0.51 in pneumonectomy (p less than 0.05) and 0.89 in lobectomy (p less than 0.001). Predicted postoperative FEV1 (FEV1-ppo), diffusing capacity (DLCO), predicted postoperative DLCO (DLCO-ppo) and exercise-induced arterial O2 desaturation (delta SaO2) were predictive of postoperative complications including death and respiratory failure. In patients who underwent pneumonectomy, the best predictor of death was FEV1-ppo. The predictions were enhanced by expressing the value as a percentage of the predicted normal value (% pred) rather than in absolute units. For the entire surgical group a FEV1-ppo greater than or equal to 40% pred was associated with no postoperative mortality (n = 47), whereas a value less than 40% pred was associated with a 50% mortality (n = 6), suggesting that resection is feasible when FEV1-ppo is greater than or equal to 40% pred.(ABSTRACT TRUNCATED AT 250 WORDS)

Risk of aortic aneurysm surgery as assessed by preoperative gated heart pool scan.

Gated heart pool scan measuring left ventricular ejection fraction (LVEF) was performed preoperatively in 72 patients presenting for elective repair of abdominal aortic aneurysm. Patients with a positive cardiac history were more likely to have a LVEF of less than or equal to 45 per cent (P less than 0.001). The operative mortality rate was 4 per cent. Each of three patients who died had a LVEF less than or equal to 35 per cent and developed cardiac failure which led to renal failure. Five other patients developed cardiac failure manifested by acute pulmonary oedema during the early postoperative period. There was no statistically significant association between a positive cardiac history and the occurrence of postoperative cardiac failure or death. However, patients with a LVEF of less than or equal to 45 per cent were more likely to develop postoperative cardiac failure (P = 0.004) while patients with a LVEF of less than or equal to 35 per cent had a greater chance of dying (P less than 0.001). No patient died with a LVEF greater than 35 per cent. Preoperative evaluation of LVEF can select patients at high risk of cardiac death from repair of abdominal aortic aneurysm. Such patients could be followed conservatively if they remain asymptomatic and the aneurysm does not enlarge. If operation is considered mandatory, patients with a low LVEF should receive intensive perioperative monitoring with enhancement of ventricular performance.

Dipyridamole-thallium scan for screening of coronary artery disease prior to vascular surgery.

Patients with extracranial cerebrovascular disease and peripheral vascular disease are at increased risk of ischaemic heart disease with resulting increased risk of early and late mortality following vascular reconstruction. Over a two year period, 67 patients undergoing carotid or aortic surgery were investigated preoperatively with dipyridamole-thallium scan. There were three positive scans in the first 17 patients; two of these patients suffered a postoperative myocardial infarction (one fatal), compared to none of 14 who had a negative scan (p = 0.02). There were seven positive scans in the next 50 patients. Patients with left main trunk or triple vessel disease were recommended to have coronary artery bypass prior to or combined with the vascular reconstruction. There were no deaths or postoperative myocardial infarction in this group, this improvement in morbidity being statistically significant (p = 0.01). Dipyridamole-thallium scanning is an effective screening procedure for coronary artery disease. Patients with a positive scan are at increased risk of postoperative myocardial infarction following vascular reconstruction. Further investigation with coronary arteriography prior to vascular reconstruction is recommended in patients with positive scans. Coronary artery bypass should be performed prior to or combined with the vascular reconstruction in patients with left main trunk or triple vessel disease.

Cutaneous gallium uptake in patients with AIDS with mycobacterium avium-intracellulare septicemia.

Gallium imaging is increasingly being used for the early detection of complications in patients with AIDS. A 26-year-old homosexual man who was HIV antibody positive underwent gallium imaging for investigation of possible Pneumocystis carinii pneumonia. Widespread cutaneous focal uptake was seen, which was subsequently shown to be due to mycobacterium avium-intracellulare (MAI) septicemia. This case demonstrates the importance of whole body imaging rather than imaging target areas only, the utility of gallium imaging in aiding the early detection of clinically unsuspected disease, and shows a new pattern of gallium uptake in disseminated MAI infection.

Metastatic uterine cervical cell carcinoma to myocardium.

Metastatic involvement of the myocardium is a rare premorbid diagnosis. Multiple examinations were performed on a 43-year-old woman who presented with ischemic chest pain, palpitations, and nausea. Twelve months previously, a poorly differentiated squamous cell carcinoma of the uterine cervix was removed with no evidence of metastases or residual tumor. Following numerous investigations, a provisional diagnosis of cardiac tumor was made. At operation, involvement of the septum, inferior wall, and apex with some extension into the distal anterior wall was noted. Histology confirmed nonkeratinizing cell carcinoma in keeping with metastases from the uterine cervix.

The I-131 rose bengal excretion test is not dead.

One hundred and thirty I-131 Rose Bengal Excretion Studies (RBI) were performed on 84 patients over nine years. In 90% (56/60) of cases with biliary atresia, the 72-hour RBI was less than or equal to 7%. In only 12.5% (3/24) of cases with neonatal hepatitis was the 72-hour RBI less than or equal to 7%. The accuracy of the test was 91% with a specificity of 88%. Thirty patients later were studied following a Kasai procedure. The RBI test reliably predicted the patency of the anastomosis. The authors conclude that the 72-hour RBI is a reliable test in the diagnosis of biliary atresia and in the documentation of biliary patency following surgery, provided adequate care is taken in stool collection and measurement.

Special considerations in the pediatric use of radionuclides for kidney studies.

Radionuclide renal studies are particularly well suited to pediatrics as renal problems in children usually are part of a dynamic process which requires serial assessment. The absence of side-effects and the low radiation dose has added to their popularity in pediatrics. A number of different renal parameters can be evaluated using the appropriate radiopharmaceutical and method of analysis. The renal study is of value to assess patients with hydronephrosis both pre-operatively and for serial follow-up post-operatively, as well as to distinguish obstructive from non-obstructive uropathy. Perfusion to the kidney may be assessed and ischemic areas detected in children with hypertension or trauma. The renal scan commonly is used in patients with congenital anomalies such as ectopic and duplex kidneys, nonvisualized kidney on IVP and in children with oliguria or anuria secondary to diseases such as acute tubular necrosis, hemolytic uremic syndrome, and renal vein thrombosis. It frequently is done as an emergency procedure in neonates. In conjunction with the IVP and ultrasound, the renal study is useful in some cases of abdominal mass to distinguish between hydronephrosis, cystic kidneys and tumors.