Scintigraphic Appearance Research Articles

Magnetic resonance imaging in osteoarthritis of the knee: correlation with radiographic and scintigraphic findings.

Twelve knees with a range of severity of knee osteoarthritis were assessed by magnetic resonance imaging (MRI) and technetium-99m labelled hydroxymethylene diphosphonate scintigraphy. Five magnetic resonance pulse sequences were evaluated. Proton density (TR = 1000, TE = 26 ms) and STIR (TR = 1500, TI = 100, TE = 30 ms) were chosen for further use. Abnormalities shown by MRI included joint effusions, meniscal disruption, hyaline cartilage thinning, subchondral signal changes, pseudocysts, and heterogeneity of signal from osteophytes. Certain MRI and scintigraphic appearances correlated: (a) 'hyperintense osteophytosis' and ipsilateral 'tramline' scintigraphic uptake, suggesting increased fat content in 'active' osteophytes; (b) subchondral signal change and 'extended' pattern, possibly reflecting inflammation, synovial leak, or fibrovascular repair; (c) patellofemoral joint signal changes and patellar isotope uptake.

Detection of focal nodular hyperplasia with liver colloid single photon emission computed tomography: a case report and review of the literature

Focal nodular hyperplasia (FNH) is a benign hamartomatous liver mass (Robbins et al, 1984). It is usually identified incidentally during ultrasonographic examination, other diagnostic procedures or autopsy. The patients are often asymptomatic (Drum, 1982). Physical examination is found to be normal in most of the cases. Jaundice, hepatomegaly, palpable mass, and chronic intermittent vague abdominal pain, especially in the right upper quadrant, may be present in some patients. Eighty-eight per cent of the cases are female, of whom 80% give a history of oral contraceptive or supplemental oestrogen use (Kerlin et al, 1983). The lesion may be solitary (55%) or multiple, and it is usually located in the right lobe of the liver (Rogers et al, 1981), varying in size between 1 and 20 cm, and containing hepatocytes, bile ducts and Kuppfer cells (Rogers et al, 1981; Robbins et al, 1984). Colloid scintigraphic appearance may be hyperactive (40%), hypoactive (30–60%) or normoactive (30–55%) (Diament et al, 1982; Kerlin et al, 1983; Rogers et al, 1981; Welch et al, 1985). A central, stellate-shaped collageneous scar with peripherally radiating septa is the typical histopathologic feature of FNH (Kerlin et al, 1983; Rogers et al, 1981). We present a case of FNH with planar colloid scintigraphy demonstrating slightly increased uptake in the ultrasonographically detected lesion. Single photon emission computed tomography (SPECT) showed a hyperactive region at the lesion site.

Hashimoto??s Thyroiditis Presenting as Hot and Cold Nodules

A case of Hashimoto's thyroiditis is presented. I-123 thyroid scintigraphy demonstrated a hot nodule in the left lobe and a cold nodule in the right, which was well visualized by Tl-201 imaging. This unusual scintigraphic appearance is demonstrated, and its possible explanation discussed.

SCINTIGRAPHIC PATTERN OF 99mTc–MDP UPTAKE IN EXERCISE INDUCED PROXIMAL PHALANGEAL TRAUMA IN HORSES

Sixty–nine horses having radionuclide bone scans of the foredigit region between 1985 and 1988 were retrospectively analyzed for proximal phalangeal cortical 99mTc–MDP uptake. Patterns of uptake were determined and the factors of age, breed, sex, occupation, and duration of signs prior to imaging were assessed. Twenty–three horses had abnormal proximal phalangeal uptake. Two patterns of uptake were seen, either as linear, diffuse or focal, discrete, fusiform–shaped cortical uptake. The dorsal cortex was always affected in these 23 horses; the palmar cortex was affected in 14 horses, and this uptake was always linear in appearance. There was significant correlation of proximal phalangeal cortical uptake and regular jumping activity, either as a jumping, hunting or three–day event horse (p < .005). No correlations were determined between uptake and the factors of age, breed, sex or duration of signs prior to imaging. The scintigraphic appearance patterns were similar to those seen in scintigraphic studies of exercise induced traumatic bone injuries in humans.

Scintigraphy in the assessment of anterior knee pain

Sixty knees presenting with chronic anterior pain were investigated. A diffusely increased uptake indicated sympathetically mediated pain provided other diagnoses such as synovitis or widespread arthrosis were excluded. Focal uptake was not specific to any one condition, but could occur in chondromalacia patellae or recent dislocations. However, the commonest appearance found in chondromalacia patellae was a normal scan. A characteristic scintigraphic appearance in symptomatic postpatellectomy knees, which has not been previously reported, was increased uptake in the femoral groove. In all the cases where no clinical or arthroscopic diagnosis was made, the bone scan was normal. The use of radioisotope scintigraphy is recommended in the problem knee presenting with anterior pain.

Misleading appearances of the bladder on pediatric genitourinary imaging.

The authors reviewed images of the bladder on 100 consecutive Tc-99m DTPA pediatric renograms for any abnormal distribution of radionuclide or asymmetry suggestive of anatomic bladder abnormality. The results were correlated with radiographic contrast voiding cystourethrograms and ultrasound examination. Of 81 patients with adequate bladder imaging, 50 (62%) had symmetric and uniform distribution of radioactivity within the bladder. Thirty-one patients (38%) had a sufficiently abnormal bladder appearance to suggest anatomic abnormality. Of these 31 patients, 27 had contrast cystograms and ultrasound evaluation; only one (4%) had a proven bladder abnormality which correlated with the abnormal scintigraphic appearance. The appearance of the bladder on pediatric genitourinary imaging is a nonspecific and unreliable indicator of anatomic bladder abnormality.

The pyramidal lobe

The thyroid scintigraphs of 207 patients were examined with a view to investigate the anatomical origin of the pyramidal lobe (PL) and in order to determine the incidence of its scintigraphic detection. The PL was visualized in 41% of the cases studied with a greater incidence among the females as compared to the males. It was established that the likelihood of the PL arising from the isthmus of the thyroid or its lobes was about the same. Further, it was observed that the isthmal PL was usually located in the mid-line rather than laterally, in which case it was more often deviated to the left than to the right. The scintigraphic visualization of the PL was seen to increase with the size of the gland but in large goitres it was difficult to detect. It evolves that although at times, there might be a discrepancy between the apparent and the actual location of the PL due to the presence of overlying tissue, in a majority of cases, the scintigraphic appearances do in fact reflect the true picture.

Delayed lung scintigraphy with N-isopropyl-I-123-p-iodoamphetamine in lung cancer and inflammatory disease : Suematsu T, Narabayashi I, Takada Y et al. Department of Radiology, Hyogo Medical Center for Adults, Nishinomiya. Jpn J Nucl Med 1989;26:45–53

Lung studies with N-Isopropyl-I-123-p-Iodoamphetamine (IMP) were performed on patients with lung cancer or inflammatory disease. In the present study, we evaluated the usefulness of the delayed scintigraphy. The subjects consisted of 27 patients with lung cancer (34 lesions), 3 with radiation pneumonitis, 2 with interstitial pneumonitis, 2 with old tuberculous lesion (tuberculomas), 1 with diffuse panbronchiolitis, 1 with pneumonia and 1 with lung abscess. The delayed scintigraphy was performed 24 hr after intravenous injection of 3 mCi IMP, in sitting position. In 10 patients, SPECT images were obtained following the delayed scintigraphy. Delayed scintigraphic appearances of lung cancer were classified into 5 types, high IMP uptake in the area congruent with the lesion of atelectasis and/or obstructive pneumonia (Type I), high IMP uptake in the area surrounded the tumor (Type II), a defect in the area consistent with the tumor and no high IMP uptake in the area surrounded the tumor (Type III), high IMP uptake in the area almost congruent with the tumor (Type IV) and no significant change (Type V). Excluding 10 lesions with Type IV or V, no IMP uptake was seen in the areas congruent with the tumors. Type II was the most frequently observed pattern. Normal scintigrams (Type V) were observed in 8 lesions, whose sizes were fairly small. There was no definite trend caused by difference in histological types of cancers. In 8 patients with viable inflammatory disease of the lung, the delayed scintigrams showed high IMP uptake in the areas congruent with the abnormalities on chest roentgenograms.(ABSTRACT TRUNCATED AT 250 WORDS)

Concept and limits of the reflex sympathetic dystrophy.

Reflex sympathetic dystrophy (RSD) is a clinical syndrome defined in the English literature by pain, dystrophic tissue changes and local disturbance of autonomic function in a limb or part of a limb. Algodystrophy is the common name used for the condition in the French literature, in which the concept also includes the "transient regional osteoporosis" and the "regional migratory osteolysis". We want to discuss three points: 1) Are the RSD, transient regional osteoporosis and migratory osteolysis different diseases or different manifestations of a single condition? We believe that an objective differentiation is not possible between them. Our report about 28 cases of polytopic RSD shows the frequent association in the same patient of these manifestations and we believe that this represents the broad spectrum of a single disease. 2) Is the accepted classic pathophysiologic mechanism of RSD accurate? The conception of a disturbance of autonomic function is not easily linked with its association with conditions such as diabetes, hyperthyroidism, hyperlipidaemia and others. Even more difficult to explain is the association with malignancy and osteomalacia. The deposit of immunoglobulins that we have demonstrated in two cases in the palmar fascia of RSD associated with malignancy suggests a possible immunological mechanism. 3) What are the limits of RSD? The association between RSD and aseptic necrosis of the hip has been reported. Are they two different conditions or is the aseptic necrosis only a more developed form of RSD? Finally, we report the first single case of Munchausen syndrome mimicking a RSD of the hand with the same clinical, radiological and scintigraphic appearance.

The role of scintigraphy in urinary tract infection

There is controversy regarding the role of radiological imaging for urinary tract infection (UTI). The "gold standard" has been the intravenous pyelogram (IVP). Yet, the IVP has a very limited value with only about 25% of children with pyelonephritis demonstrating abnormalities. Ultrasound (US) has recently been advocated as a replacement for the poorly sensitive and poorly specific IVP. However, comparative studies between US and IVP indicate only an equivalent sensitivity and specificity. Cortical scintigraphy with Technetium-99m glucoheptonate (99mTc GH) or 99mTc dimercaptosuccinic acid (99mTc DMSA) has also been advocated as a means of differentiating parenchymal (pyelonephritis) from nonparenchymal (lower UTI) involvement in UTI. The clinical presentation may be misleading especially in the infant and child in whom an elevated temperature, flank pain, shaking chills, or an elevated sedimentation rate are often lacking. The clinician attempts to localize the site of infection for it has a direct bearing upon the therapy. A collecting system infection can often be eradicated with a single oral dose of an appropriate antibiotic, whereas renal parenchymal involvement requires IV therapy for an extended interval. Cortical scintigraphy can localize the site of infection with a high degree of accuracy. Recent studies report a sensitivity of 86% and specificity of 81% of pyelonephritis. This is in contrast to the IVP with a sensitivity of only 24% and US with a sensitivity of only 42%. The scintigraphic appearance of parenchymal infection of the kidney is a spectrum of minimal to gross defects reflecting the degree of histologic involvement that spans from a mild infection to frank abscess. Cortical scintigraphy can be used to monitor the evolution of scarring following infection. Cortical scintigraphy with 99mTc DMSA or 99mTc GH is the method of choice for the initial evaluation of UTI. Not only does it have a very high sensitivity and specificity for differentiating parenchymal from collecting system disease, but it also provides an accurate quantitative measurement of function and in combination with radioiodinated orthoiodohippurate renography and Lasix (furosemide; Abbott Laboratories, North Chicago) diuresis will also differentiate significant obstruction from stasis. The use of radionuclide techniques opens new vistas for the investigation of UTI. Cortical scintigraphy should become the gold standard by which other technologies, therapy, and theoretical considerations of pyelonephritis are measured.

Radiography and Scintigraphy in the Assessment of Early Gonarthrosis

The radiographic and scintigraphic appearances in early gonarthrosis were compared in 62 knees. Early femorotibial osteoarthrosis was found to be confined to one compartment (medial or lateral) of the joint. However, concomitant patellofemoral osteoarthrosis was common. 99Tcm-MDP scintigraphy was consistently positive when the joint space (femorotibial and patello-femoral) was reduced by 75 per cent or more. Joint space narrowing by as much as 50 per cent could be observed in a scintigraphically normal knee. The inconsistency between the radiologic and scintigraphic findings in the earliest stages of gonarthrosis points to the importance of appropriate radiographic technique.

Basic principles of nuclear medicine techniques for detection and evaluation of trauma and sports medicine injuries

Nuclear medicine skeletal imaging is a very sensitive technique for evaluating bone and muscle abnormalities because it can detect minor changes in metabolism and blood flow. The specificity of bone imaging, however, depends on the ability of the nuclear medicine physician to make a differential diagnosis. To aid in making a specific diagnosis, this article describes the various patterns of abnormality in stress fractures, tibial stress syndrome (shin splints), compartment syndrome, enthesopathy, and traumatic fractures. The characteristic scintigraphic appearance of joint injuries, muscle injuries (rhabdomyolysis), and radionuclide arthrography is discussed and the way the scan patterns change with time in these various disorders is described. A brief summary of the basic anatomy and physiology of bone and muscle in normal and injured tissue is presented and the basic mechanisms which cause the various abnormal scan patterns is postulated. In addition, a staging system for stress fractures is presented to help direct the referring physician toward the proper management of the injured patient. In most cases, nuclear medicine skeletal imaging can be used to differentiate between acute muscle injury, tibial stress syndrome, skeletal injury (periosteal reaction, stress fracture, and traumatic fracture) or an abnormality that is entirely associated with the joint or connective tissue. This differential diagnosis is easier if the nuclear medicine procedure is performed within a few days after the onset of injury.

Radiography and scintigraphy in the assessment of early gonarthrosis

The radiographic and scintigraphic appearances in early gonarthrosis were compared in 62 knees. Early femorotibial osteoarthrosis was found to be confined to one compartment (medial or lateral) of the joint. However, concomitant patellofemoral osteoarthrosis was common. 99Tcm-MDP scintigraphy was consistently positive when the joint space (femorotibial and patello-femoral) was reduced by 75 per cent or more. Joint space narrowing by as much as 50 per cent could be observed in a scintigraphically normal knee. The inconsistency between the radiologic and scintigraphic findings in the earliest stages of gonarthrosis points to the importance of appropriate radiographic technique.

Kock continent ileal urinary reservoir. Anatomy and potential pitfalls of radionuclide imaging.

The Kock continent ileal urinary reservoir (Kock pouch) is a new form of urinary diversion that, due to its advantages over previous techniques of urinary bypass, will probably become widespread in urologic practice. When bone imaging is performed in the presence of the Kock pouch, the unusual configuration of the pouch may obscure or simulate osseous lesions. An understanding of the surgical anatomy as well as the planar and SPECT scintigraphic appearances of the Kock pouch is necessary to avoid errors during interpretation. This series of 51 bone images reports on the variable scintigraphic appearance of the Kock pouch. In addition, the incidence and type of potentially avoidable pitfalls in the interpretation of bone imaging when this form of urinary diversion is used are evaluated.

Experimental evaluation of technetium-99m red blood cell radionuclide ventriculography for detecting pericardial bleeding

Abnormal loculated or diffuse blood pools adjacent to the heart have been observed in patients with pericardial bleeding who have been imaged by gated equilibrium radionuclide ventriculography (RNV). To study the scintigraphic appearance of fresh pericardial blood, we performed equilibrium RNV in six dogs with measured volumes (10, 30, or 50 ml) of intrapericardial blood. Loculated and diffuse pericardial blood was simulated by injecting the blood either into an intrapericardial balloon, or freely into the pericardial space. Ability to detect pericardial blood was determined by blinded review, and blood volume analysis was attempted by measuring its scintigraphic thickness, brightness (relative to the left ventricle), extent, and background-subtracted count rate and a peak count index. Detection rates for 10, 30, and 50 ml were all 100% for loculated pericardial blood, and 67%, 100% and 100% for free pericardial blood, with the use of three scintigraphic views. Visually determined “extent” of the abnormal blood pool was the most reliable indicator of pericardial blood volume. When the volume was 30 ml or more, at least 40% of the heart was surrounded in 26 of 27 cases (96%); the specificity of this finding was 90%. We conclude from this animal study that RNV should be a sensitive method for detecting pericardial bleeding; visual appearance permits qualitative assessment of the volume of accumulated labeled blood.

The predictive value of bone scintigraphy after internal fixation of femoral neck fractures

Persisting pain of the hip following internal fixation of fracture of the neck of the femur is often caused by capital necrosis or non-union. In a randomized trial 35 patients had 99Tc m-MDP bone scintigraphy performed 6 weeks, 3, 6 and 12 months after internal fixation of their subcapital fractures with a sliding screw-plate or a sliding nail-plate. The purpose was to find out whether bone scintigraphy could predict capital necrosis or non-union before it shows up on plain radiographs, which happens later. The patients were followed up for an average of 44 months (range 12–64). Radiologically, capital necrosis occurred in five patients and non-union in six. Bone scintigraphy showed decreasing activity in the 1st year after operation in uncomplicated cases ( P < 0.03). However, it was impossible to distinguish patients with capital necrosis or non-union from those with uneventful healing. There were no significant differences in the scintigraphic appearance between groups at most risk, e.g. Garden stage 3 and 4 fractures versus Garden stage 1 and 2, and fixation by sliding nail versus fixation by sliding screw-plate. In conclusion, bone scintigrams during the first 6 months after operation do not reliably predict failure of internal fixation of fractures of the neck of the femur.

Tissue vitality in septic gonitis. 99mTc-DPD scintimetry in puppies.

After a single intraarticular injection of 10(9) Staphylococcus aureus in 12 puppies, septic arthritis developed in all the experimental knees after 48 hours. A considerable variability in scintigraphic appearance was observed. The juxtaarticular growth plates showed either unchanged or slightly decreased uptake except in 1 dog exhibiting a definite increase in tracer uptake. The epiphyseal uptake showed no consistent pattern. The intraarticular pressure of the arthritic joints increased significantly, but was not related to the tracer uptake pattern. We conclude that delayed joint scintigraphy as a single investigation in early septic arthritis does not provide diagnostic information and may be misleading.

Technetium pertechnetate imaging in apparent solitary thyroid nodule.

ABSTRACT 99mTc‐pertechnetate rectilinear scans of the thyroid were performed in 272 patients judged to have solitary thyroid nodules on palpation. Eighty percent of these patients were shown to have decreased uptake in a single thyroid nodule. Further analyses were made among 82 patients who had surgery for such nodules. Again, 90 percent of these showed the scintigraphic appearance of focal decrease in uptake. Among these 82, histological evidence of carcinoma (follicular, papillary or mixed) was seen in 31 cases (37.8%), a further 31 cases showed follicular adenoma while 3 had autoimmune thyroiditis and 8 showed simple cysts. We conclude the hypofunctioning solitary nodule without clinical evidence of malignancy need not always be cancerous but the incidence I have demonstrated is high enough to warrant surgery in all patients with a palpable single nodule with reduced isotope uptake.

99mTc‐MDP COMBINED BLOOD POOL AND BONE PHASE RADIONUCLIDE IMAGING IN PAPAIN‐INJECTED CARPAL JOINTS

Scintigraphic changes, i.e., increased activity, were induced by 1% papain, dissolved in phosphate‐buffered physiologic saline (pH 7.4), injected into one antebrachiocarpal joint in each of eight dogs. Scintigraphic evaluation was by the use of combined blood pool and bone phase scintigraphy of affected and normal carpi over a 28‐day period. The qualitative and quantitative scintigraphic appearance in injected carpal joints were very similar in both blood pool and bone phases. The clinical use of combined blood pool and bone phase scintigraphy to diagnose early inflammatory joint changes appears limited.

Evaluation of indium scintigraphy in patients with active inflammatory bowel disease.

Recent reports have indicated a possible role for 111Indium leucocyte scintigraphy in the management of patients with acute inflammatory bowel disease. Our experience with this technique in 15 patients (nine with ulcerative colitis, six with Crohn's disease) is described. Perfect agreement was not obtained between scintigraphic appearances and other conventional means in the assessment of extent of disease. Good correlation, however, was found between disease activity and recovery of labelled leucocytes in the faeces. While this latter finding could be used as an objective means of assessing response to therapy, it is concluded that conventional indium scintigraphy, using indium oxine-labelling of mixed leucocytes, is insufficiently reliable to replace usual methods for determining extent of disease in patients with inflammatory bowel disease.