Robert J. Cowan

Apparent complete lower esophageal sphincter relaxation in achalasia

Seven of 23 patients (30%) seen in 2 yr with clinical and radiologic manifestations of achalasia underwent esophageal manometry demonstrating aperistalsis but apparent complete lower esophageal sphincter (LES) relaxation. Detailed clinical and laboratory evaluation suggests these patients may represent an early stage of achalasia. Duration of dysphagia and weight loss were significantly less (p less than 0.05), whereas LES pressure was similar in the 7 patients compared with the 16 more traditional achalasia patients. Isotope retention during radionuclide esophageal solid-emptying studies showed intermediate delay in emptying between normal subjects and achalasia patients. The duration of LES relaxation in this group was significantly shorter (p less than 0.01) than in normal subjects. Although complete, sphincter relaxation in these patients is functionally inadequate and may be the result of this shortened duration. The small size of standard manometry catheters may also contribute to this confusing finding. Apparent complete LES relaxation may be seen during manometry in achalasia and should not exclude its diagnosis.

Mediastinal uptake of I-131 in a hiatal hernia mimicking recurrence of papillary thyroid carcinoma

I-131 is used to image patients diagnosed with papillary or follicular carcinoma of the thyroid after thyroidectomy to observe for metastatic disease or residual thyroid tissue. I-131 is excreted in gastric mucosa and is seen in the esophagus after the swallowing of saliva. The authors describe a patient in whom radiopharmaceutical activity in the mediastinum was subsequently shown to be due to a hiatal hernia.

Gastroesophageal scintigraphy: is it a sensitive screening test for gastroesophageal reflux disease?

Dynamic radionuclide imaging potentially offers a convenient, noninvasive technique for detecting gastroesophageal (GE) reflux disease. Initial studies suggested a high degree of sensitivity, although subsequent reports have been less encouraging. We sought to clarify this controversy by assessing the sensitivity of GE scintigraphy in 15 patients with severe esophagitis at endoscopy and 15 health volunteers. After acid loading, scintigraphy was performed in the basal state and after maneuvers (Valsalva, abdominal compression) which provoke GE reflux. Computer analysis permitted calculation of a reflux index for each maneuver. An index greater than 4% was considered a positive test. We found that the mean reflux index for the patients was significantly greater (p less than 0.01) than the healthy volunteers; 4.55 +/- 1.75% versus 0.42 +/- 0.11%, means +/- S.E.M. Only 30% of the patients had a reflux greater than 4%. Using data from our healthy volunteers, we redefined an abnormal reflux index as greater than 1.7%, but that only improved the test sensitivity to 60% and the specificity to 100%. Scintigraphy for reflux is primarily limited by the short duration of imaging. We cannot recommend GE scintigraphy as a useful screening test for reflux.

Efficacy of Radionuclide Scanning in Patients With Lung Cancer

Ninety-two patients with histologically proved carcinoma of the lung were studied retrospectively to determine the usefulness of liver, brain, and bone imaging in their examination and treatment. Occult metastatic liver disease was observed in two (5.3%) of 38 asymptomatic patients, while four (6.6%) of 58 neurologically intact patients had abnormal brain scans. Eight (13.6%) of 59 asymptomatic patients had metastatic bone disease. Seven (18.4%) of 38 patients with no clinical evidence of metastatic disease to liver, brain, or bone had at least one type of abnormal radionuclide study. More than half (52.5%) of the patients studied had at least one abnormal scan exclusive of symptoms. Radionuclide imaging is a useful procedure in the initial evaluation and subsequent management of lung cancer.

Value of the Routine Use of the Cerebral Dynamic Radioisotope Study

Abstract The results of 1,165 serial dynamic studies were reviewed. The routine addition of the dynamic study to the static image increased the detection of lesions by 33%. In patients with middle cerebral or carotid disease, the number of abnormal studies was doubled. Meningioma, arteriovenous malformation, and middle-cerebral-artery occlusion produced characteristic patterns on the dynamic study. Specific combinations of dynamic study and static image findings increased the certainty of diagnosis. Decreased perfusion was due to cerebrovascular disease eight times more often than to tumor. The combination of normal perfusion and a positive gamma camera image occurred three times as frequently with tumor as with cerebrovascular disease.

”Radioisotope Arteriography” as an Adjunct to the Brain Scan

The brain scan is now widely employed for the evaluation of patients with suspected intracranial lesions. It is a simple, safe, relatively accurate diagnostic procedure and may be used both to screen patients and to complement cerebral arteriography and air studies in the identification of intracranial lesions. Although not as accurate as the latter two procedures in the detection of intracranial pathology (1–3), the brain scan has the decided advantages of lower patient morbidity, better demonstration of the extent of the lesion, availability on an out-patient basis, and a simplicity that makes its repeated use practical in following the course of a disease. In spite of its value, the brain scan has two major disadvantages: (a) it fails to localize all intracranial lesions, particularly those related to occlusive vascular disease, and (b) a positive scan alone is not sufficient to accurately identify the etiology of the lesion (tumor vs. infarction, etc.). The introduction of the scintillation camera has...

Trauma to the brain and extracranial structures

Over the past 10 years there have been numerous reports in the literature on the value and limitations of the various radionuclide procedures in the investigation of patients following head trauma. 1–3 This review contains an amalgamation of the currently known information concerning the usefulness of these procedures in the different clinical entities that may result from trauma to the brain and extracranial structures. The intravenous cerebral dynamic study and the static brain image have successfully been employed in the diagnosis of patients with subdural hematomas, epidural hematomas, intracerebral hematomas, and contusions of the brain. Properly employed, these studies may be utilized as screening procedures, and in isolated incidences may provide the definitive diagnosis. The problems associated with positive static images as a result of skull and scalp trauma will also be considered. Radioisotope cisternography has also been found to be of clinical value in the localization of cerebrospinal fluid leaks resulting from trauma and in the evaluation of disturbed CSF flow following head injuries.

Radionuclide scanning in patients with advanced malignant melanoma

&NA; The results of liver, bone, and brain scans in 84 patients with recurrent or metastatic malignant melanoma were reviewed. The liver scan was initially positive in 18% (14/78) and ultimately in 32% (25/78). Serum alkaline phosphatase and lactic dehydrogenase were elevated in 92%. These patients ultimately developed positive liver scans, while convincing hepatomegaly was noted in only 44%. Bone scans were eventually positive in 33% (16/49), all of whom had pain. Brain scans were positive in 15% (10/65), all of whom had CNS symptoms. In asymptomatic patients, bone and brain scans only rarely disclosed occult lesions.

Evaluation of serum alkaline phosphatase determination in patients with positive bone scans

Results of serum alkaline phosphatase determinations (SAPD) were reviewed in 100 patients with positive bone scans from metastatic disease. Thirty‐eight per cent of these had normal SAPDs in spite of evidence of bone involvement on scans. Clinicians should not rely solely on the SAPD in evaluation of patients with suspected metastatic bone disease prior to radical treatment or in long‐term management of patients with malignant disease.

A potential false-positive posttherapy radioiodine scan secondary to I-131 excretion in perspiration.

A 40-year-old woman underwent 1-131 radioablation therapy after total thyroidectomy for follicular carcinoma. After dosing with 3700 mBq of I-131 sodium iodine, the initial post-therapy images revealed an unexpected site of increased activity in the posterior skull region. Careful evaluation raised the possibility of contamination by perspiration in her hair. Repeat images obtained after the patient washed no longer demonstrated the activity. This case illustrates the importance of awareness of minor routes of I-131 excretion when interpreting posttherapy images