Normal anatomy and limitations in CT interpretation of lymph node disease

The CT appearance of normal retroperitoneal lymph nodes has been described. In many instances the structures are too small to be identified. other retroperitoneal structures, such as collapsed bowel loops, vessels, and other perirenal structures, may simulate the presence of nodes. CT is of great benefit in disease with bulky tumors, such as non-Hodgkin's lymphoma, testicular tumors, etc. Its usefulness is much more limited in disease that may have extensive nodal involvement but no significant enlargement of the nodes. The accuracy of CT scanning in Hodgkin's disease and in many instances of genitourinary tumors is questioned, and we submit that further studies are needed to establish the reliability of this mode of examination.

Subxiphoid two-dimensional imaging of the interatrial septum in infants and neonates with congenital heart disease

The interatrial septum (IAS) was studied by subxiphoid two-dimensional echocardiography (S2DE) in 88 infants under 12 months of age who weighed 1.2-9.1 kg. The IAS was adequately displayed in 87 of 88 patients. The morphology, presence and localization of defects in the IAS were evaluated by S2DE and retrospectively related to the findings at cardiac catheterization. In seven patients with no interatrial communication at cardiac catheterization, the IAS was straight, with an area of central thinning corresponding to the veil-like cover of the septum primum over the foramen ovale. The morphology of the IAS with a stretched, patent foramen ovale (56 patients) indicated the coexistence of a right or left ventricular volume or pressure overload, and was readily distinguishable from the IAS with a secundum type communication (13 patients). In patients with a stretched, patent foramen ovale and left ventricular overload lesions, the IAS was a nearly homogenous, curvilinear structure bowing into the right atrium, with a small area of septal dropout at the superior rim of the septum primum. In the presence of right ventricular overload lesions, the central defect of the foramen ovale was associated with a redundant flap valve of the septum primum billowing into the left atrium. In secundum type communications, the centrally located defect represented a deficiency rather than a redundancy of the septum primum. Balloon atrial septostomy (BAS) in 17 patients produced a secundum-type defect bordered by the flail remnants of the torn septum primum. Blalock-Hanlon septectomy (two patients) resulted in a large, posterior, sinus venosus-type communication which incorporated the preexisting BAS. Ostium primum defects (seven patients) were distinguished from the secundum lesions by their eccentric position in the IAS adjacent to the atrioventricular ring.

Low attenuation lesions in the midline posterior fossa: differential diagnosis

A wide variety of cystic appearing or low attenuation lesions in the midline posterior fossa can so closely resemble one another as to render specific histologic diagnosis from CT scans alone fraught with error. Absorption coefficients often overlap and are too nonspecific to infer consistently accurate histologic diagnosis. It is virtually impossible to separate cystic from noncystic, benign from malignant, and neoplastic from non-neoplastic lesions by absorption coefficients alone.

Gossypiboma--the problem of the retained surgical sponge

Commonly used surgical sponges and appliances all have standardized, readily recognized opaque markers visible on radiographs. When these markers are identified on postoperative radiographs, they should be assumed to represent retained surgical sponges or appliances. With the rare exception of thoracotomy dressings, these marked materials are seldom, if ever, used as external bandaging materials. AP and lateral radiographs should provide an immediate answer as to the location of any retained surgical device. The early recognition of these retained surgical sponges should eliminate most complications related to their presence.

Prophylactic treatment of Rocky Mountain spotted fever

Prophylactic treatment of Rocky Mountain spotted fever with a single dose of oxytetracycline was investigated in guinea pigs. Disease was prevented when treatment was administered shortly before expected onset. Relapses occurred when treatment preceded expected onset by 48 h or more.

Echocardiographic evaluation of valvar and shunt lesions in children

An evaluation of valvar and shunt lesions in children is directed toward appraising the need for, and timing of, surgical repair or palliation as well as demonstrating the cardiac anatomy which will, in turn, direct the type of surgery to be chosen. Static dimension measurements as well as dynamic measurements of wall velocity and time intervals are atraumatic and easily obtained values that increase our sensitivity to early cardiac decompensation. Contrast studies add both functional and anatomic information. Although one-dimensional time-motion scanning remains an invaluable source of anatomic detail, two-dimensional imaging has made positional information clearer and more reliable. The combined use of these three techniques offers the most complete evaluation of children with volume and pressure overload lesions.

Retractile mesenteritis: initial presentation as colonic obstruction

Retroperitoneal fibrosis has been associated with a variety of sclerosing diseases. Among these is the variant known as retractile mesenteritis, which involves predominantly the mesentery of the small intestine and associated vessels; involvement of the mesocolon and the colon is less frequent. Two patients with a dominating clinical picture of colonic obstruction are described. The radiographic presentations were similar and should serve to remind radiologists and clinicians of this entity.

Tympanometric diagnosis of middle ear effusions

A review of medical records of unselected children in whom the otoscopic diagnosis of middle ear effusion was uncertain, showed that tympanometry resolved the diagnostic uncertainty with an accuracy of 88 per cent for the prediction of a dry middle ear and an accuracy of 85 per cent for predicting fluid in the middle ear. Tympanometry itself gave inconclusive findings in II per cent of cases. Tympanometry can greatly reduce the need for diagnostic aspiration of the middle ear.

Pathogenesis of infection with Rickettsia rickettsii in the dog: a disease model for Rocky Mountain spotted fever

Dogs inoculated with Rickettsia rickettsii developed a clinical syndrome ranging in severity from a mild febrile exanthema to death within six days after inoculation. The severity of the disease appeared to be dose-related, and the signs were comparable to R. rickettsii infection in humans on a clinical and hematological basis. Dogs were rickettsemic for 10 to 14 days after infection. In most animals the level of rickettsemia was greater than or equal to 10(2.5) guinea pig intraperitoneal 50% infectious doses (GPID50). Infected dogs responded serologically as determined by indirect fluorescent antibody methods and were protected when challenged six to 12 months later with 10(7.0) GPID50 of the homologous strain of R. rickettsii. The monocyte culture technique was successfully used for the detection of rickettsemia, and the results compared favorably with those obtained by the guinea pig inoculation method of isolation.

Studies on the pathogenesis of Rickettsia rickettsii in the dog: clinical and clinicopathologic changes of experimental infection

Beagle dogs inoculated with the agent of Rocky Mountain spotted fever, Rickettsia rickettsii, developed a clinical syndrome that extended from febrile exanthema to death and appeared to be dose related. Infected dogs were anorectic and lethargic and developed cutaneous lesions characteristic of Rocky Mountain spotted fever, including petechia, ecchymosis, edema, and necrosis. Hematologic changes after inoculation included anemia, leukopenia proceeding to leukocytosis, and thrombocytopenia. Changes in blood chemistry values included increases in serum alkaline phosphatase and cholesterol, and hyponatremia and hypochloremia. The prominent histopathologic change was necrotizing vasculitis. The canine disease is comparable with human Rocky Mountain spotted fever on a clinical, hematologic, biochemical, and pathologic basis, and may provide a model system for this disease in man. The results suggest the dog may be involved in the epidemiology of R rickettsii infections.

Echocardiographic features of congenital left ventricular inflow obstruction

The echocardiographic features of congenital left ventricular inflow obstruction are described in six patients. The echocardiograms in two patients with cor triatriatum were distinguished by normal mitral valve motion and an abnormal echo within the left atrium. In two patients with supravalvar mitral ring, in addition to abnormal mitral valve motion, an abnormal echo, presumably originating from the obstructive membrane, was located between the anterior and posterior mitral leaflets. In two cases of parachute mitral valve, mitral valve motion was abnormal. In one of these cases there were multiple mitral valve echoes similar to those found in supravalvar mitral ring. The echocardiographic identification of an obstructive membrane within the left atrium is difficult because of the occurrence of artifacts. However, membranes may be identified if careful scanning techniques are employed in patients in whom left ventricular inflow obstruction is suspected. The echocardiogram is useful in detecting mitral valve abnormalities in these patients and is valuable in cases where mitral valve replacement is contemplated.

Cancer of the larynx in Hull and the surrounding area of East Yorkshire

A study of all patients with cancer of the larynx in a population of 449,430 over ten years shows that supraglottic and epilaryngeal cancer has an almost equal incidence to glottic cancer. There is a relationship between urbanization and the incidence of cancer of the larynx, and between cancer of the larynx and bronchogenic carcinoma. A policy of radiotherapy with surgery held in reserve for supraglottic and epilaryngeal cancer failed at a general hospital, for reasons that have been discussed. Primary surgery is required for most cases of supraglottic and epilaryngeal cancer. Radiotherapy with surgery held in reserve is the most appropriate treatment for the great majority of glottic cancers. When radiotherapy failed to cure the disease palliation was achieved in only a small minority of the cases.

Overriding tricuspid valve: echocardiographic and angiocardiographic features

Eight cases are presented in which the diagnosis of overriding of the tricuspid valve was made during life and the electrocardiographic, echocardiographic and angiographic features of the defect are presented. Four of the patients had dextrotransposition of the great arteries, three had normally related great arteries and one had corrected transposition. In each case there was hypoplasia of the right ventricle and a ventricular septal defect of the atrioventricular (A-V) canal type. The electrocardiogram in the cases with d-transposition was characterized by diminished right ventricular forces, left ventricular forces, left ventricular hypertrophy and a superior leftward frontal plane axis. The echocardiogram in seven cases demonstrated a septal leaflet of the tricuspid valve opening posterior to the septum into the left ventricle. In four cases the anterior leaflet of the tricuspid valve was shown crossing the plane of the interventricular septum as it opened in diastole. The diagnosis in five cases was made angiographically by a left ventricular injection in the left anterior oblique projection. In this view the septum was viewed tangentially and in diastole the negative silhouette of the tricuspid valve was seen straddling the interventricular septum. The presence of an overriding tricuspid valve can greatly complicate repair of intracardiac defects. The diagnosis of this A-V valve anomaly can be accurately made with the use of echocardiography and selective left ventricular angiography.

Echocardiographic assessment of cor pulmonale in cystic fibrosis

The early clinical recognition and assessment of cor pulmonale are frequently difficult. To evaluate the usefulness of echocardiographic measurement of right ventricular dimension and septal motion in assessing cor pulmonale, we studied 94 patients with cystic fibrosis of varying severity. There was a significant relationship between increasing right ventricular dimension index (RVDI) and (1) decreasing clinical score, vital capacity, forced expiratory volume in one second (FEV1), and maximal midexpiratory flow rate (MMFR); and (2) increasing residual volume and thoracic gas volume. There was no correlation between right ventricular dimension index and PaO2. These findings were supported by electrocardiogram and pathologic evidence of right ventricular involvement. Abnormal septal motion was observed more frequently in patients with severe obstructive airway disease as measured by decreased vital capacity, FEV1, and MMFR. The data show that there is echocardiographic evidence of mild right ventricular enlargement and/or hypertrophy much earlier in the course of cystic fibrosis than previously suspected and that the echocardiogram is a useful tool in the evaluation of cor pulmonale in patients with cystic fibrosis.

Abnormalities of regional lung function associated with ventricular septal defect and pulmonary artery band

Xenon-133 ventilation-perfusion scans and technetium-99m angiocardiograms were performed 47 times in 34 patients. All patients had ventricular septal defect (VSD), 17 with pulmonary artery band (PAB), 6 with isolated VSD, 4 with pulmonary valvar stenosis (PS), and 7 with transposition of the great arteries (d-TGA), VSD, and PAB. Patients with VSD had slightly depressed ventilation fraction of the left lung and slightly elevated perfusion fraction of the left lung, both before and after closure of the VSD. Patients with VSD and PAB had slightly depressed ventilation fraction of the left lung but perfusion fraction of the left lung that was either markedly elevated or markedly depressed. After closure of VSD and removal of PAB the perfusion abnormality returned toward normal in some patients but remained abnormal in most. The findings were similar in most patients with d-TGA. Ventilation-perfusion ratio was nearly normal in patients with VSD alone, both before and after closure of VSD. In patients with VSD with PAB the severe abnormality of ventilation-perfusion ratio returned toward normal after corrective operation but did not reach normal. There was no abnormality of distribution of perfusion along the cephalocaudal axis of the lung with the patient supine.

Liquid chromatography of clindamycin 2-phosphate on triethylaminoethyl cellulose

The separation of clindamycin 2-phosphate from clindamycin 3-phosphate, clindamycin 4-phosphate, clindamycin B 2-phosphate, and lincomycin 2-phosphate was achieved by liquid chromatography on triethylaminoethyl cellulose using a 254-nm monitor. The compounds have low molar absorptivities at 254 nm (smaller than 17), and UV detection is made possible by the high capacity support triethylaminoethyl cellulose. Linear peak height response versus concentration allows rapid quantitation of clindamycin 2-phosphate.