Junctional parenchyma: revised definition of hypertrophic column of Bertin

The so-called hypertrophic column of Bertin is a normal variation and simply represents unresorbed polar parenchyma of one or both of the two subkidneys that fuse to form a normal kidney. It contains renal cortex, pyramids, and columns (septa) of Bertin. (Since all elements of the tissue are normal, that is, neither hypertrophic nor a displaced or embryonic rest, it is referred to as "junctional parenchyma.") When a masslike lesion is suspected at sonography or excretory urography, diagnosis of junctional parenchyma can be made with a high degree of certainty when sonography shows that the structure (a) is located between the overlapping portion of two renal sinus systems, (b) is bordered by a junctional parenchymal line and defect, (c) contains renal cortex, pyramids, and columns of Bertin, and (d) contains renal cortex that is continuous with the adjacent renal cortex of the same subkidney.

Use of an acoustic transponder for US visualization of biopsy needles

A 20-gauge Chiba needle with a stylet embedded with polyvinyldifluoride (PVDF), a polymer that acts as an acoustic-electric transducer, facilitated a variety of diagnostic and therapeutic ultrasound (US)-guided interventions in nine patients. PVDF receives acoustic energy from the US scanner and transmits an electrical signal through the stylet and a shielded cable to the scanner, which results in appearance of a bright echo on the monitor at the location of the needle tip.

Anatomic variations and abnormalities in the diaphragm seen with US

The authors report their experience with diaphragmatic structures that simulate intrahepatic masses at abdominal ultrasonography (US). In a series of 74 patients, diaphragmatic slips were the most common finding (34 patients). The slips could be differentiated from masses by scanning along their long axis to demonstrate elongated structures with multiple linear echoes. Scalloping of the diaphragm, associated with multiple slips, was seen in 10 patients. Partial eventration was found in 23. Inversion of a hemidiaphragm, caused by a large pleural effusion or intrathoracic mass, was seen in 13 patients. Pleural masses affecting the diaphragm were seen in 13 patients; focal hypertrophy of a diaphragmatic crus simulated a mass in three. Real-time US allowed the differentiation of diaphragmatic abnormalities from lesions.

Deposition of ultrafine aerosols in rat nasal molds

To evaluate the health effects of air pollutants on the respiratory tract, it is critical to determine the regional deposition of inhaled aerosols. Information on deposition of larger particles (greater than 0.2 microns) in the nasal passages of laboratory animals is available; the deposition fraction increases with increasing particle size. However, little deposition information is available for ultrafine particles of less than 0.2 microns. Three clear, plastic molds (models) of the nasal passages of F344/N rats, prepared from metal replica casts were used in these studies. Total deposition of ultrafine aerosols in the casts was determined by using a unidirectional flow system. The pressure drops measured in the casts were a function of flow rate to the power of 1.4-1.6, indicating that flow through the nasal passages has nonlaminar components. Deposition data were obtained by using monodisperse sodium chloride aerosols with particle sizes ranging from 0.2 to 0.005 microns, at inspiratory and expiratory flow rates of 200 to 600 ml/min. Similar deposition data were obtained for two of the casts studied. Deposition efficiency was greatest for the smallest particles, and decreased with increasing particle size and flow rate. At an inspiratory flow rate of 400 ml/min, which is comparable to the mean respiratory flow of an adult male F344 rat with a respiratory minute volume of 200 ml, deposition efficiencies reached 40 and 70% for 0.01- and 0.005-microns particles, respectively. These studies demonstrated that turbulent diffusional deposition was the dominant mechanism for uptake of ultrafine particles by the nasal passages.

Sonographic evaluation of portal hypertension in children

Portal hypertension, an expected consequence of cirrhosis, often has an insidious course in children. A noninvasive technique using abdominal sonography has been previously employed by several investigators as a means of diagnosing this condition. Their technique involves sonographically measuring the diameter of the lesser omentum, which increases as a result of engorged collaterals. In this communication, the method is successfully employed in two children, an infant in whom cirrhosis developed who eventually died from acquired immunodeficiency syndrome, and one whose portal hypertension was relieved after orthotopic liver transplantation. Although successful in these two instances, the theoretical basis on which this technique is based is critically evaluated. Anatomical relationships are reviewed that would caution sonographers who attempt to duplicate these studies. Modifications of the technique that will minimize potential false positive results are also discussed.

Deposition of cigarette smoke particles in the rat

The fractional deposition of cigarette smoke particles in the respiratory tracts of rats was studied. Male and female rats were conditioned in nose-only exposure tubes 25 min/day for 2 days, exposed to cigarette smoke at mass concentrations of 95 or 341 mg/m3, 25 min/day for 3 days, and then exposed to smoke at mass concentrations of 212 and 657 mg/m3, 25 min/day for 5 days. Mainstream cigarette smoke was generated by a modified Walton smoking machine from two 1R3 research cigarettes burned sequentially for each exposure. Deposition studies were conducted by placing the rats in plethysmograph tubes to allow respiratory minute volume measurements during exposure, then exposing them to [14C]dotriacontane-labeled cigarette smoke at mass concentrations of 202 or 624 mg/m3 for 25 min, using the same smoking machine. Size distribution, real-time concentration, and 14C activity of the smoke particles were determined using a multijet Mercer impactor, a real-time aerosol monitor, and filter samples, respectively. Immediately after the exposure, the rats were terminated to determine the distribution of the 14C. Individual lung lobes, trachea and lobar bronchi, head, larynx, kidneys, liver, gastrointestinal (GI) tract, blood, and depleted carcass of each rat were analyzed for 14C content. Results showed that the GI tract contained 16-31% of the total activity, indicating significant clearance from the large airways and nose to the GI tract during the exposure and during the 10-15 min between the cessation of the exposure and the removal of the organs. Total deposition of the inhaled 14C activity was 20.1 +/- 1.6% for both exposure concentrations. The intrapulmonary deposition fractions (lung lobes plus airways below the lobar bronchi) were 12.4 +/- 0.9 and 15.9 +/- 1.4% for concentrations of 202 and 624 mg/m3, respectively, suggesting a slight enhancement in upper airway deposition for animals exposed to the higher smoke concentration.

Lung retention and binding of [14C]-1-nitropyrene when inhaled by F344 rats as a pure aerosol or adsorbed to carbon black particles

1-Nitropyrene (NP), as found in the environment, is more typically associated with carbonaceous particles than found as an aerosol of the pure compound. To determine whether (and why) an association with particles resulted in prolonged lung retention of NP, rats were exposed to 14C-NP as a pure aerosol or adsorbed on carbon black particles. Total 14C retained in the lung was greater at all times from 0.5 h to 30 d after exposure to 14C-NP adsorbed to carbon black particles than after exposure to pure 14C-NP (p less than .05). The fraction of total 14C in lung bound to carbon black particles decreased steadily with time after exposure, indicating in vivo removal of NP from the particles. At 0.5 h after exposure, the fraction of the estimated deposited 14C that was covalently bound to lung macromolecules was twofold greater for NP adsorbed on carbon black than for pure NP. Covalently bound 14C in lungs increased with time after exposure to 14C-NP adsorbed to carbon black, reaching levels of approximately 1% of the deposited radioactivity at 7-30 d after exposure, whereas levels of covalently bound 14C declined with time after exposure to pure NP. Thus, at 30 d after exposure, the amount of 14C covalently bound to lung macromolecules was approximately 10-fold greater (p less than .05) in rats that inhaled 14C-NP adsorbed on carbon black particles than in rats that inhaled pure 14C-NP aerosols. These results suggest that association of NP with carbon black particles augments the interaction of reactive metabolites of NP with target macromolecules. This phenomenon is thought to be related to the slow release of NP from carbon black particles, and may augment the biological effects of inhaled NP when adsorbed on carbon black or similar particles in the environment.

Adrenal gland and nonrenal retroperitoneum

Ultrasound, as the initial cross-sectional imaging technique, confirmed the value of axial records. Although computerized tomography and possibly magnetic resonance offers better resolution, ultrasonography has the advantage of being less expensive, convenient, and highly portable. With these specific indications and reservations, ultrasonography of the adrenal and retroperitoneum has an accepted role in imaging.

The prevalence of hyperandrogenism in 109 consecutive female patients with diffuse alopecia

Endocrine dysfunction was studied in 109 consecutive female patients with moderate to severe alopecia, mostly of a diffuse pattern. The study included an evaluation of associated hirsutism and/or menstrual dysfunction, plasma hormonal measurements, and ultrasonography of the ovaries. A control group of 24 ovulatory, nonhirsute, nonalopecia individuals was also studied. Of the 109 patients, 70 (64.2%) had no clinical evidence of hirsutism or menstrual dysfunction. Two of 44 patients tested with cosyntropin (Cortrosyn) had 21-hydroxylase deficiency, whereas two other patients had hyperprolactinemia caused by pituitary tumors. Hyperandrogenism was defined as an increase in any of the plasma androgens (testosterone, non-sex hormone-binding globulin bound testosterone, dehydroepiandrosterone sulfate, androstenedione, or dihydrotestosterone) and was noted in 42 of the 109 patients studied (38.5%). Of these 42 patients, 11 were ovulatory with no evidence of clinical hirsutism, 13 were ovulatory and hirsute, and 18 had oligomenorrhea or amenorrhea with or without hirsutism with confirmatory evidence of polycystic ovarian disease. Patients with diffuse alopecia may demonstrate hyperandrogenism, even in the absence of hirsutism, oligomenorrhea, or amenorrhea. The most common endocrine disorder in this series of patients with diffuse alopecia was polycystic ovarian disease.

Amniotic sac development: ultrasound features of early pregnancy--the double bleb sign

The amniotic sac-embryo-yolk sac complex can be seen with ultrasonography (US) as two small blebs of almost equal size attached to the wall of the early gestational sac. We have called this the double bleb sign. Since the developing embryo and its cardiac pulsation are located between these two blebs, the size of an early embryo can be measured. The crown-rump length thus measured corresponds well to that described in embryologic textbooks, and an embryo as small as 2 mm (5 weeks 3 days) can be measured with use of this method. Three stages of development of the amniotic sac-embryo-yolk sac complex can be identified with US, and they are useful in dating the pregnancy. These three stages are 1, a simple double bleb, 2, a double bleb with a stalk, and 3, a double bleb with a separating yolk sac. As the amniotic sac enlarges, strands of echoes may be seen within the chorionic cavity and should be differentiated from amniotic bands, which may cause serious fetal abnormality. Separation of the amniotic from the chorionic membrane before the 13th week is normal but may be abnormal after the 17th week of gestation. Separation of the chorionic membrane from underlying decidua, however, is abnormal at any stage of pregnancy.

Deposition and retention patterns for 3-, 9-, and 15-micron latex microspheres inhaled by rats and guinea pigs

This study was designed to determine the deposition patterns and fate of large particles inhaled by two species of small laboratory animals during nose breathing. Rats and guinea pigs inhaled 3-, 9-, or 15 micron polystyrene latex microspheres labeled with 46Sc. Approximately 1.4% and 0.55% of the initial internally deposited body burden of 3-micron microspheres was in the alveolar region of the respiratory tract of rats and guinea pigs, respectively. None of the 9- or 15-micron microspheres were detected in the alveolar regions of the rats or guinea pigs. Ninety-five to 99% of the deposited microspheres cleared from these animals with biological half-times of 0.5-1.0 day. Most of the cleared radioactivity was in the feces. Approximations for long-term biological half-times for alveolar retention of the 3-micron microspheres were 63 days for rats and 83 days for guinea pigs. About 1% of the initial lung burden of 3-micron microspheres was translocated from lung to lung-associated lymph nodes in both species; none of the 9- or 15-micron microspheres were detected in those lymph nodes. Small fractions of the microspheres initially deposited in the airways of the head were retained with biological clearance half-times ranging from 9 to 350 days. Results from this study do not allow projections for deposition and retention patterns for similar particles inhaled by humans. Such projections must come from studies with humans, or from studies with animal species having deposition patterns for inhaled materials more comparable to those of humans.

Lack of correlation of ultrasonographically determined ovarian size with age, ponderal index, and hormonal factors in 45 patients with polycystic ovarian disease

An ultrasonographic study was performed on 45 patients with polycystic ovarian disease. These patients demonstrated hirsutism, menstrual disturbances, or infertility, as well as an increased LH/FSH ratio and/or evidence of hyperandrogenemia. Ovarian size was not correlated with age, Ponderal Index, serum testosterone, prolactin, androstenedione, dehydroepiandrosterone sulfate or LH/FSH ratio in the 45 subjects studied.

Polycystic ovarian disease: US features in 104 patients

Ultrasonographic (US) study was performed in 25 healthy women and 104 patients with polycystic ovarian disease (PCOD). Although the average size of ovaries in the PCOD patients was much larger than that of the healthy women, 29.7% of ovaries in the PCOD patients were normal in size. The shapes of the ovaries (roundness index) in PCOD patients were not different from those of the healthy women. There was no significant correlation between the size and shape of the ovaries. Bilaterally enlarged, globular-shaped ovaries were rare and usually asymmetric in size. The most important feature of PCOD on US scans is the bilaterally increased numbers of developing follicles (0.5-0.8 cm in size), usually more than five in each ovary. Although maturing follicles (1.5-2.9 cm) are much rarer in PCOD patients (13.5%) than in healthy women (36%), the incidences of follicular cysts (greater than 3 cm) was about the same in both.

Nose-only exposure system for inhalation exposures of rodents to large particles

A large-particle exposure system for small animals was designed, constructed and evaluated. The system was designed by incorporating a fluidized bed aerosol generator (FBG) and a nose-only exposure device to accommodate 40 small animals into a single unit. The system has four levels of exposure ports, each level having ten exposure ports radially positioned around the aerosol delivery components of the system. The aerosol generator produces aerosols that travel to the top of the system then downwards in order to be drawn past each animal's nose via vacuum ports immediately above the exposure ports. Nearly monodisperse polystyrene latex aerosols with nominal sizes of 3.0, 9.0 and 15.0 micron were generated as dry powders in an FBG with an inside diameter of 5 cm. During 60-min test runs, average aerosol mass concentrations up to 37 mg/m3 were achieved with less than 10% variation in mass concentration distribution throughout the unit.

Crossed fused renal ectopia: sonographic diagnosis

Five cases of crossed fused renal ectopia, all confirmed by either computed tomographic scan or intravenous urography, were diagnosed sonographically. The sonographic appearance of this entity consists of a characteristic anterior and/or posterior notch, difference in orientation of the 2 collecting systems in the fused kidneys, and absence of a kidney in the contralateral renal fossa, or elsewhere in the body, such as the pelvis. The inability to diagnose this condition correctly may lead to the misdiagnosis of a renal mass or infiltrative disease occupying the contralateral renal fossa. Computed tomographic scans will also identify the anomaly.

Intradecidual sign: a US criterion of early intrauterine pregnancy

The uterine cavity appears on sonograms as a linear echo, which is usually visible during early pregnancy and remains straight until the eighth to ninth week of gestation. The early gestational sac is not enveloped by two layers of decidua, as suggested by descriptions of the double decidual sac sign; the sac (or echogenic area of early implantation) is actually located within a markedly thickened decidua on one side of the uterine cavity. The combination of these two sonographic characteristics is called the "intradecidual sign." An early implantation of 25 days gestational age can be detected by the presence of the intradecidual sign, which is sooner than a gestational sac can be seen. The implantation site can also be located by means of the intradecidual sign. In a study of 36 patients with early intrauterine pregnancy and five with ectopic pregnancy, the intradecidual sign was more sensitive (91.7% vs. 63.9%) and specific (100% vs. 60%) than the double decidual sac sign in the detection of early intrauterine pregnancy.

Studies of the temporal and spatial distribution of aerosols in multi-tiered inhalation exposure chambers

Two multi-tiered whole body inhalation exposure chambers with nominal volumes of 1 m3 (H-1000) and 2 m3 (H-2000) were evaluated for their performance in terms of the temporal and spatial distribution of test aerosols within the chamber. Parameters investigated included chamber type, single-chamber-single-aerosol generator versus two-chamber-single-aerosol generator systems, chamber air supply and exhaust systems, particle size, and aerosol diluter type. Results indicated that: 1) particle size has an effect on chamber aerosol concentration distribution, with the larger particle resulting in a higher variation; 2) the single-chamber-single-generator system is more stable than the two-chamber-single-generator system; 3) the H-2000 chamber has a lower aerosol spatial variability than the H-1000 chamber; and 4) the aerosol distribution within the chamber could be improved with the use of a newly designed diluter.

Deposition, metabolism, and excretion of 1-[14C]nitropyrene and 1-[14C]nitropyrene coated on diesel exhaust particles as influenced by exposure concentration

Nitrated polycyclic aromatic hydrocarbons (nitro-PAH) have been detected in the environment, originating from sources such as diesel exhaust emissions and coal combustion fly ash. 1-Nitropyrene (NP) is a predominant mutagenic and carcinogenic nitro-PAH found in diesel exhaust emissions. Since inhalation of NP is a likely route of exposure in humans, it is important to determine the biological fate of inhaled NP both in its pure form and associated with particles. The purpose of this study was to determine the disposition of NP aerosols inhaled by rats. The studies described in this paper were designed to determine the deposition of [14C]NP over a range of exposure concentrations, identify the pathways and half-times for excretion of absorbed NP, and determine the distribution of inhaled NP and metabolites in tissues. Male F344 rats were exposed nose only to various concentrations of NP and NP coated on diesel exhaust particles (50-1100 ng/liter). The results indicate that, over the range of concentrations tested, pathways for excretion of [14C]NP equivalents in urine and feces were independent of the exposure concentration of NP, whether in its pure form or associated with diesel exhaust particles. In all cases, fecal excretion was the major route of elimination of [14C]NP equivalents, with about 2 times more excreted by this route than by urine. The fractional deposition of [14C]NP in the respiratory tract did not appear to be dependent on exposure concentration. Half-times for elimination of 14C in urine and feces were about 15 to 20 hr. In all exposures, 14C was widely distributed in the tissues examined. Analysis of the tissues for NP and its metabolites indicated that within 1 hr after exposure, greater than 90% of the 14C was NP metabolites. Lungs of rats exposed to [14C]NP coated on diesel exhaust particles contained nearly 5 times more 14C than lungs from rats exposed to pure aerosols of [14C]NP (148 vs 29 pmol/g lung) within 1 hr after exposure. This difference was increased to 80-fold at 94 hr after exposure (80 vs 1 pmol/g lung). Long-term clearance half-times of 14C from various tissues were similar. The results demonstrate that particle association of NP significantly alters the biological fate of inhaled NP.

Computed tomography and ultrasonography of the hemophilic pseudotumor and their use in surgical planning

Twenty-one hemophilic pseudotumors in 17 patients were evaluated radiologically to facilitate surgical planning. Plain radiography, angiography, intravenous urography, computerized tomography (CT), and ultrasonography (U/S) were the modalities used. CT proved to be the most efficient method in the detection of bone destruction and soft tissue lesions including additional daughter cysts. The combination of CT, intravenous urography, and angiography were used in pelvic pseudotumors, and that of CT and angiography for extremity pseudotumors, to determine the proper surgical approaches to the lesions. As a non-ionizing technique, U/S was usually preferable in visualizing soft tissue masses and, in sequential studies, to evaluate progress or recurrence of the lesion.