Pocket-Sized Versus Conventional Ultrasound for Detecting Fatty Infiltration of the Liver.

BACKGROUND AND AIMS: The high prevalence of nonalcoholic fatty liver disease (NAFLD) in the general population warrants determining whether pocket-sized ultrasound devices (PoCUS) might serve as point-of-care screening for NAFLD in busy office practices. METHODS: One hundred adult subjects undergoing conventional abdominal ultrasound (US) examinations for various indications were screened by PoCUS immediately prior to the conventional US procedure. The PoCUS examination only assessed the presence or absence of excess fat. Assessment of other liver pathology was not performed. Investigators (conventional US: an experienced radiologist and PoCUS: a general internist recently trained in the use of PoCUS) were blinded to the results of the alternative imaging. RESULTS: Forty patients (40%) had fatty infiltration of the liver on both conventional US and PoCUS, and 49 (49%) were negative by both modalities. A consensus was reached in two of the 11 remaining subjects with initially discrepant results. The overall sensitivity and specificity of PoCUS relative to conventional US were 91% and 88%, respectively. CONCLUSIONS: These findings support the use of PoCUS by a trained physician for point-of-care screening of patients at risk for NAFLD.

PCR assessment of HSV-1 corneal infection in animals treated with rose bengal and lissamine green B.

PURPOSE: In vivo, the ophthalmic dye rose bengal displays profound antiviral effects against herpes simplex virus (HSV)-1, thus limiting its utility in diagnosis of epithelial keratitis when used before viral culture is performed. In contrast, lissamine green B does not possess significant antiviral activity in vivo. To determine whether polymerase chain reaction (PCR) could successfully detect HSV-1 DNA in ocular samples that have been exposed to ophthalmic dyes, animal models were used to observe the presence of infectious HSV-1 and viral DNA in eyes treated with rose bengal or lissamine green B. METHODS: Animals were bilaterally infected with HSV-1 strain H129, and at daily intervals up to 16 days post infection (dpi) rose bengal or lissamine green B was instilled in the left eyes. The right eyes were not treated with dyes. Swabs of the dye-treated and untreated eyes were assayed by PCR for viral infectivity by culture and the presence of DNA specific for a fragment of the HSV-1 DNA polymerase gene. RESULTS: A statistically equivalent number of samples from lissamine green B-treated and untreated eyes were positive by both viral culture and PCR. In contrast, rose bengal significantly decreased the infectious virus present in ocular secretions. A total of 44% and 78% of the rose bengal-treated and untreated eye samples, respectively, were positive by culture from 1 through 16 dpi. PCR was more sensitive than culture for detection of HSV-1 in rose bengal-treated eyes, in that 74% of rose bengal-treated samples were positive by PCR compared with 44% that were positive by culture during the 16-day period studied. It was also noted that both rose bengal and lissamine green B treatments slightly prolonged the period during which viral DNA was detectable in ocular secretions by PCR, possibly because the singlet oxygen produced by these photoreactive dyes compromised ocular cellular, humoral, and nonspecific immune factors allowing viral DNA to persist for slightly longer periods. CONCLUSIONS: PCR can successfully detect HSV-1 DNA in ocular samples that are culture negative and contain rose bengal or lissamine green B. Visualization of ocular epithelial defects with lissamine green B does not interfere with detection of infectious virus or HSV-1 DNA.

Diagnosis and management of oral lichen planus.

OLP has many clinical presentations. Some lesions of OLP require no treatment. Some must be managed for 20 years or more. The differential diagnosis of OLP is difficult and varied. Dermatologists should consider consultation with a dentist or specialist in oral medicine for diagnosis and management of lesions of OLP.

Interpretation of chemically created periapical lesions using direct digital imaging.

Perchloric acid (70%) was used to create simulated periapical lesions in tooth sockets of 15 dentate cadaver jaw specimens. Using the Trophy USA direct digital radiographic system, linear images were captured at selected time intervals after initial acid application and altered by contrast reversal, pseudocolor enhancement, and two forms of histogram equalization. The 525 total images were randomized for display on a computer monitor for evaluation by five endodontists. Images were evaluated twice by each rater, with viewings 1 to 2 wk apart. Statistical analysis determined interrater variability, intrarater reproducibility, and the relative merits of each enhancement technique. At 8, 12, 16, and 24 h after acid application, both techniques of histogram equalization yielded a statistically significant improvement over reverse contrast in perception of periapical patholais. Linear and pseudocolor-enhanced images were also significantly more diagnostic than reverse contrast at 12, 16, and 24 h. Intrarater reproducibility showed moderate agreement, but analysis showed only a fair level of interrater agreement.

Evaluation of the bond strength of dentin bonding agents used to seal resected root apices.

A number of improved dentin bonding agents have recently become available, but have not been evaluated on apical radicular dentin. The purpose of this study was to compare the tensile bond strengths of four adhesive resins on resected root ends before and after blood contamination. Forty single-rooted human incisors were cleaned and shaped and obturated. The apical 3 mm was then resected at a 45-degree angle, bonded, and tested for tensile bond strengths using an Instron machine. The bonding systems evaluated included Prisma Universal Bond 3, Scotchbond MultiPurpose Dental Adhesive, Amalgambond, and All Bond 2. All bonding systems were then covered with Prisma APH light-cure composite resin. Results indicated that the bond strengths of the blood contaminated groups were significantly less than those of the control groups, except in the case of Amalgambond where no significant difference was noted. When the surface was contaminated with blood, Prisma Universal Bond 3 had significantly lower bond strengths, whereas Amalgambond had significantly higher bond strengths than the other subgroups.

Interpretation of chemically created lesions using direct digital imaging.

This study compared conventional radiography to digital imaging in detecting chemically created lesions. Six human cadaver jaw specimens were used. A 70% perchloric acid solution was used to create lesions on the buccal cortical plate of each specimen. Digital imaging and conventional images were created after progressing time increments; each increment represented a more advanced lesion. The images were randomly evaluated by five evaluators. This study concluded: (i) when no lesion existed, there was no significant difference in digital imaging or conventional radiography in early detection; (ii) at 12 and 24 h, digital imaging demonstrated lesions significantly earlier than conventional radiography (p = 0.0001); (iii) no difference could be found between imaging techniques at 36 h and thereafter; and (iv) there were no significant differences in the various RadioVisioGraphy enhancement settings used at any of the time points examined.

Interpretation of periapical lesions using RadioVisioGraphy.

Density and gray-scale changes in radiographs are important visual features the clinician uses to evaluate changes in bone pattern. With the advent of a new direct digital radiology system, RadioVisioGraphy (RVG), the controlled adjustment of contrast is now possible. The purpose of this study was to compare RVG's diagnostic potential for detecting periapical lesions with that of conventional radiography. Lesions were created in human cadaver specimens and radiographed conventionally and with RVG. Images were evaluated by three endodontists. Results were: (a) when no lesion existed, conventional radiographs were more diagnostic than RVG at a significance level at p < or = 0.05; (b) when lesions were enlarged to involve lamina dura and medullary bone, RVG was superior at p < or = 0.05; and (c) no difference was found between conventional radiography and RVG when the lesion involved cortical bone.

Interpretation of endodontic file lengths using RadioVisiography.

The purpose of this investigation was to compare RadioVisioGraphy (RVG) imaging with conventional radiography in determining endodontic file length adjustment. Human cadaver sections with first or second molars were used. Files were inserted into canals at randomly selected lengths, from 4 mm short of the radiographic apex to 3 mm beyond. Radiographs and RVG images were evaluated to determine the adjustment needed to place the file 0.5 mm from the radiographic apex. Results showed no significant difference in the ability of endodontists to make accurate file length adjustments using conventional radiography versus RVG. In this study, it was found that: (a) accurate file length adjustments can be made from an image two times larger than the actual tooth; (b) RVG is not significantly better than conventional radiography; and (c) if both methods are available, RVG is preferred because of the significant reduction in radiation dose.

Presurgical tomographic assessment for dental implants. 1. A modified imaging technique.

A modified technique for presurgical evaluation of intraosseous implant placement using linear tomography has been developed. The simplified technique is applicable to tomographic systems equipped with a cephalometric head positioner (cephalostat) and a fiberoptic positioning light system. It provides precise cross-sectional images for the assessment of bone morphology and associated anatomic structures. This technique is more comfortable for patients who are unable to tolerate the positioning of submentovertex projections used to estimate horizontal angulation of the head position and to determine the depth of radiographic cut. Instead, the positioning light and casts are used to make these two determinations.

The role of the venous system in the abdominal flap of the rat.

The abdominal flap of the rat has become a popular model with investigators. Recently, researchers have been reporting survival of skin flaps with varying blood supplies. We studied the viability of skin flaps on a consistent model with varied blood supply. An 8 x 9 cm flap was raised in 40 male Sprague-Dawley rats. The viability of the flaps could be studied in 25 rats. The survival of a pedicled flap based on the left inferior epigastric artery and vein was compared with that of a pedicled flap with enhanced venous drainage. The survival of a venous flap based on the paired inferior epigastric veins and the paired long thoracic veins was compared with that of an arterialized venous flap. A composite graft was used as a control for all groups. A qualitatively improved survival was found in the pedicled venous-enhanced group (66 percent) compared with the pedicled flaps (56 percent) (p > 0.05). An improved survival was found in the arterialized venous flap (57 percent) compared with the venous flap (40 percent) (p < 0.05). All flaps had improved survival compared with the composite graft (0.6 percent) (p < 0.05).

Clinical and radiographic features of the lacrimo-auriculo-dento-digital syndrome.

Lacrimo-auriculo-dento-digital syndrome is an autosomal dominant malformation complex that affects craniofacial structures including the teeth and salivary glands. There have been several cases of this syndrome reported to date. A family with three affected members is presented. In addition to several of the clinical manifestations of lacrimo-auriculo-dento-digital syndrome, these subjects also show previously unreported radiographic features of the syndrome as demonstrated by panoramic radiographic examination and corrected axis linear tomography of the temporomandibular joints.

Oral mucosal injury caused by denture cleanser tablets: a case report.

A case of chemical injury to the oral mucosa that resulted in obstructive sialadenitis of the submandibular glands is presented. The injury occurred when a patient chewed, swished, and expectorated an immersion-type denture-cleansing tablet attempting to clean a fixed bridge. The literature is reviewed for similar oral mucosal injury caused by improper use of denture-cleansing products. Suggestions for the prevention of such injuries are made.

Characteristics of an oral and maxillofacial radiology department. Report of the ad hoc Department Characteristics Committee of the American Academy of Oral and Maxillofacial Radiology.

Oral and maxillofacial radiology is a dynamic and multifaceted discipline that plays a critical role in patient care, the education of general dentists and dental specialists, and the academic health of the dental school. Diagnostic and treatment advances in temporomandibular joint disorders (TMD), implants trauma and orthognathic surgery, and craniofacial abnormalities depend heavily on conventional and advanced imaging techniques. Oral and maxillofacial radiology contributes to the education of pre- and post-doctoral dental students with respect to biomedical and clinical knowledge, cognitive and psychomotor skills, and the professional and ethical values necessary to properly prescribe, obtain, and interpret radiographs. The development of an active and successful oral and maxillofacial radiology department, division, or section requires the committment of institutional resources. This document may serve as a guide to dental schools committed to excellence in oral and maxillofacial radiology.

Imaging using solid-state detectors.

Whether they know it or not, many dentists already have adapted solid-state imaging devices into their offices in the form of an intraoral or video-camera system for esthetic dentistry and patient education. These dentists own charge-coupled devices. The technology, however, had been accepted well before instruction in the imaging principles was available. With the addition of digital radiographic systems, the dentist who is "buying into" these contemporary imaging devices must become familiar with the imaging principles behind them, and with the applications of these systems to dental problems or tasks. This article attempts to bring the dentist "up to speed" with this technology and discusses its present and future applications. In this way, the clinician will move past the simple "show-and-tell" stage or patient education and begin to see the true potential of imaging for more accurate detection of disease, for quantitating changes in that disease through time, and for making better clinical decisions about patient treatment.

Advances in diagnostic imaging in dentistry.

Advances in optical and x-ray imaging will affect dramatically the practice of dentistry in the next decade. "Hard copy" of these images will be on thermographic paper from videoprinters as well as x-ray film. Reconstruction of images in both (two and three dimensions) will allow better visualization of disease processes and allow quantification of disease changes over time, thus assisting the treatment planning decisions of the dentist and improving patient care. Some of these innovations are here, others are in the research and development stage. All dentists eventually will use these techniques routinely.

Intraoral detectors. CCD, CMOS, TFT, and other devices.

The first real-time intraoral detectors were introduced in 1997. Since then, charge-coupled device sensors have dramatically improved. The spatial and gray-scale resolution has increased and the dimensions of the sensitive areas are now comparable to those of conventional film. More recently, complementary metal oxide semiconductors were introduced. This technology offers the potential of integration, manufacturability, and low costs. Digital radiographic technology has matured and clinicians should adopt the systems and invest the time and effort to master them.

The future of digital imaging in dentistry.

Digital radiographic imaging in dentistry has matured. All the reasons dentists have cited for keeping conventional, film-based systems have been refuted: cost, sensors, storage, and training are not issues. There are many reasons to switch to digital. This article outlines external factors that dentists may not have considered that will influence the way they conduct business in their offices related to radiographic imaging. The evidence points to the inevitable adoption of digital imaging systems.

Disorders of the maxillary sinus.

The maxillary sinuses often are visualized on oral and maxillofacial radiographs, and the dentist should be able to interpret any signs of disease in the area. In addition, disorders of the sinuses may result in symptoms that the patient interprets to be of dental origin. Conversely, dental diseases may influence the radiographic appearance of the sinuses. This article reviews the radiographic signs of common sinus disorders to help the clinician accurately assess the patient.

Implant radiology.

Implant procedures are becoming commonplace in the dental office. Root form implants are placed by the general dentist, and no longer remain in the realm of dental specialists. Pre- and postsurgical radiographic evaluation of endosseous or root form implants is central to the success of the procedure. This article reviews the applications and limitations of available imaging modalities--from intraoral radiographs to computed tomography imaging--to help the clinician decide which imaging technique is best suited to the task of radiographic evaluation of implants and implant sites.

Magnetic resonance imaging in dentistry.

MR imaging has found a place in the imaging sciences. These images are unique in that no ionizing radiation is used, the same tissues may or may not have different appearances with different machine settings, a unique set of terms is used to describe the findings in the images, and these findings can be analyzed with the view of obtaining more diagnostic information not readily available with any other imaging modality. Cases have been presented to help demonstrate differences in T1-weighted and T2-weighted sequences as well as the value of contrast material. Additionally, plain film and CT views were included so that they may be contrasted with the MR images. The role and application of CT versus MR imaging has been further discussed and illustrated by Nortjé and van Rensburg. A typical temporomandibular joint case has also been presented. In the future, it is hoped that clinicians will refer more patients for MR imaging so that diagnoses can be made more accurately with analytic software.