Reflux evaluation: correlation between pH results, esophagitis, esophageal dysmotility, patient age, and esophageal caliber

The purpose of this study was to correlate gastroesophageal reflux evaluated by 24-h pH study to esophageal motility, diameter of the esophagus and diaphragmatic hiatus, and patient age. We recorded radiographic findings from barium esophagrams in 91 patients (47 women, 44 men) with a mean age of 52 years (range 17-18 years), who had 24-h pH monitoring of the esophagus. All patients had one or more symptoms related to the upper aerodigestive system, and both studies were performed within 2 days of each other. The average diameters of the esophagus and hiatus were 24 mm and 19 mm respectively. The correlation coefficient (r) between patient age and diameter of the esophagus was -0.22. No correlation was found between the diameter of the hiatus and the size of the esophagus or patient age. Esophageal diameter is significantly wider in patients with esophagitis than in patients who have no esophagitis. Thirteen of 27 patients with absent primary peristalsis had abnormal pH results. The diameter of the esophagus may be affected by aging, but was not affected by the presence of dysmotility. The caliber of the hiatus was stable and was narrower than the diameter of the esophagus. The hiatus tended to be wider when esophagitis existed.

Complications of renal transplantation: evaluation with US and radionuclide imaging

Following renal transplantation, patients are often evaluated with ultrasonography (US) or radionuclide imaging to assess renal function and the presence of possible complications. Both modalities are inexpensive, noninvasive, and nonnephrotoxic. A basic understanding of the surgical techniques commonly used for renal transplantation is useful when imaging these patients in order to recognize complications and to direct further imaging or intervention. The most frequent complications of renal transplantation include perinephric fluid collections; decreased renal function; and abnormalities of the vasculature, collecting system, and renal parenchyma. Perinephric fluid collections are common following transplantation, and their clinical significance depends on the type, location, size, and growth of the fluid collection, features that are well-evaluated with US. Causes of diminished renal function include acute tubular necrosis, rejection, and toxicity from medications. Radionuclide imaging is the most useful modality for assessing renal function. Vascular complications of transplantation include occlusion or stenosis of the arterial or venous supply, arteriovenous fistulas, and pseudoaneurysms. Although the standard for evaluating these vascular complications is angiography, US is an excellent noninvasive method for screening. Other transplant complications such as abnormalities of the collecting system and renal parenchyma are well-evaluated with both radionuclide imaging and US.

Gallbladder stones: imaging and intervention

Imaging of the gallbladder for cholelithiasis and its complications has changed dramatically in recent decades along with expansion of interventional techniques related to the disease. Ultrasonography (US) is the method of choice for detection of gallstones. The characteristic US findings of gallstones are a highly reflective echo from the anterior surface of the gallstone, mobility of the gallstone on repositioning the patient, and marked posterior acoustic shadowing. Oral cholecystography remains an excellent method of gallstone detection, but its role has been limited due to the advantages of US. Most people with cholelithiasis will not experience symptoms or complications related to gallstones. When biliary colic does occur, it is typically caused by transient obstruction of the cystic duct by a stone. The primary imaging modality in suspected acute calculous cholecystitis is usually US or cholescintigraphy. Detection of gallstones alone does not permit a diagnosis of acute cholecystitis; however, secondary US findings provide more specific information. In detection of choledocholithiasis, endoscopic retrograde cholangiopancreatography and magnetic resonance cholangiopancreatography are superior to US. In certain clinical settings, interventional radiologic procedures have become an important alternative to surgery in the treatment of gallstones and their complications; techniques include percutaneous cholecystostomy and gallstone removal.

Endoscopy in acquired immunodeficiency syndrome patients with diarrhea and negative stool studies

BACKGROUND

Diarrhea is a frequent gastrointestinal symptom in patients with acquired immuno-deficiency syndrome (AIDS) and is a major source of morbidity and mortality. A stepwise diagnostic approach is often recommended to search for treatable causes. However, whether the stepwise diagnostic approach is adequate for planning treatment and whether specific treatment for infectious etiologies will affect the survival of patients with AIDS remain unknown.

METHODS

From March 1996 to September 1997, endoscopy was performed in AIDS patients with diarrhea, the etiology of which was not identified by noninvasive methods. Specific treatment was given according to the identified etiologies and symptomatic treatment was given for those without definite diagnosis. The clinical symptoms, signs, and duration of follow-up were recorded and survival patterns were analyzed.

RESULTS

Etiologic diagnoses were made in 26 of 40 patients (65%) who underwent endoscopic studies. Amebic colitis and cytomegalovirus colitis were the 2 leading causes of prolonged diarrhea in patients with AIDS. Thirty-five patients (87.5%) recovered after treatment. The difference in survival time after diarrhea between patients whose symptoms resolved after treatment and those who continued to have diarrhea was statistically significant (p < 0.001).

CONCLUSIONS

Endoscopic studies were helpful for the diagnosis of prolonged diarrhea in AIDS patients who had negative stool studies and did not respond to 2 weeks of empiric treatment. Specific treatment according to the results of endoscopy may improve survival in these patients.

FDG PET evaluation of head and neck cancer: value of imaging the thorax

BACKGROUND

Patients with primary tumors of the head and neck have been reported to have a high rate of synchronous primary tumors of the upper aerodigestive tract. This study was performed to determine whether inclusion of the thorax in the scan volume would be diagnostically useful for positron emission tomography (PET) with [F-18] fluorodeoxy-D-glucose (FDG) in patients with primary tumors of the head and neck.

METHODS

FDG PET scans from the midcranium to the diaphragm were obtained on 56 patients with a variety of head and neck tumors on initial examination before definitive therapy. PET findings in the chest were correlated with results of all other imaging studies, biopsy results, and clinical follow-up.

RESULTS

In nine studies (16%), areas of increased FDG uptake in the chest were seen and were judged to be tumors. Six of these probably were false-positive results, although one of these six may have been unconfirmed true positives. Of the three confirmed true-positive studies, two were obvious from other routine studies. In only one case did the PET study reveal a significant lesion not found by means of routine evaluation, resulting in a case-finding yield of 2%. If the unconfirmed possible true-positive results are included, the case-finding yield increases to 4%.

CONCLUSIONS

No compelling indication was seen for including the chest in PET studies of patients with head and neck cancer.

Treatment of recurrent Kaposi's sarcoma of an AIDS patient with weekly paclitaxel

Paclitaxel was recently recognized as an active chemotherapeutic agent for acquired immunodeficiency syndrome (AIDS)-associated Kaposi's sarcoma (KS). However, the best way to administer paclitaxel in AIDS-KS patients remains unknown. Herein, we reported an AIDS-associated KS patient whose disease progressed on the first-line chemotherapy with doxorubicin and bleomycin, but later responded well to weekly 1-hour infusion of 70 mg/m2 paclitaxel. It is particular noteworthy that this weekly dosing schedule resulted in almost negligible toxicities. The authors suggested a prospective study of weekly paclitaxel for AIDS-KS should be started as soon as possible.

Geographical differences in human herpesvirus 8 seroepidemiology: a survey of 1,201 individuals in Asia

Since the discovery of human herpesvirus 8 (HHV8) as a contributory cause of Kaposis sarcoma, the clinical role of this virus has been actively investigated. An understanding of HHV8 seroepidemiology is critical for the study of its pathogenesis within a specific environment. A sero-survey is described in Taiwan of 1,201 individuals ranging in age from under 1 year to over 70. Indirect immunofluorescence assay was used to determine antibody titers against both latent and lytic antigens of HHV8. The results indicate that very few individuals (3-4%) were exposed to HHV8 before 10 years of age. Infection rate peaked (19.2%) between the ages of 21 to 40. Females showed a slightly higher seroprevalence for HHV8 than males, but the difference was not statistically significant. Pregnancy did not correlate with increased HHV8 infection rate nor with augmented HHV8 antibody titers. It is concluded that HHV8 in Taiwan is predominantly an infectious agent for adults. In this geographical locale, HHV8 is similar to herpes simplex virus type 2 in its likely transmission occurring presumptively through sexual routes. However, the study also indicates that a smaller portion of HHV8-transmission could occur through nonsexual contacts.

Pulmonary infection in human immunodeficiency virus-infected patients in Taiwan

BACKGROUND

Pulmonary infection is a major cause of morbidity and mortality in human immunodeficiency virus (HIV)-infected patients.

METHODS

We conducted a retrospective analysis of the pathogens causing pulmonary infection in 272 HIV-infected patients admitted to a university hospital from January 1993 through December 1998.

RESULTS

A total of 158 (58%) patients had pulmonary complications, all but two of whom had acquired immunodeficiency syndrome (AIDS). There were 156 episodes of pulmonary infection, involving 124 patients. The most common pulmonary infection was Pneumocystis carinii pneumonia (PCP): 66 patients had 77 episodes of PCP, all of which occurred in patients with CD4+ lymphocyte counts below 0.2 x 10(9)/L (200/microL). Pulmonary tuberculosis (TB), diagnosed in 47 patients, was the second most common pulmonary infection. Twenty TB patients had open TB. HIV-infected patients who were immigrants from Southeast Asia (9/23, 39%) had a higher risk of developing pulmonary TB than nonimmigrants (38/249, 15%) (p = 0.004). Only one of 17 episodes of community-acquired bacterial pneumonia was caused by Streptococcus pneumoniae. Less common opportunistic pulmonary pathogens included cytomegalovirus (5 cases), Aspergillus species (3), Cryptococcus neoformans (3), Mycobacterium avium complex (2), Penicillium marneffei (1), Nocardia species (1), and Rhodococcus equi (1).

CONCLUSIONS

PCP and pulmonary TB are the two leading pulmonary infections in Taiwanese HIV/AIDS patients. These findings should be taken into consideration when developing management strategies and public health policies.

CT diagnosis of acute flank pain from urolithiasis

The use of noncontrast helical CT (NHCT) to assess patients with acute flank pain and hematuria for potential urinary tract stone disease was first reported in 1995. After several years of experience with the technique, sensitivity and specificity of NHCT has proven to be better than intravenous urography for evaluating ureteral stones. NHCT imaging findings for urinary calculi and the differential diagnosis are discussed in this article. Various extraurinary diseases found while using NHCT in searching for stone disease are addressed and illustrated. As experience with the use of NHCT has increased, clinicians have broadened the indications for this technique, which has a lower charge than standard CT, beyond the specific evaluation of urinary colic. This indication creep has increased the number of NHCT examinations ordered. It has also reduced the rate of stone positivity and increased the diagnostic yield for extraurinary disease.

Is it necessary to biopsy the obvious?

OBJECTIVE

The radiologist and oncologist are often confident that biopsy will confirm their suspicion of recurrent disease, but a biopsy is performed to confirm the histologic diagnosis before beginning or altering therapy. We have examined data to determine how often the biopsied lesion represents recurrent disease from the primary tumor or is an instance of new cancer, and whether recurrent disease can be predicted.

MATERIALS AND METHODS

We reviewed the medical and imaging records of 253 patients who underwent CT-guided biopsy of an abdominal or pelvic lesion between 1993 and 1996. Sixty-nine of the 253 patients had a previously diagnosed primary tumor and were being examined for possible tumor recurrence or metastasis. The images of these 69 patients were analyzed to determine if the pattern of disease was typical of recurrence or metastasis.

RESULTS

In 55 of the 69 patients, the pattern was judged to be typical of metastatic or recurrent disease. Biopsy confirmed this suspicion in all 55 patients. In 14 of the 69 patients, the pattern of spread was judged not to be typical of recurrence or metastasis. These 14 patients were found to have a new primary tumor (n = 4), benign processes (n = 2), and recurrences (n = 8).

CONCLUSION

Of the patients for whom radiographic findings suggested recurrence, we found no patients in whom a new primary tumor would have been missed if biopsy had been avoided. Data should now be acquired prospectively to determine whether it may be prudent to make treatment decisions on the basis of imaging findings alone, without histologic confirmation.

Immunoglobulin M and G immunoblots in the diagnosis of parvovirus B19 infection

BACKGROUND AND PURPOSE

To identify parvovirus B19 infection by means of immunoglobulin (Ig) G and IgM immunoblots among immunocompetent patients who tested negative or had low-titer B19 IgM antibodies in enzyme-linked immunosorbent assays (ELISA).

METHODS

Serum samples were obtained from 20 patients with parvovirus B19 infection. Another 130 study subjects presumed to be without B19 infection (40 medical personnel and 90 prisoners) were also included. All sera from the patient and study groups tested positive for IgG or IgM with ELISA and were further evaluated using the immunoblot method. Detection of B19 DNA by nested polymerase chain reaction (PCR) was also performed on IgG and IgM positive sera.

RESULTS

IgM immunoblots disclosed one false positive IgM ELISA result in the patient group and three false positive results in the study group. In the patient group, four patients were in the latter stage of antibody response to B19 infection as suggested by the low titer of anti-B19 IgM, incomplete IgM immunoblots, with only a weak viral capsid protein VP-N reaction band, and fading but still strong reaction bands on IgG immunoblots. Strong reaction bands on IgG immunoblots comparable to these four patients were found in three of the 130 study group sera. Furthermore, B19 DNA was detected in three of the four patients and one of the three study subjects by means of nested-PCR. A serum sample from one study subject showed strong IgG but no IgM reactivity to viral capsid protein VP2; nested PCR identified B19 DNA in this serum sample.

CONCLUSIONS

Immunoblots and nested PCR should be applied in the diagnosis of B19 infection for patients with low-titer anti-B19 IgM tested by means of ELISA. For diagnosis of B19 infections in certain clinical entities such as chronic arthritis of recent onset and hydrops fetalis, B19 IgM antibodies may have disappeared but B19 infection can still be recognized by the intensity of the reaction bands on IgG immunoblots. The correlation between chronic B19 infection and persistence of antilinear VP2 epitopes requires further study.

Invasive amoebiasis: an emerging parasitic disease in patients infected with HIV in an area endemic for amoebic infection

OBJECTIVES

To describe the incidence and presentations of invasive amoebiasis (IA) in patients with HIV infection in an area endemic for amoebic infection and to assess the role of the indirect haemagglutination (IHA) assay in the diagnosis of IA in HIV-infected patients.

DESIGN

Retrospective study of 18 cases of IA and HIV infection.

SETTING

A university hospital, the largest centre for management of HIV-associated complications in Taiwan.

METHODS

Medical, microbiological and histopathological records of 296 HIV-infected patients and serological data of IHA assay of 126 HIV-infected patients were reviewed to identify cases of IA from 23 June 1994 to 31 March 1999. An IHA titre > or = 1 : 128 was considered positive. Clinical characteristics of HIV-infected patients with IA and without IA were compared.

RESULTS

Eighteen of the 296 patients (6.1%) with HIV infection were diagnosed with IA: 12 patients were diagnosed with definite IA and six with probable IA. The clinical manifestations included amoebic colitis (13 patients), amoebic liver abscess (nine), both colitis and abscess (four), and pleural effusion (two). IA was the initial presentation of HIV infection in nine patients. Co-infection with other enteric pathogens was diagnosed in six patients with IA. Compared with the 161 patients without IA who were newly diagnosed with HIV infection, the nine patients with IA had a higher median CD4+ lymphocyte count (202 x 10(6)/l versus 33 x 10(6)/l; P = 0.0017), were less likely to be diagnosed with AIDS (55.6% versus 85.4%; P = 0.039), and had fewer concurrent AIDS-defining illnesses (median number 0 versus 2; P = 0.003). Estimated mean survival duration was not significantly different between the two groups (597 days versus 611 days). Fourteen out of 126 patients (11.1%) had an IHA titre > or = 1 : 128. Of the 18 patients diagnosed with IA, 13 had a titre > or = 1 : 128. The sensitivity of IHA assay in the diagnosis of IA was 72.2% (13 out of 18) and the specificity was 99.1% (107 out of 108). The positive predictive value of IHA test for IA of this patient population was 92.9% (13 out of 14) whereas the negative predictive value was 95.5% (107 out of 112).

CONCLUSION

IA is an increasingly important parasitic disease among patients with HIV infection in Taiwan. IHA assay has a good specificity and high negative predictive value in diagnosis of IA.

Trends in the use of unenhanced helical CT for acute urinary colic

OBJECTIVE

Unenhanced helical CT for urolithiasis detection is a limited CT examination that was designed specifically for the detection of urolithiasis. The purpose of this study was to repeat a prior study to assess whether clinicians had broadened the indications and changed the yield and findings of unenhanced helical CT.

MATERIALS AND METHODS

One hundred consecutive patients with suspected renal colic or flank pain referred for unenhanced helical CT were selected for this study. We reviewed the original radiographic reports for each patient and recorded the presence of ureteral calculi. Other urinary abnormalities and extraurinary lesions were also recorded and compared with the results of the previous study.

RESULTS

In this study, 56% of the patients who underwent unenhanced helical CT had symptoms of urinary colic, and 44% of patients had unspecified flank pain, compared with 100% of patients with symptoms of urinary colic 1 year earlier. The sensitivity and specificity of unenhanced helical CT in detecting ureteral calculi were 96% and 99%, respectively. Ureteral calculi were identified in only 28% of the patients versus 49% of patients (p < .01) 1 year earlier. Extraurinary lesions were identified in 45% of the patients versus 16% (p < .01) 1 year before.

CONCLUSION

As clinicians developed familiarity with this technique, the indications for performance of unenhanced helical CT were expanded with a consequent reduction in the rate of detection of stone disease and identification of an increased number of extraurinary lesions, which suggests a demand for emergency abdominal CT studies.

Genetic variation at nine STR loci in populations from the Philippines and Thailand living in Taiwan

In order to apply a set of nine STR loci and the amelogenin locus in forensic testing, we have performed a population study on individuals from the Philippines and Thailand living in Taiwan (273 Philippine and 146 Thai individuals were typed by commercially available kits and an automated sequencer). A total of 73 alleles for all systems for both populations could be observed in these two populations. No new intermediate fragments were found. Allele frequencies showed no deviation from Hardy-Weinberg equilibrium. The mean exclusion power (MEP) ranged from 0.327 (TPOX) to 0.706 (FGA), the discriminating power (DP) ranged from 0.790 (TPOX) to 0.963 (FGA) for Philippinos, MEP ranged from 0.247 (TPOX) to 0.723 (FGA), DP ranged from 0.761 (TPOX) to 0.968 (FGA) for Thais, the combined MEP is > 0.9988 and the combined DP is > 0.9999999993 for both Philippinos and Thais.

Radiographic anatomy: multimedia interactive instructional software on CD-ROM

OBJECTIVE

We wanted to create a filmless radiographic anatomy curriculum, a didactic software with a digital image database on CD-ROM for first-year medical students.

CONCLUSION

We created a CD-ROM that includes an introduction, radiographic anatomy tutorial, and interactive questions. Additional features include Boolean text searching, links to related images, and Internet accessibility. The software can be updated.

Sonohysterography: the next step in the evaluation of the abnormal endometrium

Sonohysterography is a simple ultrasound (US) procedure that may be used to evaluate the endometrium. The technique involves placement of a 5-F catheter into the endometrial canal with subsequent instillation of sterile saline solution under US guidance. Fifty patients successfully underwent sonohysterography because of apparent abnormal endometrial thickening at transvaginal US, a nonspecific finding. Patients tolerated this procedure well, and no complications were encountered. In the 39 patients who proved to have endometrial pathologic conditions, sonohysterography demonstrated focal processes (polyps, carcinoma, hamartoma) in 15, diffuse processes (hyperplasia, secretory endometrium) in 21, and both focal and diffuse pathologic conditions in three. If a focal process can be delineated, a visually directed biopsy may be necessary. However, if the process is diffuse, a blind aspiration biopsy may be performed on an outpatient basis. In the majority of patients, the diffuse or focal nature of the disease could not be predicted on the basis of initial transvaginal US. Because sonohysterography allows distinction between diffuse and focal abnormalities, it provides physicians with a cost-effective way to plan the next step in case management.

The CT appearance of pleural and extrapleural disease in lymphoma

OBJECTIVE

Pleural effusions in patients with lymphoma that are assumed to be related to malignancy are attributed to either lymphatic obstruction by tumour with resultant decreased clearance of pleural fluid, or direct tumour involvement of the pleura. The purpose of our study was to determine how often pleural or extrapleural disease was detected by computed tomography (CT) of patients with pleural effusions and primary or recurrent lymphoma.

METHODS AND MATERIALS

We reviewed CT examinations showing evidence of pleural effusion in 61 patients with a diagnosis of primary or recurrent lymphoma and no history of other systemic disorders, including infection. The study population consisted of patients with non-Hodgkin's lymphoma (n = 44) or Hodgkin's disease (n = 17); both primary disease (n = 11) and recurrent disease (n = 50) were represented. Each CT examination was evaluated for the presence of disease involving the visceral and parietal pleura and extrapleural space, mediastinal adenopathy, and pulmonary parenchymal disease.

RESULTS

Fourteen patients (23%) (nine with non-Hodgkin's lymphoma and five with Hodgkin's disease) had parietal pleural disease (thickening or nodules). Eighteen patients (30%) (14 with non-Hodgkin's lymphoma, four with Hodgkin's disease) had tumour or enlarged lymph nodes in the extrapleural space. Forty-three patients (70%) had mediastinal lymphadenopathy. Patients who received intravenous contrast did not have evidence of visceral pleural abnormalities or underlying pulmonary parenchymal disease.

CONCLUSION

Forty-one percent of the patients with lymphoma and pleural effusions had CT evidence of pleural and/or extrapleural disease. The majority of the patients with extrapleural disease had adjacent posterior mediastinal disease.

Focal delivery during direct infusion to brain: role of flow rate, catheter diameter, and tissue mechanics

Direct interstitial infusion is a technique capable of delivering agents over both small and large dimensions of brain tissue. However, at a sufficiently high volumetric inflow rate, backflow along the catheter shaft may occur and compromise delivery. A scaling relationship for the finite backflow distance along this catheter in pure gray matter (x(m)) has been determined from a mathematical model based on Stokes flow, Darcy flow in porous media, and elastic deformation of the brain tissue: x(m) = constant Q(o)(3)R(4)r(c)(4)G(-3)mu(-1) 1/5 [corrected] = volumetric inflow rate, R = tissue hydraulic resistance, r(c) = catheter radius, G = shear modulus, and mu = viscosity). This implies that backflow is minimized by the use of small diameter catheters and that a fixed (minimal) backflow distance may be maintained by offsetting an increase in flow rate with a similar decrease in catheter radius. Generally, backflow is avoided in rat gray matter with a 32-gauge catheter operating below 0.5 microliter/min. An extension of the scaling relationship to include brain size in the resistance term leads to the finding that absolute backflow distance obtained with a given catheter and inflow rate is weakly affected by the depth of catheter tip placement and, thus, brain size. Finally, an extension of the model to describe catheter passage through a white matter layer before terminating in the gray has been shown to account for observed percentages of albumin in the corpus callosum after a 4-microliter infusion of the compound to rat striatum over a range of volumetric inflow rates.

Pattern of defervescence in response to anti-tuberculosis therapy in patients with extrapulmonary tuberculosis and advanced human immunodeficiency virus infection

The pattern of fever response to empiric anti-tuberculosis therapy in patients with tuberculosis (TB) and human immunodeficiency virus (HIV) infection, and the relationship between fever response patterns and anti-TB drug susceptibility profiles of Mycobacterium tuberculosis isolates are rarely described. In this study, we evaluated the fever responses to a four-drug anti-TB regimen in 26 HIV-infected patients with culture-proven extrapulmonary TB, and compared the results with those in 12 patients with disseminated Mycobacterium avium complex (DMAC) infection treated with a clarithromycin-containing regimen. The CD4 lymphocyte counts did not differ significantly between TB and DMAC patients (26 x 10(6)/L in TB patients vs 5 x 10(6)/L in DMAC patients). Drug susceptibility data were available for 22 patients with TB. Most TB patients had rapid defervescence after initiation of anti-TB therapy. Fever resolved within 1 week in 85% (22/26) of patients, including three of six (50%) with multidrug-resistant (MDR) TB. The median duration of fever in patients with drug-susceptible TB was similar to that in patients with drug-resistant TB (3 vs 4 days, p = 0.33). However, patients with MDR-TB were more likely than those with non-MDR TB to have fevers lasting longer than 1 week after initiating anti-TB therapy (3/6 vs 1/16, p = 0.046). Only 17% (2/12) of the patients with DMAC infection became afebrile within 1 week of beginning anti-MAC therapy (p < 0.001 vs those with TB). Our observations suggest that in HIV-infected patients with advanced immunosuppression, anti-TB regimens achieve significantly faster defervescence in TB patients than do anti-MAC regimens in DMAC patients. Rapid defervescence in patients with TB does not necessarily indicate that TB isolates are not MDR strains.

Radiographic measurement of prevertebral soft tissue thickness on lateral radiographs of the neck

PURPOSE

The prevertebral soft tissue measurement is commonly used for assessing prevertebral pathology such as abscesses or hematomas after injury. Very few references concerning the ratio of retrotracheal thickness to C5 diameter are available in the literature. The purpose of this study was to measure the normal soft tissue thickness at the C5 level of the neck and to establish the normal ratio of retrotracheal soft tissue thickness to the diameter of C5 for daily use.

DESIGN AND PATIENTS

We measured soft tissue thickness in the neck of 54 normal subjects and calculated the mean and standard deviation.

RESULTS AND CONCLUSION

Using mean plus one standard deviation the maximum retrocricoid soft tissue thickness was 0.7xC5 diameter and maximum retrotracheal thickness was 1.0xC5 diameter. Soft tissue thickness that exceeds this limit must be studied further for signs of potential disease.

[Analysis of 50 cases of sexual dysfunction]

Fifty cases of male sexual dysfunction were analyzed in order to investigate the incidence and causes of the erectile dysfunction in the different injuries. The results showed that the incidence of erectile dysfunction of the patients with brevic fracture and urethra injury is 62.50%, main caused by the damage of pudendal nervous and arterial system. The incidence in the patients with the spinal fracture and light spinal cord injury is 50%, caused by the damage of nervous system. The erection in the 17 cases of the patients with only one testis injury is normal. Two cases with bilateral testis injury have suffered from erectile dysfunction.