Staphylococcal esophagitis causing giant ulcers

A 29-year-old woman with Hodgkin disease developed odynophagia while receiving chemotherapy. Large esophageal ulcers due to staphylococcal infection of the mucosa were visualized by endoscopy and radiography. This unusual bacterial esophagitis represents another potential cause of giant esophageal ulcerations.

Treatment of renal transplant ureteral complications by percutaneous techniques

From January 1985 to October 1990, 487 adult renal transplantations were performed at our institution. Of 16 ureteral complications noted 15 were initially managed with percutaneous nephrostomy. Of the 8 complications that occurred during the last 2 years 5 resolved on percutaneous nephrostomy and stenting, or stenting with dilation alone. We conclude that percutaneous nephrostomy is indicated as an initial step in the diagnosis and treatment of urological transplant complications, and that it allows for nonoperative resolution of many of these complications.

Acute renal obstruction: evaluation with intrarenal duplex Doppler and conventional US

To evaluate duplex Doppler ultrasound (US) in acute renal obstruction, bilateral intrarenal Doppler US was performed in 23 patients with unilateral renal obstruction (proved by means of intravenous urography) of 36 hours duration or less. A mean renal resistive index (RI) was calculated for each obstructed and normal contralateral kidney and compared with findings on conventional US scans. The mean RI in the obstructed kidneys was elevated (.77 +/- .07 [standard deviation]) and was higher than the mean RI in the normal contralateral kidney (.60 +/- .04) (P < .001). RIs in the obstructed kidneys were as follows: .75 or greater in 15 kidneys, .70-.74 (mild RI elevation) in five kidneys (but > or = .10 higher than the RI in the normal contralateral kidney), and less than .70 in three kidneys (two of these three patients had pyelosinus extravasation and one patient had clinical obstruction for only 4-5 hours). RI elevation occurred before collecting-system dilatation in four patients (17%). RI elevation occurs by 6 hours of clinical acute renal obstruction and may precede pyelocaliectasis. Renal duplex Doppler US contributes useful clinical information, especially when US is the first modality used to evaluate acute renal colic.

Signal-to-noise measures for magnetic resonance imagers

The signal-to-noise ratio (SNR) in magnetic resonance imaging represents one of the system operating variables that must be determined both for evaluating the performance of different imaging protocols on a particular machine, and for monitoring machine performance as part of a routine quality control (QC) program. Utilizing a phantom and set of automated analysis programs currently under development, this study evaluated several ways of measuring image signal and noise and demonstrated the importance of utilizing measured voxel volumes as opposed to nominal volumes in the calculation of SNR. The NEMA proposed standard for SNR is compared with several other SNR measures and is recommended as the measure to be used in routine SNR reporting. The importance of utilizing other SNR measures in addition to the NEMA proposed standard for routine QC is discussed.

Complications of continuous ambulatory peritoneal dialysis: evaluation with CT peritoneography

OBJECTIVE

Patients on continuous ambulatory peritoneal dialysis are frequently referred for radiologic evaluation of complications related to the dialysis. We studied the value of CT peritoneography in evaluating these complications. CT peritoneography is a technique in which CT scans are obtained after dialysis fluid containing iodinated contrast material is infused into the peritoneal cavity through the dialysis catheter.

MATERIALS AND METHODS

Sixty consecutive CT studies performed on 48 patients during a 5-year period were retrospectively analyzed. In each case (with two exceptions), the patient had clinical findings suggesting a complication related to peritoneal dialysis. Each study was reviewed for evidence of dialysate leaks, hernias, unopacified fluid collections, and peritoneal adhesions. The patients' medical records also were reviewed to determine the resulting therapy and outcome.

RESULTS

Twenty-nine dialysate leaks were detected on 25 examinations: 15 were along the catheter tunnel, 10 were at the site of a previous surgical incision, two were at a previous catheter site, and two were from an undetermined site (catheter tunnel suspected in both cases). Loculated, unopacified peritoneal fluid collections were present on seven examinations. Adhesions limiting dialysate distribution were shown on five examinations. Five abdominal wall hernias and two inguinal hernias were detected. Overall, at least one abnormality related to continuous ambulatory peritoneal dialysis was shown on 40 (67%) of 60 studies. In 29 (73%) of these cases, clinical management was changed.

CONCLUSION

CT peritoneography is useful for evaluating complications commonly encountered in patients on continuous ambulatory peritoneal dialysis.

Intranasal midazolam as a sedative for children during laceration repair

We performed a retrospective chart review to determine the onset, duration, safety, and clinical sedative effects of 0.2 to 0.5 mg/kg intranasal midazolam in young children during laceration repair. Of 408 children treated for lacerations during an 8-month period, 42 (10%) received intranasal midazolam. Documentation was adequate for detailed analysis in 40 cases. Data are reported as mean +/- standard deviation and the frequency with 95% confidence limit (CL) estimates. The mean age of the study population was 32 +/- 9 months (range 12 months to 6 years), and the mean body mass was 14.5 +/- 3 kg. Topical or injected local anesthesia was used in 37 cases. Overall, 73% (CL 56% to 85%) of the children achieved adequate sedation. However, those receiving 0.2 to 0.29 mg/kg had adequate sedation in only 27% (CL 6% to 60%) of the cases compared with 80% (CL 52% to 95%) and 100% (CL 79% to 100%) when 0.3 to 0.39 and 0.4 to 0.5 mg/kg respectively were administered. When achieved, sedation occurred within 12 +/- 4 minutes, recovery occurred at 41 +/- 9 minutes, and discharge occurred at 56 +/- 11 minutes. No vomiting or clinically significant oxygen desaturation (defined as a drop of > 4% or to < 91%) was observed. We conclude that intranasal midazolam is a safe and effective sedative for laceration repair under local anesthesia in preschool-aged children. We recommend a dose of 0.3 to 0.5 mg/kg, with treatment failure less likely after 0.4 to 0.5 mg/kg compared with less than 0.3 mg/kg.

Delayed biliary drainage is common in asymptomatic post-cholecystectomy volunteers

A commonly used diagnostic criterion for sphincter of Oddi dysfunction is delayed drainage of contrast media from the bile ducts at endoscopic retrograde cholangiography (ERC), which is defined as the persistence of contrast greater than 45 min after injection. We performed ERC in 11 asymptomatic post-cholecystectomy volunteers for the purpose of evaluating biliary drainage time. In an attempt to more accurately quantify emptying, concomitant scintigraphy was performed at the time of ERC and contrast drainage. Sufficient contrast mixed with technetium-99m sulfur colloid to completely fill out the intra-hepatic tree was injected (mean volume, 9 ml) and the volunteers remained in the prone position during imaging. The length of time from cholecystectomy, bile duct size, volume of contrast injected, and scintigraphic T1/2s did not correlate with drainage time at ERC. At 45 min after injection the degree of residual contrast filling was scored as: empty in three volunteers, almost empty in one, one-fourth full in 5, and one-half full in two. Therefore, 7 of the 11 asymptomatic volunteers (63%) had delayed drainage. Even if more stringent criteria for delayed drainage were used (ducts one-half filled), 2 of the 11 (18%) had abnormal drainage. The frequent occurrence of delayed drainage in these asymptomatic post-cholecystectomy volunteers challenges the validity of the 45-min delayed drainage criterion for sphincter of Oddi dysfunction.

Superelastic guide-wire snare for removal of foreign bodies from the urinary tract

A superelastic guide wire was used (after failure of other methods) as a loop snare to retrieve a foreign body from the ureter in three patients. In vitro comparison of the expansion capability of the superelastic guide wire and that of the standard retrieval wire showed that the superelastic wire forms larger loops within an elastic space. Also, because of less frictional resistance and its ability to be formed into stiffer loops, the superelastic wire resists kinking and is easier to manipulate than the standard wire.

Experimental analysis of T1 imaging with a single-scan, multiple-point, inversion-recovery technique

Look and Locker's single-scan, multiple-point, T1 determination technique modified for imaging applications was evaluated experimentally for its accuracy and reliability with respect to the pulse sequence parameters, in particular, to the interpulse delay, tD, and the tip angle, alpha. T1 imaging experiments were performed with a 0.5-T imaging system on a phantom which consisted of an array of vials containing 2% agarose gels doped with various amount of Mn2+ using different combinations of the parameter set (tD, alpha). T1 results obtained with this technique were compared with those measured by a conventional inversion-recovery procedure using the same spectrometer. Strategic choice of pulse sequence parameters to minimize experimental errors and the criteria for these choices will be discussed.

Renal dysfunction in hepatic disease: early identification with renal duplex Doppler US in patients who undergo liver transplantation

To improve early detection of renal dysfunction in patients who undergo liver transplantation, a prospective study was performed with intrarenal duplex Doppler sonography before and after liver transplantation in 42 patients. The duplex Doppler findings were compared with multiple clinical and laboratory findings; patients were grouped on the basis of preoperative renal resistive index (RI) and serum creatinine level. The mean initial renal RI was elevated (.73 +/- .07 [standard deviation]); after transplantation, it was lower (.60 +/- .06) (P less than .001). Thirty-six patients had a normal serum creatinine level at the preoperative Doppler examination. Patients with an elevated renal RI (n = 19) had a greater chance of subsequent renal dysfunction (P less than .001), hemodialysis (P less than .01), longer stays in the intensive care unit (P less than .05), and longer hospital stays after surgery (P less than .05) than those with a normal renal RI (n = 17). In 34 patients the RI fell 10% or more after surgery and none died, whereas five of eight patients (62%) whose RI fell less than 10% died. Doppler analysis enabled identification of patients without azotemia whose course of disease before and after surgery was similar to that of patients with clinically recognized renal disease.

Magnetic resonance imaging during intracavitary gynecologic brachytherapy

The cases of three patients, two with Stage III-B and one with Stage II-B carcinoma of the cervix, are cited to illustrate specific advantages of magnetic resonance (MR) imaging over computed tomography (CT) during intracavitary gynecologic brachytherapy. CT and MR were performed during the first of two intracavitary implants. To obtain artifact-free images with the intracavitary implant in place, a CT- and MR-compatible Fletcher system applicator was used. Although CT failed to differentiate the cervical tumor clearly from surrounding tissues, the area of pathology could be identified on MR by comparing the T1-weighted (T1W) and T2-weighted (T2W) images. Cervical tumors typically exhibit low-signal intensity on T1W and high-signal intensity on T2W scans, whereas paracervical soft tissues demonstrate high intensity on both T1W and T2W images. This contrast permits the size, location, and paracervical involvement of the tumor to be defined by MR. Multiplanar MR images obtained during the patients' intracavitary brachytherapy help demonstrate the actual anatomic relationship between the tumor and the applicator. Isodose distributions displayed on these images show that, in two cases, the tumor margin extended beyond the prescribed isodose line. Thus, MR may prove to be a clinically useful reference during intracavitary brachytherapy for ascertaining radiation dose to actual tumor volume.

Transitional cell carcinoma of the bladder: patterns of recurrence after cystectomy as determined by CT

CT scans have been recommended for examination of patients at risk for recurrent transitional cell carcinoma after cystectomy. For CT to be useful in this regard, the location and type of recurrences must be known, so that appropriate scans can be made. Therefore, we retrospectively studied CT scans in 27 postcystectomy patients with recurrent transitional cell carcinoma of the bladder to identify the type and location of the recurrent disease. Recurrence was documented by biopsy in 18 patients and by progression of disease shown on serial CT scans in nine patients. All 27 patients had pelvic CT, and 23 had concomitant abdominal CT. Tumor recurred at the cystectomy site in 10 (37%) of 27 patients, pelvic adenopathy was present in 18 (67%) of 27 patients, and retroperitoneal adenopathy was present in 13 (57%) of 23 patients. Tumor recurrence at the cystectomy site was associated with pelvic adenopathy in seven of 10 patients, and the cystectomy site was the solitary site of disease in the remaining three patients. Conversely, in 11 of 18 patients with pelvic adenopathy no recurrence was seen at the cystectomy site. Combined retroperitoneal and pelvic adenopathy was identified in 11 of 23 patients, but two patients had retroperitoneal lymphadenopathy as their only site of recurrence. Hepatic metastases were seen in seven (30%) of 23 patients; six of these seven patients had metastases elsewhere. In four of five patients in whom underestimation of recurrent disease occurred, the deep pelvis and/or deep perineal space were involved. Our results show that the pelvis is the most common site for recurrence. Cystectomy site or retroperitoneal nodal recurrences are usually accompanied by pelvic adenopathy, but the converse is not as common. Our findings of deep perineal and isolated abdominal recurrences indicate that proper protocol for CT follow-up of the postcystectomy patient should include abdominal scans and scans through the perineum.

Diagnostic usefulness of post-void film in intravenous urogram

A survey was sent to urologists to assess their subjective evaluation of the post-void film in the intravenous urogram (IVU). Most of the urologists believed that the post-void film should be a routine part of all IVUs, particularly in men over forty years of age, and estimated that the film contributed useful information in 30 percent of cases. One hundred fifty IVUs were reviewed to assess the actual value of the post-void film in 119 different patients. In these patients, the postvoid film was seen to give unique information not available by history or films of the filled bladder in only 3 percent of the cases. Therefore, we conclude the post-void film should not be a routine part of every IVU, and should be obtained on an as-needed basis only.

CT findings in tuboovarian abscess

As there are little data in the radiologic literature regarding the CT appearance of and the associated findings of tuboovarian abscesses (TOA), we retrospectively reviewed CT from seven patients with nine TOAs. They were bilateral in two patients and unilateral in the remaining five. The most common appearance of these abscesses was that of a somewhat tubular septated cystic pelvic mass with uniform wall thickness and with loss of fat planes between the mass and the adjacent pelvic organs (usually the uterus when present). Ipsilateral ureterectasis was also seen in four of nine lesions. Although these findings are not specific for TOA, they should be considered when pelvic masses having the above configuration are seen on CT.

Traumatic pneumoperitoneum. Implications of computed tomography diagnosis

Pneumoperitoneum detected on plain radiographs following blunt abdominal trauma is nearly pathognomonic of bowel perforation and usually mandates exploratory laparotomy. To determine the significance of computed tomography (CT)-detected pneumoperitoneum, we reviewed the clinical records and imaging studies of all trauma patients in our hospital over a seven-year period whose abdominal CT scans showed free intraperitoneal gas. Patients who had penetrating injuries or peritoneal lavage prior to CT were excluded. Of the 18 patients who met these inclusion criteria, surgically confirmed bowel injury was found in only four (22%). In the remaining 14 patients, no evidence of gastrointestinal perforation was found by exploratory laparotomy (2 patients), diagnostic peritoneal lavage (4 patients), GI studies and clinical follow-up (6 patients), or clinical follow-up alone (5 patients). Seven patients had a pneumothorax as a possible cause for pneumoperitoneum. Two additional patients were on mechanical ventilation. Unlike pneumoperitoneum seen on plain film, CT-detected pneumoperitoneum is not pathognomonic of bowel perforation. While laparotomy is not mandatory in the non-surgically explored patient, close clinical observation is essential, and additional diagnostic tests such as peritoneal lavage or radiographic contrast studies can be beneficial to confirm the absence of intestinal injury.

Staging relationships and outcome in early stage testicular cancer: a report from the Testicular Cancer Intergroup Study

The Testicular Cancer Center Intergroup Study entered surgically staged patients with nonseminomatous tumor and metastases limited to the regional lymph nodes into a previously reported cooperative trial of immediate versus delayed therapy for positive retroperitoneal node disease. Patients with negative nodes (stage I) were placed in an observation registry with specified treatment strategy upon relapse. Of 264 stage I cancer patients 27 (10.2%) had recurrence: 5 of these 27 patients died after recurrence of the testicular malignancies, while 4 other nontumor-related deaths have occurred. Pre-lymphadenectomy staging characteristics observed to predict significantly node positivity are the results of radiological examinations, presence of tumor invasion, vascular invasion and tumor histology. In a multiple logistic regression analysis with these variables, misclassification still occurs in more than a fourth of the patients. Future refinements in diagnosis may allow for better prediction of these patients at risk to have positive lymph nodes and ultimately recurrence. Presently, if assessment of nodal involvement is the objective, noninvasive procedures are not an adequate substitute for surgical staging with modified lymphadenectomy.

Stones and infection in renal caliceal diverticula: treatment with percutaneous procedures

Percutaneous treatment of symptomatic caliceal diverticula has expanded the application of uroradiologic intervention. To assess the safety and efficacy of these procedures, we have reviewed our experience with percutaneous management of 12 symptomatic caliceal diverticula, 10 with stones and two infected. Nine stone-bearing diverticula were punctured directly with subsequent tract dilatation, nephroscopic stone extraction, and cavity obliteration (six with fulguration and drainage and three with drainage alone). One case was approached indirectly by puncturing a distant calix, dilating the diverticular neck, and flushing the stones into the collecting system for extraction. This cavity was not treated. Two infected diverticula were punctured directly for drainage and obliteration (one by fulguration and one by tetracycline sclerosis). Complete stone extractions were accomplished in all 10 cases. In eight with clinical follow-up ranging from 4 months to 6 years, one stone has recurred and seven patients are asymptomatic. Follow-up urograms were available in eight of 10 patients in whom cavity obliteration was attempted; in six (75%) of eight, nonvisualization of the diverticulum indicated successful obliteration. Only one major complication (urinoma requiring drainage) occurred. We conclude that percutaneous procedures are safe and effective in treating infected or stone-bearing caliceal diverticula. Direct diverticular puncture for access and diverticular fulguration for cavity obliteration is our preferred technique.

Acute renal failure: possible role of duplex Doppler US in distinction between acute prerenal failure and acute tubular necrosis

Ultrasonography (US) of the native kidneys is commonly requested for acute renal failure (ARF), although in most cases the examination results are negative. To detect changes in the Doppler waveform associated with ARF and determine whether Doppler US can provide significant diagnostic information not available with standard US, 91 patients with ARF were studied to determine a mean resistive index (RI) for each patient. Forty-six patients had acute tubular necrosis (ATN) with a mean RI +/- 1 standard deviation of .85 +/- .06, which was significantly higher than the mean RI of .67 +/- .09 in 30 patients with prerenal ARF (P less than .01). Fifteen patients had ARF due to non-ATN intrinsic renal disease (mean RI, .74 +/- .13). An elevated RI (greater than or equal to .75) occurred in 91% of patients with ATN versus only 20% of patients with prerenal azotemia. Patients with severe liver disease (hepatorenal syndrome) are a subset of those with prerenal ARF that accounted for most of the elevated RIs in this group. The study demonstrates that intrarenal Doppler US allows detection of changes associated with ARF far more often than standard US. More important, Doppler US may be helpful in distinguishing ATN from prerenal azotemia.

Calretinin and calbindin in the retina of the developing chick

Calretinin and calbindin-D28k are two calcium-binding proteins that are present in largely different sets of nerve cells in the central nervous system. Their appearance during development of the chick retina was studied by immunohistochemistry and Western blots. The patterns are mature one day before hatching. Each cell type acquires its characteristic calcium-binding protein several days after its differentiation has started, but in most cases before morphological maturation is complete. There is also an early phase of calbindin immunoreactivity in many immature amacrine cells, and of calretinin immunoreactivity in the presumptive photoreceptor layer, suggesting that these proteins may have distinct functions in differentiating cells.

Renal transplant pyelocaliectasis: role of duplex Doppler US in evaluation

To distinguish the obstructed from the nonobstructed dilated collecting system of transplanted kidneys without interventional diagnostic measures, the authors prospectively evaluated duplex Doppler analysis (determination of resistive index [RI]) in 35 renal transplant patients with pyelocaliectasis. Proof of the presence or absence of obstruction was obtained at interventional procedures in 18 patients and at clinical follow-up in 17. Thirteen kidneys were obstructed (mean RI, .81 +/- .06), while 22 had nonobstructive dilatation (mean RI, .66 +/- .07). The RI difference was statistically significant (P less than or equal to .01). Of 21 kidneys with a normal RI, only two had obstruction. In both of these, the obstruction was associated with a significant peritransplant collection of fluid due to a ureteral leak. In the seven obstructed transplanted kidneys with follow-up, the mean RI was .82 +/- .06 before nephrostomy and .67 +/- .05 after nephrostomy. Obstruction was a common cause of an elevated RI (greater than or equal to .75). Other causes of transplant dysfunction can be associated with an elevated RI and nonobstructed dilatation. More important, a normal RI should strongly argue against obstruction unless a ureteral leak is also present.

Magnetic resonance imaging of the normal craniovertebral junction

Sagittal magnetic resonance images of the normal craniovertebral junction in 25 patients were examined for visualization of bony, synovial, and ligamentous structures. The excellent delineation of soft tissue by magnetic resonance imaging enabled recognition of the joint space between the dens and anterior arch of C1 in 14 out of 25 patients. High-signal-intensity tissue was noted immediately superior to the dens in all patients; an anatomic specimen confirmed the fibrofatty nature of this tissue. The medullary space of the dens had lower signal intensity than did the marrow in the body of C2 in more than one half of the cases. Additional thin-section images suggested that this was a partial-volume artifact. Understanding of the normal appearances of structures in this region is necessary to assess correctly the presence or absence of disease.

Sarcoidosis: abdominal manifestations at CT

There are few data in the literature on the abdominal manifestations of sarcoidosis at computed tomography (CT). To determine whether differences in nodal distribution and appearance can be reliably used to distinguish between sarcoidosis and non-Hodgkin lymphoma (NHL), the authors retrospectively reviewed the abdominal and pelvic CT scans of 16 patients with biopsy-proved sarcoidosis and 20 patients with biopsy-proved NHL. Eleven of the 16 patients with sarcoidosis had abdominal and/or pelvic lymphadenopathy, which was common at all nodal sites except for the retrocrural and pelvic locations. There was a statistically significant lower frequency of retrocrual adenopathy in sarcoidosis than in NHL. Mean nodal size was significantly greater in NHL. Nodes tended to be confluent in NHL and discrete in sarcoidosis. Hepatomegaly was seen in six of the 16 patients (38%) with sarcoidosis and splenomegaly was present in nine of 15 (60%). CT depicted hepatic lesions in only three of eight patients (38%) with biopsy-proved hepatic involvement. Splenic lesions were seen at CT in five of the 15 patients (33%). The authors believe that the overlap in nodal appearance and distribution poses a limitation for use of these criteria in accurate disease characterization.

Intrarenal arterial Doppler sonography in patients with nonobstructive renal disease: correlation of resistive index with biopsy findings

The resistive index (RI), calculated from the duplex Doppler waveform, was compared with clinical and laboratory findings and the results of renal biopsy in 41 patients with nonobstructive (medical) renal disease. Kidneys with active disease in the tubulointerstitial compartment had a mean RI of 0.75 +/- 0.07. This was statistically significantly different (p less than .01) from the RI in kidneys with disease limited to the glomeruli (mean RI of 0.58 +/- 0.05). Acute tubular necrosis resulted in an elevated RI (mean RI = 0.78 +/- 0.03) as did vasculitis/vasculopathy (mean RI = 0.82 +/- 0.05). Patients with hypertension, proteinuria, or hematuria did not have kidneys with a significantly higher RI than did patients without these clinical factors. Kidneys found to be abnormally echogenic did not have an RI significantly different from kidneys of normal echogenicity. There was a weak correlation between creatinine level and RI value, reflected by a linear correlation coefficient of 0.34. In patients with normal renal RIs, the mean creatinine level was 1.7 +/- 1.7, whereas in those with abnormal RI values (greater than or equal to 0.70), the mean creatinine level was 3.7 +/- 3.6. We conclude that some forms of nonobstructive renal disease can produce changes in the Doppler waveform detectable by RI measurement. The production of Doppler waveform changes is strongly influenced by the site of the main disease within the kidneys. Active disease within the tubulointerstitial compartment (acute tubular necrosis, interstitial nephritis) or vasculitis/vasculopathy generally resulted in an elevated RI, whereas disease limited to the glomeruli, no matter how severe, did not significantly elevate the RI. Degree of renal dysfunction as indicated by serum creatinine level probably affects the Doppler waveform to some degree, but the relationship is weak.