Ultrasound of pancreatic transplant complications: a primer for radiologists.

Pancreatic transplantation is an established treatment for patients with type 1 diabetes patients and select type 2 diabetes patients, with excellent survival rates as graft health is evaluated through regular imaging and early detection of complications. Amongst the various imaging methods that may aid in diagnosis of pancreatic transplant complications, ultrasound is a widely available, quick, portable, and cost-effective technique, often used as the sole method to assess for pancreatic transplant complications. When assessing a patient with a pancreatic transplant, the radiologist should be methodical in assessing the vasculature, the pancreatic parenchyma, and the peripancreatic regions. Complications can be categorised based on time from transplant and type of complications, and include vascular, parenchymal, and enteric/anastomotic complications. Doppler has a major role in the diagnosis of vascular complications including arterial and venous thrombosis, arterial stenosis, pseudoaneurysms, and haematomas. Pancreatic complications include rejections and pancreatitis, and are often diagnosed through a combination of clinical, laboratory, and imaging findings, such as pancreatic heterogeneity or the presence of pancreatic pseudocysts. Enteric/anastomotic complications include leaks and bowel obstructions, and may require cross-sectional imaging in addition to ultrasound. This review covers the most common and high-impact vascular, parenchymal, and enteric/anastomotic complications that should be considered in every radiologist's search pattern when assessing a pancreatic graft, as well as their respective postoperative timeframes.

Nonoperative management of blunt splenic injury in adults 55 years and older: a twenty-year experience.

The nonoperative management of splenic injury secondary to blunt trauma in older patients remains controversial. We have reviewed our experience from January 1978 to December 1997 with selective nonoperative management of blunt splenic injury in adults 55 years and older. Criteria for nonoperative management included hemodynamic stability with any transient hypotension corrected using less than 2,000 cm3 crystalloid infusion, a negative abdominal physical examination ruling out associated injuries, and a blood transfusion requirement of no more than 2 units attributable to the splenic injury. During the study period, 18 patients over age 55 with radiographic confirmation of a splenic injury met the above criteria for nonoperative management. Their mean age was 72 years (range 56-86), and 13 of the 18 were female (72%). The mean Injury Severity Score was 15 (range 4-29), with the mechanism of injury equally divided between automobile crashes (9) and falls (9). During a similar time period, 15 patients 55 years or older with splenic injury composed an operative group; these patients did not differ with respect to age (mean 68 years), sex (60% female), or mechanism of injury. CT scans of 8 patients managed nonoperatively were available and graded using the American Association for the Surgery of Trauma classification, with a mean score of 2.3 (range 2-3). Eight of the 18 nonsurgical patients received blood transfusions. None of the 18 patients who met the criteria for nonoperative management "failed" the protocol, and none were taken to the operating room for abdominal exploration. Two patients (11%) died of associated thoracic injuries after lengthy hospital stays, one at 10 days and one at 24 days. We conclude from our data that nonoperative management of blunt splenic injury in patients age 55 years and older is indicated provided they are hemodynamically stable, do not require significant blood transfusion, and have no other associated abdominal injuries.

Nonoperative management of adult blunt splenic trauma: a 15-year experience.

From January 1989 to December 1993, 40 consecutive adult patients with ruptured spleen from blunt trauma were examined. Fourteen patients (35%) were taken to the operating room initially because of hemodynamic instability and generalized peritoneal signs. Twenty-six patients (65%) were hemodynamically stabilized at admission and treated by nonoperative management, which included strict bed rest, intensive care unit monitoring, frequent physical examinations, and serial hematocrits. Four patients failed nonsurgical management and required a splenectomy, three because of clinical deterioration within 1 to 3 days of admission; the fourth patient had recurrent bleeding 7 days after injury. The patients in the operative group had a greater severity of injury with a mean injury severity score of 26.6, four deaths, and mean transfusion requirements of 3.7 to 4.0 units of blood, compared to a mean injury severity score of 14.6, one late death from cardiac causes, and average blood requirement of 0.4 to 0.7 units. Splenic injury grading averaged 3.2 in the surgical group (grade 1, one patient; grade 2, four patients; grade 3, eight patients; grade 4, no patients; and grade 5, one patient) and differed significantly from that of the nonoperative group (mean = 2.4; grade 1, 12 patients; grade 2, seven patients; grade 3, six patients; grade 4, two patients; and grade 5, no patients). Recent ultrasound analysis of select grades I to IV has shown excellent resolution or repair of these injuries. This report extends our series from 1978 to 1993 and includes 144 adult patients sustaining blunt splenic ruptures. Seventy-nine (55%) of these patients were treated nonsurgically. Seven patients (of 80) failed nonoperative management and required interval laparotomy, representing a 91 per cent success rate. Follow-up on more than 90 per cent of the patients has shown no sequelae from their splenic injuries. We conclude that adult patients with splenic injuries from blunt trauma who are hemodynamically stable and are without abdominal findings requiring celiotomy can be safely managed by a nonoperative approach.

MR cholangiopancreatography (MRCP).

Magnetic resonance cholangiopancreatography (MRCP) is an evolving new technique for noninvasive imaging of diseases of the biliary tree and pancreatic duct. The advantage of this method is that one can obtain maximum intensity projection (MIP) images of the pancreatico-biliary system similar to those obtained with endoscopic retrograde cholangiopancreatography (ERCP) without the need of administration of intravenous or oral contrast. Heavily T2-weighted sequences are used that render the bile and the intraductal pancreatic fluid bright against a dark background.

The use of ultrasonography in the localization of the lumpectomy cavity for interstitial brachytherapy of the breast.

PURPOSE: To determine the value of breast ultrasonography (US) in defining the lumpectomy cavity for patients treated with interstitial brachytherapy. METHODS AND MATERIALS: In March 1993, a protocol of low dose rate (LDR) interstitial brachytherapy as the sole radiation modality in selected patients with early breast cancer was initiated at William Beaumont Hospital. To date, 60 patients have been entered in this protocol, and 38 have undergone US assisted placement of interstitial brachytherapy needles. The lumpectomy cavity was outlined in all dimensions and corresponding skin marks were placed for reference at time of implantation. These US dimensions were compared to the physician's clinical estimate of the location of the lumpectomy cavity, the patient's presurgical mammogram, and the position of the surgical scar. In the intraoperative setting, the dimensions of the lumpectomy cavity were also obtained and the placement of the deep plane of interstitial needles was verified by US. RESULTS: The full extent of the lumpectomy cavity was underestimated by clinical examination (physical exam, operative report, mammographic information and location of the surgical scar) in 33 of 38 patients (87%). The depth to the chest wall was also incorrectly estimated in 34 (90%) patients when compared to US examination. Intraoperatively, US was performed in nine patients and was useful in verifying the accurate placement of the deepest plane of interstitial brachytherapy needles. In 7 of 9 patients (75%), clinical placement of needles did not ensure adequate coverage of the posterior extent of the lumpectomy cavity as visualized by intraoperative US. CONCLUSIONS: In breast cancer patients considered for interstitial brachytherapy, US appears to be a more accurate means of identifying the full extent of the lumpectomy cavity when compared to clinical estimates. In addition, US allows real-time verification of needle placement in the intraoperative setting.

Low-dose-rate brachytherapy as the sole radiation modality in the management of patients with early-stage breast cancer treated with breast-conserving therapy: preliminary results of a pilot trial.

PURPOSE: We present the preliminary findings of our in-house protocol treating the tumor bed alone after lumpectomy with low-dose-rate (LDR) interstitial brachytherapy in selected patients with early-stage breast cancer treated with breast-conserving therapy (BCT). METHODS AND MATERIALS: Since March 1, 1993, 60 women with early-stage breast cancer were entered into a protocol of tumor bed irradiation only using an interstitial LDR implant with iodine-125. Patients were eligible if the tumor was < or = 3 cm, margins were > or = 2 mm, there was no extensive intraductal component, the axilla was surgically staged, and a postoperative mammogram was performed. Implants were placed using a standardized template either at the time of reexcision or shortly after lumpectomy. A total of 50 Gy was delivered at 0.52 Gy/h over a period of 96 h to the lumpectomy bed plus a 2-cm margin. Perioperative complications, cosmetic outcome, and local control were assessed. RESULTS: The median follow-up for all patients is 20 months. Three patients experienced minimal perioperative pain that required temporary nonnarcotic analgesics. There have been four postoperative infections which resolved with oral antibiotics. No significant skin reactions related to the implant were noted and no patient experienced impaired would healing. Early cosmetic results reveal minimal changes consisting of transient hyperpigmentation of the skin at the puncture sites and temporary induration in the tumor bed. Good to excellent cosmetic results were noted in all 19 patients followed up a minimum of 24 months posttherapy. To date, 51 women have obtained 6-12-month follow-up mammograms and no recurrences have been noted. All patients currently have no physical signs of recurrence, and no patient has failed regionally or distantly. CONCLUSION: Treatment of the tumor bed alone with LDR interstitial brachytherapy appears to be well tolerated, and early results are promising. Long-term follow-up of these patients is necessary to establish the equivalence of this treatment approach compared to standard BCT, however.

Hypogenetic lung syndrome: functional and anatomic evaluation with magnetic resonance imaging and magnetic resonance angiography.

A case of hypogenetic lung syndrome is described in which anatomic and functional information was obtained with use of ECG-triggered turbo (fast) spin-echo, cine, velocity-encoded cine, and contrast-enhanced magnetic resonance angiography (MRA) sequences. To the best of our knowledge, a complete functional and anatomic study of hypogenetic lung syndrome with MRI has not been previously reported.

Imaging of abdominal hernias.

Abdominal hernias are a common clinical problem. The main types of abdominal hernias are external or abdominal wall hernias, which involve protrusion of abdominal contents through a defect in the abdominal wall; internal hernias, which involve protrusion of viscera through the peritoneum or mesentery and into a compartment in the abdominal cavity; and diaphragmatic hernias, which involve protrusion of abdominal contents into the chest. Clinical diagnosis of abdominal hernias can be difficult. However, plain radiography, radiography performed after administration of barium, and computed tomography allow evaluation of suspected abdominal hernias and detection of those that are clinically occult. The anatomic location of the hernia, the contents, and complications such as incarceration, bowel obstruction, volvulus, and strangulation can be demonstrated with radiologic examination. Occasionally, complications such as neoplasms or inflammatory conditions can be identified in the hernial contents. With abdominal imaging modalities, a variety of abdominal hernias can be confidently diagnosed.

Hepatic focal nodular hyperplasia: CT and sonographic spectrum.

Fifteen patients with pathologically proven focal nodular hyperplasia (FNH) of the liver had abdominal computed tomography (CT) (15) and ultrasound (11). In seven patients, the lesions were incidentally found during gallbladder or renal examination, whereas the other eight had a primary neoplasm and the liver was studied for possible metastasis. In 11 unenhanced CT scans, the ratio of isodense to hypodense lesions was 8 to 3. In 15 contrast-enhanced CT scans, seven were isodense, six were hypodense, and in two, the lesion enhanced (hyperdense). In seven patients a hypodense lesion on unenhanced CT became isodense with contrast injection. Delayed images in three showed the lesions appearing as hypodense in two and displaying a rim of enhancement in one. In one case, unenhanced CT was normal and only enhanced CT showed an area of homogeneous increased density. Ultrasound was done in 11 patients, the lesion was hypoechoic to the liver in five, echogenic in four, and isoechoic in two. Findings of central scar were seen on CT and ultrasound in three cases. Pathologic diagnosis was available in all cases, seven by needle aspiration and eight by surgical resection. In our experience, FNH has many CT and sonographic features that can mimic hemangioma or metastasis. While the presence of a central scar increases the specificity, in a cancer patient, the findings should be interpreted with caution and needle aspiration should be obtained.

Congenital malformations of the cervicothoracic lymphatic system: embryology and pathogenesis.

Familiarity with the embryology of the lymphatic system is helpful in understanding the pathogenesis and radiologic appearance of lymphangiomas of the cervicothoracic region. By considering anatomic location and radiologic appearance, one can predict the type of lymphangioma present, the primordial lymph sac from which the malformation arose, and when it formed in embryonic life. Cystic hygromas are composed of large, dilated lymphatic spaces. They form when a primordial lymph sac fails to reestablish communication with the central venous system from which it arose. These lesions may also result from an aberrant bud arising from a primordial lymph sac. Cavernous and capillary lymphangiomas are composed of smaller lymphatic channels. They form from abnormally sequestered buds of the developing lymphatic mesenchyme responsible for the fine meshwork of terminal branches in the periphery of the embryo. Their growth may be inhibited by the relatively tougher tissues in the periphery (eg, skin and muscle) compared with the relatively loose fatty connective tissue in which cystic hygromas form. Not only can all types of lymphangioma occur in one lesion, but lymphatic and vascular malformations may also coexist.

Color Doppler ultrasound of the genitourinary tract.

This paper discusses the role of color Doppler ultrasonography (CDU) as it applies to the genitourinary tract. CDU is beneficial in evaluating both the native and allograft kidney in the diagnosis of renal arterial and venous stenosis, arteriovenous fistulas, pseudoaneurysms, arterial and venous thrombosis, and in the characterization and staging of renal masses. CDU has redefined the role of ultrasonography in the evaluation of the scrotum as it relates to testicular torsion, inflammatory disorders and varicoceles. Early results of CDU in prostate carcinoma and benign prostate hypertrophy have shown limited success. Identifying and assessing the neurovascular bundle may have an impact on the staging of prostate carcinoma. It is hoped that the future addition of ultrasound contrast agents will further establish the role of color Doppler in the diagnosis of a variety of genitourinary diseases and disorders.

Endorectal sonography in the evaluation of rectal and perirectal disease.

Endorectal sonography initially was developed for evaluation of the prostate and now has been adapted for evaluation of rectal and perirectal disease. We used endorectal sonography to evaluate a spectrum of diseases, including primary and recurrent rectal carcinoma, metastases, villous adenoma, leiomyosarcoma, endometriosis, sacrococcygeal teratoma, chordoma, retroperitoneal cystic hamartoma, pelvic lipomatosis, diverticulitis, and perirectal abscess. The technique has been useful in localization of perirectal abscesses and in sonographically guided biopsy of perirectal masses. Knowledge of normal sonographic anatomy of the rectum is essential in the evaluation of rectal and perirectal disease. In this essay, we describe the technique of endorectal sonography and illustrate the sonographic findings in a variety of diseases.

Sonography of large scrotal infections.

We have described 14 cases of large scrotal infections with diffuse involvement of testis and epididymis, thick septations within the cavity, and associated thickening of the scrotal wall and tunica albuginea. The combination of these findings should help distinguish this process from a diffuse neoplastic involvement of the testis where the scrotal wall is almost always of normal thickness. The presence of patchy inhomogenous testicular echo pattern should alert the sonologist to the presence of diffuse suppurative epididymo-orchitis, which may result in necrosis with subsequent orchiectomy in such patients.