Pediatric Abdominal Masses: Imaging Guidelines and Recommendations

Pediatric abdominal masses are commonly encountered in the pediatric population, with a broad differential diagnosis that encompasses benign and malignant entities. The primary role of abdominal imaging in the setting of a suspected pediatric abdominal mass is to establish its presence, as nonneoplastic entities can mimic an abdominal mass, and to identify characteristic imaging features that narrow the differential diagnosis. In the setting of a neoplasm, various imaging modalities play an important role to characterize the mass, stage extent of disease, and assist in presurgical planning. The purpose of this article is to discuss a practical imaging algorithm for suspected pediatric abdominal masses and to describe typical radiological findings of the commonly encountered abdominal masses in neonates and children with emphasis on imaging guidelines and recommendations.

Neonatal and Pediatric Bowel Obstruction: Imaging Guidelines and Recommendations

Pediatric bowel obstructions are one of the most common surgical emergencies in children, and imaging plays a vital role in the evaluation and diagnosis. An evidence-based and practical imaging approach to diagnosing and localizing pediatric bowel obstructions is essential for optimal pediatric patient care. This article discusses an up-to-date practical diagnostic imaging algorithm for pediatric bowel obstructions and presents the imaging spectrum of pediatric bowel obstructions and their underlying causes.

IgE blockade with omalizumab reduces pruritus related to immune checkpoint inhibitors and anti-HER2 therapies

Background:

Immunoglobulin E (IgE) blockade with omalizumab has demonstrated clinical benefit in pruritus-associated dermatoses (e.g. atopic dermatitis, bullous pemphigoid, urticaria). In oncology, pruritus-associated cutaneous adverse events (paCAEs) are frequent with immune checkpoint inhibitors (CPIs) and targeted anti-human epidermal growth factor receptor 2 (HER2) therapies. Thus, we sought to evaluate the efficacy and safety of IgE blockade with omalizumab in cancer patients with refractory paCAEs related to CPIs and anti-HER2 agents.

Patients and methods:

Patients included in this multicenter retrospective analysis received monthly subcutaneous injections of omalizumab for CPI or anti-HER2 therapy-related grade 2/3 pruritus that was refractory to topical corticosteroids plus at least one additional systemic intervention. To assess clinical response to omalizumab, we used the Common Terminology Criteria for Adverse Events version 5.0. The primary endpoint was defined as reduction in the severity of paCAEs to grade 1/0.

Results:

A total of 34 patients (50% female, median age 67.5 years) received omalizumab for cancer therapy-related paCAEs (71% CPIs; 29% anti-HER2). All had solid tumors (29% breast, 29% genitourinary, 15% lung, 26% other), and most (n = 18, 64%) presented with an urticarial phenotype. In total, 28 of 34 (82%) patients responded to omalizumab. The proportion of patients receiving oral corticosteroids as supportive treatment for management of paCAEs decreased with IgE blockade, from 50% to 9% (P < 0.001). Ten of 32 (31%) patients had interruption of oncologic therapy due to skin toxicity; four of six (67%) were successfully rechallenged following omalizumab. There were no reports of anaphylaxis or hypersensitivity reactions related to omalizumab.

Conclusions:

IgE blockade with omalizumab demonstrated clinical efficacy and was well tolerated in cancer patients with pruritus related to CPIs and anti-HER2 therapies.

Practical guide for pediatric pulmonologists on imaging management of pediatric patients with COVID-19

Understanding of coronavirus disease 2019 is rapidly evolving with new articles on the subject daily. This flood of articles can be overwhelming for busy practicing clinicians looking for key pieces of information that can be applied in daily practice. This review article synthesizes the reported imaging findings in pediatric Coronavirus disease 2019 (COVID-19) across the literature, offers imaging differential diagnostic considerations and useful radiographic features to help differentiate these entities from COVID-19, and provides recommendations for requesting imaging studies to evaluate suspected cases of pediatric COVID-19.

Reliability of Measuring Insertion Depth in Cochlear Implanted Infants and Children Using Cochlear View Radiography

OBJECTIVES

Cochlear implant depth of insertion affects audiologic outcomes and can be measured in adults using plain films obtained in the "cochlear view." The objective of this study was to assess interrater and intrarater reliability of measuring depth of insertion using cochlear view radiography.

STUDY DESIGN

Prospective, observational.

SETTING

Tertiary referral pediatric hospital.

SUBJECTS AND METHODS

Patients aged 11 months to 20 years (median, 4 years; interquartile range [IQR], 1-8 years) undergoing cochlear implantation at our institution were studied over 1 year. Children underwent cochlear view imaging on postoperative day 1. Films were deidentified and 1 image per ear was selected. Two cochlear implant surgeons and 2 radiologists evaluated each image and determined angular depth of insertion. Images were re-reviewed 6 weeks later by all raters. Inter- and intrarater reliability were calculated with intraclass correlation coefficients (ICCs).

RESULTS

Fifty-seven ears were imaged from 42 children. Forty-nine ears (86%) had successful cochlear view x-rays. Median angular depth of insertion was 381° (minimum, 272°; maximum, 450°; IQR, 360°-395°) during the first round of measurement. Measurements of the same images reviewed 6 weeks later showed median depth of insertion of 382° (minimum, 272°; maximum, 449°; IQR, 360°-397°). Interrater and intrarater reliability ICCs ranged between 0.81 and 0.96, indicating excellent reliability.

CONCLUSIONS

Postoperative cochlear view radiography is a reliable tool for measurement of cochlear implant depth of insertion in infants and children. Further studies are needed to determine reliability of intraoperatively obtained cochlear view radiographs in this population.

Imaging Assessment of Complications from Transplantation from Pediatric to Adult Patients: Part 1: Solid Organ Transplantation

End-stage organ failure is commonly treated with transplantation of the respective failing organ. Although outcomes have progressively improved over the decades, early and late complications do occur, and are often diagnosed by imaging. Given the increasing survival rates of transplant patients, the general radiologist may encounter these patients in the outpatient setting. Awareness of the normal radiologic findings after transplantation, and imaging findings of the more common complications, is therefore important. We review and illustrate the imaging assessment of complications from lung, liver, and renal transplantation, highlighting the key similarities and differences between pediatric and adult patients.

International Expert Consensus Statement on Chest Imaging in Pediatric COVID-19 Patient Management: Imaging Findings, Imaging Study Reporting, and Imaging Study Recommendations

Coronavirus disease 2019 (COVID-19) has quickly spread since it was first detected in December 2019 and has evolved into a global pandemic with over 1.7 million confirmed cases in over 200 countries around the world at the time this document is being prepared. Owing to the novel nature of the virus and the rapidly evolving understanding of the disease, there is a great deal of uncertainty surrounding the diagnosis and management of COVID-19 pneumonia in pediatric patients. Chest imaging plays an important role in the evaluation of pediatric patients with COVID-19; however, there is currently little information available describing imaging manifestations of COVID-19 in pediatric patients and even less information discussing the utilization of imaging studies in pediatric patients. To specifically address these concerns, a group of international experts in pediatric thoracic imaging from five continents convened to create a consensus statement describing the imaging manifestations of COVID-19 in the pediatric population, discussing the potential utility of structured reporting during the COVID-19 pandemic, and generating consensus recommendations for utilization of chest radiographs and CT in the evaluation of pediatric patients with COVID-19. The results were compiled into two structured reporting algorithms (one for chest radiographs and one for chest CT) and eight consensus recommendations for the utilization of chest imaging in pediatric COVID-19 infection. © RSNA, 2020.

Outpatient dermatology consultations for oncology patients with acute dermatologic adverse events impact anticancer therapy interruption: a retrospective study

BACKGROUND

Dermatologic adverse events (dAEs) of anticancer therapies may negatively impact dosing and quality of life. While therapy interruption patterns due to dAEs have been studied in hospitalized cancer patients, similar outcomes in outpatient oncodermatology are lacking.

OBJECTIVES

To analyse the therapy interruption patterns, clinico-histopathologic characteristics and management outcomes of outpatient dermatology consultations for acute dAEs attributed to the most frequently interrupted class of oncologic agents.

METHODS

We performed a retrospective cohort study of all cancer patients who received a same-day outpatient dermatology consultation for acute dAEs at our institution from 1 January to 30 June 2015. Relevant data were abstracted from electronic medical records, including demographics, oncologic history and explicit recommendations by both the referring clinician and consulting dermatologist on anticancer therapy interruption. Consultations with the most frequently interrupted class of oncologic treatment were characterized according to clinico-histopathologic features, dermatologic management and clinical outcomes.

RESULTS

There were 426 same-day outpatient dermatology consultations (median age 59, 60% female, 30% breast cancer), of which 295 (69%) had systemic anticancer therapy administered within 30 days prior. There was weak inter-rater agreement between referring clinicians and consulting dermatologists on interruption of anticancer treatment (n = 150, κ = 0.096; 95% CI -0.02 to 0.21). Seventy-three (25%) consultations involved interruption by the referring clinician, most commonly targeted therapy (24, 33%). Maculopapular rash was commonly observed in 23 consultations with 25 dAEs attributed to targeted agents (48%), and topical corticosteroids were most frequently utilized for management (22, 38%). The majority (83%) of consultations with targeted therapy-induced dAEs responded to dermatologic treatment and 84% resumed oncologic therapy, although three (19%) at a reduced dose. Rash recurred only in two instances (13%).

CONCLUSIONS

A high frequency of positive outcomes in the management of targeted therapy-induced dAEs by outpatient consulting dermatologists and low recurrence of skin toxicity suggests impactful reductions in interruption of anticancer therapy.

Pediatric Renal Neoplasms:: MR Imaging-Based Practical Diagnostic Approach

Pediatric renal tumors may be malignant or benign. Wilms tumor, the most common malignant pediatric renal tumor, arises sporadically or with various syndromes. Renal cell carcinoma typically presents in older children. Renal clear cell sarcoma and rhabdoid tumor are typically less common, more aggressive, and present in younger children. Benign renal tumors include mesoblastic nephroma, multilocular cystic renal tumor, angiomyolipoma, and metanephric adenoma. Lymphoma and leukemia may secondarily involve the kidney. Although there is overlap in the imaging appearance of several pediatric renal tumors, magnetic resonance characteristics and clinical data narrow the differential diagnosis and suggest a specific diagnosis. This article reviews current MR techniques, as well as the common MR imaging characteristics of malignant and benign pediatric renal neoplasms.

Practical administration of intravenous contrast media in children: screening, prophylaxis, administration and treatment of adverse reactions

Administration of intravenous contrast media to children is a routine practice at many clinical imaging centers, that can involve special considerations. In this paper, we provide practical information to facilitate optimal performance and oversight of this task. We provide targeted screening questions that can help to identify high-risk pediatric patients for both iodine-based and gadolinium-based intravenous contrast media administration. These include children at risk for allergic-like reactions, thyroid dysfunction, contrast-induced nephropathy, and nephrogenic systemic fibrosis. We make recommendations for addressing "yes" responses to screening questions using risk stratification schema that are specific to children. We also present criteria for selecting children for premedication prior to intravenous contrast administration, and suggest pediatric regimens. Additionally, we discuss practical nuances of intravenous contrast media administration to children and provide a quick-reference table of appropriate treatments with pediatric dosages for adverse contrast reactions.

Pediatric Mediastinal Masses:: Role of MR Imaging as a Problem-Solving Tool

Computed tomography (CT) is the imaging modality of choice for evaluating mediastinal masses detected by radiography or clinical presentation. However, CT results can often be indeterminate. Thoracic magnetic resonance (MR) imaging is a noninvasive way to characterize mediastinal lesions, site of origin, and involvement of adjacent structures by providing higher soft tissue contrast than CT, with superior tissue characterization and higher diagnostic specificity. Thoracic MR imaging of mediastinal masses can increase diagnostic certainty, reduce the number of surgical interventions, and improve clinical decision making. In this review article, current imaging techniques and clinical applications of MR imaging as a problem-solving tool for assessing mediastinal masses in pediatric patients are discussed.

Abstract P4-16-07: The CHANCE study: Mechanical skin changes among women with non-metastatic breast cancer receiving chemotherapy and endocrine therapy

Background: The persistent effects on skin hydration and elasticity resulting from cytotoxic and endocrine agents used in early stages of breast cancer are poorly understood. The objective of this preliminary analysis of the CHANCE study is to describe the pattern of persistent biomechanical skin changes in non-metastatic breast cancer patients treated with cytotoxic chemotherapies and/or endocrine therapies.

Methods: This is an ongoing single-center, prospective, longitudinal cohort study of non-metastatic breast cancer patients treated with cytotoxic chemotherapies and/or endocrine therapies. Objective skin hydration and elasticity measurements of the forearm were measured using Tewameter® (TM 300; Courage & Khazaka) and Cutometer® (MPA 580; Courage & Khazaka) devices under a controlled ambient environment at baseline and 6 months after chemotherapy completion, or one year after initiation of endocrine therapy.

Results: A total of 107 patients were assessed at baseline and follow-up for transepidermal water loss (TEWL) (median age 53, range 26-82) and 106 patients for skin elasticity (median age 53.5, range 26-82). Fifty-three healthy controls were evaluated at baseline with median age 47 (range, 22-73). The mean TEWL at baseline and follow-up among patients were 6.922 g/h/m2 and 8.521 g/h/m2, respectively (p&lt;.0001). Skin firmness (0.420 versus 0.421 mm, p=0.949) and elasticity (77.2% versus 77.4%, p=0.836) did not significantly change during follow-up. When comparing chemotherapy recipients with endocrine therapy recipients, chemotherapy patients had a mildly lower TEWL at follow-up (8.369 versus 8.928 g/h/m2, p=.247) but a greater net increase in TEWL (1.687 versus 1.359 g/h/m2, p=.5) compared to endocrine patients over the study period.

Conclusions: An increase in TEWL was observed in patients receiving cytotoxic and endocrine therapies, suggesting a deterioration of the protective skin barrier possibly attributed to these therapies. No significant changes in skin firmness or elasticity were found in this preliminary analysis. Further studies are needed to elucidate the pathophysiologic mechanisms involved in persistent skin changes after systemic breast cancer therapies.

Objective skin hydration and elasticity in patients receiving breast cancer therapy Control (n=53)Baseline (n=107)Follow-Up (n=107)p-value*TEWL (g/h/m2)9.4626.9228.521&lt;.0001Cutometer Baseline (n=106)Follow-Up (n=106) Immediate recovery, R0 (mm)0.4150.4200.4210.949Gross elasticity, R2 (%)79.3%77.2%77.4%0.836*p-value calculated from baseline and follow-up only

Citation Format: Lacouture ME, Phillips GS, Freites-Martinez A, Patil S, Samuels A, Shapiro J, Kukoyi O, Goldfarb S. The CHANCE study: Mechanical skin changes among women with non-metastatic breast cancer receiving chemotherapy and endocrine therapy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-16-07.

Intraoperative Doppler sonogram in pediatric liver transplants: a pictorial review of intraoperative and early postoperative complications

A spectrum of vascular complications can be seen in pediatric liver transplant patients, including occlusion and hemodynamically significant narrowing of the vessels that provide inflow to or outflow from the graft. Intraoperative Doppler ultrasound (US) has the potential benefit of identifying vascular complications in pediatric liver transplant patients prior to abdominal closure. Importantly, intraoperative Doppler US can be used as a problem-solving tool in situations such as position-dependent kinking of the portal or hepatic veins, or in suspected vasospasm of the hepatic artery. Furthermore, this technique can be used for real-time reassessment after surgical correction of vascular complications. This pictorial review of intraoperative Doppler US in pediatric liver transplant patients illustrates normal findings and common vascular complications, including examples after surgical correction, in the perioperative period.

Urethral Sphincter Mechanism Incompetence in 163 Neutered Female Dogs: Diagnosis, Treatment, and Relationship of Weight and Age at Neuter to Development of Disease

BACKGROUND

Urethral sphincter mechanism incompetence (USMI) is the most common cause of urinary incontinence in neutered bitches and is most common in dogs weighing >20 kg.

OBJECTIVES

To describe a population of neutered bitches with USMI and investigate their initial presentation, the relationship between weight and age at neuter, and treatment.

ANIMALS

One hundred and sixty-three female dogs with USMI (UI) diagnosed between January 2009 and December 2012, and 193 continent neutered control (C) bitches.

METHODS

Retrospective data were collected from neutered female dogs with USMI and healthy, continent neutered females presented between January 2009 and December 2012.

RESULTS

Urinary incontinent dogs weighed more than C dogs (P = .003), and there was no difference in age at neuter. The relationship between weight at diagnosis and age at neuter was found to impact the hazard of USMI. A decrease in the hazard of USMI was found in dogs weighing >25 kg for every month delay of neuter in the first year. The hazard did not change for dogs <15 kg. Median time from neuter to development of incontinence was 3.73 years. Phenylpropanolamine was prescribed in 75.5%, diethylstilbestrol in 21.5%, and both in 3.1% of dogs.

CONCLUSIONS AND CLINICAL IMPORTANCE

Neutering bitches expected to be >25 kg adult weight later in their first year may decrease the hazard of developing USMI, whereas age at neutering of bitches <25 kg may not impact continence. Heavier dogs have increased risk of USMI, and onset occurs within a few years of neuter.

A hairy situation: trichobezoar presenting with intussusception, and intestinal and biliary perforation in a child

Trichobezoars are an uncommon cause of acute abdominal pain. We present a case of a 12-year-old girl with a history of a trichobezoar who presented to the emergency department with acute abdominal pain. Abdominal sonography was performed which suggested portal venous gas and showed complex peritoneal fluid. Subsequent computed tomography demonstrated both gastric and small bowel bezoars, with a jejunojejunal intussusception, and confirmed portal venous gas and complex ascites. At the time of surgery, there was evidence of intestinal and biliary perforation. Our case illustrates a constellation of complications in association with a long-standing trichobezoar.

Bony cochlear nerve canal stenosis and speech discrimination in pediatric unilateral hearing loss

OBJECTIVES/HYPOTHESIS

To examine the relationship between bony cochlear nerve canal (BCNC) width, degree of hearing loss, and speech discrimination in children with unilateral sensorineural hearing loss (USNHL).

STUDY DESIGN

Retrospective chart review (case-control study).

METHODS

Audiometric database was cross-referenced with radiologic database at pediatric tertiary care facility to identify children with USNHL and temporal bone computed tomography. BCNC widths were measured independently by two radiologists blinded to affected ear. Regression analyses investigated associations among variables.

RESULTS

One hundred and sixty children with USNHL had temporal bone imaging. Mean BCNC width was significantly smaller in affected ears, P = 0.0001. Narrower width was associated with more severe hearing loss, P = 0.01. Among children who had narrower cochlear nerve canals in affected ears compared to unaffected ears, smaller width was associated with lower speech discrimination score, P = 0.03. Increasing asymmetry in BCNC width between affected and unaffected ears was associated with poorer discrimination scores, P = 0.02. Among ears with asymmetrically smaller cochlear nerve canals, a 1-mm reduction in cochlear canal width between the normal and affected ear was associated with 30.4% lower word recognition score percentage in the affected ear, P = < 0.001.

CONCLUSION

There is a significant association between BCNC stenosis and impaired speech discrimination, independent of degree of hearing loss. Further investigation is needed to determine whether BCNC stenosis is a poor prognostic factor for auditory rehabilitation.

Imaging in pediatric small bowel transplantation

Small bowel transplantation, alone or with other organs as multivisceral transplantation, is performed for patients with chronic intestinal failure. With advancing surgical techniques and improved post-surgical management, survival of these patients has increased tremendously in the last two decades. The radiologist has an important role in the preoperative and postoperative management of these patients. Knowledge of surgical techniques and post-surgical complications seen in the transplant recipient is necessary for adequate management of these patients.

Upper thoracic shape in children with pectus excavatum: impact on lung function

OBJECTIVE

Pectus excavatum (PE) can present with respiratory complaints in childhood. However severity of the PE, measured by the Pectus Severity Index (PSI), correlates only modestly with reduced vital capacity (VC). We hypothesized that another upper thoracic feature, a pectus gracilis (PG) or slender chest, co-exists with PE, and impacts lung function.

PATIENTS AND METHODS

We developed the Pectus Gracilis Index (PGI) based on the chest width to depth ratio at the gladiolar-manubrial sternal junction on computerized tomographic (CT) scans, and measured PGI among 316 control children 10-20 years old. PG was defined by PGI values >2 z-scores above the mean normal value. We determined the prevalence of PG in 97 children with PE and correlated PGI and PSI with VC among the 86 that performed spirometry.

RESULTS

The mean and upper limit of normal for PGI averaged 2.73 and 3.55, respectively for control children. The prevalences of a PG among controls and children with PEs were 3.2% and 59%, respectively (OR = 45, P < 0.00001). Among the children with PEs, the PGI, and PSI correlated with one another (r = 0.77, P < 0.001). Both PSI and PGI significantly correlated inversely with VC. (r = -0.34, P < 0.001 and r = -0.38, P < 0.001, respectively). Importantly, PGI correlated with VC after adjusting for PSI among children with PE. (r = 0.20, P < 0.03).

CONCLUSION

The upper thoracic feature of a PG is common among children with PE and contributes to reductions in VC. Assessment of the thorax, using the PGI, may improve the structure-function correlations previously described for children with PE.

Safety Essentials: Acute Reactions to Iodinated Contrast Media

The objectives of this article are to review the diagnosis and management of acute nonrenal reactions to iodinated contrast media. We will begin by discussing the types of contrast media and their correlative rates of reaction. The mechanism of contrast reactions, predisposing risk factors, and preventative measures will then be discussed. The remainder of the article will review the assessment of potential reactions, initial management, and treatment algorithms for specific reactions.

The utility of adding expiratory or decubitus chest radiographs to the radiographic evaluation of suspected pediatric airway foreign bodies

STUDY OBJECTIVE

This study aimed to compare test characteristics of standard (lateral and posteroanterior or anteroposterior) chest radiographs with and without special views (expiratory or bilateral decubitus) in the emergency department evaluation of children with suspected airway foreign bodies.

METHODS

From 1997 to 2008, 328 patients with a suspected airway foreign body had standard and special view chest radiographs: 192 with left and right decubitus views, 133 with expiratory views, and 3 with both. Patients were excluded for cardiorespiratory disease, chest wall deformity, visible airway foreign bodies on standard views, or spontaneously expelled airway foreign bodies. After blinded radiologist review, standard plus special view test characteristics were compared to standard views.

RESULTS

Nine upper airway and 70 tracheobronchial airway foreign bodies were identified by direct visualization or bronchoscopy, and the remainder were ruled out by bronchoscopy (50 patients) or clinically (199 patients). The sensitivity and specificity of the radiographs were, respectively, decubitus cohort, standard views, 56% and 79% and standard+decubitus views, 56% and 64%; expiratory radiograph cohort, standard views, 33% and 70% and standard+expiratory views, 62% and 72%. For standard plus decubitus views versus standard views alone, the relative sensitivity was 1.0 (0.56/0.56; 95% confidence interval [CI] 0.81 to 1.23) and the relative 1-specificity was 1.76 (0.36/0.21; 95% CI 1.3 to 2.37). For standard plus expiratory views versus standard views alone, the relative sensitivity was 1.87 (0.62/0.33; 95% CI 1.23 to 2.83) and the relative 1-specificity was 0.93 (0.28/0.3; 95% CI 0.6 to 1.44).

CONCLUSION

The addition of decubitus to standard views increases false positives without increasing true positives and lacks clinical benefit. The addition of expiratory to standard views increases true positives without increasing false positives, but test accuracy remains low and the clinical benefit is uncertain.

Usual and unusual causes of pediatric gastric outlet obstruction

Gastric outlet obstruction in children encompasses a spectrum of disorders that extends beyond hypertrophic pyloric stenosis. Each condition can result in the clinical syndrome of persistent nonbilious vomiting, which can progress to dehydration and electrolyte imbalances. This paper reviews the spectrum of both the common and uncommon entities that cause partial or complete gastric outlet obstruction and their imaging appearances. The correct diagnosis of those with gastric outlet obstruction can be achieved by combining clinical presentation with appropriate imaging, leading to optimal and timely patient management.

MRI of closed spinal dysraphisms

We present a pictorial review of MRI features of various closed spinal dysraphisms based on previously described clinicoradiological classification of spinal dysraphisms proposed. The defining imaging features of each dysraphism type are highlighted and a diagnostic algorithm for closed spinal dysraphisms is suggested.

Pediatric intestinal transplantation: normal radiographic appearance and complications

We present a pictorial essay on pediatric intestinal transplantation that describes the indications for pediatric intestinal transplantation, surgical technique, and the role of imaging in the pre-transplant work-up and detection of post-transplant complications. We illustrate the normal post-transplant imaging appearance and common complications, including rejection, infection, post-transplant lymphoproliferative disease (PTLD), mechanical dysfunction and vascular complications. We conclude with an imaging algorithm for suspected post-transplant complications based on clinical scenarios.

Labyrinthine dehiscence in a child

A 4-year-old boy presented with moderate to profound mixed hearing loss in the right ear and moderate to severe mixed hearing loss in the left ear, prompting a temporal bone CT scan. Images revealed partial dehiscence of the right posterior semicircular canal. Semicircular canal dehiscence and its associated clinical syndrome have been described in adults. We present this case as a unique finding in a child and discuss the possible clinical and research implications.

Polymerase chain reaction-based microsatellite polymorphism analysis of follicular and Hürthle cell neoplasms of the thyroid

Follicular and Hürthle cell carcinomas of the thyroid cannot be differentiated from adenomas by either preoperative fine needle aspiration or intraoperative frozen section examination, and yet there exist potentially significant differences in the recommended surgical management. We examined, by PCR-based microsatellite polymorphism analysis, DNA obtained from 83 thyroid neoplasms [22 follicular adenomas, 29 follicular carcinomas, 20 Hürthle cell adenomas (HA), and 12 Hürthle cell carcinomas (HC)] to determine whether a pattern of allelic alteration exists that could help distinguish benign from malignant lesions. Alterations were found in only 7.5% of informative PCR reactions from follicular neoplasms, whereas they were found in 23.3% of reactions from Hürthle cell neoplasms. Although there were no significant differences between follicular adenoma and follicular carcinoma, HC demonstrated a significantly greater percentage of allelic alteration than HA on chromosomal arms 1q (P < 0.001) and 2p (P < 0.05) by Fisher's exact test. The documentation of an alteration on either 1q or 2p was 100% sensitive and 65% specific in the detection of HC (P < 0.0005, by McNemar's test). In conclusion, PCR-based microsatellite polymorphism analysis may be a useful technique in distinguishing HC from HA. Potentially, the application of this technique to aspirated material may allow this distinction preoperatively and thus facilitate more optimal surgical management. Consistent regions of allelic alteration may also indicate the locations of critical genes, such as tumor suppressor genes or oncogenes, that are important in the progression from adenoma to carcinoma. Finally, this study demonstrates that Hürthle cell neoplasms, now considered variants of follicular neoplasms, differ significantly from follicular neoplasms on a molecular level.

Polymerase chain reaction-based microsatellite analysis of fine-needle aspirations from Hürthle cell neoplasms

Fine-needle aspiration (FNA) of the thyroid is the sine qua non in the preoperative evaluation of thyroid nodules. Despite this, cytological examination of FNA cannot differentiate malignant from benign Hürthle cell neoplasms. We have previously shown that Hürthle cell carcinomas harbor more genetic alterations on chromosomal arms 1q and 2p than Hürthle cell adenomas, and that all Hürthle cell neoplasms have a significantly higher frequency of alterations on chromosomal arm 1p compared with normal thyroid. To determine if these genetic alterations could be detected in FNA samples, we examined DNA from FNAs that were available from eight Hürthle cell neoplasms. Polymerase chain reaction (PCR) amplification of DNA demonstrated either direct correlation with alterations seen in the tumor samples or in some instances, additional chromosomal alterations. We conclude that PCR-based microsatellite DNA analysis of preoperative FNA samples from Hürthle cell neoplasms can potentially distinguish Hürthle cell carcinomas from adenomas and that with further validation and perfection, this technique may allow more optimal surgical management of patients with these lesions.

Splenic abscess: another look at an old disease

OBJECTIVE

To study the changes in the incidence, causes, bacteriologic profile, and management of a splenic abscess.

DESIGN

Retrospective case study.

SETTING

Tertiary, university referral center.

PATIENTS

Thirty-nine patients with a splenic abscess.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Demographics, signs and symptoms, causes, risk factors, diagnostic methods, bacteriologic profile, treatment, and outcome.

RESULTS

Patients presented at a mean age of 43 years (range, 2-83 years), after a mean symptomatic period of 16 days, with fever (69%), abdominal pain (56%), nausea and vomiting (38%), and splenomegaly (31%). The majority of abscesses represented metastatic infection (n=19), and 11 were secondary to immunosuppression. Twelve patients had human immunodeficiency virus disease and 9 used intravenous drugs. In patients who underwent computed tomography, all had abnormal scans (n=33), with a well-defined abscess(es) in 28. Nine abscesses were polymicrobial; monomicrobial isolates included gram-positive organisms (23%), gram-negative organisms (31%), fungi (23%), and mycobacteria (23%). Patients presenting before 1989 (1981-1988) (n=15) and those presenting after 1989 (1989-1996) (n=24) differed in risk factors (intravenous drug abuse, 0% vs 47% [P=.02]; hematologic malignancy, 43% vs 9% [P=.04]) and gram-positive isolates (18% vs 64%; P=.06). Patients underwent splenectomy (n=18), open drainage (n=4), medical therapy (n=10), or percutaneous drainage (n=5) with respective survival rates of 94%, 50%, 70%, and 100%.

CONCLUSIONS

In 1996, splenic abscesses are increasingly common. Intravenous drug abuse and human immunodeficiency virus disease are significant risk factors, and the diagnosis should be considered in a patient with fever and abdominal pain who uses intravenous drugs. Antimicrobial agents should be broad since 36% of abscesses were polymicrobial, and should include coverage of gram-positive organisms.

A comparison of the reliability of repeat cervical smears and colposcopy in patients with abnormal cervical cytology

BACKGROUND

To determine the reliability of repeat cervical smears (Papanicolaou smears) in patients who have had an abnormal initial smear, prospective data were collected on patients being followed up for a previously abnormal cervical smear.

METHODS

All 428 patients who were referred for colposcopy because of abnormal cervical smears underwent simultaneous cervical smears and coloposcopy with directed biopsy. Patients with colposcopic evidence of invasive carcinoma or a history of prior colposcopy were excluded. Cervical smear results were compared with the histologic findings on colposcopically directed biopsy. The ability of cervical smears to identify cervical intraepithelial neoplasia (CIN) and high-grade lesions (CIN 2 and 3) were also calculated for the repeat cervical smear.

RESULTS

The sensitivity of repeat Papanicolau screening for CIN was 48%. When differentiating high-grade lesions from low-grade and benign biopsies, the sensitivity of the repeat cervical smear was only 25%. Of 110 patients with biopsy-proven high-grade lesions, 68% had low-grade initial cervical smears and 73% had low-grade or benign repeat cervical smear cytology.

CONCLUSIONS

This study demonstrates that repeated Pap smears often fail to identify high-grade lesions and that the sensitivity of a repeat cervical smear is very low in patients with low-grade abnormalities found on routine screening examinations. Using follow-up cervical smears to monitor patients who have low-grade squamous intraepithelial lesions (LGSIL) carries unacceptable risks. A more reliable diagnostic test such as colposcopy is indicated.