Radiographic analysis of deep cervical abscesses

CT differentiation of abscess and non-infected fluid in the postoperative neck

BACKGROUND

Differentiation of postoperative neck abscess from non-infected fluid is important because the treatment is different.

PURPOSE

To determine specific CT findings that might help to differentiate abscesses from non-infected fluid collections in the postoperative neck.

MATERIAL AND METHODS

We retrospectively reviewed CT scans of 50 patients (43 men and 7 women; mean age, 62.5 ± 8.9 years) who had postoperative fluid collections in the neck (26 abscesses and 24 non-infected fluid collections). Diagnosis of an abscess was determined by a positive bacteria culture from the fluid collection. Diagnoses were correlated with the following CT findings: anatomic spaces involved, the maximum transverse diameter, margin, attenuation, rim enhancement, gas bubbles, and manifestations of soft tissue adjacent to a fluid collection.

RESULTS

Rim enhancement pattern and soft tissue manifestations showed significant differences between abscess and non-infected fluid. The reliable CT findings for abscess were: (i) rim enhancement > 50% of the circumference, 54% sensitive, 71% specific, and 62% accurate; and (ii) severe soft tissue manifestations, 39% sensitive, 92% specific, and 64% accurate. There were no significant differences in the anatomic spaces involved, the maximum transverse diameter, margin, attenuation, and gas bubbles between abscess and non-infected fluid.

CONCLUSION

CT findings that may help differentiate postoperative neck abscess from non-infected fluid were rim enhancement > 50% of the circumference and severe soft tissue manifestations.

Parapharyngeal abscess in children: five year retrospective study

Lateropharyngeal and retropharyngeal abscesses are potentially life threatening infections in children

Aim

To review the etiologic, clinical, and imaging signs of lateropharyngeal and retropharyngeal abscesses in children as well as treatment-outcomes and complications using a surgical trans-oral approach.

Method

Retrospective analysis of 11 children, hospitalized in the last 5 years, with a diagnosis of lateropharyngeal (n = 8) and retropharyngeal (n = 3) abscesses, ages ranging from 0 to 12 years old. Charts and CT scans were reviewed.

Result

The average age of presentation was 3.3 years. Neck stiffness (64%) and odynophagia (55%) were the most common symptoms. Fever (64%), stiff neck (64%), bulging of the oropharyngeal wall (55%), mass in the neck (55%) and lymphadenopathy (36%) were the most prevalent physical findings. All these patients were submitted to surgical drainage using a trans-oral approach in the first 48 hours after admission. About 82% of the patients showed improvement after 48 hours, and 100% after 72 hours, without any complications.

Conclusion

Based on the good clinical outcomes and low incidence of complications, the present study suggests that antibiotic therapy complemented with a timely surgical treatment, is a valid treatment option in refractory parapharyngeal abscesses.

Infecciones cervicales profundas: etiología, bacteriología y terapéutica

Deep neck infections are dangerous for its potential ease to fascial spread, sepsis, and upper airway obstruction. This article reviews 77 cases of deep cervical infection, focus on etiological, clinical and therapeutic aspects. The most frequent location was the submaxillary area (29%), followed by the parapharyngeal space (28%), floor of the mouth (27%) and retropharyngeal (14%) spaces. Etiology was dental in 32%; pharyngoamigdalar infection in 27%; foreign bodies in 13%. In 22% the cause is unknown. Two or more bacteria were isolated in 72%, with Streptococcus B haemolytic being the most frequent germ. All patients were treated with intravenous broad-spectrum antibiotics. Surgical drainage was needed in 54%, and tracheotomy in 18%. Four patients developed mediastinitis, and one died as a consequence of it. The incidence of deep neck infections has decreased after the itroduction of antibiotics but they still may be lethal especially when life-threatening complications occur. Early recognition and management are necessary.

History of possible foreign body ingestion in children: don??t forget the rarities

Foreign body ingestion in children is a common presenting complaint to the emergency department. Although the majority of ingested foreign bodies pass through the gastrointestinal tract unaided, some children will require either non-surgical or surgical intervention. Retained oesophageal foreign bodies may cause a multitude of problems, including mucosal ulceration, inflammation or infection, and more seriously paraoesophageal or retropharyngeal abscess formation, mediastinitis, empyema, oesophageal perforation and aorta-oesophageal fistula formation. We present a case of a 12-month-old child in whom delayed diagnosis of glass ingestion resulted in the development of a retropharyngeal abscess, oesophageal perforation and mediastinitis. Such complications following foreign body ingestion in children are rare but potentially fatal. A high index of suspicion must be maintained in young children presenting with a possible history of foreign body ingestion as a delayed diagnosis may lead to significant morbidity and mortality. We review the literature surrounding paediatric retropharyngeal abscesses and mediastinitis.

Accuracy of computerized tomography in deep neck infections in the pediatric population

OBJECTIVES

Computerized tomography (CT) is used widely to diagnose deep neck infections (DNIs), and, generally, the decision of surgical intervention is based on findings of a CT study. This study examines the accuracy of CT in differentiating abscess versus cellulitis in DNIs (lateral pharyngeal and retropharyngeal).

STUDY DESIGN

This is a retrospective chart review study with re-evaluation of the CT scans by a blinded observer.

METHODS

A retrospective review of medical records of 80 patients with DNIs who were evaluated with a CT study was performed. CT scans of these patients were reviewed by a radiologist who was blinded to the clinical and surgical findings and to the original CT study report. To diagnose the infection and differentiate abscess from cellulitis, our radiologist scored the CT scans regarding the following variables: low-density core, rim enhancement, soft-tissue swelling, obliterated fat planes, and mass effect. Radiologic diagnosis was compared with operative findings (whether pus found at surgery or not) in all cases treated surgically. Accuracy, sensitivity, specificity, and positive and negative predictive values of CT study were calculated.

RESULTS

Thirty-nine (49%) patients were treated medically with intravenous (IV) antibiotics alone, and 41 (%51) patients were treated both surgically and medically. The overall accuracy of CT in DNI was 63%. The sensitivity, specificity, and positive and negative predictive values were 68%, 56%, 71%, and 53%, respectively.

CONCLUSION

CT study has important limitations in differentiating abscess versus cellulitis in DNIs. Clinical findings as well as CT diagnosis should guide the decision of surgery.

CT and MR imaging evaluation of neck infections with clinical correlations

Infection of the neck is a common clinical problem in all age groups, especially children and young adults. The clinical symptoms and signs are often suggestive of the diagnosis. Imaging studies including CT and MR imaging are frequently required to confirm the diagnosis but more importantly to localize the infectious process and search for and delineate an abscess cavity. Ultrasound has also been used in the evaluation of superficial neck infections, especially to determine fluid accumulation. Conventional films consisting of an anteroposterior and lateral view were the examination before the introduction of CT in 1972. Conventional films can still be used for a preliminary survey, especially of the retropharyngeal space when there is a question of a retropharyngeal phlegmon or abscess.

Comparison of the sensitivity of lateral neck radiographs and computed tomography scanning in pediatric deep-neck infections

OBJECTIVE

To compare the sensitivity of lateral neck films and computed tomography (CT) scanning with contrast in evaluating children with a high index of suspicion for a deep-neck infection, either retropharyngeal, parapharyngeal, or combined based in clinical presentation.

STUDY DESIGN

A retrospective chart review of children presenting to the Children's Hospital of Buffalo, New York, with the diagnosis of a deep-neck infection between January 1991 and November 1997 was conducted. In total, 57 children were included in the study, ranging in age from 12 to 119 months (1-10 y).

METHODS

Charts were reviewed for presenting signs, symptoms, and laboratory values and included only those children with the presence of fever, limited neck range of motion, a lateral neck mass, dysphagia, and a leukocyte count greater than 15,000 cells/mm3. Results of lateral neck radiographs and CT scanning with contrast were evaluated and compared when available.

RESULTS

Lateral neck radiographs were found to have a sensitivity of 83% for determining the presence of a pediatric deep-neck infection, whereas CT scanning with contrast had a sensitivity of 100.

CONCLUSION

Lateral neck radiographs were found to offer no benefit in the workup of children strongly suspected of having a deep-neck infection based on clinical presentation. Despite the higher cost, CT scanning with contrast is the recommended radiologic test in such cases. This single study allows the determination of size, type, and location of the infectious process and is invaluable in treatment planning for pediatric patients with infection in deep-neck spaces.

Deep neck infections in children: a new approach to diagnosis and treatment

Forty-seven children presented with the diagnosis of a deep neck infection--either cellulitis or abscess--between January 1991 and July 1996. Forty-four (94%) had contrast-enhanced computed tomography (CT) imaging consistent with this diagnosis. Three patients with no CT scan had confirmation of an abscess at surgical drainage. Parenteral antibiotics alone were effective in the treatment of 24 of 47 infections (51%): seven parapharyngeal, one retropharyngeal, and 16 combined. By CT scan these infections represented cellulitis in 17 of 24 (71%), an abscess in three of 24 (13%), and incomplete abscess in four of 24 (17%). The average duration of hospitalization for this group was 4.8 days, with symptomatic improvement usually seen within 24 hours. Surgical drainage was performed on 23 of 47 infections (49%): three parapharyngeal, 17 combined, and three of unknown specific location. In 22 of these 23 children (96%), transoral drainage of the abscess was used as the primary surgical approach. In 21 of these 22 (95%) there was complete resolution without complications or recurrence; one abscess required a subsequent external approach. CT scanning with contrast revealed that all deep neck infections were located medial (usually anteromedial) to the great vessels. Abscesses with volumes estimated to be greater than 2000 mm3 were more likely to undergo surgery, but these differences were not statistically significant. The use of contrast-enhanced CT scanning provides information regarding abscess size, location, and relative position of the great vessels for safe and successful transoral drainage. Thus we recommend CT-assisted transoral drainage for combined retropharyngeal/parapharyngeal abscesses and selected isolated parapharyngeal abscesses that do not respond to parenteral antibiotics.

Pediatric deep space neck infections: the Medical College of Wisconsin experience

A retrospective review was performed on 39 patients with deep space neck infection admitted to the Children's Hospital of Wisconsin over a nine year period. The signs and symptoms as well as issues of diagnosis and treatment were reviewed with attention to the use of computed tomography (CT) scans. Beta hemolytic streptococcus was the most commonly cultured organism followed by alpha hemolytic streptococcus. Sixteen patients underwent CT scans. Twelve were diagnosed with an abscess by CT scan. An abscess was confirmed in ten patients. Necrotic lymph nodes mimicked abscesses on CT scans and resulted in negative surgical findings. Airway obstruction occurred in 30% of the children in the study. Children under the age of 36 months had a significantly higher rate of airway obstruction upon presentation compared to older children (P < 0.05). There should be a high index of suspicion of upper airway compromise in children under the age of 36 months with a deep neck infection.

Comparison of computed tomography and surgical findings in deep neck infections

Computed tomography is routinely used in the evaluation of patients suspected to have deep neck infections. This 10-year retrospective study compares preoperative computed tomography scan reports with intraoperative findings in 38 patients who underwent surgical exploration of the parapharyngeal or retropharyngeal space within 48 hours of their radiographic assessment. Overall, intraoperative findings confirmed computed tomography scan interpretation in 76.3% of the patients. The false-positive rate was 13.2%, and the false-negative rate was 10.5%. The sensitivity of computed tomography scan for detection of parapharyngeal space or retropharyngeal space abscess was 87.9%. This study's documentation of false-positive computed tomography scans in the evaluation of deep neck infections emphasizes the importance of correlating radiologic interpretation with clinical examination before surgical intervention.