Appearance of oxidized cellulose (Surgicel) on postoperative CT scans: similarity to postoperative abscess

Does the use of Surgicel affect postsurgical radiological follow-up of kidney tumors?

Remaining Surgicel in the body can be mistaken for complications such as hematoma, abscess, or tumor recurrence in paraclinical examinations after surgery. We have presented the case of kidney cancer who underwent radical nephrectomy. In radiological follow-ups, hematoma was reported in the surgery site. The typical appearance of Surgicel on a postoperative CT scan is characterized by air trapped bubbles. Surgicel exhibits a short relaxation time on T2-weighted images. It is important to differentiate the remaining Surgicel from cases such as hematoma, abscess and tumor recurrence. T2MRI images will be most accurate in the correct diagnosis of Surgicel.

Oxidised cellulose-based reaction mimicking a suspicious ovarian mass: a case report and a systematic review

Oxidised regenerated cellulose was introduced 60 years ago to control diffuse bleeding from large surfaces. Although considered safe and effective, foreign body reactions can mimic suspicious masses in several organs. We describe the third case, reported in PubMed, of an oxidised regenerated cellulose-based granuloma mimicking a suspicious ovarian tumour on MRI. During surgery, the diagnosis was suspected by granulomatous tissue and confirmed by pathology. The follow-up after the excision was uneventful. Although a rare complication, physicians should be aware of this presentation and of the recommendation to remove excess Surgicel after the bleeding has stopped.

A contemporary systematic review of the complications associated with SURGICEL

BACKGROUND

This review aims to summarize the findings from recent literature (2010-2022) reporting on complications that resulted from the surgical use of SURGICEL for intraoperative hemostasis.

METHODS

A literature search was conducted using the MEDLINE (OVID), Embase, and Cochrane Central Register of Controlled Trials - CENTRAL (OVID) databases. The studies were sorted into case reports and other study types for data extraction. Covidence was used for data extraction and statistics were descriptive.

RESULTS

Of the total 560 articles screened, 73 papers were selected for a full-text review and 70 studies were included in this review. A total of 7,242 participants were included in the studies (case studies n = 93, others n = 7149). 67/70 of the included studies reported complications when SURGICEL was used intraoperatively. Reported complications included: SURGICEL induced masses (granulomas, abscesses, hematomas, cysts) (n = 25), hemorrhagic complications (n = 12), masses misdiagnosed as tumors, cardiovascular, nervous system, and hepatobiliary complications, pain, and infections. Other complications included: fistulas, erectile dysfunction, chorioamnionitis, swelling, urinary leak, renal failure, and anaphylaxis.

CONCLUSIONS

Publications reporting on complications associated with the use of SURGICEL intraoperatively have continued to emerge. Future studies should compare how the types and rates of complications compare between SURGICEL and alternative hemostatic agents.

US Evaluation of Topical Hemostatic Agents in Post-Thyroidectomy

BACKGROUND

the aim of this study was to describe the ultrasound appearance of topical hemostatics after thyroidectomy.

METHODS

we enrolled 84 patients who were undergoing thyroid surgery and were treated with two types of topical hemostats, 49 with an absorbable hemostat of oxidized regenerated cellulose (Oxitamp^®) and 35 with a fibrin glue-based hemostat (Tisseel^®). All patients were examined using B-mode ultrasound.

RESULTS

In 39 patients of the first group (approximately 80%), a hemostatic residue was detected and in some cases confused with a native gland residue, or with cancer recurrence in oncological patients. No residue was detected in patients in the second group. The main ultrasound characteristics of the tampon were analyzed and arranged according to predefined patterns, and suggestions to recognize it and avoid wrong diagnoses were provided. A part of the group of patients with tampon residue was re-evaluated after 6-12 months, ensuring that the swab remained for months after the maximum resorption time declared by the manufacturer.

CONCLUSIONS

with equal hemostatic effectiveness, the fibrin glue pad is more favorable in the ultrasound follow-up because it creates reduced surgical outcomes. It is also important to know and recognize the ultrasound characteristics of oxidized cellulose-based hemostats in order to reduce the number of diagnostic errors and inappropriate diagnostic investigations.

Rubber Dam Clamp May Cause Cortical Necrosis: A Case Report

INTRODUCTION

Tooth isolation methods utilized during endodontic procedures are necessary to create an aseptic field and protect the patient's alimentary tract from irrigate and instrument insult. This case details changes that can occur in mandibular cortical bone architecture following the use of a stainless steel rubber dam clamp during an endodontic procedure.

CASE REPORT

A 22 year-old, otherwise healthy woman underwent non-surgical root canal therapy on tooth #31 (mandibular right second molar, symptomatic irreversible pulpitis and peri-apical periodontitis.) Cone beam computed tomographic (CBCT) imaging obtained between treatments revealed irregular erosive and lytic changes of the crestal-lingual cortical bone resulting in sequestrum formation with infection and exfoliation. Continued monitoring and six-month post-treatment CBCT revealed complete resolution without further intervention.

DISCUSSION

When a stainless steel rubber dam clamp is placed onto gingiva overlying mandibular alveolar bone, bony changes can occur presenting with radiographic signs of cortical erosion and may result in necrosis of the cortical bone with sequestrum formation. Knowledge of this potential outcome improves our understanding of the normal course progression after dental procedures utilizing a rubber dam clamp for tooth isolation.

FDG PET/CT Features of Polysaccharide-Based Hemostatic Agent: Chronic Inflammatory Changes Can Mimic Metastatic Lesions

PURPOSE

To prevent hemorrhagic complications, hemostatic agents (HAs) have been widely used in recent years. The use of HAs can lead to false-positive results on postoperative imaging. There exists only 1 study in the literature evaluating these applications during surgical procedures. Therefore, we aimed to evaluate the postoperative imaging features of polysaccharide-based HAs in thoracic surgery patients who have had 18F-FDG PET/CT scans.

PATIENTS AND METHODS

Two hundred nine consecutive patients who underwent thoracic surgery were enrolled in this study. A topical polysaccharide-based HA was applied to the surgical bed for all of the patients. The patients diagnosed with cancer were followed up with subsequent thoracic CT scans, and 42 of these patients were also imaged with 18F-FDG PET/CT, which then comprised the main study group. Due to suspicion of metastasis, 19/42 patients were reoperated or rebiopsied. The latest histopathological findings were accepted as criterion standard, and previous FDG PET/CT images were retrospectively reevaluated.

RESULTS

Polysaccharide-based HAs that appear as amorphous basophilic material were identified in histopathological samples of 11/19 patients. Lymphocytes, plasma cells, and histiocytes, which formed foreign body reaction and/or foreign body granuloma, indicating the presence of chronic inflammation, were seen in all of the samples. 18F-FDG PET/CT showed increased FDG uptake in all of these lesions.

CONCLUSIONS

Despite the inconsistency of the literature, polysaccharide-based HAs can be demonstrated in human surgical specimens as amorphous basophilic materials even after a long time from the initial surgical procedure. These agents almost always cause chronic inflammatory changes. In addition, these agents may mimic "false-positive" findings on postoperative FDG PET/CT scans.

Liver trauma in the intensive care unit

PURPOSE OF REVIEW

To review the surgical and critical care management of liver trauma; one of the most common abdominal injuries sustained due to its size and location.

RECENT FINDINGS

Hepatic injuries range from negligible to life threatening: in the acute phase, the most common cause of morbidity and mortality is hemorrhage; however, severe traumatic hepatic injuries can also lead to biochemical abnormalities, altered coagulation, and ultimately liver failure. This brief review will review the classification of traumatic liver injuries by mechanism, grade, and severity. Most Grades I-III injuries can be managed nonoperatively, whereas the majority of Grades IV-VI injuries require operative management. Therapeutic strategies for traumatic liver injury including nonoperative, operative, radiologic will be described. The primary goal of liver trauma management in the acute setting is hemorrhage control, then the management of secondary factors such as bile leaks. The rapid restoration of homeostasis may prevent further damage to the liver and allow for deferred nonoperative management, which has been shown to be associated with good clinical outcomes.

SUMMARY

A multidisciplinary approach to the care of these patients at an experienced liver surgery center is warranted.

Oxidized Regenerated Cellulose Mimicking a Retained Laparotomy Sponge

Oxidized regenerated cellulose (ORC) is an absorbable hemostat commonly used during gynecologic surgery. We present a case in which ORC was used in a patient undergoing posterior pelvic exenteration with ureteroneocystostomy for excision of a malignant pelvic mass. At the conclusion of these procedures, the laparotomy pad count was reported as incomplete likely due to the large number of laparotomy pads used and changes in nursing staff. Abdominal radiographs were obtained to verify no pads were retained in the abdominal cavity. These identified a poorly defined radiolucency deep in the patient's pelvis, requiring the surgical incision be reopened. Upon reexploration, no evidence of a retained surgical sponge could be identified. However, ORC was identified at the site of the radiolucency in question. Radiographs of this material, once removed, confirmed its radiolucent appearance. This experience clearly demonstrates that oxidized regenerated cellulose can mimic a retained surgical sponge on intraoperative radiographs. Dissemination of this knowledge will hopefully help to avoid radiographic misidentification of ORC in the perioperative window and minimizing the risk of unnecessary surgical interventions in the future.

Multimodality imaging of Surgicel®, an important mimic of post-operative complication in the thorax

Absorbable hemostatic agents such as Surgicel are hemostatic materials composed of an oxidized cellulose polymer used to control post-surgical bleeding and cause coagulation. This material is sometimes purposefully left in situ where it slowly degrades over time and can produce an imaging appearance that mimics serious post-operative complications such as gangrenous infections and anastomotic leaks as well as potentially mimicking disease recurrence in later stages. In this article, we review the multimodality imaging appearance of this material in situ longitudinally in the range of post-operative settings, in order to promote awareness of this entity when interpreting post-operative imaging. We present this as a pictorial review focusing primarily but not exclusively on the chest noting that the thoracic imaging appearance of Surgicel^® is less well reported in the published literature. An understanding of this entity may help to minimize erroneous diagnosis of a postoperative complication leading to unnecessary interventions.

Topical Coagulant Agents

Topical hemostatic agents have continued to develop as knowledge of coagulation physiology and pathophysiology has evolved. The addition of knowledge of hemostatic agents to a surgeon's armamentarium helps to push the boundaries of life-saving care. As the understanding of the complex physiology of coagulation and hemorrhage improves, so will the potential for developing hemostatic agents that are safe, affordable, and readily available. This article discusses topical coagulant agents and hemostatic materials currently available in the surgery. The relevant agents/materials, their characteristics, different utility in surgical hemostasis, and their relevant benefits and drawbacks are reviewed.

A randomized controlled trial to compare the efficacy of regenerated and non-regenerated oxidized cellulose gauze for the secondary treatment of local bleeding in patients undergoing hepatic resection

Purpose

Oxidized cellulose is available in many forms, but manufactured using either a regenerated or non-regenerated process. In this study, we evaluated the effects of 2 different hemostatic agents for the treatment of local bleeding in patients undergoing hepatic resection.

Methods

This was a monocentric, parallel-group, randomized, and controlled clinical trial to compare oxidized regenerated cellulose gauze (ORCG) with oxidized non-regenerated cellulose gauze (ONRCG) in patients undergoing hepatectomy. The primary endpoint was the time to hemostasis at the target bleeding site. The secondary endpoints were the postoperative drainage volume on the first 2 days after surgery and the hospital stay.

Results

There was no significant difference between the ORCG and ONRCG groups in time to hemostasis from column analysis (238.8 ± 121.6 seconds vs. 193.7 ± 85.3 seconds, P = 0.068), and there were no differences in the rates of hemostatic success between the 2 groups at 120 seconds (18.4% vs. 24.3%; odds ratio [OR], 0.703; 95% confidence interval [CI], 0.231–2.136) and 300 seconds (71.1% vs. 89.2%; OR, 0.298; 95% CI, 0.085–1.041). However, the ONRCG group was superior to the ORCG group in hemostasis according to the survival analysis (log-rank test, P = 0.044). Moreover, there were also no significant differences between the 2 groups in postoperative drainage volume on the first 2 days (P = 0.436, P = 0.381) and hospital stay (P = 0.537, P = 0.200).

Conclusion

ONRCG was not inferior to ORCG as a hemostatic agent in patients undergoing liver resection.

Surgicel mimicking recurrent pelvic neuroblastoma in a 3-year-old boy

INTRODUCTION

Surgicel is a hemostatic agent that consists of oxidized regenerated cellulose and used in surgical procedures as an aid to bleeding control. It is left in the operation site for hemostasis, could cause an operation by mimicking the recurrence of tumor, as in our patient.

PATIENTS AND METHODS

A 3-year-old boy was operated by us at the age of 40 days and 2.5 years, respectively, due to pelvic neuroblastoma. He was re-operated for mimicking recurrence or residue tumor secondary to the prior placement of Surgicel within the peritoneal cavity.

RESULTS

Re-laparotomy was performed and the mass approximately 2.8 × 2×1 cm in size in front of the right ureter and iliac vessels and behind the bladder was removed by blunt and sharp dissection without damaging these organs. While gelatinous content was evacuated from this mass, there was no apparent tumor appearance. Pathology report was reported as fibrotic tissue characterized by foreign body and foreign body giant cells. The postoperative period was uneventful and he was discharged on the 2nd postoperative day.

CONCLUSIONS

In the light of our case, the use of hemostatic agents should be kept to a minimum and should not be left in the body unless it is difficult. Thus, unnecessary examination or recurrent surgery can be avoided.

Article Commentary: Hemostats, Sealants, and Adhesives: A Practical Guide for the Surgeon

Hemostats, sealants, and adhesives are useful adjuncts to modern surgical procedures. To maximize their benefit, a surgeon needs to understand the safety, efficacy, usability, and cost of these agents. To be truly added to a surgeon's own toolbox, the operator must also have knowledge of when and how to best use these materials. This commentary is designed to succinctly facilitate this understanding and knowledge. A nomenclature and classification system based on group, category, and class has been created to help with this process and is provided here. By using this system, materials consisting of similar design and for common indications can be compared. For example, in this system, the three functional groups are hemostats, sealants, and adhesives. The hemostats may be divided into four categories: mechanical, active, flowable, and fibrin sealant. These hemostat categories are further subdivided into generic classes based on the composition of the approved materials. Similarly, categories and classes are provided for sealants and adhesives. In this commentary, the salient points with respect to the characteristics of these agents are presented. A discussion of when these agents can be used in specific indications and how they may be applied to achieve the best results is also provided.

Surgicel on the post-operative CT: an old trap for radiologists

Percutaneous drainage of post-operative collections following abdominopelvic surgery has become standard practice and is a routine procedure in many interventional radiology (IR) departments. Such collections are commonly diagnosed on CT studies where the presence of Surgicel ^® can mimic an abscess and lead to unnecessary procedures. We present a case where a duodenal perforation was masked by post-operative Surgicel in the gallbladder fossa, which in turn was mistaken for an infected biloma and referred for percutaneous interventional radiology drainage. Careful imaging review, correlation with operative notes and good diagnostic radiological technique led to a correct diagnosis and avoided unnecessary intervention.

Mimics of Complications in the Postsurgical Aorta at CT

Various surgical techniques of the aorta result in expected imaging appearances on CT images that resemble complications such as pseudoaneurysm, perigraft abscess, and dissection. Awareness of these techniques, understanding the clinical situation in which they are performed, and familiarity with the typical appearances and locations of these mimics are essential for accurate interpretation. CT imaging techniques such as electrocardiographic gating and inclusion of a precontrast series can help distinguish an expected postsurgical finding from a complication. Information in the medical record, particularly the operative note, can clarify challenging cases with unusual imaging features. This review article provides examples of expected postsurgical findings at CT mimicking complications. © RSNA, 2019.

The safety and benefit of using oxidized regenerated cellulose to position free flap pedicle in head and neck reconstruction

BACKGROUND

Oxidized regenerated cellulose (ORC; Surgicel®; Ethicon, Neuchâtel, Switzerland) is an absorbable hemostatic agent used for hemostasis in operation, although some surgeons use it to position free flap pedicles. The increasing risk of vessel compromise is a huge concern. However, no scientific data to date demonstrate the safety and benefit of using ORC in microvascular surgery. In the present study, we compared the outcome of microvascular head and neck reconstruction with and without pedicle placement using ORC.

MATERIALS AND METHODS

From January 2015 to December 2017, we reviewed patients undergoing microvascular surgery with free fibular osteocutaneous flap in our hospital. The patients were divided into the ORC group and non-ORC group and their baseline characteristics and outcomes were compared.

RESULTS

In total, there were 27 patients in the ORC group and 67 in the non-ORC group. The non-ORC group had significantly higher cigarette consumption (70.4% vs. 89.6%; p = .022). The outcome of the ORC group was better regarding arterial thrombosis (0% vs. 3%), flap failure (0% vs. 4.5%), hematoma (7.4% vs. 10.4%), and wound complications (25.9% vs. 44.8%). The ORC group had a worse result than the non-ORC group for vein thrombosis (7.4% vs. 4.5%) and duration of hospitalization (24.111 days vs. 23.627 days). However, none of above results was significant.

CONCLUSIONS

Though this study was underpowered to detect the differences, the results showed a trend toward better outcomes of flaps and wounds in the ORC group. It seems that using ORC in this field is safe and beneficial.

Comparison of the sonographic findings in laparoscopic cholecystostomy with and without hemostatic agent on 45-day follow-up of patients attending hospital

Introduction:

Cholelithiasis is one of the most prevalent pathological conditions, and elective laparoscopic cholecystostomy with and without hemostatic agent (HA) is the therapeutic approach to its treatment. This research study aimed to compare the sonographic findings of patients who underwent cholecystostomy with and without HA use.

Materials and Methods:

This cross-sectional, descriptive-analysis study was conducted by available nonprobability sampling technique, and according to Cochran Formula, 144 patients, who underwent laparoscopic cholecystostomy, were recruited and divided into two groups including a group of 85 patients with HA use and a group of 59 patients without HA use. Patients in each group had sonography on discharge date and 15, 30, and 45 days after the surgery. Data were collected and entered in SPSS-24 software; meanwhile, descriptive statistics was used to analyze Chi-square test, Fisher's exact test, and Friedman and Wilcoxon nonparametric test.

Findings:

The results of the study showed that the presence of echogenic mass with reverberation artifact (abscess mucosa) on 15- and 30-day follow-up sonography of patients, who underwent laparoscopic cholecystostomy, were significantly higher in patients with HA than in the group without HA (P < 0.05), and on 45-day follow-up sonography, there was no significant correlation regarding the presence of echogenic mass with reverberation artifact (abscess mucosa) and fluid in the two groups (P > 0.05). Besides, HA density significantly decreases in individuals over time (P < 0.05); however, there was no significant differences between HA reduction rate and gender (P > 0.05).

Conclusion:

These findings might be the indication of HA agents’ effect on surgical operations and their resemblance to abscess. Due to the possibility of temporary immune responses to HA, as an external object, it is necessary, in vital pathologies, to pay close attention to what differentiates the normal imaging appearance in follow-up sonography.

Surgicel® packing remnants mimicking mediastinitis after adult cardiac surgery

Surgicel® is one of the most commonly used bioabsorbable topical haemostatic agents. Some articles have reported that Surgicel® remnants might be misdiagnosed as an abscess. However, the number of reports in the cardiothoracic surgical field is limited. Herein, we report a 65-year-old woman who was suspected of having mediastinitis on computed tomography after redo-Bentall operation. Reoperation revealed that internal accumulation of Surgicel® remnants mimicked mediastinitis. It is important to share the use and location of Surgicel® with radiologists. If mediastinitis cannot be ruled out, the next step of reoperation or magnetic resonance imaging should be promptly taken.

Magnetic resonance imaging characteristics and changes in hemostatic agents after partial nephrectomy

PURPOSE

To evaluate the characteristics of images generated by magnetic resonance imaging (MRI) and changes in the mass-like lesion (MLL) during the follow-up of patients who underwent partial nephrectomy (PN) with the intra-operative use of hemostatic agents (HAs).

METHODS

The records of patients who had undergone PN in our clinic due to renal mass between January 2013 and August 2018 were retrospectively reviewed. Our study included 47 patients who were administered one or more HAs during the PN and who received diffusion and dynamic MRI at the post-operative 2nd/4th Queryand 12th month.

RESULTS

MLL is defined as T2 heterogeneous, intermediate-signal intensity bolster-related mass with a pseudocapsule in the renal parenchymal defect. When we looked at the morphological changes of MLL, the mean largest axial dimensions of masses were 27.3 (range 12.2-44.7) mm in the first follow-up period (2nd/4th months) and 21.2 (range 11-44.7) mm in the 12th month follow-up period. The average change in size of MLL was - 0.66 mm/month. We did not see any significant relationship between observation of MLL in the post-operative follow-up MRI images and the use of HAs such as Surgicel^®, Spongostan^®, and autologous fatty tissue as well as the amount of the agents used in PN operations (p = 0.405, p = 0.159, respectively).

CONCLUSIONS

The distinction of MLL causing bolster-related mass and granulomatosis tissue from relapse/recurrence can be made based on the change in mass size observed in the MR images and image characteristics.

Hemostatic Agents and Tissue Sealants: Potential Mimics of Abdominal Abnormalities

OBJECTIVE

Topical tissue sealants and hemostatic agents, seen on postoperative imaging in a variety of intraabdominal and pelvic locations, have the potential to be mistaken for abdominal abnormalities, especially if the radiologist is not aware of the patient's surgical history. The normal appearance of these agents may mimic abscesses, tumors, enlarged lymph nodes, or retained foreign bodies. Therefore, it is important to be familiar with their typical imaging appearances and to review the surgical records when needed to avoid misdiagnoses. The purpose of this article is to increase the radiologist's familiarity with various types of topical tissue sealants and hemostatic agents used during surgical and percutaneous procedures in the abdomen and pelvis along with their radiologic appearances.

CONCLUSION

Various types of hemostatic agents are now commonly used during surgery and percutaneous procedures in the abdomen and pelvis, and it is important to recognize the various appearances of these agents. Although there are suggestive features outlined in this article, the most important factor for the radiologist is to be aware of the patient's history and the possibility that a hemostatic agent may be present. On postoperative imaging, hemostatic agents may mimic abscesses, tumors, enlarged lymph nodes, or retained foreign bodies, and accurate diagnosis can save a patient unnecessary treatment. It is therefore crucial to incorporate knowledge of the patient's surgical history with recognition of the typical imaging appearances of hemostatic agents and other pseudolesions to avoid misdiagnoses.

Practical Suggestions for Prevention of Complications Arising from Oxidized Cellulose Retention: A Case Report and Review of the Literature

BACKGROUND Bleeding is a major intraoperative complication during surgical procedures. When conventional methods such as ligature and diathermocoagulation are ineffective for bleeding management, hemostatic agents should be used. Oxidized cellulose is one of the major hemostatic agents used worldwide. Oxidized cellulose is often left in situ after hemostasis because of its high level of reabsorption that lasts up to 8 weeks. However, 38 cases of retaining-associated complications are reported in the literature. CASE REPORT A 51-year-old male patient presented in our emergency department with acute abdominal pain, nausea, and vomiting. The patient had been admitted in our department for laparoscopic cholecystectomy for acute cholecystitis 25 months previously. Abdominal ultrasound and CT scan showed the presence of a cystic circular mass, with homogeneous fluid content, close to the surgical clips of the previous surgery, resembling a "neogallbladder". Laparoscopic abdominal exploration and drainage were performed. Histological examination reported protein-based amorphous material with rare lymphocytes and macrophages. Culturing was negative for bacterial growth. The patient was discharged uneventfully on the 4 th postoperative day. The primary surgical report was evaluated with evidence of application of Gelita-Cel ® Standard for hemostatic purposes. Results of 12-month follow-up were normal. CONCLUSIONS Herein, we report the first case of a complication associated with the use of Gelita-Cel ® Standard. We reviewed the literature to better define the purpose and limits of oxidized cellulose use as a hemostatic agent. Despite the fundamental role of oxidized cellulose as a hemostatic agent, we provide some practical suggestions to prevent the reported severe complications and surgical overtreatments.

Use of oxidized regenerated cellulose to achieve hemostasis during laparoscopic cholecystectomy: a retrospective cohort analysis

OBJECTIVE

Laparoscopic cholecystectomy is the first-choice treatment for symptomatic cholelithiasis. Though generally safe, this procedure is not without complications, with bleeding the most frequent cause of conversion to open cholecystectomy. Oxidized regenerated cellulose (ORC) added to conventional hemostatic strategies, is widely used to control bleeding during surgery despite limited evidence supporting its use. This retrospective study analyzed patients undergoing laparoscopic cholecystectomy in an Italian center over a 16-month period, between October 2014 and February 2016, who experienced uncontrollable bleeding despite the use of conventional hemostatic strategies, requiring the addition of ORC gauze (Emosist®).

RESULTS

Of the 530 patients who underwent laparoscopic cholecystectomy, 24 (4.5%) had uncontrollable bleeding from the liver bed. Of these, 62.5% had acute cholecystitis and 33.3% chronic cholecystitis; 1 patient was diagnosed with gallbladder carcinoma, postoperatively. Most patients had comorbidities, 16.7% had liver cirrhosis, and 37.5% used oral anticoagulants. The application of ORC rapidly controlled bleeding in all patients. Patients were discharged after a mean duration of 2.2 days. ORC was easy to use and well tolerated. Bleeding complications remain a relevant issue in laparoscopic cholecystectomy. ORC was able to promptly stop bleeding not adequately controlled by conventional methods and appears, therefore, to be a useful hemostat.

Effect of fibrin vs cellulose based haemostatic agents with traditional haemostatic procedures in thyroid surgery

Objective:

To compare the efficacy of fibrin-based hemostat and cellulose-based hemostat with traditional procedures in patients undergoing thyroid surgery.

Methods:

Between January 2012 and December 2016, 255 patients were scheduled to undergo total thyroidectomy at Surgical Clinic Nis. The patients were randomized to: Group-I use of classic surgical procedures to achieve hemostasis, Group-II use Surgicel and Group-III use Beriplas

Results:

A statistically significant reduction of surgical time was found for Group-I compared with Group-II and III (p≤0.01 for both groups). Statistically significant reduction of intraoperative blood loss was found for Group-I compared with Group-II from 102.3mL vs. 86.1mL (p≤0.01) as well as compared to Group-III (mean 77.4mL, p≤0.01). Removal of the wound drain occurred sooner in the Group-II and III compared with Group-I (mean 37.1h vs. 40.1h, p≤0.05; mean 31.2h vs. 40.1h, p≤0.01). There were no significant differences in terms of postoperative morbidity among the groups.

Conclusions:

Fibrin based haemostat seems to be an effective hemostatic agent for patients undergoing thyroid surgery. We suggest that, where appropriate, this fibrin-based haemostat should be used as a first line hemostatic agent in thyroidectomy in combination with conventional surgical means of hemostasis.

Subhepatic mass occurrence after using oxidized and regenerated cellulose polymer in laparoscopic cholecystectomy: a case series

BACKGROUND

Oxidized regenerated cellulose (ORC) is a bioabsorbable surgical hemostatic. We present the first prospective case series of circumscribed mass occurrence after using ORC in laparoscopic cholecystectomy.

METHODS

Tabotamp (Ethicon, Inc., Somerville, NJ) in the form of tightly woven knitted patches was used to achieve hemostasis in 83 patients submitted to LC.

RESULTS

A subhepatic mass was detected in five patients and radiologic characteristics were described. Abdominal contrast enhanced CT showed a heterogeneous soft-tissue mass. NMR was performed in one patient and showed a T2-weighted hyperintense mass.

CONCLUSION

ORC retention after surgery is not uncommon at long-term follow-up. The radiologic characteristics of a suspected ORC retention mass can differentiate it from a neoplastic lesion, so that surgery can be avoided.

Computed Tomographic Characterization of Traumastem-A New Oxidized Cellulose Hemostatic Agent

Oxidized regenerated cellulose (ORC) is a commonly used surgical hemostatic agent. When retained at the surgical site, it is frequently misdiagnosed on postoperative computed tomography (CT) images as an abscess or a recurrent tumor. Oxidized nonregenerated cellulose (ONC) is a new, more effective version of ORC. It is more effective because of its unorganized fiber structure and greater material density, which may also alter its appearance on CT images relative to ORC. This image report compares the CT characteristics of ONC and ORC. A rabbit's bilateral femoral arteries were punctured to model peripheral vascular surgery. ORC was used to treat 1 of the femoral artery punctures and ONC to treat the contralateral puncture. Noncontrast CT imaging was performed immediately following surgery (day 0) and on postoperative day 14. On day 0, both ORC and ONC were isoattenuating relative to muscle and hyperattenuating to fat, although ONC appears more homogenous. On day 14, neither ORC nor ONC was clearly identifiable. Thus, postoperative retention of ONC can obscure immediate postoperative CT interpretation and, similar to ORC, lead to an erroneous diagnosis of an abscess. By day 14, ONC retention may not obscure CT interpretation. In noncontrast CT imaging, ONC appears more homogeneous than ORC, but is otherwise indistinguishable. The greater homogeneity of ONC may be caused by the unorganized fiber structure or greater material density. Intraoperative use of ONC should be clinically investigated before radiographically diagnosing a postoperative abscess or recurrent tumor.

Computed Tomography Imaging Features and Changes in Hemostatic Agents After Laparoscopic Partial Nephrectomy

PURPOSE

Urologists and radiologists should be aware of the CT scan appearance of laparoscopic partial nephrectomy (LPN) with the various hemostatic agents since they may confound the interpretation of these radiographic findings. We report the various postoperative CT scan appearance and changes after LPN.

MATERIALS AND METHODS

We reviewed CT scans retrospectively (within 3 months) of 86 patients who underwent LPN using various hemostatic agents between March 2008 and July 2014. We analyzed the CT findings after LPN, including postoperative changes, tumor recurrence, and complications. We also discuss changes in abnormal features, such as mass-like lesions and gas formation, on follow-up CT scans.

RESULTS

To categorize the postoperative changes, we classified them according to their specific CT findings: (1) a combination of perinephric stranding and postsurgical fluid collection (n = 46), (2) mass-like lesions (n = 35), (3) a parenchymal defect (n = 2), (4) local recurrence at the surgical site (n = 1), (5) a large hematoma as a complication after LPN (n = 2), (6) gas pockets, which may be a response to postsurgical fluid collection around soft tissue (n = 35), (7) fat at the excision site (n = 2; Fig. 7 ), and (8) contrast extravasation in the delayed phase (n = 1). Mass-like lesions were visible in 35 cases. The average change in size of bolster masses was -1.19 mm/month. However, the overall change in enhancement of mass-like lesions was not significant over time. Foci of gas were noted in 16 patients at the resection site in the first follow-up period (<3 months), as late as 40 days after the procedure.

CONCLUSIONS

Knowledge of CT imaging features and changes in hemostatic agents following LPN is important in interpreting postoperative CT scans, as postoperative changes can be confused with tumor recurrence and can mimic abscesses.

Surgicel® granuloma mimicking ovarian cancer: A case report

Surgicel^® is an absorbable sterile mesh composed of oxidized cellulose that is used to control intraoperative capillary or venous bleeding, due to its capacity to bind hemoglobin, thus allowing the formation of an artificial clot. In the present study, a large granuloma mimicking ovarian cancer, which developed following placement of a Surgicel^® sponge during a combined pubovaginal sling procedure and cystocele repair, is reported. The aim of the present case report is to emphasize the fact that hemostatic measures should be removed following their use, and to alert surgeons to the risk of using and leaving in situ oxidized cellulose. Furthermore, accurate evaluation of the surgical history of the patient should always be performed prior to attempting surgery.

Multimodality Imaging of Liver Infections: Differential Diagnosis and Potential Pitfalls

Imaging plays an important role in the diagnosis, characterization, and management of infectious liver disease. In clinical practice, the main contributions of imaging are in detecting early disease, excluding other entities with a similar presentation, establishing a definitive diagnosis when classic findings are present, and guiding appropriate antimicrobial, interventional, or surgical treatment. The most common imaging features of bacterial, viral, parasitic, and fungal hepatic infections are described, and key imaging and clinical manifestations are reviewed that may be useful to narrow the differential diagnosis and avoid pitfalls in image interpretation. Ultrasonography (US), computed tomography (CT), and magnetic resonance imaging allow accurate detection of most hepatic infections and, in some circumstances, may provide specific signs to identify the underlying pathogen and exclude other entities with similar imaging features. In bacterial and parasitic infections, specific imaging features may be enough to exclude a neoplasm and, occasionally, to identify the underlying infectious agent. US and CT are important means to guide percutaneous aspiration or drainage when needed. In viral infections, imaging is critical to exclude entities that may manifest with similar clinical and laboratory findings. Disseminated fungal infections require early detection at imaging because they can be fatal if not promptly treated. Familiarity with the epidemiology, pathogenesis, clinical manifestations, imaging features, and treatment of hepatic infections can aid in radiologic diagnosis and guide appropriate patient care. (©)RSNA, 2016.

Oxidized regenerated cellulose resembling vaginal cuff abscess

INTRODUCTION

Application of oxidized regenerated cellulose is commonly performed in laparoscopy to achieve hemostasis during surgery. The appearance of an abscess resembles oxidized regenerated cellulose, causing imaging studies to be difficult to interpret.

CASE DESCRIPTION

We describe the cases of 3 patients who underwent oxidized regenerated cellulose placement during laparoscopic gynecologic surgery. They subsequently presented with signs and symptoms resembling an abscess. Computed tomographic imaging can be challenging to interpret in such cases; radiologic findings can be used to differentiate between the characteristics of oxidized regenerated cellulose and those of abscess formation on the vaginal cuff.

DISCUSSION

Oxidized regenerated cellulose has an appearance that often mimics postsurgical abscess formation. There are distinct characteristics that distinguish both findings. It is essential that patients' records accurately describe the presence and location of regenerated oxidized cellulose when placed intraoperatively, and this information must be relayed to the interpreting radiologist to facilitate medical diagnosis and guide clinical management.

Imaging of the postoperative liver: review of normal appearances and common complications

Several benign and malignant liver diseases may require surgical treatment for cure, including anatomical resections based on the segmental anatomy of the liver, non-anatomical (wedge) resections, and surgical management of biliary cysts. The type of surgery depends not only on the location and the nature of the disease, but also on the expertise of the surgeon. Whereas ultrasonography is often the first-line imaging examination in case of suspected postoperative complication, multidetector computed tomography (MDCT) is of greater value for identifying normal findings after surgery, early postoperative pathologic fluid collections and vascular thromboses, and tumor recurrence in patients who have undergone hepatic surgery. Magnetic resonance cholangiopancreatography (MRCP) is the imaging modality of choice for depicting early postoperative bile duct injuries and ischemic cholangitis that may occur in the late postoperative phase. Both MDCT and MRCP can accurately depict tumor recurrence. Radiologists should become familiar with these surgical procedures to better understand postoperative changes, and with the normal imaging appearances of various postoperative complications to better differentiate between complications and normal findings.

Observed outcomes on the use of oxidized and regenerated cellulose polymer for breast conserving surgery - A case series

BACKGROUND

Oxidized regenerated cellulose polymer (ORCP) may be used for reshaping and filling lack of volume in breast-conserving surgery (BCS). The study aimed to observe both the aesthetic and diagnostic outcomes in patients with different age, BMI, breast volume, and breast tissue composition over 36 months after BCS with ORCP.

PATIENTS AND METHODS

18 patients with early breast cancer and with proliferative benign lesions underwent BCS with ORCP that was layered in three-dimensional wafer, and placed into the Chassaignac space between the mammary gland and the fascia of pectoralis major with no fixation. After surgery, patients started a clinical and instrumental 36-month follow-up with mammography, ultrasonography, magnetic resonance imaging (MRI) and cytological examination with fine needle aspiration when seroma occurred.

RESULTS

Below the median age of 66 years old no complications were observed even in case both of overweight, and large breasts with low density. Over the median age seromas occurred with either small or large skin retraction, with the exception of 1 patient having quite dense breasts and low BMI, which had no complications. In elderly patients, 1 case with quite dense breasts and high BMI showed severe seroma and skin retraction, while 1 case with low BMI and less dense breasts highlighted milder complications.

CONCLUSION

During 36 months after BCS with ORCP, a significant correlation between positive diagnostic and aesthetic outcomes and low age, dense breasts, and low BMI of patient was observed. Despite of the few number of cases, either low BMI, or high breast density improved the aesthetic outcomes and reduced the entity of complications even in the elderly patients.

Intraovarian oxidized cellulose (Surgicel) mimicking acute ovarian pathology after recent pelvic surgery

Oxidized regenerated cellulose (Ethicon Surgicel) is often used during surgery to achieve hemostasis. The appearance of Surgicel on postoperative computed tomography (CT) may be mistaken for abscess. Meanwhile, the literature regarding its ultrasound appearance remains scant. We report the CT and sonographic appearances of Surgicel in the right ovary of a 21-year-old woman presenting to the emergency department with pelvic pain 7 days after ovarian cystectomy. The patient was discharged home with only supportive measures, and follow-up ultrasound obtained 26 days later demonstrated resolution of the sonographic abnormality. This case stresses the importance of familiarity with common imaging appearances of topical hemostatic agents and the need to correlate radiologic findings with the patient's clinical condition and prior operative reports to identify patients suitable for conservative management.

MDCT of complications and common postoperative findings following penetrating torso trauma

Victims of penetrating torso trauma often present with findings that necessitate emergent exploratory laparotomy, precluding scanning with multidetector computed tomography (MDCT) until the postoperative period. This article reviews the wide range of complications as well as expected findings that may be encountered at MDCT performed postoperatively. Little has been written to guide the radiologist in interpreting these often complex and potentially confusing studies.

Safety and usability of hemostats, sealants, and adhesives

Hemostats, sealants, and adhesives are an integral part of surgical patient care. Nurses who have knowledge about these agents can better help ensure safe, efficient surgical patient care. As a caregiver and patient advocate, the perioperative nurse must understand the most current information about these agents and be prepared to facilitate the transfer of this knowledge to all caregivers. Information about these agents, including the contraindications, warnings, and precautions associated with their use as well as their preparation and application, is provided here. Algorithms designed to clarify the best options for using hemostats, sealants, and adhesives are included as well.

Imaging of abdominal and pelvic surgical and postprocedural foreign bodies

Every form of medical and surgical treatment, even the most trivial one, carries with it some chance of complications. This risk is usually small, and the benefit of the treatment should clearly outweigh the risk. Treatment-related complications may occur, however, presenting either soon after the intervention or remote from it. In this review, the focus is on imaging findings of surgical materials used in abdominal surgery, and of a wide array of implanted abdominal devices. The pertinent complications of these devices and of retained surgical objects are highlighted and illustrated.

Imaging features of a gelatin-thrombin matrix hemostatic agent in the intracranial surgical bed: a unique space-occupying pseudomass

BACKGROUND AND PURPOSE

Absorbable gelatin-thrombin matrix is increasingly being used in neurosurgical procedures; unlike other hemostats, the stable matrix is left undisturbed and fills the surgical bed after achieving hemostasis. We investigated the immediate postoperative radiographic imaging appearance of the gelatin-thrombin matrix in intracranial operative beds.

MATERIALS AND METHODS

Thirty-one consecutive patients (18 men, 13 women; mean age, 59 years) with 34 surgical cavities, had 31 brain MRIs and 9 head CTs performed ≤ 48 hours postoperatively. They were retrospectively reviewed. Images were evaluated independently by 2 neuroradiologists blinded to the surgical techniques. Surgical beds were evaluated for the presence of the gelatin-thrombin matrix, which appeared as pseudoair material (Hounsfield units ≤ -100) on CT, had characteristic T2-hypointense speckles in a T2-hyperintense background, and demonstrated complete gradient-recalled echo hypointensity on MR imaging. To determine the diagnostic performance of imaging features for the detection of the gelatin-thrombin matrix, the Fisher exact test for the association between imaging features and the presence of the gelatin-thrombin matrix and κ analysis for interobserver agreement were performed.

RESULTS

Hemostasis was achieved with standard methods in 12 surgical beds and with the gelatin-thrombin matrix in 22 beds. Interobserver agreement was substantial. The gelatin-thrombin matrix demonstrated pseudoair hypoattenuation (88% sensitivity, 100% specificity, 90% accuracy; P = .067, κ = 0.74) and distinctive T2-hypointense speckles in a background of T2-hyperintensity (81% sensitivity, 85% specificity, 82% accuracy; P = <.001, κ = 0.76). Combined characteristic T2 speckles and gradient-recalled echo hypointensity increased the specificity (81% sensitivity, 100% specificity, 88% accuracy; P = < .001).

CONCLUSIONS

The unique appearance (pseudoair on CT, T2 speckles with gradient-recalled echo hypointensity) of the gelatin-thrombin matrix should not be mistaken for gossypiboma, pneumocephalus, and/or hematoma.

Cotton-Derived Oxidized Cellulose in Minimally Invasive Thoracic Surgery

Objective

The aim of this study was to identify resorption, clinical performance, and safety of cotton-derived oxidized cellulose gauze applied as a hemostat in minimally invasive oncologic thoracic surgery.

Methods

This is a pilot prospective noncomparative observational human in vivo study. A piece of cotton-derived oxidized cellulose gauze measuring 5 × 20 cm was inserted into the subcarinal space of patients with potentially resectable lung carcinoma at the time of video-assisted mediastinoscopic lymphadenectomy and reexamined several days later for macroscopic and histologic evaluation at the time of subsequent lung resection. The primary endpoint was the local situation at the implantation site described by cellulose remnants, fluid collections, and adhesions. The secondary endpoint was safety, described by the number of adverse events and surgical reinterventions.

Results

Twenty-five consecutive eligible patients with potentially resectable lung carcinoma were included. The desired hemostatic effect was achieved in all cases. No adverse events were observed. At re-exploration 10.5 (5–28) days later, the cellulose gauze was found to lose its solid structure from the fifth day on. Remnants were last detected 14 days after insertion. The implantation site exhibited no inflammatory changes and a remarkable small amount of fluid collections and adhesions.

Conclusions

Mediastinal application of cotton-derived oxidized cellulose is safe and effective. A piece of gauze measuring 5 × 20 cm seems to be absorbed completely within 15 days, thus precluding any interference with oncologic restaging and follow-up. The absence of relevant adhesions facilitates further surgical procedures. Larger comparative confirmatory studies are required. For large-scale resorption studies, our clinical model should be translated into a porcine model.

Oxidized regenerated cellulose imitating pelvic abscess

BACKGROUND

Oxidized regenerated cellulose is a topical hemostatic agent that is used commonly in abdominal and pelvic surgery. Although oxidized regenerated cellulose mimicking an abscess has been reported after different operations, little is known about its side effects after gynecologic surgery.

CASES

Two women were diagnosed with postoperative abscess and intra-abdominal oxidized regenerated cellulose was identified as an abscess or as part of an abscess on computed tomography imaging. Both women recovered after treatment with antibiotics with and without drainage.

CONCLUSION

Oxidized regenerated cellulose may be mistaken for an abscess or as part of an abscess on imaging studies. It is important to reveal information about oxidized regenerated cellulose use to the imaging department.

Oxidized regenerated cellulose granuloma mimicking recurrent mass lesion after laparoscopic nephron sparing surgery

INTRODUCTION

Achieving hemostasis in laparoscopic nephron sparing surgery (LNSS), a technically demanding procedure, is challenging. Absorbable hemostatic agents, such as oxidized regenerated cellulose (ORC) are frequently used for hemostasis in laparoscopic nephron sparing surgery. Retention of this material is a very rare situation.

PRESENTATION OF THE CASE

We are presenting a case of ORC granuloma after nephron sparing surgery for renal cell carcinoma (RCC) mimicking recurrent renal mass. A 50-year-old woman diagnosed with upper pole renal mass underwent laparoscopic nephron sparing surgery. Oxidized regenerated cellulose was used to achieve hemostasis for an oozing from the perirenal tissue. Resection confirmed RCC. Imaging at 6th month follow-up revealed a lesion with contrast enhancement at the location of the adrenal gland. Positron emission tomography suggested inflammation or metastasis. Histopathological evaluation of the mass revealed foreign body granuloma.

DISCUSSION

Laparoscopic nephron sparing surgery is becoming a standardized treatment of select renal tumors. Hemostatic agents, such as ORC, are frequently used to minimize complications in LNSS. In case of ORC application, which is completely absorbed in 8 weeks, to or to a location with close proximity to the primary resection site, surgical granuloma formation should be considered. However its use should not be discouraged and biopsy may be considered for definitive diagnosis.

CONCLUSION

Oxidized regenerated cellulose granuloma may mimic different entities such as including invasive carcinoma. Thus it is of utmost importance, if ORC was used during LNSS, the location and use of this material should be noted precisely.

Hepatic gas: widening spectrum of causes detected at CT and US in the interventional era

The spectrum of causes of hepatic gas detected at computed tomography (CT) and ultrasonography (US) is widening. There are many iatrogenic and noniatrogenic causes of hepatic parenchymal, biliary, hepatic venous, and portal venous gas. Hepatic gas may be an indicator of serious acute disease (infarct, infection, abscess, bowel inflammation, or trauma). In other clinical scenarios, it may be an expected finding related to therapeutic interventions (such as surgery; hepatic artery embolization for a tumor or for active bleeding in acute trauma cases; percutaneous tumor ablation performed with radiofrequency, cryotherapy, laser photocoagulation, or ethanol). In some cases, hepatic gas is an incidental finding of no clinical significance. Familiarity with the expanding list of newer intervention-related causes of hepatic gas detected at CT and US, knowledge of the patient's clinical history, and a careful search for associated clues on images are all factors that may allow the radiologist to better determine the clinical relevance of this finding.

Foreign objects encountered in the abdominal cavity at CT

Foreign objects are not infrequently seen at computed tomography (CT) of the abdomen and pelvis and may pose a diagnostic challenge to the radiologist, who must recognize the object, characterize its nature and location, and determine its clinical significance. Most foreign objects are incidentally detected at CT, but they may mimic a wide range of pathologic conditions. Some foreign objects (eg, an object that has been swallowed either intentionally or unintentionally) are the cause of the patient's signs and symptoms and require prompt medical attention. Other objects, such as a sponge or surgical instrument that has been retained postoperatively, may have medicolegal consequences. Furthermore, certain objects, such as intentionally concealed drug packets, may go undetected unless a high degree of suspicion exists and appropriate window settings are used to review the study. The radiologist should be familiar with the wide range of foreign objects that may be encountered at abdominopelvic CT, be able to recognize them promptly, and understand their implications for patient treatment.

Evolution of hemostatic agents in surgical practice

Objective:

Topical hemostatic agents are used in a wide variety of surgical settings, and the evolution of this class of surgical tools is an interesting topic. We reviewed and outlined the historical progress of topical hemostats into present day surgery and urology, and highlight opportunities for future research.

Materials and Methods:

A MEDLINE search of all available literature concerning several classes of topical hemostatic agents was performed. Fibrins sealants, Gelatin sponge hemostatics, cyanoacrylate adhesives, oxidized regenerated cellulose, and microfibrillar collagen were included. References were chosen from a broad range of surgical literature.

Results:

Topical hemostatic agents have historically taken advantage of a wide variety of mechanisms for hemostasis. Fibrin sealants have a rich history and large potential for further applications. Gelatin sponge hemostatics have been widely used since their introduction, but have changed little. Cyanoacrylate adhesives have a unique mechanism and opportunity for novel applications of existing products. Oxidized cellulose was original in the use of plant-based components. Microfibrillar collagen hemostats have evolved to a wide variety of formats.

Conclusions:

A review of the evolution of topical hemostatic agents highlights opportunities for potential novel research. Fibrin sealants may have the most opportunity for advancement, and understanding the history of these products is useful. With the drive in urology for minimally invasive surgical techniques, adaptation of topical hemostatic agents to this surgical approach would be valuable and offers an opportunity for novel contributions.

Commonly encountered foreign bodies and devices in the female pelvis: MDCT appearances

OBJECTIVE

The objective of this article is to illustrate the MDCT appearances of several commonly encountered foreign bodies and devices in the female pelvis.

CONCLUSION

The presence of a foreign body or device in the female pelvis can be a potential source of confusion to radiologists, particularly to the inexperienced reader. Familiarity with the normal appearances and locations of these devices on MDCT allows their accurate identification and detection of associated complications.

Subcarinal collection following mediastinoscopy: a normal post-procedural CT finding

AIM

To determine the frequency with which a subcarinal collection is present at computed tomography (CT) following mediastinoscopy and to determine the CT features of the collection.

MATERIALS AND METHODS

All patients who underwent uncomplicated mediastinoscopy during a 1-year period were retrospectively identified. This list was cross-referenced to determine those patients who also underwent CT within 15 days after the procedure. Each post-mediastinoscopy CT examination was assessed in consensus by three fellowship-trained thoracic radiologists for the presence of subcarinal abnormalities, which were also characterized in terms of their size and density. Additional CT findings were recorded, including tracheobronchial wall thickening, paratracheal collections, mediastinal fat stranding, and mediastinal air.

RESULTS

The study cohort included 10 patients (seven men and three women) with mean age of 65 years (range 49-81 years). CT was performed a mean of 11 days following mediastinoscopy. The most common CT finding was an oval subcarinal collection in nine of 10 cases (size 1.1-3.2 cm). In all nine cases, the subcarinal collections were consistently lower in attenuation than the subcarinal lymph node in the same region on the pre-procedure CT examination. Other CT findings included anterior tracheobronchial wall thickening (n=7); paratracheal collection (n=6); mediastinal fat stranding (n=6); and mediastinal air in (n=4) cases.

CONCLUSION

A subcarinal collection was identified in 90% of cases following mediastinoscopy. Its rapid development and characteristic appearance help to distinguish it from a lymph node.