Magnetic-assisted detection and extraction of dispersed metallic foreign bodies in the abdominal cavity: A case report

Abstract

BACKGROUND

Gastrointestinal foreign bodies represent a significant clinical challenge in emergency and surgical settings. While accidental ingestion predominates in healthy adults, intentional ingestion is frequently observed in pediatric, psychiatric, and incarcerated populations. Metallic sewing needles, characterized by their sharp morphology and high mobility, pose particular risks of visceral injury and complications due to their penetrative potential. Although preoperative imaging facilitates initial localization, subsequent migration of multiple needles complicates therapeutic interventions, increasing procedural complexity and patient risk.

CASE SUMMARY

We present a novel application of magnetic-assisted localization in managing a complex case of intentional ingestion of 30 metallic sewing needles in a psychiatric patient. The widespread distribution of needles throughout the gastrointestinal tract necessitated an innovative surgical approach. Intraoperative implementation of cylindrical magnetic localization technology enabled precise identification and successful extraction of all foreign bodies while minimizing tissue trauma.

CONCLUSION

Magnetic-assisted localization represents an effective and safe technique to manage multiple magnetic gastrointestinal foreign bodies. This approach offers significant advantages in complex cases, particularly for needle-like metallic objects, and warrants consideration as a valuable tool in gastrointestinal surgery.

Key Words: Magnet; Foreign body; Metal; Laparotomy; Gastrointestinal; Case report

Core Tip: In cases involving the ingestion of multiple scattered magnetic needle-like foreign bodies in the digestive tract, cylindrical magnetic rods can be utilized to explore physiological bends or narrow areas prone to obstruction, facilitating precise localization and removal of the foreign bodies.

INTRODUCTION

Gastrointestinal foreign bodies are frequently encountered in emergency and gastrointestinal surgery departments. While accidental ingestion is more common among healthy adults, intentional ingestion is often observed in infants, psychiatric patients, and prisoners. Metallic sewing needles, due to their slender, sharp, and highly penetrative nature, pose a significant risk of migration and organ damage caused by gastrointestinal motility. Although preoperative imaging can assist in locating foreign bodies, needle migration—particularly in cases involving multiple needles—complicates treatment and increases clinical risks.

This report describes a rare case of a psychiatric patient who ingested 30 metallic sewing needles of varying lengths and sizes, dispersed throughout the gastrointestinal tract. The large quantity and widespread distribution of the needles rendered intraoperative retrieval particularly challenging. To ensure accurate localization and complete removal, cylindrical magnetic-assisted positioning technology was utilized during surgery, successfully extracting all foreign bodies. This article highlights the clinical approach and treatment experience associated with this unusual case, offering valuable insights into the management of similar high-risk scenarios.

CASE PRESENTATION

Chief complaints

A 55-year-old woman presented with upper abdominal pain following the ingestion of foreign objects.

History of present illness

The patient reported swallowing metallic sewing needles 5 days prior but was unable to specify the exact number. She experienced intermittent upper abdominal pain, accompanied by nausea, vomiting, and melena. The vomitus consisted primarily of gastric contents, without regurgitation or belching. She denied symptoms such as fever, diarrhea, or jaundice.

History of past illness

Past medical history included visual impairment, with the patient being blind in the left eye and only having light perception in the right eye. Information provided by family members showed that the patient had a history of depression and anxiety for nearly 10 years, but had not received standardized psychological treatment.

Personal and family history

No significant clinical findings were reported.

Physical examination

The patient had stable vital signs, a symmetrical and flat abdomen, and no visible peristaltic waves. The abdomen was soft with tenderness but without rebound tenderness, and no palpable masses were detected. Bowel sounds were decreased and absent in some areas.

Laboratory examinations

Laboratory tests did not reveal a significant inflammatory response.

Imaging examinations

Four days after foreign body ingestion, an upright abdominal X-ray revealed multiple high-density metallic foreign bodies in the abdomen. A subsequent chest X-ray showed no obvious abnormalities. A repeat upright abdominal X-ray (Figure 1) displayed numerous scattered high-density metallic sewing needles in the abdominal cavity. Abdominal computed tomography (CT) scanning and three-dimensional localization confirmed that some needle-like objects had penetrated the gastrointestinal wall into the peritoneal cavity (Figure 2). Since the onset of symptoms, the patient had experienced poor mental status and sleep quality, decreased appetite, but normal urination, with no significant weight change.

Figure 1 Preoperative abdominal radiography demonstrating multiple metallic foreign bodies distributed in the abdominal cavity.

Figure 2 Axial computed tomography imaging of metallic foreign body distribution in the abdominal cavity (orange arrows).

FINAL DIAGNOSIS

Foreign bodes distributed throughout the entire digestive tract.

TREATMENT

Preoperative preparation

Comprehensive preoperative evaluations were conducted, revealing no surgical contraindications. Preoperative imaging indicated an uncertain number and widespread distribution of metallic sewing needles within the gastrointestinal tract, complicating intraoperative localization. A cylindrical neodymium-iron-boron magnet, (20 cm in height, 1 cm in diameter) was selected for magnetic-assisted localization. The magnet was sterilized using high-pressure steam prior to surgery.

Surgical procedure

Under general anesthesia, a midline abdominal incision was made. Referring to preoperative imaging examination for the location of the needle-like foreign bodies, systematic exploration of the abdominal cavity was conducted in a sequential manner.

Initial exploration revealed a metallic needle, approximately 4 cm in length, lodged between the liver and stomach ligaments. The needle was carefully removed, and hemostasis was achieved on the liver surface. A second metallic needle, also approximately 4 cm in length, was found penetrating the greater curvature of the stomach into the liver. After extraction, the gastric wall was closed with full-thickness sutures.

Further dissection and exposure of the duodenum identified four metallic needles protruding from the descending portion of the duodenum, with two oriented toward the abdominal side and two toward the posterior side, penetrating the peritoneum. All four needles were cautiously removed. A cylindrical magnet was then utilized to explore the duodenal descending portion and junction with the horizontal portion. Slight bulging of the intestinal wall near the magnet indicated the presence of metallic needles. Two additional needles were extracted from the original perforation site and the two perforation sites, which were subsequently sutured and reinforced.

The cylindrical magnet was further employed to explore the gastric body, revealing several metallic needles that had not caused perforation. Six metallic needles were identified exiting the anterior wall of the stomach, away from blood vessels. All puncture sites were closed with full-thickness sutures and reinforced.

Exploration of the small intestine using the cylindrical magnet revealed no significant bulging or tension in the intestinal wall. Attention was then directed to the colon (Figure 3), where multiple metallic needles were identified in the cecum and ascending colon. Ten needles were removed from the hepatic flexure of the ascending colon, and the perforations were sutured using the same technique. Further exploration of the colon identified one metallic needle at the junction of the descending colon and sigmoid colon, which was removed, and the perforation sutured.

Figure 3 Schematic representation of magnetic foreign body localization procedure. A: Manual exploration of the gastrointestinal tract with the cylindrical magnet; B: Baseline colonic morphology without magnetic intervention; C: Magnetic-induced colonic wall deformation indicating foreign body localization.

Following complete exploration of the pelvic cavity, intraoperative C-arm X-ray imaging was performed to identify any missed metallic foreign bodies. High-density shadows were detected at the lower end of the esophagus, upper abdomen midline, left upper abdomen, right upper abdomen, and right lower abdomen. These areas were meticulously explored using the cylindrical magnet, resulting in the extraction of five additional needles from the lower esophagus, horizontal segment of the duodenum, hepatic flexure of the colon, splenic flexure of the colon, and cecum. Repeat C-arm imaging confirmed the absence of any remaining metallic foreign bodies in the chest, abdomen, or pelvis.

The abdominal cavity was irrigated, and hemostasis was confirmed. All gastrointestinal incisions were re-examined to ensure precise closure and intestinal patency. The procedure was successfully completed in 3 hours and 15 minutes, with an estimated blood loss of 30 mL. A total of 30 metallic needles were removed (Figure 4).

Figure 4 Intraoperative findings of 30 metallic sewing needles retrieved from the gastrointestinal tract.

OUTCOME AND FOLLOW-UP

Enteral nutrition was initiated on postoperative day 5, and the patient was discharged 10 days after surgery. After a follow-up period of 3 years and 8 months, the patient remains in good health, with no surgery-related complications.

DISCUSSION

The epidemiology of gastrointestinal foreign bodies exhibits significant geographic and demographic variations, with needle ingestion representing a particularly rare clinical entity. The clinical manifestations and complications associated with such foreign bodies are influenced by multiple factors, including their physical properties, chemical composition, and duration of retention duration. Specific patient populations, particularly those with psychiatric comorbidities or developmental disorders, demonstrate distinct clinical presentations[1-3]. While metallic needle ingestion is uncommon compared to other sharp objects (e.g., fish bones), it carries substantial risk of severe complications[4,5]. Pediatric cases typically result from accidental ingestion, whereas adolescent and adult cases often correlate with underlying psychiatric conditions.

Current diagnostic modalities primarily include radiographic imaging, CT, and endoscopy. Radiography remains the first-line diagnostic tool, though CT provides superior spatial resolution for precise localization. Notably, magnetic resonance imaging is contraindicated due to potential ferromagnetic displacement risks. Contemporary management strategies achieve successful non-surgical removal in 90%-95% of cases through spontaneous passage or endoscopic intervention[6-10]. Surgical management is reserved for cases refractory to conservative approaches or those presenting with complications.

The management of multiple needle foreign bodies presents unique challenges due to their widespread distribution and potential for transmural migration. Our magnetic localization technique capitalizes on the ferromagnetic properties of metallic needles, allowing for precise intraoperative identification through characteristic intestinal wall protrusion upon magnetic approximation. This approach requires meticulous technique to prevent iatrogenic injury during extraction.

Intraoperative endoscopy (including gastroscopy and colonoscopy) assistance provides multiple advantages beyond diagnostic confirmation, including real-time monitoring, complication assessment, and minimally invasive extraction capabilities[11]. The integration of endoscopic techniques with traditional surgical approaches has been shown to reduce operative morbidity while maintaining high success rates[12,13].

The present case illustrates several critical considerations in managing multiple metallic foreign bodies. The patient’s psychiatric history and the sheer volume of ingested needles (n = 30) represent an exceptionally rare clinical scenario. The needles’ distribution throughout the gastrointestinal tract, coupled with their sharp morphology, created substantial risk of perforation and adjacent organ injury. Preoperative imaging, while essential for initial localization, was limited by metallic artifact and needle superposition, underscoring the need for advanced intraoperative localization techniques.

Current guidelines emphasize that foreign body impaction typically occurs at anatomical narrowings or angulations, with sharp objects posing particular perforation risks[14]. In our case, intraoperative findings confirmed this pattern, with > 70% of needles located at high-risk anatomical sites. Notably, the absence of radiographic pneumoperitoneum did not exclude perforation, likely due to the self-sealing nature of small-caliber needle punctures.

The implementation of magnetic-assisted localization addressed several critical challenges: (1) Real-time dynamic tracking of mobile foreign bodies; (2) Minimization of gastrointestinal incisions through transmural magnetic attraction; (3) Reduction of radiation exposure compared to fluoroscopic guidance; and (4) Enhanced surgical precision and safety.

While magnetic localization has been described in other surgical contexts[15,16], the application thereof to multiple gastrointestinal needle foreign bodies represents a novel advancement. Previous reports have demonstrated the utility of magnetic techniques in pediatric cases[17,18] and airway management[19], while others have highlighted its advantages in extremity foreign body removal[20]. The compass-assisted detection method described by Liu et al[21] shares conceptual similarities with our approach, though our technique offers superior intraoperative precision.

Technical considerations include the use of non-ferromagnetic surgical instruments to minimize interference[22-24]. The integration of magnetic localization with minimally invasive principles offers multiple benefits: reduced operative time; minimized tissue trauma; enhanced postoperative recovery; and improved clinical outcomes.

This case demonstrates that magnetic-assisted localization represents a significant advancement in the management of multiple gastrointestinal metallic foreign bodies. The technique’s safety profile, combined with its technical advantages, suggests its potential as a standard approach in similar challenging cases. Future studies should focus on optimizing magnetic parameters and developing specialized instrumentation to further enhance the efficacy and safety of this promising technique.

CONCLUSION

For patients with a significant number of ingested magnetic gastrointestinal foreign bodies, traditional imaging techniques may be insufficient for accurate localization. Intraoperative magnetic-assisted exploration enhances the efficiency of foreign body extraction and minimizes risk. Prompt surgical intervention is essential to prevent further damage to vital organs.

ACKNOWLEDGEMENTS

We sincerely thank the Northwest Institute for Nonferrous Metal Research for their support in processing the Nv-Fe-P material and manufacturing the intraoperative magnetic-assisted equipment. We also extend our gratitude to the staff of the Medical Record Information Management Department for their valuable assistance.