An Ultrasound-Guided Fine Needle Aspiration (US-FNA) is a quick, safe, and minimally invasive procedure used to sample fluid or cells from a breast mass, cyst, or nearby lymph node. By utilizing real-time ultrasound imaging, the radiologist can visualize the target continuously, ensuring precise needle placement while protecting surrounding healthy tissue and minimizing discomfort.
Pre-Procedure Preparation
Medication Review: Inform your doctor if you are taking blood thinners (e.g., aspirin, warfarin, clopidogrel, or newer oral anticoagulants) or anti-inflammatory drugs. You may be advised to briefly adjust your dosage or pause certain medications prior to the procedure.
Clothing Choice: Wear a comfortable two-piece outfit (a top with trousers or a skirt) so you only need to remove your upper garments during the exam.
Dietary Guidelines: Fasting is generally not required; you may eat and drink normally before your appointment.
Skin Care: Do not apply powder, lotion, or deodorant to the breast or underarm area on the day of the procedure, as these can interfere with ultrasound image clarity.
Step-by-Step Procedure
The overall appointment usually takes 15 to 30 minutes, while the needle insertion and aspiration process itself takes only a few minutes.
[1. Positioning & Scanning] ──► [2. Sterilization & Anesthesia] ──► [3. Ultrasound-Guided Aspiration] ──► [4. Compression & Bandaging]
Positioning & Initial Scan: You will lie comfortably on an examination couch, usually on your back or slightly tilted. Ultrasound gel is applied, and the radiologist performs a brief scan to pinpoint the exact position, size, and depth of the target lesion.
Skin Sterilization: The skin over the target area is cleansed with an antiseptic solution to maintain a sterile field.
Local Anesthesia (Optional): A small amount of local anesthetic may be injected into the skin to numb the entry site. Because FNA uses a very thin needle (similar to a standard blood test needle), local anesthesia is minimal or sometimes omitted for simple, superficial fluid cysts.
Real-Time Guided Aspiration
Holding the ultrasound transducer in one hand, the radiologist advances a fine-gauge needle (21G–25G) attached to a syringe directly into the lesion using the other hand.
The needle tip is continuously monitored on the ultrasound display as it navigates into the target.
For Cysts: Fluid is drawn into the syringe until the cyst completely collapses on the screen.
For Solid Lesions / Lymph Nodes: The needle is gently moved back and forth within the target to collect a small sample of cells via capillary action or light suction.
Needle Removal & Pressure: Once the sample is collected, the needle is withdrawn. Direct, firm pressure is applied to the puncture site for 3 to 5 minutes to prevent internal bleeding and minimize bruising.
Bandage Application: The site is cleaned and covered with a small sterile bandage or Steri-Strip. Stitches are not required.
Post-Procedure Care & Recovery
Daily Activities: You may return to normal daily routines immediately after the procedure. However, avoid heavy lifting, strenuous upper-body exercise, or vigorous contact sports for 24 hours.
Pain Management: Mild soreness or slight localized bruising is normal. Over-the-counter acetaminophen (paracetamol) can be taken for discomfort. Avoid aspirin or non-steroidal anti-inflammatory drugs (NSAIDs) immediately after the procedure unless prescribed, as they can increase the risk of bruising.
Wound Care: Keep the bandage clean and dry for 24 hours, after which it can be removed.
Cold Compress: Applying a cold ice pack wrapped in a towel for 10–15 minutes at a time can help reduce localized swelling.
Benefits and Potential Risks
Key Benefits
Minimally Invasive: Leaves no surgical scar and requires no general anesthesia.
Real-Time Accuracy: Ultrasound guidance guarantees precise positioning directly inside the lesion.
Immediate Relief: Draining a tense, painful fluid cyst provides instant symptom relief.
Zero Recovery Downtime: Patients can immediately resume work and regular activities.
Potential Risks & Complications
US-FNA is extremely safe, with a very low complication rate:
Bruising (Hematoma): Minor localized bruising is the most common side effect and typically resolves within several days.
Infection: Extremely rare (<0.1%) due to strict sterile technique.
Inconclusive Yield: Occasionally, an FNA may yield insufficient cells for a definitive diagnosis, requiring a follow-up Core Needle Biopsy (CNB).
What Happens to the Samples?
Fluid Samples: It is sent to the pathology laboratory for cytological evaluation.
Cellular Samples: Aspirated cells are smeared onto glass slides, preserved, and sent for microscopic examination by a pathologist.
Results Timeline: Pathology reports are typically ready within 5 to 7 business days. Your attending physician will review the results with you and determine whether any further monitoring or treatment is required.
超聲波引導下細針穿刺細胞學檢查（US-FNA）：程序概述與注意事項
超聲波引導下細針穿刺細胞學檢查（US-FNA） 是一種快速、安全且微創的檢查程序，用於從乳房腫塊、囊腫（水瘤）或附近淋巴結抽取液體或細胞樣本。藉由實時超聲波影像，放射科醫生能全程持續觀察目標位置，確保精準進針，同時保護周圍健康組織並將不適感降至最低。
檢查前準備
藥物審查：若您正在服用阿士匹靈（Aspirin）、華法林（Warfarin）、氯吡格雷（Clopidogrel）或新型口服抗凝血藥等薄血藥（抗凝血劑）或抗炎藥物，請提前告知醫生。在檢查前，醫生可能會建議您暫時調整藥量或停用部分藥物。
衣著選擇：建議穿著舒適的分體式衣服（上衣配長褲或裙子），以便在檢查期間只需脫去上衣。
飲食指引：通常無需禁食，檢查前可正常飲食。
皮膚護理：檢查當天請勿在乳房或腋下部位塗抹香粉、護膚霜或止汗劑，以免影響超聲波影像的清晰度。
檢查步驟與過程
整個預約過程通常需時 15 至 30 分鐘，而實際進針及抽吸過程只需數分鐘。
[1. 定位與掃瞄] ──► [2. 消毒與麻醉] ──► [3. 超聲波引導抽吸] ──► [4. 按壓與包紮]
體位擺放與初步掃瞄：您將舒適地平躺在檢查床上，通常呈仰臥或身體微微傾斜。醫生會在檢查部位塗上超聲波導電凝膠，並進行初步掃瞄，以精確定位目標病變的位置、大小及深度。
皮膚消毒：使用消毒藥水清潔目標區域的皮膚，以保持無菌狀態。
局部麻醉（可選）：醫生可能會在進針點的皮膚注射少量局部麻醉藥以減輕痛楚。由於 FNA 使用極細的針頭（與一般抽血針頭相若），局部麻醉藥的使用量極少，對於簡單且位置較淺的液體囊腫，有時甚至無需麻醉。
實時引導抽吸
放射科醫生一手持超聲波探頭，另一手將連接針筒的細針（21G–25G）直接推進至病變位置。
在超聲波螢幕上，針尖推進過程會受到實時監控。
針對囊腫（水瘤）：液體會被抽入針筒內，直至螢幕上顯示囊腫完全萎縮塌陷。
針對實質性病變／淋巴結：針頭會在目標組織內輕微前後移動，透過毛細管作用或輕微負壓抽取少量細胞樣本。
拔針與按壓止血：完成採樣後隨即拔出針頭。工作人員會在穿刺點直接緊壓止血 3 至 5 分鐘，以防止內部出血並減少瘀青。
包紮：清潔穿刺部位並貼上小型無菌膠布或防水貼。此程序無需縫針。
術後護理與康復
日常活動：檢查完成後可立即恢復日常活動。但請在 24 小時內避免提舉重物、劇烈上半身運動或碰撞性運動。
疼痛管理：出現輕微酸痛或局部輕微瘀青屬正常現象。如有不適，可服用撲熱息痛（Paracetamol / Acetaminophen）止痛。除非醫生處方，否則請避免在術後立即服用阿士匹靈或非類固醇消炎止痛藥（NSAIDs），以免增加瘀青風險。
傷口護理：請保持包紮膠布清潔乾燥 24 小時，之後即可移除。
冰敷：可使用布包裹冰袋進行局部冰敷，每次 10 至 15 分鐘，有助減輕局部腫脹。
好處與潛在風險
主要好處
微創安全：不留手術疤痕，亦無需全身麻醉。
實時精準：超聲波即時引導能確保針頭精確定位於病變內部。
即時紓緩：抽乾張力大、引起疼痛的液體囊腫能即時減輕症狀。
無需休養：患者可於完成檢查後立即恢復工作及正常生活。
潛在風險與併發症
US-FNA 極為安全，併發症發生率非常低：
瘀青（血腫）：局部輕微瘀青是最常見的副作用，通常會在數天內自然消退。
感染：由於嚴格執行無菌操作，發生率極低（<0.1%）。
樣本不足：偶爾 FNA 抽取的細胞數量可能不足以作出明確診斷，屆時可能需要進行後續的粗針組織活檢（CNB）。
樣本處理與報告
液體樣本：會送往病理實驗室進行細胞學檢查。
細胞樣本：抽取的細胞會塗抹於玻璃片上固定，並送往病理科由病理科醫生在顯微鏡下進行分析。
報告時間：病理報告通常在 5 至 7 個工作天 內完成。您的主診醫生會與您討論報告結果，並決定是否需要進一步監測或治療。