• Current Optics and Photonics
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• 제5권5호
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• pp.532-537
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• 2021

We present a compact endoscopic probe in a needle form which has a fast beam-scanning capability for optical coherence tomography (OCT). In our study, a beam-scanning OCT imaging needle was fabricated with a 26G syringe needle (0.46 mm in outer diameter) and a thin OCT imaging probe based on the stepwise transitional core (STC) fiber. The imaging probe could freely rotate inside the needle for beam scans. Hence, OCT imaging could be performed without rotation or translation of the needle body. In our design, the structural integrity of the needle's steel tubing was preserved for mechanical robustness. Probing the optical signal was performed through the needle's own window formed at the end. For hand-held operation of our imaging needle, a light and compact scanner module (130 g and 45 × 53 × 60 mm³) was devised. Connected to the imaging needle, it could provide rotational actuation driven by a galvanometer. Because of its finite actuation range, our scanner module did not need a fiber rotary joint which might add undesirable complexity. The beam scan speed was 20 Hz and supported 20 frames per second at the maximum for endoscopic OCT imaging.

• 대한방사선협회지
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• 제30권1호
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• pp.58-62
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• 2004

The purpose of this study was to determine the factors influencing on the size of Radiofrequency ablation using an internally cooled needle electrodes in cattle liver. Ablation procedures involved the use of cool-tip RF system generator and internally coo

• 대한의용생체공학회:의공학회지
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• 제33권3호
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• pp.105-113
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• 2012

Biopsy is a type of histopathological examinations, in which a physician samples cells or tissues from a patient's suspicious lesion. Such a lesion frequently resides deep inside human body, and then a percutaneous biopsy is therefore performed using a thick needle with the assistance of medical imaging such as computed tomography(CT) and magnetic resonance imaging(MRI). Recently modern robotic technology is being introduced to percutaneous biopsy in order to reduce any possible human error and hazard on physicians caused by medical imaging. After medical imaging locates the exact location of lesion, an optimization algorithm plans the path for a biopsy needle. Subsequently, a robot system moves the biopsy needle to the lesion in accurate and safe way with the control of a practitioner or automatically. In this article, we try to look into the state-of-art of percutaneous biopsy using such robotic technology. We classified percutaneous biopsy robots by mechanical characteristics and by imaging technology. Then, advantage and disadvantage of each class type are described as well as the basic description, and a few representative designs for each type are introduced. Current research issues of robotized percutaneous biopsy are subjectively selected for the readers' convenience. We emphasize the basic technology of actuator and sensors compatible with imaging technology to conclude this review.

• The Korean Journal of Pain
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• 제35권3호
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• pp.345-352
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• 2022

Background: Optimal needle depth in transforaminal epidural injection (TFEI) is determined by body measurements and is influenced by the needle entry angle. Physician can choose the appropriate needle length and perform the procedure more effectively if depth is predicted in advance. Methods: This retrospective study included patients with lumbosacral pain from a single university hospital. The skin depth from the target point was measured using magnetic resonance imaging transverse images. The depth was measured bilaterally for L4 and L5 TFEIs at 15°, 20°, and 25° oblique angles from the spinous process. Results: A total of 4,632 measurements of 386 patients were included. The lengths of the left and right TFEI at the same level and oblique angle were assessed, and no statistical differences were identified. Therefore, linear regression analysis was performed for bilateral L4 and L5 TFEIs. The R-squared values of height and weight combined were higher than the height, weight, and body mass index (BMI). The following equation was established: Depth (mm) = a - b (height, cm) + c (weight, kg). Based on the equation, maximal BMI capable with a 23G, 3.5-inch, Quincke-type point spinal needle was presented for three different angles (15°, 20°, and 25°) at lumbar levels L4 and L5. Conclusions: The maximal BMI that derived from the formulated equation is listed on the table, which can help in preparations for morbid obesity. If a patient has bigger BMI than the one in the table, the clinician should prepare longer needle than the usual spinal needle.

• Journal of Dental Anesthesia and Pain Medicine
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• 제20권2호
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• pp.83-87
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• 2020

Foreign body (FB) ingestion is commonly seen in the ear nose and throat (ENT) field, with different presentations and sequelae. FBs can arrest in the upper aerodigestive tract or continue further down into either the airway tract to the bronchus or the digestive tract to the intestines. The pathway of an FB depends on the size and shape of the FB and how sharp its edges are. Since the 20th century, the use of disposable stainless-steel needles in the oral cavity has proven to be an effective and safe method for performing various intraoral procedures like dental infiltration or a root canal wash. Complications from their use are rare. Generally, dental needle breakages are caused by patients biting the needle, incorrect injection techniques, or inadequate preventative measures. The sudden movement of a patient during a procedure is one of the most common causes of breakage. Occasionally, needles are swallowed during dental procedures such as a root canal. Here, we report a case of a patient that swallowed a broken needle during a dental procedure. A few days later, the patient presented with neck pain, swelling, and a FB sensation. When the patient presented, she claimed that her symptoms had onset after consuming a meal containing duck meat. Initially, the patient was diagnosed as having ingested a duck bone. However, intraoperatively, the FB was discovered to be an injection needle that had migrated from the throat to the neck.

• 한국임상수의학회지
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• 제21권2호
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• pp.181-183
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• 2004

Hepatic mass was aspirated under the guidance with ultrasound in 9-year old female maltese with signs of anorexia, hematochezia, vomiting, depression, and abdominal distension. Radiographic and abdominal ultrasonographic examinations were performed, which revealed enlarged tubular shaped uterine mass and solitary, small round hyperechoic hepatic mass dorsal to gall bladder as an incidental finding. Ultrasound-guided fine needle aspiration was completed, but histologic confirmation should be made for definitive diagnosis by tissue core or wedge biopsy.

• 대한두경부종양학회지
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• 제31권1호
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• pp.9-13
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• 2015

Fine needle aspiration cytology as a diagnostic workup of parotid gland tumor is a simple and useful method. Although fine needle aspiration cytology could not predict accurate diagnosis in all cases, it is usually helpful in differentiating malignancy and benign lesions. A 35-year-old female was found to have a parotid mass for 1 year. Preoperative evaluation including computed tomography and magnetic resonance imaging were non-diagnostic, but, fine needle aspiration cytology on parotid mass showed the suspicion of a low-grade mucoepidermoid carcinoma. Superficial parotidectomy and selective neck node dissection were done based on cytology. However, final pathological examination confirmed benign pleomorphic adenoma. Here, the diagnostic accuracy and cautions in interpretation of result of fine needle aspiration cytology is discussed with respect to the case.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제50권1호
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• pp.41-48
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• 2024

Objectives: Botulinum toxin type A (BTX), a powerful neurotoxin, can be an effective treatment choice for diverse muscular disorders and can reduce abnormal muscle activities. Abnormal movements of the mandible can be caused by involuntary and uncontrolled contractions of the lateral pterygoid muscle (LP) in various pathological situations. Previous reports have shown that BTX can reduce abnormal contractions of the LP. However, needle placement into the LP for BTX injection requires skill, experience, and sufficient anatomical knowledge. To place the needle precisely into the LP, ultrasonography (USG) can be used as an effective needle-guidance modality. USG is a non-invasive imaging modality able to create real-time images without any potential risks, including radiation exposure. Patients and Methods: The patients who had been performed USG-guided BTX injection into the LP using an intraoral approach were included in this study with a literature review and case presentations. Using the USG, four patients received BTX injections to treat recurrent temporomandibular dislocation and oromandibular dystonia resulting from involuntary LP activity. Result: Involuntary movements of the mandible were improved successfully in all patients, and showed satisfactory results without significant complication. Conclusion: The intraoral approach could prevent potential complications during needle placement. USG-guided BTX injection is an effective, convenient, and safe method that provides real-time imaging without unnecessary pain to the patient.

• Investigative Magnetic Resonance Imaging
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• 제23권2호
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• pp.142-147
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• 2019

Piriformis syndrome caused by an accessory belly of the piriformis muscle is very rare. Only a few cases have been reported. Here, we report a case of piriformis syndrome resulting from an extremely rare type of accessory belly of the piriformis muscle originated at the proximal third portion of the main piriformis muscle and attached separately to the greater trochanter inferior to the insertion of the main piriformis muscle. A definitive diagnosis of piriformis syndrome was made based on magnetic resonance imaging and magnetic resonance neurography findings that were consistent with results of nerve conduction study and needle electromyography.

• The Korean Journal of Pain
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• 제25권2호
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• pp.81-88
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• 2012

Background: In discography performed during percutaneous endoscopic lumbar discectomy (PELD) via the posterolateral approach, it is difficult to create a fluoroscopic tunnel view because a long needle is required for discography and the guide-wire used for consecutive PELD interrupts rotation of fluoroscope. A stereotactic system was designed to facilitate the determination of the needle entry point, and the feasibility of this system was evaluated during interventional spine procedures. Methods: A newly designed stereotactic guidance system underwent a field test application for PELD. Sixty patients who underwent single-level PELD at L4-L5 were randomly divided into conventional or stereotactic groups. PELD was performed via the posterolateral approach using the entry point on the skin determined by premeasured distance from the midline and angles according to preoperative magnetic resonance imaging (MRI) findings. Needle entry accuracy provided by the two groups was determined by comparing the distance and angle measured by postoperative computed tomography with those measured by preoperative MRI. The duration and radiation exposure for determining the entry point were measured in the groups. Results: The new stereotactic guidance system and the conventional method provided similarly accurate entry points for discography and consecutive PELD. However, the new stereotactic guidance system lowered the duration and radiation exposure for determining the entry point. Conclusions: The new stereotactic guidance system under fluoroscopy provided a reliable needle entry point for discography and consecutive PELD. Furthermore, it reduced the duration and radiation exposure associated with determining needle entry.