Medical thoracoscopy (MT) /pleuroscopy (P) is a minimally-invasive endoscopic procedure that has become an unavoidable tool for the management of pleural diseases. Offering direct access to the pleural cavity allows pulmonologists to perform diagnostic and therapeutic maneuvers at the same time with efficiency usually shortening the hospitalization duration. A distinction must be made between MT/P done by pulmonologists, which may be video-assisted, and surgical thoracoscopy or video-assisted thoracoscopy surgery (VATS). MT is usually performed by pulmonologists using a non-disposable rigid or semi-rigid telescope in the endoscopy suite under local anesthesia and with intravenous conscious sedation/analgesia or mild anesthesia with a patient in spontaneous breathing. Conversely, VATS usually requires general anesthesia and double-lumen tracheal intubation. MT/P is mainly indicated for diagnostic purposes (pleural effusions) and/or talc pleurodesis ( "poudrage" ) to prevent the recurrence of persistent pleural effusions or pneumothorax. In these cases, one can say that "when a chest tube is required it should take for an interventional pulmonologist a few additional minutes to introduce an endoscope via the same incision, to inspect the pleural cavity, to locate potential adhesions, to obtain pleural samples, to insufflate agent for pleural symphysis and to put the chest tube in adequate position." For these most common indications, MT/P performed by pulmonologists is safe. Prospective studies are nevertheless mandatory to define the place of MT/P, although usually feasible, for the management of pleural infections and pneumothorax. This comprehensive review describes the role of MT/P in assessing pleural diseases providing insights into procedural details, diagnostic performance, safety considerations, and clinical applications. In weighing the advantages and disadvantages of this procedure in comparison to alternative diagnostic and therapeutic modalities, this review aims to show the benefits of MT/P in different scenarios. Finally, a few thoughts about the future directions of this endoscopy procedure are proposed.

Pulse oximetry has become an essential tool in modern respiratory monitoring, enabling noninvasive, real-time measurement of arterial oxygen saturation. This narrative review explores the historical development of pulse oximetry, with a particular focus on two pioneering devices: the OLV-5100, an early commercial prototype developed by Nihon Kohden, and the MET-1471, the world's first fingertip pulse oximeter created by Minolta Camera. These devices played a crucial role in advancing pulse oximetry technology and are now preserved and displayed at Asahikawa Medical University to commemorate their historical significance.

The development of pulse oximetry can be traced back to early optical oximeters, such as the Wood-type ear oximeter, which required tissue compression for calibration. A breakthrough occurred in the 1970s when Takuo Aoyagi discovered that pulsatile arterial blood could serve as a continuous baseline reference, eliminating the need for baseline fixation. His innovation laid the foundation for modern pulse oximetry. Around the same time, Susumu Nakajima conducted the first clinical evaluation of pulse oximeters and contributed to their practical application in medicine. Despite early technical limitations, these pioneering efforts paved the way for subsequent advancements, leading to the widespread adoption of pulse oximeters in critical care and anesthesia.

This review highlights the technological evolution, key contributors, and historical milestones of pulse oximetry, emphasizing Japan's significant role in its development. The preservation of these historical devices at Asahikawa Medical University serves as a tribute to their impact on medical innovation and respiratory care. We also hope that this review will inspire young physicians to take an interest in the development of medical devices.

Chronic obstructive pulmonary disease (COPD) is a common global respiratory condition, that significantly affects patients' quality of life and survival. In recent years, continuous advancements in medical technology have introduced several new bronchoscopy techniques into clinical practice. Bronchoscopy is effective in evaluating airway inflammation and conducting pathological examinations, providing a crucial foundation for the early diagnosis of COPD. It also plays a key role in COPD treatment, including bronchodilation therapy and lung volume reduction surgery. This article reviews current research results and recent progress in bronchoscopy, analyzing its specific applications in COPD.

Background: Dietary supplements are commonly used in Japan. Although some dietary supplements can affect perioperative conditions owing to abnormalities in the blood coagulation system, there are no reports examining the duration of withdrawal and the risk of complications during bronchoscopy. We aimed to retrospectively review the safety and withdrawal periods of supplements before bronchoscopy in patients who regularly consumed dietary supplements.

Materials and Methods: This single-center retrospective observational study was conducted at Tottori University Hospital. Patients who underwent bronchoscopy between January 2019 and December 2019 were validated and examined. We examined patient backgrounds, including consumption of dietary supplements and the type of bronchoscopy procedure. Data regarding the duration of dietary supplement withdrawal and complications during and after bronchoscopy were also collected.

Results: A total of 351 bronchoscopy procedures were performed during the observation period. Of these, 69 bronchoscopies (23.3%) were performed in patients who regularly used dietary supplements. There were 19 cases of invasive bronchoscopy in patients who regularly used dietary supplements with bleeding risk. The median withdrawal period for the dietary supplements was 14 days. The incidence of bleeding complications from invasive bronchoscopy did not differ significantly among the patients who took antithrombotic agents or dietary supplements with bleeding risk.

Conclusions: On the basis of this retrospective analysis, dietary supplements may be considered safe if they are withdrawn at a significant interval (≥7 days) before patients undergo invasive bronchoscopy.

Diffuse large B-cell lymphoma (DLBCL) commonly presents at various anatomical sites. However, primary involvement of the middle mediastinum is rare. We report a 72-year-old male who presented with progressive dyspnea due to severe bronchial obstruction caused by a middle mediastinal mass. Bronchoscopic examination revealed erythematous mucosa with irregular submucosal vessels and white nodules, along with near-complete stenosis of the left main bronchus. Forceps biopsy led to the diagnosis of DLBCL. The patient underwent emergency palliative radiotherapy, which resulted in rapid airway recanalization, followed by successful systemic chemotherapy. This case report provides valuable insights into both the bronchoscopic findings and the therapeutic management of this rare clinical presentation, enhancing our understanding of mediastinal DLBCL with airway involvement.

A 63-year-old man from Okinawa prefecture presented at our hospital with anemia, weight loss, abdominal distension, constipation, and a dry cough. Alveolar hemorrhage developed in the patient during his visits to the hospital. Strongyloides stercoralis was identified in both duodenal specimen and bronchoalveolar lavage fluid, leading to a diagnosis of alveolar hemorrhage due to Strongyloides infection. However, the patient died from respiratory failure and hemorrhagic shock before receiving ivermectin treatment. A postmortem autopsy confirmed disseminated strongyloidiasis, and extensive alveolar hemorrhage and diffuse alveolar damage were found in both lungs, which was the main cause of the death. Contributing factors to the severity of the disease included a human T-cell leukemia virus type 1 (HTLV-1) carrier and malnutrition. Strongyloides stercoralis can autoinfect, and in individuals using immunosuppressants or infected with HTLV-1, hyperinfection and disseminated infection to systemic organs may occur. The mortality rate from disseminated strongyloidiasis was high, underscoring the importance of early diagnosis. Patients who have lived in Okinawa, Amami, or southern Kyushu may experience gastrointestinal symptoms such as constipation and abdominal pain, or acute respiratory failure. Respiratory symptoms such as alveolar hemorrhage could be an early indicator of strongyloidiasis, necessitating thorough examinations and a high index of suspicion for this disease.

Hyperparathyroidism, which is primarily caused by excessive parathyroid hormone secretion, can result in hypercalcemia, urinary tract stones, and osteoporosis. Although most cases involve parathyroid adenomas in the cervical region, ectopic adenomas of the mediastinum are rare. This study reports a 78-year-old woman with hypercalcemia and an ectopic mediastinal parathyroid adenoma diagnosed via chest computed tomography and 99mTc-methoxyisobutylisonitrile (MIBI) scintigraphy. Robot-assisted resection was performed using the da Vinci Xi system. Methylene blue facilitated tumor identification during surgery, and the adenoma was successfully excised without complications. Postoperatively, the calcium and parathyroid hormone levels normalized, and the patient recovered without recurrence.

Ectopic parathyroid adenomas, arising from developmental anomalies, can be challenging to localize and identify; however, imaging techniques such as MIBI and intraoperative methylene blue staining aid in detection. Robot-assisted surgery offers superior visualization and maneuverability compared to traditional methods, especially in confined spaces. It minimizes invasiveness, improves cosmetic outcomes, and reduces recovery time. This case underscores the utility of robotic surgery for the safe and precise removal of ectopic parathyroid adenomas, highlighting its advantages in managing complex mediastinal cases.

A male patient in his 80s was referred to our institution for the evaluation and treatment of a right lung tumor; hence, a diagnostic bronchoscopy was scheduled. His previous physician had prescribed hemostatic agents for nasal bleeding and bloody sputum; however, sudden massive hemoptysis was observed during computed tomography (CT) at our hospital. Approximately a cup of blood was expectorated with rapidly declining oxygen saturation levels. The chest CT scan revealed significant hemorrhage originating from the right middle lobe lung tumor, and an emergency bronchoscopy was performed. Active bleeding from the right middle lobe bronchus was confirmed; hence, endobronchial occlusion was conducted using three silicone spigots resulting in immediate hemostasis. The patient's respiratory and circulatory status was stable, and the lung tumor was strongly suspected to be cT2aN0M0, cStage IB lung cancer; hence, a right middle lobectomy was performed the following day. The postoperative course was uneventful, and the patient was discharged on day 9 postoperatively. Endobronchial occlusion using silicone spigots originally developed for treating persistent air leak pneumothorax, fistulous pyothorax, and bronchopleural fistula, is also useful for managing life-threatening hemorrhage, potentially obviating the necessity for emergency surgery and facilitating safer surgical planning.

Endobronchial ultrasound (EBUS) -guided intranodal forceps biopsy (EBUS-IFB) has gained attention as a complementary procedure to improve the diagnostic yield and tissue acquisition of EBUS-guided transbronchial needle aspiration (EBUS-TBNA) in thoracic lymphadenopathy. Despite the promise of EBUS-IFB, its safety profile remains underreported, with no serious infections documented. We present a case of infectious mediastinitis and pericarditis following EBUS-IFB. A 54-year-old man underwent EBUS-TBNA and EBUS-IFB for the diagnosis of squamous cell carcinoma. Despite prophylactic antibiotics, 25 days after the procedure, the patient developed fever, tachycardia, and hypotension, and was diagnosed with infectious mediastinitis and pericarditis. Pericardial drainage and antibiotic therapy were administered, and the patient recovered after pericardial window surgery. This case highlights the potential for infectious complications with EBUS-IFB, underscoring the need for further investigation into risk factors and optimal procedural techniques for mitigating infection risk. Awareness of these complications is crucial in improving patient outcomes, particularly in high-risk individuals undergoing EBUS procedures.

Chronic pulmonary aspergillosis (CPA) typically presents with imaging findings such as cavities, fungal balls, and thickened cavity walls, with chronic cavitary pulmonary aspergillosis being the most common form. Diagnosing CPA can be challenging when imaging findings appear as a mass. We report a woman in her 70s referred to our hospital for a gradually enlarging abnormal lung shadow. Her medical history included pulmonary tuberculosis at the age of 50 years. Chest computed tomography (CT) revealed a progressively enlarging mass without a cavity, featuring partial calcification and apparent continuity with nodular opacities in the left lower lobe. Contrast-enhanced CT revealed a tumor-like mass with contrast-enhancing septations, having a stone-paved appearance. Bronchoscopy indicated stenosis of the trachea and left main bronchus. A CT-guided lung biopsy was performed, and Aspergillus terreus was identified in the culture of the biopsied specimen, leading to a CPA diagnosis. Voriconazole was administered, causing mass size reduction, as evidenced by follow-up imaging. This report highlights that CPA should be considered in patients with a tumor-like mass with a stone-paved appearance, even without residual cavitation from pulmonary tuberculosis.

Anomalous systemic arterial supply to the normal basal segment is a rare congenital anomaly in which the basal segment of the lung has a normal bronchial pattern but lacks a normal pulmonary artery. Instead, it receives blood supply from the aorta and drains into a normal pulmonary vein. A 75-year-old woman was incidentally found to have a left lower lobe mass on abdominal magnetic resonance imaging. Contrast-enhanced computed tomography (CT) revealed a nodule in left S10 segment along with anomalous systemic arterial supply to the normal basal segment. ¹⁸F- fluorodeoxyglucose positron emission tomography/CT demonstrated fluorodeoxyglucose uptake in the left lower lobe nodule. Bronchoscopy and transbronchial biopsy confirmed the diagnosis of invasive mucinous adenocarcinoma. Since it was not possible to resect the tumor surgically, chemotherapy was initiated. Although the coexistence of primary lung cancer with anomalous systemic arterial supply to the normal basal segment is rare, histopathological diagnosis should be actively considered for masses near the aberrant artery rather than relying solely on imaging findings to ensure timely diagnosis and treatment.

Diffuse aspiration bronchiolitis (DAB) refers to chronic inflammation of the bronchioles caused by repeated microaspiration. It is commonly observed in older individuals with dysphagia or specific underlying diseases. However, few cases have been reported in younger individuals without significant medical history. This report presents the case of a 36-year-old woman with a history of habitual alcohol consumption who developed a persistent cough following episodes of excessive alcohol intake and recurrent vomiting. Chest computed tomography revealed a tree-in-bud appearance and bilateral consolidation of the lower lobes. A transbronchial lung biopsy (TBLB) confirmed the diagnosis of DAB through the identification of foreign-body granulomas. The patient's symptoms improved with alcohol abstinence and lifestyle modifications. This case underscores habitual alcohol consumption as a potential risk factor for DAB in younger individuals and highlights the diagnostic value of TBLB, particularly when surgical lung biopsy is not feasible. Addressing modifiable risk factors is critical for effective management and prevention of recurrent DAB.

Introduction: Surgery is the preferred treatment for bronchial carcinoid, often involving resection of the affected bronchi with or without lobectomy. Proper bronchial transection and anastomosis are critical and require careful, case-by-case planning.

Technical Report: The patient was a 52-year-old woman with intermittent bloody sputum. A chest computed tomography scan revealed a nodule obstructing the bronchus intermedius, while bronchoscopy identified a polypoid tumor near the upper lobar bronchus. The tumor was excised at its narrow base using a high-frequency snare, and pathology confirmed a typical carcinoid diagnosis. Concern about residual tumor at the margin necessitated surgical resection.

Preoperative planning involved creating a three-dimensional-printed bronchial model from computed tomography scan images to simulate sleeve resection. The model revealed a caliber mismatch between the proximal and distal bronchus intermedius after resection. This mismatch was addressed with a telescopic anastomosis technique. During surgery, the planned procedure was replicated, successfully resecting the lesion and achieving satisfactory anastomosis.

Conclusions: A definite diagnosis of a typical carcinoid was obtained via high-frequency snare resection. Moreover, the extent of resection and differences in the caliber of the anastomosis were determined in advance through preoperative simulation with a three-dimensional-printed bronchial model. Sleeve resection of the bronchus intermedius was successfully performed.

Introduction: Flex-rigid pleurovideoscopy for pleural biopsy under local anesthesia is a widespread substitute for thoracoscopic pleural biopsy under general anesthesia. Large, full-thickness pleural specimens are essential for improving diagnostic yield. Cryobiopsy provides a larger specimen with fewer crush artifacts but causes bleeding complications. We developed a novel hemostatic method, called the "cotton swab compression method," using a cotton swab to achieve hemostasis during pleural cryobiopsy.

Technical Report: In this procedure, a single 1.5-cm skin incision is made. After subpleural local anesthesia, the parietal pleura is incised to the endothoracic fascia using an electrocautery inserted in the same port with a pleurovideoscope. A cotton swab is inserted with the pleurovideoscope. The cryoprobe is attached to the lateral side of the incised pleura, and cryobiopsy is performed. After 6-12 seconds of freezing, the scope and cryoprobe are withdrawn slowly while observing the biopsy site. Observed bleeding is managed by compression of the biopsy site using a cotton swab. The specimen is collected while any ongoing bleeding is controlled by astriction.

Conclusions: This novel method allows for the safe collection of larger specimens with longer freezing times while only requiring cotton swabs, making it a simple and effective pleural cryobiopsy technique.