Postoperative cerebral air embolism with delayed abnormal brain MRI findings

Cerebral air embolism (CAE) is a rare but well-known complication resulting from invasive medical procedures; however, previous studies have not examined the postoperative longitudinal MRI changes in CAE. In particular, the likelihood that such changes may be observed after an initial delay when using magnetic resonance imaging (MRI) has not been explored. We herein report a case of CAE with no MRI abnormalities 4 h after a pulmonary vein isolation (PVI) procedure and where the first abnormality was found 22 h after the procedure. A 65-year-old man underwent PVI for paroxysmal atrial fibrillation and showed no signs of recovery from anesthesia after the procedure; thus, he was transferred to our emergency department for further examination. Neurological examination revealed conjugate eye deviation to the right and quadriplegia. Although initial computed tomography (CT) and MRI revealed no abnormalities, CAE was suspected, and a high-concentration oxygen treatment was administered. MRI performed 22 h after the procedure revealed restricted diffusion affecting the cortical areas. At the same day, he was transferred for hyperbaric‑oxygen chamber treatment. After 7 days of treatment, the patient recovered clinically and neurologically. He regained consciousness and was able to communicate. As suggested by this case, CT and MRI findings may fail to reveal CAE abnormalities initially. In such cases, as urgent treatment is necessary, it is important to consider diagnosing CAE based on the patient's history and administering a high concentration of oxygen. Finally, to reach a correct diagnosis, repeated brain MRI should be considered for patients with suspected CAE.

rRT-PCR Results of a Covid-19 Diagnosed Geriatric Patient

In this study, we aimed to present a geriatric patient with the diagnosis of COVID-19 and with contradictory results in rRT-PCR examinations in short time intervals. A 69-year-old male patient was admitted to the emergency room on the 18th day of May 2020, with the complaints of fever, sweating, myalgia, dry cough that continued for 5 days, and the lack of taste that started on the day he applied to the emergency room. Comorbidity factors include diabetes mellitus, bronchial asthma, and hypertension. The patient has a history of 36 years of smoking 1.5 packs per day. High laboratory findings during hospitalization: monocytes, creatinine, CRP (C-reactive protein). In the thorax CT, in the parenchyma areas of both lungs, there are increases in attenuation with multilobe distributions (more visible at the level of the upper lobes) in the form of ground-glass opacities. May 19, 2020, was subjected to the rRT-PCR test, repeated twice on the 19th of May which also resulted in positive. Despite rRT-PCR tests, which were negative on 27th of May and positive on 28th of May, the patient, whose symptoms disappeared, and general condition improved, was discharged on June 1, 2020, with the recommendation for home isolation. In our case, unlike the incubation period only, we encountered a negative rRT-PCR result on the 8th day after diagnosis. Therefore, the COVID-19 pandemic control and filiation evaluation with the rRT-PCR test may produce false negative results.

Is the frozen section examination for sentinel lymph node necessary in early breast cancer patients?

Purpose

Sentinel lymph node (SLN) biopsy (SLNB) is widely performed for axillary staging in patients with breast cancer. Based on the results of frozen section examination (FSE), surgeons can decide to continue further axillary dissections. This study aimed to verify the accuracy of FSE for SLNs.

Methods

We reviewed the records of 4,219 patients who underwent SLNB for primary invasive breast cancer between 2007 and 2016 at the Severance Hospital. We evaluated factors associated with the false-negative results of FSE for SLNs using the Generalized Estimating Equations model.

Results

A total of 1,397 SLNs from 908 patients were confirmed to be metastatic. Seventy-one patients (1.7%) had confirmed pathologic N2 or N3 stage. Among metastatic SLNs, micrometastasis was found in 234 (16.8%). The overall accuracy of SLNB was 98.5%. The sensitivity and false-negative rate of FSE were 86.4% and 13.6%, respectively. Several clinicopathological factors, including the size of SLN metastases, suspicious preoperative axillary lymph nodes, and luminal B subtype, were associated with a higher rate of false-negative results.

Conclusion

Most patients were not indicated for axillary lymph node dissection. Some patients may show transition in their permanent pathology due to the size of the metastatic node. However, the false-negative results of FSE for SLNs based on the size of the metastatic node did not change our practice. Therefore, intraoperative FSE for SLN should not be routinely performed for all breast cancer patients.