Imaging
Those who care for patients with pulmonary, critical care or sleep disorders rely heavily on chest radiology and pathology to determine diagnoses. The Southwest Journal of Pulmonary, Critical Care & Sleep publishes case-based articles with characteristic chest imaging and related pathology.
The editor of this section will oversee and coordinate the publication of a core of the most important chest imaging topics. In doing so, they encourage the submission of unsolicited manuscripts. It cannot be overemphasized that both radiologic and pathologic images must be of excellent quality. As a rule, 600 DPI is sufficient for radiographic and pathologic images. Taking pictures of plain chest radiographs and CT scans with a digital camera is strongly discouraged. The figures should be cited in the text and numbered consecutively. The stain used for pathology specimens and magnification should be mentioned in the figure legend. Those who care for patients with pulmonary, critical care or sleep disorders rely heavily on chest radiology and pathology to determine diagnoses. The Southwest Journal of Pulmonary, Critical Care & Sleep publishes case-based articles with characteristic chest imaging and related pathology. The editor of this section will oversee and coordinate the publication of a core of the most important chest imaging topics. In doing so, they encourage the submission of unsolicited manuscripts. It cannot be overemphasized that both radiologic and pathologic images must be of excellent quality. As a rule, 600 DPI is sufficient for radiographic and pathologic images. Taking pictures of plain chest radiographs and CT scans with a digital camera is strongly discouraged. The figures should be cited in the text and numbered consecutively. The stain used for pathology specimens and magnification should be mentioned in the figure legend.
Medical Image of the Week: PSG Sweat Artifact
Figure 1. A 30 second epoch suggestive of sweat artifact and incidentally noted snore artifact on the M1 channels.
Figure 2: Sweat artifact as seen in a 10 second epoch.
Figure 3. 30 second epoch after removal of the M1 channels.
A 61-year-old man, with a past medical history significant for hypertension, COPD and morbid obesity with a body mass index (BMI) of 45.81 is referred for an overnight sleep study for suspicion of obstructive sleep apnea. Artifact was noted on the polysomnogram recording as shown above (Figures 1-3).
Sweat artifact is characterized by slow undulating movement of the baseline recording in the affected channels due to perspiration altering the potential of the involved electrodes (1). Sweat artifact may mimic delta waves and scored as non-rapid eye movement (NREM) stage 3 sleep. Lowering the room temperature, using a fan on the scalp or replacing the conductive paste on the electrodes may help eliminate the artifact.
Safal Shetty, MD1 and John Roehrs, MD2
1Banner University Medical Center Tucson, AZ
2Southern Arizona VA Health Care System
Tucson, AZ
Reference
- Siddiqui F, Osuna E, Walters AS, Chokroverty S. Sweat artifact and respiratory artifact occurring simultaneously in polysomnogram. Sleep Med. 2006;7(2):197-9. [CrossRef] [PubMed]
Cite as: Shetty S, Roehrs J. Medical image of the week: PSG sweat artifact. Southwest J Pulm Crit Care. 2015;11(4):171-2. doi: http://dx.doi.org/10.13175/swjpcc097-15 PDF
Medical Image of the Week: DBS Polysomnogram Artifact
Safal Shetty, MD
Kenneth S. Knox, MD
Pulmonary, Allergy, Critical Care & Sleep Medicine
Banner University Medical Center
Tucson, AZ
Figure 1. Thirty second epoch showing DBS artifact obscuring all recording channels except flow, efforts belts and the EKG channels.
Figure 2. Ten second epoch showing the electrical artifact due to DBS.
A 79-year-old man with known Parkinson’s disease and status post deep brain stimulator (DBS) implantation underwent an overnight polysomnogram for clinical suspicion of obstructive sleep apnea. Artifact was seen on the polysomnogram recording (Figures 1 & 2).
Patient-related electrical artifacts may be seen from devices such as pacemakers, deep brain stimulators and vagal nerve simulators. Abrupt discontinuation of DBS is associated with a high likelihood of worsening of symptoms in patients with Parkinson’s disease (1). Patients with DBS are most commonly programmed in monopolar mode. Bipolar configuration, forms a short electrical dipole that affects a relatively smaller volume of tissue and generates far less artifact, suggesting that this may be an effective option in a Parkinsonian patient with indications for polysomnography (2).
References
- Chou KL, Siderowf AD, Jaggi JL, Liang GS, Baltuch GH. Unilateral battery depletion in Parkinson's disease patients treated with bilateral subthalamic nucleus deep brain stimulation may require urgent surgical replacement. Stereotact Funct Neurosurg. 2004;82(4):153-5. [CrossRef] [PubMed]
- Frysinger RC, Quigg M, Elias WJ. Bipolar deep brain stimulation permits routine EKG, EEG, and polysomnography. Neurology. 2006;66(2):268-70. [CrossRef] [PubMed]
Cite as: Shetty S, Knox KS. Medical image of the week: DBS polysomnogram artifact. Southwest J Pulm Crit Care. 2015;11(4):151-2. doi: http://dx.doi.org/10.13175/swjpcc096-15 PDF
Medical Image of the Week: Polysomnogram Artifact
Figure 1. Thirty second polysomnogram epoch showing artifact in lead O1M2 (black arrow).
Figure 1. Ten second polysomnogram epoch showing artifact in lead O1M2 (black arrow).
A 54 year-old man with a past medical history of attention deficit hyperactivity disorder (ADHD), low back pain, and paroxysmal supraventricular tachycardia presented to the sleep laboratory for evaluation of sleep disordered breathing. Pertinent medications include fluoxetine, ambien, and clonazepam. His Epworth sleepiness score was 18. He had a total sleep time of 12 min. On the night of his sleep study, the patient was restless and repeatedly changed positions in bed.
Figures 1 and 2 show the artifact determined to be lead displacement of O1M2 after the patient shifted in bed, inadvertently removing one of his scalp electrodes. The sine waves are 60 Hz in frequency. Once the problem was identified, the lead was quickly replaced to its proper position.
Jared Bartell1, Safal Shetty, MD1,2, and John D. Roehrs, MD1,2
1University of Arizona Medical Center
2Southern Arizona VA Health Care System
Tucson, AZ
Reference as: Bartell J, Shetty S, Roehrs JD. Medical image of the week: polysomnogram artifact. Southwest J Pulm Crit Care. 2015;10(2):95-6. doi: http://dx.doi.org/10.13175/swjpcc014-15 PDF
Medical Image of the Week: Wide Mediastinum Due to Lung Infiltrates
Figure 1. Panel A: Admission chest x-ray showing an apparent widened mediastinum. Panels B & C: CT scan showing consolidation in the posterior lungs bilaterally. Panel D: Chest x-ray showing resolution of his widened mediastinum with an increase in positive end-expiratory pressure.
The patient is a 65-year-old man patient with a past medical history of poorly controlled hypertension and coronary artery disease who was admitted after a witnessed code arrest. He was found down, and paramedics arrived within 5 minutes and started chest compressions. His initial CXR showed a wide mediastinum (Figure 1A) that was concerning for possible aortic dissection especially with his history of poorly controlled hypertension. Due to his hemodynamic instability a chest CT scan couldn’t be done initially, but the patient underwent a trans-esophageal echo that was negative for aortic dissection.
When the patient became more stable a chest CT scan with contrast was done and showed consolidation of the medial parts of both lungs with 7 bilateral rib fractures (Figure 1 B & C). The impression was either lung contusion from the aggressive chest compression as evidenced by the bilateral 7 rib fractures or aspiration in the dependent parts of the lung. His apparent widened mediastinum resolved with increasing the positive end-expiratory pressure (PEEP) on the ventilator within 48 hours (Figure 1D).
Huthayfa Ateeli MBBS, Laila Abu Zaid MD
Department of Medicine
University of Arizona
Tucson, AZ.
References
- Cohn SM. Pulmonary contusion: review of the clinical entity. J Trauma. 1997;42(5):973-9. [CrossRef] [PubMed]
- Lai CC, Wang CY, Lin HI, Wang JY. Pulmonary contusion associated with chest compressions. Resuscitation. 2010;81(1):133. [CrossRef] [PubMed]
Reference as: Ateeli H, Zaid LA. Medical image of the week: widen mediastinum due to lung infiltrates. Southwest J Pulm Crit Care. 2015;10(2):77-8. doi: http://dx.doi.org/10.13175/swjpcc007-15 PDF