Utility of INR For Prediction of Delayed Intracranial Hemorrhage Among Warfarin Users with Head Injury.

BACKGROUND: Incidence of delayed intracranial hemorrhage (DICH) in patients on warfarin has been controversial. No previous literature has reported the utility of international normalized ratio (INR) in predicting traumatic DICH. OBJECTIVES: Utilizing INR to risk stratify head trauma patients who may be managed without repeat imaging. METHODS: This was a retrospective study at a Level II trauma center. All patients on warfarin with head injuries from March 2014 to December 31, 2017 were included. Each patient underwent an initial head computed tomography scan (HCT) and subsequent repeat HCT 12 h after. Patients presenting > 12 h after head injury received only one HCT. Two blinded neuroradiologists reviewed each case of DICH. Statistical analysis evaluated Glasgow Coma Scale (GCS), Injury Severity Score (ISS), heart rate, systolic blood pressure (SBP), age, and platelet count. RESULTS: There were 395 patients who qualified for the protocol; 238 were female. Average age was 79 years. Seventy-seven percent of patients underwent repeat HCT. Five resulted in DICH (INR 2.6-3.0), three of which might have been present on initial HCT; incidence rate of 0.51-1.27%. One patient required neurosurgical intervention. Among 80 patients with INR < 2, no DICH was identified, resulting in high sensitivity, but with a wide confidence interval; sensitivity of 100% (95% confidence interval [CI] 47.8-100), specificity 21% (95% CI 16.6-28.9). Correlation of factors: ISS (p = 0.039), GCS (p = 0.978), HR (p = 0.601), SBP (p = 0.198), age (p = 0.014), and platelets (p = 0.281). CONCLUSION: No patient with INR < 2 suffered DICH, suggesting that warfarin users presenting with INR < 2 may be managed without repeat HCT. For INR > 2, patients age and injury severity can be used for shared decision-making to discharge home with standard head injury precautions and no repeat HCT.

Injuries of the head from backface deformation of ballistic protective helmets under ballistic impact.

Modern ballistic helmets defeat penetrating bullets by energy transfer from the projectile to the helmet, producing helmet deformation. This deformation may cause severe injuries without completely perforating the helmet, termed "behind armor blunt trauma" (BABT). As helmets become lighter, the likelihood of larger helmet backface deformation under ballistic impact increases. To characterize the potential for BABT, seven postmortem human head/neck specimens wearing a ballistic protective helmet were exposed to nonperforating impact, using a 9 mm, full metal jacket, 124 grain bullet with velocities of 400-460 m/s. An increasing trend of injury severity was observed, ranging from simple linear fractures to combinations of linear and depressed fractures. Overall, the ability to identify skull fractures resulting from BABT can be used in forensic investigations. Our results demonstrate a high risk of skull fracture due to BABT and necessitate the prevention of BABT as a design factor in future generations of protective gear.

Spinal and paraspinal fungal infections associated with contaminated methylprednisolone injections.

BACKGROUND: A nationwide outbreak of fungal infections was traced to injection of Exserohilum-contaminated methylprednisolone. We describe our experience with patients who developed spinal or paraspinal infection after injection of contaminated methylprednisolone. METHODS: Data were assembled from the Michigan Department of Community Health, electronic medical records, and magnetic resonance imaging (MRI) reports. RESULTS: Of 544 patients who received an epidural injection from a contaminated lot of methylprednisolone at a pain clinic in southeastern Michigan, 153 (28%) were diagnosed at our institution with probable or confirmed spinal or paraspinal fungal infection at the injection site. Forty-one patients had both meningitis and spinal or paraspinal infection, and 112 had only spinal or paraspinal infection. Magnetic resonance imaging abnormalities included abscess, phlegmon, arachnoiditis, and osteomyelitis. Surgical debridement in 116 patients revealed epidural phlegmon and epidural abscess most often. Among 26 patients with an abnormal MRI but with no increase or change in chronic pain, 19 (73%) had infection identified at surgery. Fungal infection was confirmed in 78 patients (51%) by finding hyphae in tissues, positive polymerase chain reaction, or culture. Initial therapy was voriconazole plus liposomal amphotericin B in 115 patients (75%) and voriconazole alone in 38 patients (25%). As of January 31, 2014, 20 patients remained on an azole agent. Five patients died of infection. CONCLUSIONS: We report on 153 patients who had spinal or paraspinal fungal infection at the site of epidural injection of contaminated methylprednisolone. One hundred sixteen (76%) underwent operative debridement in addition to treatment with antifungal agents.

Magnetic resonance imaging screening to identify spinal and paraspinal infections associated with injections of contaminated methylprednisolone acetate.

IMPORTANCE: Injection of contaminated methylprednisolone has resulted in an unprecedented nationwide outbreak of Exserohilum rostratum fungal infections, manifested initially as meningitis and/or basilar stroke. Insidious onset of spinal or paraspinal infection at the injection site has been increasingly reported and is occurring months after receipt of injection with the contaminated drug. The clinical findings are often subtle and similar to those that led the patient to undergo the methylprednisolone injection. OBJECTIVE: To determine if patients who had not presented for medical care but who had received contaminated methylprednisolone developed spinal or paraspinal infection at the injection site using contrast-enhanced magnetic resonance imaging (MRI) screening. DESIGN, SETTING, AND PARTICIPANTS: There were 172 patients who had received an injection of contaminated methylprednisolone from a highly contaminated lot (No. 06292012@26) at a pain facility but had not presented for medical care related to adverse effects after the injection. Screening MRI was performed between November 9, 2012, and April 30, 2013. MAIN OUTCOMES AND MEASURES: Number of persons identified with previously undiagnosed spinal or paraspinal infection. RESULTS: Of the 172 patients screened, MRI was abnormal in 36 (21%), showing epidural or paraspinal abscess or phlegmon, arachnoiditis, spinal osteomyelitis or diskitis, or moderate to severe epidural, paraspinal, or intradural enhancement. Of the 115 patients asked about new or worsening back or neck pain, lower extremity weakness, or radiculopathy symptoms, 35 (30%) had at least 1 symptom. Thirty-five of the 36 patients with abnormal MRIs met the Centers for Disease Control and Prevention (CDC) case definition for probable (17 patients) or confirmed (18 patients) fungal spinal or paraspinal infection. All 35 patients were treated with antifungal agents (voriconazole, with or without liposomal amphotericin B), and 24 required surgical debridement. At the time of surgery, 17 of 24 patients (71%), including 5 patients who denied having symptoms, had laboratory evidence of fungal infection. CONCLUSIONS AND RELEVANCE: Among patients who underwent screening MRI to look for infection at the site of injection of contaminated methylprednisolone, 21% had an abnormal MRI, and all but one met CDC criteria for probable or confirmed fungal spinal or paraspinal infection. Screening MRI led to identification of patients who had minimal or no symptoms of spinal or paraspinal infection and allowed early initiation of medical and surgical treatment.

DWI findings of optic nerve ischemia in the setting of central retinal artery occlusion.

A 67-year-old African-American male with untreated hypertension, hyperlipidemia, and diabetes mellitus presented with sudden, staggering, progressive loss of vision in his left eye over the course of 8 days. Ophthalmologic and fluorescein angiography exams confirmed central retinal artery conclusion, but revealed no embolus. Magnetic resonance imaging of the brain serendipitously revealed restricted diffusion within the distal left optic nerve, illustrating a more proximal occlusion, which matched the fluorescein angiographic findings. Extensive workup revealed no embolic source, postulating primary hypertension as the underlying etiology.

Positron emission tomography/computed tomography potential pitfalls and artifacts.

With the recent use of 18-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) for tumor staging and treatment response, it is important to recognize many pitfalls, artifacts, and benign uptakes that are commonly encountered. Normal physiology can explain many regions of increased FDG activity, as well as incidental benign tumors and benign metabolic conditions. Recognition of characterization of benign causes and physiologic variants for FDG uptake are discussed to avoid improper characterization as a malignancy. A basic understanding of PET/computed tomographic physics is also discussed, in relation to attenuation correction artifacts caused by metallic implants and contrast agents in the gastrointestinal tract, as well as artifacts caused in fused images due to patient motion. Also presented is the rationale for expected, benign uptake in various metabolic diseases, as well as pharmacologic methods for decreasing the artifacts caused by metabolic diseases. PET/computed tomographic evaluation of the thyroid, thymus, adrenal adenomas, uterus and ovaries, infection/inflammatory changes, and postradiation/chemotherapy changes are also discussed, with expected normal changes, as well as pitfalls and artifacts.