A New Frontier in Temporal Bone Imaging: Photon-Counting Detector CT Demonstrates Superior Visualization of Critical Anatomic Structures at Reduced Radiation Dose.

BACKGROUND AND PURPOSE: Photon-counting detector CT is a new technology with a limiting spatial resolution of ≤150 µm. In vivo comparisons between photon-counting detector CT and conventional energy-integrating detector CT are needed to determine the clinical impact of photon counting-detector CT in temporal bone imaging. MATERIALS AND METHODS: Prospectively recruited patients underwent temporal bone CT examinations on an investigational photon-counting detector CT system after clinically indicated temporal bone energy-integrating detector CT. Photon-counting detector CT images were obtained at an average 31% lower dose compared with those obtained on the energy-integrating detector CT scanner. Reconstructed images were evaluated in axial, coronal, and Pöschl planes using the smallest available section thickness on each system (0.4 mm on energy-integrating detector CT; 0.2 mm on photon-counting detector CT). Two blinded neuroradiologists compared images side-by-side and scored them using a 5-point Likert scale. A post hoc reassignment of readers' scores was performed so that the scores reflected photon-counting detector CT performance relative to energy-integrating detector CT. RESULTS: Thirteen patients were enrolled, resulting in 26 image sets (left and right sides). The average patient age was 63.6 [SD, 13.4] years; 7 were women. Images from the photon-counting detector CT scanner were significantly preferred by the readers in all reconstructed planes (P < .001). Photon-counting detector CT was rated superior for the evaluation of all individual anatomic structures, with the oval window (4.79) and incudostapedial joint (4.75) receiving the highest scores on a Likert scale of 1-5. CONCLUSIONS: Temporal bone CT images obtained on a photon-counting detector CT scanner were rated as having superior spatial resolution and better critical structure visualization than those obtained on a conventional energy-integrating detector scanner, even with a substantial dose reduction.

Secular trends in opportunistic infections, cancers and mortality in patients with AIDS during the era of modern combination antiretroviral therapy.

OBJECTIVES: The aim of the study was to estimate the incidence of, determine risk factors for, and investigate the consequences of opportunistic infections (OIs) and malignancies among patients with the acquired immune deficiency syndrome (AIDS) in the era of modern combination antiretroviral therapy (cART). METHODS: Three enrolment periods (1998-2002, 2003-2005 and 2006-2012), corresponding to changes in predominant cART regimens, were compared among 1889 participants enrolled in a prospective cohort study, the Longitudinal Study of Ocular Complications of AIDS (LSOCA). Incidences of AIDS-related OIs and cancers were estimated. Multivariate logistic and Cox regression models were used to determine the effect of demographic and clinical characteristics on OIs and mortality. RESULTS: Between participants enrolled in the 1998-2002 and 2006-2012 enrolment periods, the incidence of OIs decreased from 27 per 1000 person-years (PY) to 11 per 1000 PY (P < 0.001), and mortality decreased from 41 per 1000 PY to 18 per 1000 PY (P < 0.0001), corresponding to improvements in cART regimens. CONCLUSIONS: Improvements in cART regimens led to a progressive decline in the incidence of OIs and mortality between 1999 and 2013 among patients with AIDS in the era of modern cART.

Factors affecting attrition in a longitudinal study of patients with AIDS.

Anecdotal data have suggested that retention of HIV-infected patients with immune recovery in longitudinal studies may be difficult as they resume normal activities. This study evaluated risk factors for attrition among patients with AIDS in a cohort study in the era of highly active antiretroviral therapy. Patients with AIDS enrolled in the Longitudinal Study of Ocular Complications of AIDS were evaluated every three months with demographic, clinical and laboratory data collected. Lost to follow-up was defined as any patient who missed all study visits and could not be contacted for 12 consecutive months, who had not died and who did not re-enter the study at a later date. Of the 1,052 patients studied, 77 (7.3%) were lost to follow-up (rate = 0.03/person year). In the multivariate analysis, factors associated with attrition were CD4+ T-cell count category (hazard ratio (HR) = 2.03; 95%CI: 1.01, 4.24; P = 0.05 for CD4+ count < or = 50 cells/microL and HR = 1.96; 95%CI: 1.12, 3.40; P = 0.02 for CD4+ count 51-200 cells/microL) and detectable HIV viral load (HR = 1.29; 95%CI: 1.07, 1.53; P < 0.001 for HIV viral load >400 copies/mL). These data suggest that patients with compromised immunologic status are at an increased risk for being lost to follow-up.

Ocular manifestations of vasculitis.

Systemic necrotizing vasculitis is characterized by inflammation of blood vessels and often affects the eyes. Ocular manifestations of vasculitis may involve any part of the eye or orbit. The frequency of ocular involvement generally is dependent on the size and type of blood vessels affected by the vasculitis. This article reviews the major types of ocular inflammation and then addresses the ocular manifestations of specific systemic vasculitides.

Choroidal white lesions as an early manifestation of sarcoidosis.

PURPOSE: To describe the natural history of a series of patients with fine white choroidal lesions and uveitis of previously unknown cause. METHODS: A retrospective chart review of 11 patients with chronic uveitis and multiple, small (50-100 microm), peripheral white lesions of the choroid was performed using a standardized questionnaire form. RESULTS: Ten of 11 patients were white women with an average age of 62 years. Seven of 11 patients had panuveitis; 4 of 11 patients had vitritis; and 6 of 11 patients had cystoid macular edema. Choroidal white lesions were bilateral in all but one patient. Seven of 11 patients were followed up for more than 1 year. During a 12- to 173-month follow-up (mean, 94 months), these patients showed coalescence and atrophy of the white lesions. Initial systemic examination for the cause of the uveitis and white choroidal lesions was negative in all seven patients. With long-term follow-up, sarcoidosis was diagnosed in five of the seven patients followed for more than 1 year. CONCLUSIONS: The pattern of inflammatory white choroidal lesions distributed in the peripheral retina that atrophy and coalesce with time and that are associated with uveitis in middle-aged white women may represent an early form of sarcoidosis.

Magnetic resonance imaging of acquired Brown syndrome in a patient with psoriasis.

PURPOSE: To report the occurrence of acquired Brown syndrome and associated magnetic resonance imaging findings in a patient with psoriasis. METHODS: A 42-year-old woman with a history of psoriasis developed pain, double vision, and limited elevation of her left eye in adduction. An orbital magnetic resonance image with gadolinium enhancement was obtained. RESULTS: Orbital magnetic resonance image disclosed abnormal enhancement of the left trochlea/tendon complex. The patient's symptoms resolved with corticosteroid therapy. CONCLUSIONS: Acquired Brown syndrome may be associated with psoriasis. The inflammation of the trochlea/tendon complex that can cause acquired Brown syndrome can be demonstrated on magnetic resonance image.

Catheter complications in AIDS patients treated for cytomegalovirus retinitis.

PURPOSE: To describe the complications of central venous catheter use for intravenous therapy of cytomegalovirus (CMV) retinitis in patients with AIDS. METHODS: Retrospective review of 388 patients with AIDS and CMV retinitis treated with intravenous medications through an indwelling catheter. RESULTS: The catheter complication rate was 1.2 complications per person-year (0.33 complications per 100 catheter-days). Current injecting drug use increased the risk of infectious complications [hazard ratio (HR), 1.73; P=0.04] whereas former use did not (HR, 0.96; P=0.88). Subdermal port catheters increased the risk of bacteremia (HR, 1.78; P=0.05). Mortality for the first complication was 5.8%. Forty percent of patients required catheter removal, and 86.8% of these patients required reinsertion of another catheter. CONCLUSIONS: Catheter complications are a substantial problem in patients with CMV retinitis treated with daily intravenous therapy.