On the redshift distribution and physical properties of ACT-selected DSFGs.

We present multi-wavelength detections of nine candidate gravitationally-lensed dusty star-forming galaxies (DSFGs) selected at 218GHz (1.4mm) from the ACT equatorial survey. Among the brightest ACT sources, these represent the subset of the total ACT sample lying in Herschel SPIRE fields, and all nine of the 218GHz detections were found to have bright Herschel counterparts. By fitting their spectral energy distributions (SEDs) with a modified blackbody model with power-law temperature distribution, we find the sample has a median redshift of z = 4.1 - 1.0 + 1.1 (68 per cent confidence interval), as expected for 218GHz selection, and an apparent total infrared luminosity of log 10 ( µ L IR / L ⊙ ) = 13.86 - 0.30 + 0.33 , which suggests that they are either strongly lensed sources or unresolved collections of unlensed DSFGs. The effective apparent diameter of the sample is µ d = 4.2 - 1.0 + 1.7 kpc , further evidence of strong lensing or multiplicity, since the typical diameter of dusty star-forming galaxies is 1.0-2.5 kpc. We emphasize that the effective apparent diameter derives from SED modelling without the assumption of optically thin dust (as opposed to image morphology). We find that the sources have substantial optical depth. ( τ = 4.2 - 1.9 + 3.7 ) to dust around the peak in the modified blackbody spectrum (λ obs ⩽ 500µm), a result that is robust to model choice.

Joint analysis of BICEP2/keck array and Planck Data.

We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400 deg^{2} patch of sky centered on RA 0 h, Dec. -57.5°. The combined maps reach a depth of 57 nK deg in Stokes Q and U in a band centered at 150 GHz. Planck has observed the full sky in polarization at seven frequencies from 30 to 353 GHz, but much less deeply in any given region (1.2 µK deg in Q and U at 143 GHz). We detect 150×353 cross-correlation in B modes at high significance. We fit the single- and cross-frequency power spectra at frequencies ≥150 GHz to a lensed-ΛCDM model that includes dust and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r), using a prior on the frequency spectral behavior of polarized dust emission from previous Planck analysis of other regions of the sky. We find strong evidence for dust and no statistically significant evidence for tensor modes. We probe various model variations and extensions, including adding a synchrotron component in combination with lower frequency data, and find that these make little difference to the r constraint. Finally, we present an alternative analysis which is similar to a map-based cleaning of the dust contribution, and show that this gives similar constraints. The final result is expressed as a likelihood curve for r, and yields an upper limit r_{0.05}<0.12 at 95% confidence. Marginalizing over dust and r, lensing B modes are detected at 7.0σ significance.

Polarization observations with the Cosmic Background Imager.

Polarization observations of the cosmic microwave background with the Cosmic Background Imager from September 2002 to May 2004 provide a significant detection of the E-mode polarization and reveal an angular power spectrum of polarized emission showing peaks and valleys that are shifted in phase by half a cycle relative to those of the total intensity spectrum. This key agreement between the phase of the observed polarization spectrum and that predicted on the basis of the total intensity spectrum provides support for the standard model of cosmology, in which dark matter and dark energy are the dominant constituents, the geometry is close to flat, and primordial density fluctuations are predominantly adiabatic with a matter power spectrum commensurate with inflationary cosmological models.

Treatment of aneurysmal bone cysts of the pelvis and sacrum.

BACKGROUND: Aneurysmal bone cysts are benign, non-neoplastic, highly vascular bone lesions. The purpose of this study was to describe the prevalence, the clinical presentation, and the recurrence rate of aneurysmal bone cysts of the pelvis and sacrum and to examine the diagnostic and therapeutic options and prognosis for patients with this condition. METHODS: Forty consecutive patients with an aneurysmal bone cyst of the pelvis and/or sacrum were treated from 1921 to 1996. Their medical records and radiographic and imaging studies were reviewed, and histological sections from the cysts were examined. Seventeen lesions were iliosacral, sixteen were acetabular, and seven were ischiopubic. Seven involved the hip joint, and two involved the sacroiliac joint. All twelve sacral lesions extended to more than one sacral segment and were associated with neurological signs and symptoms. Destructive acetabular lesions were associated with pathological fracture in five patients and with medial migration of the femoral head, hip subluxation, and hip dislocation in one patient each. The mean duration of follow-up was thirteen years (range, three to fifty-three years). RESULTS: Thirty-five patients who were initially treated for a primary lesion had surgical treatment (twenty-one had excision-curettage and fourteen had intralesional excision); two patients also had adjuvant radiation therapy. Of the thirty-five patients, five (14%) had a local recurrence noted less than eighteen months after the operation. Of five patients initially treated for a recurrent lesion, one had a local recurrence. At the latest follow-up examination, all forty patients were disease-free and twenty-eight (70%) were asymptomatic. There were two deep infections. CONCLUSION: Aneurysmal bone cysts of the pelvis and sacrum are usually aggressive lesions associated with substantial bone destruction, pathological fractures, and local recurrence. Current management recommendations include preoperative selective arterial embolization, excision-curettage, and bone-grafting.

Cosmology from MAXIMA-1, BOOMERANG, and COBE DMR cosmic microwave background observations.

Recent results from BOOMERANG-98 and MAXIMA-1, taken together with COBE DMR, provide consistent and high signal-to-noise measurements of the cosmic microwave background power spectrum at spherical harmonic multipole bands over 2

Aneurysmal bone cyst of the spine. Management and outcome.

STUDY DESIGN: The clinical records, radiographs, histologic sections, and operative reports of 52 consecutive patients with an aneurysmal bone cyst of the spine were reviewed to evaluate diagnostic and therapeutic options and to correlate treatment and outcome. OBJECTIVES: To define the incidence, clinical presentation, diagnostic and therapeutic options, and prognosis of patients with aneurysmal bone cyst of the spine. SUMMARY OF BACKGROUND DATA: There are special considerations in the management of spinal lesions: relative inaccessibility of the lesions, associated intraoperative bleeding, necessity of removing the entire lesion to avoid the possibility of recurrence, proximity of the lesion to the spinal cord and nerve roots, and potential postoperative bony spinal instability. METHODS: Fifty-two consecutive patients with an aneurysmal bone cyst of the spine were treated from 1910 to 1993. Forty patients initially treated for a primary lesion had operative treatment (19 intralesional excision and bone grafting and 21 intralesional excision); four also had adjuvant radiation therapy. Preoperative arterial embolization was performed in two. RESULTS: There was a recurrence rate of 10% within 10 years. All recurrences were noted less than 6 months after surgery. Of 12 patients treated for a recurrent lesion, two had a subsequent recurrence (16.7%) within 9 years. At last follow-up examination, 50 patients (96%) were free of the disease. One patient died of postradiation osteosarcoma, and one died of intraoperative bleeding. CONCLUSION: Current treatment recommendations involve preoperative selective arterial embolization, intralesional excision curettage, bone grafting, and fusion of the affected area if instability is present.

Cosmic microwave background theory.

A long-standing goal of theorists has been to constrain cosmological parameters that define the structure formation theory from cosmic microwave background (CMB) anisotropy experiments and large-scale structure (LSS) observations. The status and future promise of this enterprise is described. Current band-powers in -space are consistent with a DeltaT flat in frequency and broadly follow inflation-based expectations. That the levels are approximately (10(-5))2 provides strong support for the gravitational instability theory, while the Far Infrared Absolute Spectrophotometer (FIRAS) constraints on energy injection rule out cosmic explosions as a dominant source of LSS. Band-powers at 100 suggest that the universe could not have re-ionized too early. To get the LSS of Cosmic Background Explorer (COBE)-normalized fluctuations right provides encouraging support that the initial fluctuation spectrum was not far off the scale invariant form that inflation models prefer: e.g., for tilted Lambda cold dark matter sequences of fixed 13-Gyr age (with the Hubble constant H0 marginalized), ns = 1.17 +/- 0.3 for Differential Microwave Radiometer (DMR) only; 1.15 +/- 0.08 for DMR plus the SK95 experiment; 1.00 +/- 0.04 for DMR plus all smaller angle experiments; 1.00 +/- 0.05 when LSS constraints are included as well. The CMB alone currently gives weak constraints on Lambda and moderate constraints on Omegatot, but theoretical forecasts of future long duration balloon and satellite experiments are shown which predict percent-level accuracy among a large fraction of the 10+ parameters characterizing the cosmic structure formation theory, at least if it is an inflation variant.

Assessment of the ratio of carpal contents to carpal tunnel volume in patients with carpal tunnel syndrome: a preliminary report.

An anatomic basis for carpal tunnel syndrome (CTS) has been proposed but not confirmed; both volumetric and area studies have been used to address this issue. The authors have demonstrated that the ratio of the carpal tunnel contents (CTC) to carpal tunnel volume (CTV) provides information regarding the relative free space in the carpal tunnel as compared with canal volume alone. This study was undertaken to determine whether the CTC/CTV ratio was higher for patients with CTS than for normal subjects. Seven asymptomatic volunteers and 7 patients with symptoms of CTS underwent magnetic resonance imaging (MRI) so that the CTC/CTV ratios could be determined. Standard radiographs were analyzed to identify plain radiographic variables that differed between patients with CTS and control subjects, and no differences were found. On MRIs, however, CTC/CTV ratios were noted to be higher for patients with CTS than for matched control subjects.

Small cell osteosarcoma of bone. Review of 72 cases.

BACKGROUND: Small cell osteosarcoma of bone is a rare form of osteosarcoma, with an incidence rate of 1.3%. This tumor must be differentiated from other small cell malignancies because of treatment considerations, particularly patient response to chemotherapy. METHODS: Clinicopathologic findings in 72 cases (22 from Mayo Clinic files and 50 from consultation files) of small cell osteosarcoma of bone were studied. RESULTS: The femur was the most common bone involved, although the tumor was found in all portions of the skeleton. Radiographic features (available in 35 cases) suggested a diagnosis of osteosarcoma in 20 cases, Ewing's sarcoma or lymphoma in 14 cases, and giant cell tumor in 1 case. Histologically, there were four types according to the predominant cell size and cytologic features. Osteoid production was identified in all tumors. Complete treatment and follow-up data were available for 45 cases. Generally, in those cases without surgical treatment, greater than 60% of patients died of disease within 2 years. If the surgical procedure was associated with a marginal tumor margin, the prognosis was poor. In the 30 patients with wide or radical surgical margins, at last follow-up 13 were alive with no evidence of disease, 2 were alive with disease, and 15 died of disease at 5 months to 13.1 years after diagnosis. In 16 of 22 Mayo Clinic patients, excluding those who presented with metastasis, the cumulative 5-year survival rate was 28.9%. Median survival time in patients who had surgery with additional chemotherapy was 13.4 years, compared with 1.4 years in patients who underwent surgery alone (P = 0.17). CONCLUSIONS: Small cell osteosarcoma is a definite reproducible histologic entity. Treatment should be based on a protocol for osteosarcoma.

Screen-film versus computed radiography imaging of the hand: a direct comparison.

OBJECTIVE: Computed radiography of the musculoskeletal system has the potential to become a powerful tool in the practice of diagnostic radiology. It addresses many of the geographic and film-distribution concerns facing diagnostic imaging. We undertook this study to compare and document the quality of computed radiographs and conventional screen-film images before widespread implementation. MATERIALS AND METHODS: We evaluated clinical images using direct comparison. Bilateral hand images from 50 patients were scored independently by six musculoskeletal radiologists. In each case one hand was imaged with a conventional screen-film technique and the other with computed radiography. Images were masked to eliminate as much bias as possible. The numeric scores assigned to the images by the observers were analyzed using Student's t test. RESULTS: Computed radiographs were judged with statistical significance to be better than conventional screen-film images in all features judged by the observers, including bone cortex, bone trabeculae, corticomedullary junction, distal phalangeal tuft, soft tissues, fat planes, bone-soft-tissue interface, and overall contrast and density. CONCLUSION: The statistically significant determination that the image quality of computed radiographs is at least as good as screen-film images allows confident use of computed radiography and enables radiologists to take advantage of its many other practical capabilities related to image distribution, storage, cost, and geographic coverage without sacrificing image quality.

Malignancies in fibrous dysplasia.

BACKGROUND: Malignancies in fibrous dysplasia are rare. Most cases have been published as single case reports. The role of radiation therapy in the occurrence of sarcoma in fibrous dysplasia is still controversial. METHODS: The Mayo Clinic files were reviewed, including Mayo Clinic cases and consultation cases, to collect all cases of sarcomas arising in fibrous dysplasia. RESULTS: Among 1122 cases with a histologic diagnosis of fibrous dysplasia, 28 cases of sarcoma were found. These 28 cases included 16 Mayo Clinic cases and 12 consultation cases. The sarcomas occurred in 19 cases of monostotic fibrous dysplasia and 9 cases of polyostotic disease (only 1 of Albright's syndrome). The most common histotype was osteosarcoma (19 cases), followed by fibrosarcoma (5 cases), chondrosarcoma (3 cases), and malignant fibrohistiocytoma (1 case). Of the 28 patients, 13 (46%) had received radiation therapy before the sarcoma developed. Most of these sarcomas occurred in the craniofacial bones (13 cases) or in the proximal femur (7 cases), followed by the humerus, pelvis, tibia, and scapula. CONCLUSIONS: Prognosis was poor. Sarcomas may arise with or without radiation. Early diagnosis and adequate treatment may lead to improved prognosis.

Parosteal osteosarcoma. A clinicopathological study.

The records of 226 patients (sixty-seven who were managed at our institution and 159 who were identified from the consultation files) who had had a parosteal osteosarcoma were reviewed. The criteria for diagnosis were that, roentgenographically, the lesion had arisen from the surface of the bone and that, histologically, the tumor was well differentiated (Grade 1 or 2); it was characterized by well formed osteoid within a spindle-cell stroma; and, when there was medullary involvement, less than 25 per cent of the medullary cavity was affected. Dedifferentiation was more common (16 per cent of the patients) than previously reported and was associated with a poor prognosis. Cross-sectional imaging studies demonstrated medullary involvement in 22 per cent of the patients, an unmineralized soft-tissue mass peripheral to the mineral component in 51 per cent, and adjacent soft-tissue invasion in 46 per cent. In contrast to the findings in our previous studies, medullary involvement was not a poor prognostic factor. At an average of thirteen years (range, two to forty-one years), eleven of the sixty-seven patients who were managed at our institution died of the tumor; ten of these patients had a dedifferentiated tumor. Statistical analysis of the thirty-nine patients who had had the primary treatment at our institution revealed that incomplete resection was associated with an increased risk of local recurrence and that dedifferentiation markedly increased the risk of metastasis.

Aneurysmal bone cyst. A clinicopathologic study of 238 cases.

Aneurysmal bone cyst (ABC) is a nonneoplastic expansile bone lesion that mainly affects children and young adults. Primary ABC is relatively rare, with an incidence one half that of giant cell tumor of bone. In 238 patients with ABC studied in the Mayo Clinic files, more than 80% of the lesions were in long bones, flat bones, or the spinal column. Of the lesions initially treated at the Mayo Clinic, 95% were typical ABC; the rest were "solid" variants. Except for the absence of obvious cavernous channels and spaces, there was no significant histologic difference between solid variant and typical ABC. Radiographically, ABC is an eccentric expansile lesion commonly located at the metaphysis of long bones. Computed tomography and magnetic resonance imaging may show multiple internal septations or fluid levels. In the 153 patients treated, 19% had recurrence after curettage (intralesional excision). Recurrence was most common during the first 2 postoperative years.

Radiologic evaluation of hand and wrist motion.

Abnormal motion due to instability at the carpus and distal radioulnar joint can be difficult to diagnose clinically, and radiologic evaluation can be very helpful. The anatomy and kinematics are complex, and a directed approach is necessary to detect the findings that may be subtle and transient. Plain radiographic evaluation of the distal radioulnar joint is very sensitive to slight variations in patient position, and CT is more accurate when pain or cast immobilization make positioning difficult or when there is associated distal radial deformity. Static carpal instability patterns are present on routine radiographs where examination of the lateral view provides the key to diagnosis. The relations between the longitudinal axes of the radius, lunate, capitate, and scaphoid form the basis for classification of these instabilities. In dynamic carpal instability, routine radiographs are normal. The instability is demonstrated only with positional change or manipulation. Motion views can be very helpful, although direct observation of wrist motion on videotape fluoroscopy is the key to the diagnosis of dynamic instability. MR imaging motion studies provide better soft tissue definition and may show subtle changes in the triangular-fibrocartilage-associated distal radioulnar instability, as well as periarticular tendon subluxation about the wrist. The clinical role of MR imaging in the evaluation of wrist motion has yet to be clearly defined.

Takayasu's arteritis. Carotid duplex sonographic appearance, including color Doppler imaging.

Takayasu's arteritis (also known as pulseless disease, aortoarteritis, and aortic arch syndrome) is a chronic inflammatory arteriopathy that affects the aorta and its main branches as well as the pulmonary arteries. We report the carotid duplex sonographic findings of Takayasu's arteritis in three patients. Takayasu's arteritis can be suspected by noting a long segment of diffuse, homogeneous, circumferential vessel wall thickening in the proximal common carotid artery, resulting in narrowing of the lumen. The internal and external carotid arteries are normal.