Threshold values for stress radiographs in unstable knees after total knee arthroplasty.

PURPOSE: The primary aim of this study was to investigate the potential benefit of stress radiographs for diagnosis of unstable total knee arthroplasty (TKA) and to identify clinically relevant cut-off values to differentiate between unstable and stable TKAs. METHODS: Data of 40 patients with 49 cruciate retaining (CR) TKA who underwent stress radiographs as part of the diagnostic algorithm in a painful knee clinic were prospectively collected. Anterior and posterior stress radiographs were done in 90° and 15° flexion, varus-valgus stress radiographs in 0° and 30° knee flexion. Knee laxity was measured in mm and degrees by two independent observers using standardized landmarks. Intra- and inter-observer single measure intraclass correlations were between 0.92 to 1 and 0.89 to 1, respectively. For evaluation and investigation of the potential cut-off values, two groups of patients with and without revision surgery due to instability were compared. Radiographic measures of standardized z values according to the group without revision due to instability were used to calculate average and maximum laxity z-scores. RESULTS: Knees undergoing revision TKA due to instability showed significantly (p < 0.001) lower (KSS) pain/function scores (94 ± 6.3, range 80-100; control group: 112 ± 19.2, range 80-148) and total KSS scores when compared to the control group. The laxity values of patients with instability were significantly higher in terms of mean values (p < 0.01) when compared to the control group. The maximum laxity z-score showed the strongest difference between the groups (R2 = 0.26, p < 0.001). The following cut-off values indicating need of revision due to instability were established: in 90° (15°) flexion-anterior translation 5.2 mm (22.4 mm), posterior translation 16.6 mm (13.2 mm); varus stress in 0° (20°-30°) flexion-inlay gap 5.2 mm (6.1 mm) or joint angle 6.1° (6.8°); valgus stress in 0° (20°-30°) flexion-inlay gap 4.6 mm (5.7 mm) or joint angle 5.2° (7.1°). CONCLUSION: Standardized stress radiographs are helpful tools for diagnosis of instability after TKA. The established cut-off values help to guide decision making in this challenging group of patients. However, laxity values should not be considered as the only criteria for diagnosis of unstable TKA. LEVEL OF EVIDENCE: IV.

A study of the symmetry of roots and root canal morphology in mandibular anterior teeth using cone-beam computed tomographic imaging in a Polish population.

BACKGROUND: The purpose of the study was to analyse mandibular anterior teeth in a Polish population and determine the symmetry of root and root canal morphology between the right and left side using cone-beam computed tomography (CBCT) scanning. MATERIALS AND METHODS: From 111 CBCT examinations, 303 pairs of equivalent mandibular anterior teeth were analysed on the right and left sides to evaluate symmetry. Axial, sagittal, and cross-sectional slices with a thickness of 0.2-0.25 mm were used. The number of root canals and their internal patterns were classified following Vertucci's criteria. RESULTS: All incisors in this study had 1 root. Canines usually had a single root and much less often had 2 roots. Type I and III root canal configurations were found most often, while type V and II configurations were less frequent. Significant compatibility between the left and right side was observed in all evaluated variables. Incisors had the highest symmetry with regard to the number of roots (100%). Second canals were observed more often in males than females, but only the results in lateral incisors were significant. CONCLUSIONS: This study provides supplemental information for dentists and should help them to better predict the morphology of mandibular anterior teeth in complicated cases in the Polish population. Symmetry was observed in roots and root canal morphology in all examined parameters.

[Assessment of ligament and tendon injuries of the elbow using magnetic resonance imaging]. / Band- und Sehnenverletzungen des Ellenbogens in der Magnetresonanztomographie.

An overview about the normal anatomy and frequent pathologies of tendons and ligaments of the elbow using MRI will be provided. The unique joint configuration and articulation, as well as passive ligamentous and active muscle structures as well as the unique configuration of the articulating components of the elbow contribute to joint stabilization. MRI is an essential imaging modality in patients with ligamentous injuries including the sequelae of joint dislocation as well as chronic pathologies such as long-standing and refractory tendinopathies. Ideally, when reporting MRI of the elbow, the joint is separated into its four compartments, anterior, posterior, medial and lateral, allowing precise, comprehensive and structured reporting.

Peripheral Arterial Tonometry in Pulmonary Vasculitis.

Vascular wall inflammation in primary vasculitides results in diminished vessel dilation and finally impaired blood flow, causing multiple organs dysfunction and ultimate damage. In granulomatosis with polyangiitis (GPA), the inflammatory process concerns small and medium sized vessels and its pulmonary location is often predominant. The pivotal role in the development of that pathology plays vascular endothelium. Endothelial vasodilatory function strongly depends on the instant production and release of nitrogen oxide (NO), a potent local factor controlling vascular tonus. NO output is triggered by a variety of stimuli, especially by ischemia. The endothelial vasodilatory ability can be measured indirectly by a few of methods, one of them is peripheral arterial tonometry (PAT). The method assesses reactive hyperemia, mediated mostly by NO release, as a response to vessel occlusion. The vasodilatory reaction depends on the quality of the endothelium which deteriorates with time of GPA disease progression. The aim of the present study was to estimate a correlation between the clinical status, reflected by the disease extent index (DEI), and the vasodilatory endothelial function reflected by the index of arterial reactive hyperemia (RHI), measured by PAT in 27 patients with GPA, having a significant pulmonary involvement. We found a moderate inverse correlation between DEI and log-transformed RHI (r = -0.46, p < 0.05). The conclusion is that impaired endothelial function, as assessed by RHI-PAT, might predict the GPA progression.

Identification and mitigation of stray laser light in the Thomson scattering system on the Madison Symmetric Torus (MST).

The Thomson scattering diagnostic on the Madison Symmetric Torus (MST) records excessive levels of stray Nd:YAG laser light. Stray light saturates the 1064 nm spectral channel in all polychromators, which prevents absolute electron density measurements via Rayleigh scattering calibration. Furthermore, stray light contaminates adjacent spectral channels for r/a ≥ 0.75, which renders the diagnostic unable to make electron temperature measurements at these radii. In situ measurements of stray light levels during a vacuum vessel vent are used to identify stray light sources and strategies for reduction of stray light levels. Numerical modeling using Zemax OpticStudio supports these measurements. The model of the vacuum vessel and diagnostic includes synthetic collection optics to enable direct comparison of measured and simulated stray light levels. Modeling produces qualitatively similar stray light distributions to MST measurements, and quantifies the mitigation effects of stray light mitigation strategies prior to implementation.

Safety and efficacy of ultra-high-dose, short-term thrombolysis with rt-PA for acute lower limb ischemia.

OBJECTIVES: The evaluation of success and complication rates of ultra high-dose recombinant tissue plasminogen activator (rt-PA) administered over a short time frame in the treatment of acute lower limb ischemia. METHODS: This was a prospective single-center study. The outcome of treatment in 97 patients with acute limb ischemia (<14 days) with the use of catheter directed rt-PA infusion was evaluated. The mean total dose of rt-PA was 54.1 mg (50-60 mg) and was administered for a mean of 2.51 hours (2-4 hours). Thrombolytic success was defined as 95% thrombolysis of an occluded segment with return of antegrade flow. Thirty-day complication and amputation-free survival rates were calculated. RESULTS: Thrombolytic success was achieved in 83.5%. Overall clinical success was 88.7%. The 30-day amputation-free survival rate was 93.8%. Major bleeding complications occurred in 10 patients (10.3%). There were two deaths (2.1%) and four amputations (4.1%). Long-term amputation-free survival was 70%. CONCLUSIONS: Administration of ultra-high doses of rt-PA over a short time period gives promising results. Such delivery improves patient tolerance by rapid restoration of limb perfusion; however further studies are required to confirm these results.

Improvements to the calibration of the MST Thomson scattering diagnostic.

Calibration of the Madison Symmetric Torus Thomson scattering system has been refined to improve temperature fluctuation measurements. Multiple avalanche photodiodes have been directly calibrated for use as reference detectors during calibration, improving accuracy and ease of use. From the absolute calibration we calculate corrections to the gain for variation in detector operating temperature. We also measure the spatial uniformity of detector responsivity for several photodiodes, and present a method of accounting for non-uniformity in the calibration process. Finally, the gain and noise enhancement are measured at multiple wavelengths to improve temperature and uncertainty measurements.

Pulse-burst laser systems for fast Thomson scattering (invited).

Two standard commercial flashlamp-pumped Nd:YAG (YAG denotes yttrium aluminum garnet) lasers have been upgraded to "pulse-burst" capability. Each laser produces a burst of up to 15 2 J Q-switched pulses (1064 nm) at repetition rates of 1-12.5 kHz. Variable pulse-width drive (0.15-0.39 ms) of the flashlamps is accomplished by insulated gate bipolar transistor (IGBT) switching of electrolytic capacitor banks. Direct control of the laser Pockels cell drive enables optimal pulse energy extraction, and up to four 2 J laser pulses during one flashlamp pulse. These lasers are used in the Thomson scattering plasma diagnostic system on the MST reversed-field pinch to record the dynamic evolution of the electron temperature profile and temperature fluctuations. To further these investigations, a custom pulse-burst laser system with a maximum pulse repetition rate of 250 kHz is now being commissioned.

Multipoint Thomson scattering diagnostic for the Madison Symmetric Torus reversed-field pinch.

The multipoint Thomson scattering diagnostic on the Madison Symmetric Torus (MST) is now fully operational with 21 spatial points, which cover the entire minor radius. Four full electron temperature profiles can be obtained during each MST discharge, with a variable delay between each profile. This system overcomes challenges that arise from the unique machine design, location, and plasma characteristics of MST. The machine design limits the maximum porthole diameter to 11.4 cm, requiring a compact, re-entrant, seven element lens for scattered light collection. Limited space near MST necessitates a long beam path for the two Nd:YAG lasers requiring a remote beam line adjustment system to suppress drift in the beam position due to thermal expansion of the building. Due to the remote location of the laser head, substantial design effort was put into the creation of a set of safety interlocks for the laser system. The dynamic nature of MST plasmas and the wide range of operating space require a versatile scattered light detection system consisting of filter polychromators with temperature controlled avalanche photodiode detectors. We also implement an insertable integrating sphere, which travels along the laser beam path through the vacuum vessel, for the alignment of both the fiber optics and the lasers.

Calibration of a Thomson scattering diagnostic for fluctuation measurements.

Detailed calibrations of the Madison Symmetric Torus polychromator Thomson scattering system have been made suitable for electron temperature fluctuation measurements. All calibrations have taken place focusing on accuracy, ease of use and repeatability, and in situ measurements wherever possible. Novel calibration processes have been made possible with an insertable integrating sphere (ISIS), using an avalanche photodiode (APD) as a reference detector and optical parametric oscillator (OPO). Discussed are a novel in situ spatial calibration with the use of the ISIS, the use of an APD as a reference detector to streamline the APD calibration process, a standard dc spectral calibration, and in situ pulsed spectral calibration made possible with a combination of an OPO as a light source, the ISIS, and an APD used as a reference detector. In addition a relative quantum efficiency curve for the APDs is obtained to aid in uncertainty analysis.

Treatment of acute ischemic brain infarction with the assistance of local intraarterial thrombolysis with recombinant tissue-type plasminogen activator.

BACKGROUND: Cerebral infarction is usually due to arterial occlusion. Prompt treatment with thrombolytic drugs can restore blood flow and improve recovery from an infarct. PURPOSE: To evaluate the clinical efficacy and safety of local intraarterial thrombolysis with recombinant tissue-type plasminogen activator (rtPA) in patients with acute middle cerebral artery (MCA) infarctions within 6 hours of the onset of symptoms. MATERIAL AND METHODS: Sixteen patients (10 females and six males) aged from 42 to 61 years, with acute MCA territory infarcts were selected for treatment with local i.a. rtPA up to 6 hours after the onset of symptoms. Patient selection was based on clinical examination, computed tomography (CT), and digital subtraction angiography (DSA). A clinical evaluation was performed before treatment, at the time of discharge, and 90 days post-procedure on the basis of modified Rankin and NIHSS scores. Controls (n = 16, nine females and seven males) aged from 51 to 70 years were treated only with intravenous anticoagulation using i.v. heparin infusion. The control group was evaluated with multidetector CT (MDCT) angiography performed on entry to the study and at 2-4 hours afterwards. RESULTS: Eight patients (50%) achieved a modified Rankin score of 2 or less as the primary outcome after 90 days follow-up. The secondary clinical outcome at 90-day follow-up was as follows: NIHSS score < or =1, three (19%) of the patients; NIHSS score > or =50% decrease, nine (56%) of the patients. A recanalization rate of 75% was achieved in 12 of the 16 treated patients, but only 12.5% in two of the 16 patients in the control group. Intracerebral hemorrhage occurred in two (12.5%) of the patients in the treatment group, but in only one patient (6%) in the control group. There were no deaths in the treated group after thrombolysis up to the time of discharge; however, during the 90-day follow-up, two patients died compared to three patients in the control group (19% vs. 12.5% mortality rate). CONCLUSION: Patients with cerebral infarction who were treated within 6 hours of onset using intraarterial rtPA thrombolysis had a significantly improved clinical outcome 90 days after the procedure compared to patients treated only with intravenous anticoagulation.

Primary stenting in the treatment of focal atherosclerotic abdominal aortic stenoses.

AIM: To evaluate the results of primary stent placement in focal atherosclerotic aortic stenoses using balloon expandable stents. MATERIALS AND METHODS: Twenty-six primary balloon expandable stent placements in the abdominal aorta were performed and reviewed. All the aortic stenoses were atherosclerotic. Patients were followed up by ankle/brachial pressure indices (ABPI) and Doppler ultrasound (US) at 24h after procedure and at 12 and 24 months. Follow-up angiograms were performed at 12 months. RESULTS: Twenty-six stents in 26 patients were placed in the infrarenal aorta. All procedures were technically successful and immediate clinical success was obtained. The mean ABPI significantly improved from 0.52+/-0.10 to 0.94+/-0.09 within 24h after procedure, and remained at 0.90+/-0.12 between 12 and 24 months follow-up (mean 18 months). There was full haemodynamic success at hospital discharge and at 12 and 24 months after the procedure. Clinical success at 12 and 24 months (mean 18 months) was defined as an improvement in the Fontaine classification by at least one class compared with the pre-procedure class and was shown to be 100%. CONCLUSION: In summary, we report that primary stenting is a safe and effective alternative to surgery in cases of symptomatic stenosis of the infrarenal abdominal aorta. The excellent intermediate term results suggested that we would recommend primary stenting as the treatment of choice for focal atherosclerotic stenoses of the infrarenal aorta in selected patients.

Popliteal vein aneurysm.

The incidence of a popliteal vein aneurysm is extremely low. Two cases of this rare venous anomaly are described. The epidemiology, morphology, and diagnostic methods are discussed and the potentially dangerous complications and treatment methods are presented.

Emergency Use of Stent and rtPA with Mechanical Cloth Defragmentation for a Thromboembolic Complication during GDC Coil Treatment of an Acutely Ruptured Basilar Tip Aneurysm.

Thrombotic occlusion of both posterior cerebral arteries occurred during embolization of an acutely ruptured basilar tip aneurysm. Intracranial stenting and continuous superselective infusion of rtPA was administered combined with mechanical clot fragmentation to reestablish normal vessel flow. DSA disclosed that normal vessel patency was achieved within 30 min. There were no adverse events related to rtPA administration and the patient recovered from the embolization with minor neurologic deficit as present before the procedure.

[Evaluation of the diagnostic value of color Doppler ultrasound examination of salivary gland neoplasms and metastatic tumors from the facial bones]. / Ocena wartosci diagnostycznej ultrasonograficznego badania Dopplerowskiego w kolorze w guzach slinianek i guzach przerzutowych szyi z twarzoczaszki.

The aim of the study was to evaluate usefulness of colour Doppler ultrasound examination in diagnosing the salivary gland tumours and the metastatic tumours of the neck originating from the facial part of the skull. Epidemiology and histopathology of the neoplasms involving the salivary glands and the facial skeleton were discussed including the route of their spreading to the neck. The author presents update techniques of bony face radiologic imaging and basic principles of modern colour Doppler ultrasound. The examinations with the use of a colour Doppler equipment-Acuson 128-XP 10 were performed in 150 patients with the neck tumours. The exact location, size, morphology and blood supply were assessed using B and B colour mode. Then some big neck vessels like the common, internal and external carotid artery, vertebral artery, internal jugular vein were visualized. All the patients were divided into three groups according to what they were suffering from: sialoadenitis, benign and malignant tumours. The obtained results were compared and confronted with clinical features. The pattern of vascularization failed to allow for establishing preliminary diagnosis in patients in each group. Within the first group, with inflamed glands did not compress the neck vessels. Of all the patients with benign tumours, extrinsic compression on the internal jugular vein and the carotid arteries was found in 16 and 14 patients respectively. In the third group of patients with malignant disease, compression on the veins was detected in 10 cases while 5 tumours compressed the arteries. The invasion involved the internal jugular vein in 7 patients while the common and internal carotid arteries were invaded in 6. The vertebral artery was never found to be affected. It was demonstrated that compression on veins resulted in disturbing the flow which was not observed as far as the arteries were concerned. Disturbing in the flow of veins and arteries was disclosed in cases of invasion. Atheromatosis was detected in patients of each group, 7 of them had to be operated on due to a stricture within the proximal part of internal carotid artery. The results of the study express high diagnostic value of colour Doppler ultrasound examination in the neck tumours. The examination should be obligatory performed as one of the first diagnostic measures after admitting a patient. The method seems to be of very little use in diagnosis differentiating inflammation, benign and malignant salivary gland tumours and metastatic masses of the neck hence some other diagnostic procedures should be here employed.

[How does carotid artery stenosis increase?]. / Jak powieksza sie zwezenie tetnicy szyjnej?

In 25 patients with carotid artery stenosis equal or higher than 40% colour doppler examinations were performed 105 times. The aim of this study was estimate the dynamics of progress of carotid artery stenosis. The mean time of observation was 22.5 months. In 11 (44%) patients there was no progress of stenosis, in 6 (24%) a leap progress over 30% of arterial lumen, and in 8 (32%) patients the progress of carotid artery stenosis were gradual and slow. The leap progress of carotid artery stenosis was usually caused by eruption or dissection of atherosclerotic plaque located in carotid bifurcation and this situation poses especially high risk of stroke.

[How quickly does an abdominal aortic aneurysm grow?]. / Jak szybko powieksza sie tetniak aorty brzusznej?

86 patients with Abdominal Aortic Aneurysm was assessed by abdominal ultrasound with respect to growth rate. For aneurysms with diameter 3-4 cm, mean growth rate was 0.215 mm per month, for aneurysms 4-5 cm was 0.33 mm per month and for aneurysms with AP diameter bigger than 50 mm the mean growth rate was 0.78 mm per month.

[Results of thrombolytic therapy with streptokinase for chronic deep vein thrombosis]. / Wyniki leczenia trombolitycznego streptokinaza przewleklej zakrzepicy zyl glebokich.

69 patients with DVT at least 1 week after acute symptoms was treated with streptokinase (Mean time 4 weeks after acute symptoms). Patients was divided for two groups: 1. with not entire main segments of deep vein occlusion and 2. with entire occlusion of segments of deep vein. Estimation of thrombolytic efficacy was performed by C. Theory. In the 1. group we achieved 23.8% of total obliteration and in 28.6% not entire. In the group 2. we achieved only 24.9% of partial obliteration. Intravenous streptokinase could be effective as well in long lasting deep vein thrombosis.

[Changes in the visual system of patients with carotid artery occlusion]. / Zmiany w narzadzie wzroku u chorych z niedroznoscia tetnic szyjnych.

The authors presented results of visual system examination in 28 persons in whom disturbances of blood flow in carotid arteries were diagnosed with colour doppler ultrasonography. The patients underwent routine ophthalmological examination, including kinetic and static perimetry. Ocular signs only, with no neurological changes, were found in 46% of patients. In 21% of cases there were episodes of transient blindness; homonymous hemianopsia occurred in 10%, acute ischaemic optic neuropathy in 11%, and secondary neovascular glaucoma in 14% of patients.

Absolute bioavailability of cefixime in man.

In a four-way cross-over study, the absolute bioavailability of cefixime was determined in 16 healthy volunteers. Each subject received a single 200-mg dose as an intravenous (IV) and oral solution, and 200-mg and 400-mg capsule doses of the drug. Blood and urine samples were collected for 24 hours after each dose. Cefixime was well tolerated after IV and oral doses of the drug and no serious drug-related adverse effects were observed. The maximal serum concentration (Cmax) of cefixime following the 200-mg oral solution and 200-mg and 400-mg capsule doses were 3.22, 2.92, and 4.84 micrograms/mL, respectively. Mean area under the serum concentration time curves (AUC) following the IV, 200-mg oral solution, and 200-mg and 400-mg capsule doses were 47.0, 26.0, 23.6, and 39.4 micrograms.hr/mL, respectively. Mean elimination half-life values of the drug were comparable after oral and IV doses, ranging from 3.2 to 3.5 hours. Based on serum AUC values, the absolute bioavailability of cefixime was 52.3%, 47.9%, and 40.2% after the 200-mg oral solution, 200-mg capsule and 400-mg capsule doses, respectively. Respective ratios based on 24-hour urinary recovery data were 44.7%, 41.7%, and 40.5%. Therefore, the results show that the percent of cefixime adsorbed after 200-mg and 400-mg oral doses was similar.