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PubMedDate not supplied

[Magnetic resonance of the elbow: technique optimization and definitions of normal anatomical features and their variations].

INTRODUCTION: MRI is a very accurate technique to study the elbow joint, tendon, ligament and chondral structures. In the last years elbow disorders were described by several MR investigators, while we studied MR capabilities in depicting normal elbow anatomy. This investigation might permit the correct differentiation of normal from abnormal MR patterns. MATERIAL AND METHODS: Eleven healthy volunteers (6 men and 5 women, mean age: 27.5 years) were examined. All studies were performed on a 1.5 T imager (Magnetom SP 4000) with two types of receiver: the knee coil was used in 7 volunteers examined in the prone position, with the arm above their head, the elbow extended and the forearm supine and the shoulder coil was used in 4 volunteers examined in the prone position, with the arm above their head, the elbow flexed and the forearm prone. We acquired T1-weighted SE sequences (TR/TE = 690/15 ms, FA 90 degrees, MA 256 x 512, NEX 2,20 3-mm sections with .3-mm interslice gap, FOV 20-22 cm) on the axial, coronal and sagittal planes and T2-weighted GE sequences (TR/TE = 450/10 ms, MA 256 x 256, 3 NEX, 18 4-mm sections with .4-mm interslice gap, FOV 13-18 cm) on the coronal plane. Two MR-expert radiologists studied the images and identified the main anatomical structures of the elbow and 12 smaller reference elements (2 anatomical variants, 4 ligaments, 3 nerves and 3 arteries) describing their MR appearance and pointing out the most effective planes for their representation. Finally, the image quality of the knee coil was compared with that of the shoulder coil. RESULTS: All bones were clearly depicted on the coronal and axial planes, while the semilunar groove and its anatomical variants were best seen on the sagittal plane. The joint cartilage was best depicted on the coronal plane with T2-weighted GE sequences. Collateral ligaments were best seen with the elbow extended and the forearm supine (knee coil), on coronal T1-weighted SE images, where the radial and ulnar collateral ligaments were visible in 71.4% and 85.7% of the subjects, respectively. Annular ligaments, muscles and tendons were best demonstrated on the axial plane with the elbow extended and the forearm supine (knee coil), while the triceps tendon was best recognized on the sagittal plane with the elbow flexed and the forearm prone (shoulder coil). Vessels and nerves were also best seen on the axial plane with the elbow extended and the forearm supine; in particular, the median nerve was visible in 71.4% of the subjects. DISCUSSION AND CONCLUSION: MRI is very effective in representing elbow anatomical structures. Its accuracy depends on elbow (flexed or extended) and forearm (prone or supine) position. The coronal images with the elbow extended and the forearm supine (knee coil) are the most effective to show the ligaments and the joint surfaces between the radial head and the coronoid process of ulna with the capitellum and trochlea of distal humerus, while the axial images best depicted the muscles, vessels and nerves. The coronal and axial planes, with the elbow flexed and the forearm prone (shoulder coil) are poorly effective for anatomical detailing, even though this position is more comfortable for the patient, while the sagittal plane is best suited to depict the triceps tendon. This position may be used when the elbow cannot be fully extended or when the triceps tendon is studied.

Adult↗

PubMed2002

[Can lung protective ventilation methods modify outcome?--A critical review].

A large body of experimental and clinical work leaves no room for doubt that mechanical ventilation can contribute to the progression of a lung disease or, in the worst case, produce acute pulmonary damage. The pathophysiological processes involved have been described as barotrauma, volutrauma, atelectrauma and biotrauma. In response, a socalled lung-protective ventilation strategy has been proposed, especially for patients with acute respiratory distress syndrome (ARDS). Such an approach seeks to apply limited airway pressures, small tidal volumes and appropriate levels of positive end-expiratory pressures even if, as a consequence, non-physiological gas exchange values (i.e. elevated PaCO2-levels) need to be tolerated. A recent large prospective randomized trial demonstrated reduced mortality rates using such a strategy. To support lung-protective ventilation in ARDS patients, an array of therapeutic measures has been proposed, including meticulous attention to fluid and transfusion management, prone position, extracorporeal membrane oxygenation (ECMO), inhalation of nitric oxide, implementation of spontaneous breathing, partial liquid ventilation and tracheal gas insufflation. Of these, only prone positioning has become part of routine clinical management, while ECMO is applied in selected cases only. Unfortunately, thus far, none of these measures has passed the litmus test of a randomized controlled trial. Recent large prospective observational studies, however, suggest that only an optimized concert of therapeutic interventions, but not a single measure alone, may improve the outcome of ARDS patients.

Animals↗

PubMed1992

Gastric residuals in preterm babies.

The gastric residual (GR) volume was measured in 50 healthy preterm babies, 38 appropriate-for-dates (AFD), and 12 small-for-dates (SFD) with gestational age of 28-36 weeks. The mean basal 4-hour gastric residual (B4 GR) volume was 2.8 +/- 0.63 ml in parenterally fed babies. There was a marked decrease in the residuals from 20.7 +/- 15.2 per cent (mean +/- SD) on day 4 to 8.6 +/- 4.3 per cent on day 7 (P < 0.001). Of the 27 infants fed with expressed breastmilk (EBM), mean GR was 24.4 +/- 10.2 per cent in supine and 12.8 +/- 4.3 per cent in prone position (P < 0.01). Twenty-one babies nursed in the prone position showed a mean GR volume of 12.8 +/- 4.3 per cent with EBM and 13.6 +/- 2.7 per cent with milk formula. No difference was noted in the gastric residuals of AFD v. SFD babies. No linear correlation was found between increase in abdominal girth and GR. However, if the increase in abdominal girth was at least 2 cm or more, a GR of 23 per cent or more was observed. This should be taken as warnings to reduce or withhold oral feeds.

Gastric Emptying↗

PubMed1989

Computed tomography in the diagnosis of asbestos-related thoracic disease.

High-resolution computed tomography (HRCT) has improved the radiologist's ability to detect and potentially quantify the abnormalities of asbestos exposure. It has proved to be more sensitive than chest radiography for detecting pleural plaques and for discriminating between pleural fibrosis and extrapleural fat. HRCT is also more sensitive than chest radiography or conventional CT for detecting parenchymal abnormalities in asbestos-exposed persons. The HRCT findings that correlate with other parameters of asbestosis include (1) septal and centrilobular thickening, (2) parenchymal fibrous bands, (3) honeycomb patterns, (4) subpleural density persisting in the prone position, and (5) subpleural curvilinear lines that persist in the prone position. CT has an important role in evaluating benign and malignant lung and pleural masses in asbestosis.

Asbestosis↗

PubMed2004

[Anesthetic management of a hemodialysis-dependent patient for the brain tumor resection with CHDF].

A 64-year-old man was scheduled for resection of brain tumor in the prone position. He had been on hemodialysis for three years. Anesthesia was induced using propofol, fentanyl, and vecuronium, and maintained with isoflurane and nitrous oxide in oxygen. Transesophagial echocardiography (TEE) was useful for maintaining fluid balance. To prevent bleeding tendency and to maintain electrolyte balance, continuous hemodiafiltration (CHDF) without anti-coagulant drugs was utilized for fluid management. Surgery was performed in the lateral position since the application of CHDF was impossible in the prone position. Approximately 3500 ml of blood was lost and 18 units of packed blood cells and 18 units of flesh frozen plasma were administered. We occasionally checked activated clotting time and platelet count during surgery, but they were kept in normal ranges. In this case, we were able to achieve proper intraoperative fluid management using TEE and CHDF.

Anesthesia↗

PubMed2006

[Reducing the risk of sudden infant death syndrome through safe sleep practices].

Sudden infant death syndrome (SIDS) is the unexplained sudden death of an infant under one year of age. In Taiwan, although the number of SIDS cases decreased between 1997 and 2003, the ratio for the number of such cases to infant mortality has been consistently increasing. Even though the cause of SIDS is unknown, risk factors have been identified in the literature on the subject. Nurses may help in reducing the risk of SIDS by educating parents about the risk factors. The purpose of this paper is to describe SIDS and to recommend nurses to implement the new recommendations of the American Academy of Pediatrics (AAP) to reduce the risk of SIDS. Released in 2005, these emphasize the importance of the prone position, the use of a pacifier during sleep, and the dangers of using soft bedding and of bed sharing. Side position is no longer recommended as a rational alternative of prone position. The recommendations also indicate the need to educate secondary caregivers and health care providers about SIDS.

Humans↗

PubMed2005

Effect of static stretching of quadriceps and hamstring muscles on knee joint position sense.

OBJECTIVES: To evaluate if a stretch regimen consisting of three 30 second stretches would alter joint position sense (JPS). METHODS: A blinded, randomised, cross over design with a washout time of 24 hours was used with 20 healthy volunteers. JPS was estimated from the ability to reproduce the same position in one knee (target versus estimated angle) expressed as the difference between target and estimated angle (constant error, CE). Measurements were repeated three times in a sitting and a prone position on the dominant leg measured before and immediately after the static stretch. The static stretch consisted of a 30 second stretch followed by a 30 second pause, repeated three times. RESULTS: At baseline, the mean (SD) CE was -2.71 (3.57) degrees in the sitting position. No difference (p = 0.99) in CE between stretching and control was observed (0.00; 95% confidence interval -0.98 to 0.99). At baseline, the CE was -3.28 (4.81) degrees in the prone position. No difference (p = 0.89) in CE between stretching and control was observed (0.12; 95% confidence interval -1.52 to 1.76). CONCLUSION: A static stretch regimen had no effect on JPS in healthy volunteers.

Adult↗

PubMed1999

Increased mast cell tryptase in sudden infant death - anaphylaxis, hypoxia or artefact?

BACKGROUND: Increased concentrations of mast cell tryptase in post mortem blood have frequently been observed in sudden infant deaths but the cause of this has not yet been clarified. OBJECTIVE: The aim was to evaluate factors (immunological, morphological and anamnestic data) behind the observed increase in mast cell tryptase in sudden infant deaths with elevated tryptase. METHODS: Mast cell tryptase and total immunoglobulin (Ig) E were measured in post mortem sera from 44 infants younger than 1.5 years. Radioallergosorbent tests were performed for possible allergens (mixture for relevant food allergens, Phadiatop and latex). IgG subclasses, IgM, and complement factors (C3, C4 and factor B) were measured with radial immunodiffusion. Mast cells, labelled with antibodies against mast cell tryptase, were counted in the lungs and heart. The circumstances of death and medical history of the deceased infant and family were obtained through police and hospital records. RESULTS: In 40% of the SIDS cases tryptase was elevated (>10 microg/L). Total IgE in serum was increased in 33% compared with clinical reference values but showed no association with mast cell tryptase. RAST tests were positive in three cases. In one of these cases both tryptase and total IgE were elevated. The only variable that was associated with high tryptase values was prone position at death (P < or = 0.05 ). Allergy or asthma in the family were alleged in 50% of the cases, but was not associated with elevated tryptase or IgE. Children with elevated total IgE also displayed high concentrations of IgG1 and IgG2. Infants who died in the spring had significantly higher IgE than the others (P < or = 0.05). CONCLUSION: The results do not support the hypothesis that the elevated tryptase concentrations in sudden infant death are caused by allergy. The association between prone position at death and elevated tryptase could hypothetically be explained by mast cell degranulation due to, for example, a hypoxic stimulus in these infants.

Anaphylaxis↗

PubMed1997

Radionuclide-guided stereotactic prebiopsy localization of nonpalpable breast lesions with normal mammograms.

UNLABELLED: Scintimammography with 99mTc-sestamibi can be used as a complementary technique to improve the mammogram's sensitivity and specificity for detection of breast carcinoma. We have observed in some patients focal areas of increased 99mTc-sestamibi uptake with no corresponding abnormalities on physical examination or mammogram. A phantom device and a special needle were designed to stereotactically localize these lesions before biopsy. METHODS: After intravenous injection of 30 mCI (1110 MBq) of 99m Tc-sestamibi, a prone lateral image of the abnormal breast was obtained. With the patient in the prone position, the breast was compressed with two fenestrated plates in the prone position. The x and y coordinates of the abnormal hot spot of the breast were determined. The z coordinate of focal 99mTc-sestamibi uptake was determined by advancing a localizer needle through a selected predetermined hole of the fenestrated plate using real-time visualization on the persistence monitor. The tip of the opturator inside the needle is welded with 57Co to determine the depth of the hot spot in the breast. RESULTS: Three women, all of whom had normal mammogram and breast physical examinations, were studied using 99mTc-sestamibi prone breast imaging. Pre-excisional biopsy needle localization of abnormal focal uptake was performed. Two women demonstrated infiltrative ductal carcinoma, and the third had proliferative fibrocystic disease of the breast. CONCLUSION: Our initial experience demonstrates that nuclear medicine guided stereotactic needle biopsy of the breast in patients with positive scintimammograms is technically feasible. In the future, this technology will enable us to detect breast carcinoma in the absence of clear-cut clinical and mammographic findings.

Adult↗

PubMed2000

Does head positioning influence anterior chamber depth in pseudoexfoliation syndrome?

PURPOSE: Phacodonesis can occur in pseudoexfoliation syndrome because of impaired zonular support. This study investigates whether the increased mobility of the lens influences anterior chamber depth in patients with pseudoexfoliation while assuming a prone position. METHODS: Central anterior chamber depth was measured in 39 patients with clinically apparent unilateral pseudoexfoliation and elevated intraocular pressure. Patients were placed in a face-up position for 5 minutes, at which time anterior chamber depth and axial length were measured by A scan, and intraocular pressure was measured by Tonopen (Oculab, La Jolla, CA) in both eyes. The measurements were repeated on both eyes after 5 minutes in a face-down position. RESULTS: No significant differences in intraocular pressure or axial length between the prone and supine positions were found in either eye. Anterior chamber depth in eyes with pseudoexfoliation decreased from a mean of 3.08 mm in the supine position to a mean of 2.95 mm in the prone position, whereas mean anterior chamber depth in the fellow eyes decreased from 3.01 mm to 2.97 mm. The decrease in anterior chamber depth when facing down in the eyes with pseudoexfoliation was significantly greater than in the fellow eyes. CONCLUSIONS: In patients with clinically apparent unilateral pseudoexfoliation, the lens seems to be more mobile in the affected eye. This results in a shallower anterior chamber when the head is placed in a prone position. Whether this fact might potentially lead to transient pupillary block when engaging in activities such as facing down while reading warrants further study.

Anterior Chamber↗

PubMed2003

Alert for perioperative visual loss: an unusual presentation of an orbital haemangioma during spinal surgery.

A 62-year-old man with a history of non-insulin-dependent diabetes mellitus, hypertension and obesity, presented for elective lumbar laminectomy for spinal canal stenosis. Twenty minutes after placement in the prone position, he developed left orbital proptosis. The surgery was deferred and a subsequent CT scan showed an orbital haemangioma. This case highlights the importance of meticulous attention to eye-care for patients in the prone position.

Exophthalmos↗

PubMed2003

Thoracodorsal sympathectomy for severe hyperhydrosis: posterior bilateral versus unilateral staged sympathectomy.

The aim of this study was to compare the results of simultaneous bilateral thoracodorsal sympathectomy in the prone position with those of anterolateral sympathectomy performed in two staged, separate procedures for the treatment of bilateral excessive sweating of the hands and axillae, and to describe our technique for bilateral, simultaneous thoracodorsal sympathectomy. From July 1995 to March 2001, 202 thoracodorsal sympathectomies were done in 101 patients for severe hyperhydrosis. There were 79 females (age range 20-46) and 22 males (age range 19-65). In 52 patients, anterolateral sympathectomies were performed in the supine position, using unilateral lung collapse, with both sides operated on in two separate, staged procedures. In 49 patients, bilateral sympathectomy was conducted during a single procedure, in the prone position, without using unilateral lung collapse. In comparing the results from these two methods, we concluded that simultaneous bilateral thoracodorsal posterior sympathectomy, has comparable safety, may improve outcome, decreases in half the number of hospital admissions, and produces a significant overall reduction in cost when compared with staged anterolateral sympathectomy for the treatment of severe hyperhydrosis.

Adult↗

PubMed1997

Influence of modifications in breast irradiation technique on dose outside the treatment volume.

PURPOSE: There is increasing interest in potential long-term effects of radiotherapy (RT) in patients treated for breast cancer, particularly those in whom long-term survival can be expected. The purpose of the present study was to determine the effects of treatment techniques, including patient positioning (supine vs. prone) on the absorbed dose in organs at a distance from the treatment volume in breast RT. METHODS AND MATERIALS: Dose distribution was studied in a Rando-Alderson phantom, modified with a simulated left breast of tissue-equivalent material. RT delivery was studied using 60Co and 6 MV x-ray beams, as well as electrons and a 192Ir source for tumor bed boost RT. Doses were measured in several organs and tissues of interest using LiF thermoluminescent dosimeters. Tangential breast RT was simulated using both supine and prone positioning. RESULTS: Peripheral doses generally decreased approximately exponentially with distance from the edge of the treatment field. Peripheral doses in various target organs were significantly higher for supine than for prone tangential breast RT (for 50 Gy prescribed dose): 0.50 Gy vs. 0.25 Gy for the upper abdomen, 0.05 Gy vs. 0.02 Gy for pelvic organs, 0.17 Gy vs. 0.08 Gy for active bone marrow, and 0.47 Gy vs. 0.12 Gy for ipsilateral lung (discounting lung in primary beam). CONCLUSIONS: The present study suggests that peripheral doses in several organs and tissues of interest can be reduced by 40 to 75% by prone tangential breast RT. These results may have implications for future strategies in the treatment of screen-detected breast cancer.

Abdomen↗

PubMed2003

A variant of incaprettamento (ritual ligature strangulation) in East Timor.

Incaprettamento is a ritualized form of ligature strangulation often associated with the Italian Mafia. The hallmarks include ligature strangulation and binding of the body in a highly stereotyped fashion. The bindings include tying the wrists and ankles together, with the body in the prone position (similar to "hogtying"), and an additional ligature encircling the neck and attached to the bindings of the extremities. The binding of the body may be performed after death is inflicted by ligature strangulation, or it may be associated with self-strangulation, as shown by the arrangement of ligatures and the position of the body. A case with great similarities to incaprettamento, in which the body was exhumed from a grave in East Timor, is described in detail. However, in addition to prone-position binding and a hyoid fracture, chopping wounds of a knee and blunt trauma to the posterior torso were found. The implication of these wounds is discussed in relation to incaprettamento.

Ankle Injuries↗

PubMed2002

Lateral decubitus position for percutaneous nephrolithotripsy in the morbidly obese or kyphotic patient.

BACKGROUND AND PURPOSE: Morbidly obese or debilitated patients do not tolerate the prone position used for percutaneous nephrolithotripsy (PCNL) well and may suffer from severe cardiorespiratory compromise in this position. The purpose of this study is to demonstrate a simple way to overcome this difficulty. PATIENTS AND METHODS: Two morbidly obese patients, ages 48 and 32 years, with Body Mass Indices of 47.5 and 43.2 and a 68-year old patient severely debilitated by multiple cerebral infarctions, ischemic heart disease, and kyphosis suffered from relatively high renal stone burdens. For PCNL, the patients were placed in the lateral decubitus position. To obtain an anteroposterior projection in this position, the C-arm fluoroscopy unit was tilted to one side and the operating table to the other. Tract dilation, stone fragmentation, and fragment extraction were performed with the patient in this position. RESULTS: An attempt to perform PCNL in the prone position in the first patient was aborted because of severe hypoxemia and hypercarbia. In the lateral decubitus position, the procedures were easily performed in all patients without any complications. It was noted that by rotating the C-arm to a perpendicular position, it was possible to perform nephroscopy and use fluoroscopy simultaneously. CONCLUSION: We highly recommend using the lateral position for PCNL in morbidly obese patients and in patients suffering from kyphosis. This position is safe and convenient.

Adult↗

PubMed1995

A community-based survey of infant sleep position. Pediatric Research in Office Practices Network.

OBJECTIVE: To determine prevalent infant sleep positions before and after the American Academy of Pediatrics position statement of 1992 and to identify determinants of sleep position. METHOD DESIGN: cross-sectional survey. SETTING: private and hospital-sponsored general pediatric offices. PARTICIPANTS: parents of infants younger than 7 months of age. RESULTS: Eight hundred fifty-two care givers completed surveys during the 5-week study. Fifty-four percent of the study infants were put to sleep in the prone position. In 416 families with more than one child, however, 75% of the youngest siblings had been put to sleep in the prone position at the same age. Gender, race, family income, maternal smoking, and birth weight were not associated with choice of sleep position. CONCLUSIONS: There has been a change in infant sleep positioning in the desired direction since the American Academy of Pediatrics statement. However, 54% of the study infants were still being put to sleep prone.

Age Factors↗

PubMed1995

Experimental retroperitoneal endoscopic surgery.

Techniques for retroperitoneal endoscopic procedures with the patient in prone position were evaluated in experimental studies in the pig. Nephrectomy, para-aortic lymph node dissection, lumbar sympathectomy and assisted aorto-femoral bypass were performed and the experience is reported herein. The prone position contributes to the creation of the retroperitoneal working space and eliminates the need for extensive retraction and thus for additional ports. The modified open Hasson technique was found to be the preferred retroperitoneal access procedure.

Animals↗

PubMed1999

Do cry features reflect pain intensity in preterm neonates? A preliminary study.

The purpose of this study was to investigate if cries from preterm neonates would reflect changes in pain intensity following interventions. The cries from 25 preterm neonates from an original sample of 122 were audiorecorded while the infant was undergoing heelstick during a randomized crossover design testing the efficacy of: pacifier with sucrose or water, or prone position as compared to standard care. Both pacifier conditions reduced procedural pain according to a validated composite pain measure (the Premature Infant Pain Profile). There were proportionately fewer cries in the two pacifier groups compared to the prone positioning and standard care groups, and cry duration was positively correlated with PIPP scores. However, neither cry duration nor fundamental frequency reflected group differences. Further research is needed to determine if cry is a sensitive and valid indicator of pain in preterm infants.

Blood Specimen Collection↗