A population-level post-screening treatment cost framework to help inform vision screening choices for children under the age of seven

PURPOSE/BACKGROUND

Visual acuity (VA) screening in children primarily detects low VA and amblyopia between 3 and 6 years of age. Photoscreening is a low-cost, lower-expertise alternative which can be carried out on younger children and looks instead for refractive amblyopia risk factors so that early glasses may prevent or mitigate the conditions. The long-term benefits and costs of providing many children with glasses in an attempt to avoid development of amblyopia for some of them needs clarification. This paper presents a framework for modeling potential post-referral costs of different screening models once referred children reach specialist services.

METHODS

The EUSCREEN Screening Cost-Effectiveness Model was used together with published literature to estimate referral rates and case mix of referrals from different screening modalities (photoscreening and VA screening at 2, 3-4 years and 4-5 years). UK 2019-20 published National Health Service (NHS) costings were used across all scenarios to model the comparative post-referral costs to the point of discharge from specialist services. Potential costs were compared between a) orthoptist, b) state funded ophthalmologist and c) private ophthalmologist care.

RESULTS

Earlier VA screening and photoscreening yield higher numbers of referrals because of lower sensitivity and specificity for disease, and a different case mix, compared to later VA screening. Photoscreening referrals are a mixture of reduced VA caused by amblyopia and refractive error, and children with amblyopia risk factors, most of which are treated with glasses. Costs relate mainly to the secondary care providers and the number of visits per child. Treatment by an ophthalmologist of a referral at 2 years of age can be more than x10 more expensive than an orthoptist service receiving referrals at 5 years, but outcomes can still be good from referrals aged 5.

CONCLUSIONS

All children should be screened for amblyopia and low vision before the age of 6. Very early detection of amblyopia refractive risk factors may prevent or mitigate amblyopia for some affected children, but population-level outcomes from a single high-quality VA screening at 4-5 years can also be very good. Total patient-journey costs incurred by earlier detection and treatment are much higher than if screening is carried out later because younger children need more professional input before discharge, so early screening is less cost-effective in the long term. Population coverage, local healthcare models, local case-mix, public health awareness, training, data monitoring and audit are critical factors to consider when planning, evaluating, or changing any screening programme.

Availability of data for cost-effectiveness comparison of child vision and hearing screening programmes

OBJECTIVE

For cost-effectiveness comparison of child vision and hearing screening programmes, methods and data should be available. We assessed the current state of data collection and its availability in Europe.

METHODS

The EUSCREEN Questionnaire, conducted in 2017-2018, assessed paediatric vision and hearing screening programmes in 45 countries in Europe. For the current study, its items on data collection, monitoring and evaluation, and six of eleven items essential for cost-effectiveness analysis: prevalence, sensitivity, specificity, coverage, attendance and loss to follow-up, were reappraised with an additional questionnaire.

RESULTS

The practice of data collection in vision screening was reported in 36% (N = 42) of countries and in hearing screening in 81% (N = 43); collected data were published in 12% and 35%, respectively. Procedures for quality assurance in vision screening were reported in 19% and in hearing screening in 26%, research of screening effectiveness in 43% and 47%, whereas cost-effectiveness analysis was performed in 12% for both. Data on prevalence of amblyopia were reported in 40% and of hearing loss in 77%, on sensitivity of screening tests in 17% and 14%, on their specificity in 19% and 21%, on coverage of screening in 40% and 84%, on attendance in 21% and 37%, and on loss to follow-up in 12% and 40%, respectively.

CONCLUSIONS

Data collection is insufficient in hearing screening and even more so in vision screening: data essential for cost-effectiveness comparison could not be reported from most countries. When collection takes place, this is mostly at a local level for quality assurance or accountability, and data are often not accessible. The resulting inability to compare cost-effectiveness among screening programmes perpetuates their diversity and inefficiency.

A Comprehensive Overview of Vision Screening Programmes across 46 Countries

Purpose:

To describe and compare vision screening programmes and identify variance in number and type of tests used, timing of screening, personnel involved, monitoring and funding to be used as data for optimising, disinvesting or implementing future screening programmes.

Methods:

A questionnaire consisting of nine domains: demography & epidemiology, administration & general background, existing screening, coverage & attendance, tests, follow-up & diagnosis, treatment, cost & benefit and adverse effects was completed by Country Representatives (CRs) recruited from 47 countries.

Results:

The questionnaire was sufficiently completed for 46 Countries: 42 European countries, China, India, Malawi and Rwanda. Variation of provision was found in; age of screening (0–17 years), tests included (23), types of visual acuity (VA) test used (35 different optotypes), personnel (13), number of screens per child (median 5, range 1–32), and times VA tested (median 3, range 1–30). Infant screening is offered in all countries, whereas childhood vision screening is offered at least once in all countries, but not all regions of each country. All 46 countries provide vision screening between the ages of 3–7 years. Data on screening outcomes for quality assurance was not available from most countries; complete evaluation data was available in 2% of countries, partial data from 43%.

Conclusion:

Vision screening is highly variable. Some form of VA testing is being undertaken during childhood. Data collection and sharing should be improved to facilitate comparison and to be able to optimise vision screening programmes between regions and countries.

Acceptability of childhood screening: a systematic narrative review

Objectives

A systematic narrative literature review was undertaken to assess the acceptability of childhood screening interventions to identify factors to consider when planning or modifying childhood screening programs to maximize participation and uptake.

Study design

This is a systematic narrative literature review.

Methods

Electronic databases were searched (MEDLINE, EMBASE, PsycINFO via Ovid, CINAHL, and Cochrane Library) to identify primary research studies that assessed screening acceptability. Studies were categorized using an existing theoretical framework of acceptability consisting of seven constructs: affective attitude, burden, ethicality, intervention coherence, opportunity costs, perceived effectiveness, and self-efficacy. A protocol was developed and registered with PROSPERO (registration no. CRD42018099763)

Results

The search identified 4529 studies, and 46 studies met the inclusion criteria. Most studies involved neonatal screening. Programs identified included newborn blood spot screening (n = 22), neonatal hearing screening (n = 13), Duchenne muscular dystrophy screening (n = 4), cystic fibrosis screening (n = 3), screening for congenital heart defects (n = 2), and others (n = 2). Most studies assessed more than one construct of acceptability. The most common constructs identified were affective attitude (how a parent feels about the program) and intervention coherence (parental understanding of the program, and/or the potential consequences of a confirmed diagnosis).

Conclusions

The main acceptability component identified related to parental knowledge and understanding of the screening process, the testing procedure(s), and consent. The emotional impact of childhood screening mostly explored maternal anxiety. Further studies are needed to examine the acceptability of childhood screening across the wider family unit. When planning new (or refining existing) childhood screening programs, it is important to assess acceptability before implementation. This should include assessment of important issues such as information needs, timing of information, and when and where the screening should occur.

Management of nystagmus in children: a review of the literature and current practice in UK specialist services

Nystagmus is an eye movement disorder characterised by abnormal, involuntary rhythmic oscillations of one or both eyes, initiated by a slow phase. It is not uncommon in the UK and regularly seen in paediatric ophthalmology and adult general/strabismus clinics. In some cases, it occurs in isolation, and in others, it occurs as part of a multisystem disorder, severe visual impairment or neurological disorder. Similarly, in some cases, visual acuity can be normal and in others can be severely degraded. Furthermore, the impact on vision goes well beyond static acuity alone, is rarely measured and may vary on a minute-to-minute, day-to-day or month-to-month basis. For these reasons, management of children with nystagmus in the UK is varied, and patients report hugely different experiences and investigations. In this review, we hope to shine a light on the current management of children with nystagmus across five specialist centres in the UK in order to present, for the first time, a consensus on investigation and clinical management.

The Provision of Patient Information about Nystagmus

Aims

The aims of this study were to evaluate the current provision of patient information about nystagmus in orthoptic clinics in the UK and Ireland and to develop a standardised information pack about nystagmus.

Methods

A questionnaire was circulated to orthoptists in the UK and Ireland asking whether they had information to provide to patients with nystagmus, what was included in this information and how it could be improved. Orthoptists were also asked what should be included in a standardised information pack about nystagmus.

Results

Two hundred and thirty three orthoptists completed the questionnaire. One-third of responding orthoptists did not have information to provide to patients with nystagmus. Most reported the information available to them included details of support services and physical symptoms. Including information about living with nystagmus at different ages and long-term prognosis were the most common suggestions to improve information about nystagmus. More than half of orthoptists selected all the suggested topics to be included in a standardised information pack, with support services and long-term prognosis most frequently selected.

Conclusions

Only 67% of responding orthoptists had information about nystagmus to give to patients or their families. Ways to improve the current information and content considered important by orthoptists were taken into account to create a nystagmus information pack, which is now available online.

Inventory of current EU paediatric vision and hearing screening programmes

OBJECTIVE

To examine the diversity in paediatric vision and hearing screening programmes in Europe.

METHODS

Themes for comparison of screening programmes derived from literature were used to compile three questionnaires on vision, hearing, and public health screening. Tests used, professions involved, age, and frequency of testing seem to influence sensitivity, specificity, and costs most. Questionnaires were sent to ophthalmologists, orthoptists, otolaryngologists, and audiologists involved in paediatric screening in all EU full-member, candidate, and associate states. Answers were cross-checked.

RESULTS

Thirty-nine countries participated; 35 have a vision screening programme, 33 a nation-wide neonatal hearing screening programme. Visual acuity (VA) is measured in 35 countries, in 71% of these more than once. First measurement of VA varies from three to seven years of age, but is usually before age five. At age three and four, picture charts, including Lea Hyvarinen, are used most; in children over four, Tumbling-E and Snellen. As first hearing screening test, otoacoustic emission is used most in healthy neonates, and auditory brainstem response in premature newborns. The majority of hearing testing programmes are staged; children are referred after 1-4 abnormal tests. Vision screening is performed mostly by paediatricians, ophthalmologists, or nurses. Funding is mostly by health insurance or state. Coverage was reported as >95% in half of countries, but reporting was often not first-hand.

CONCLUSION

Largest differences were found in VA charts used (12), professions involved in vision screening (10), number of hearing screening tests before referral (1-4), and funding sources (8).

Temporary incyclotorsion following surgical correction of bilateral superior oblique palsy

We report three patients with acquired bilateral superior oblique paresis who had bilateral modified Harada-Ito procedures, which resulted in significant incyclotorsion (ranging from 6 degrees to 19 degrees ) on the first day postoperatively. For Case 1 this was the only procedure, while Cases 2 and 3 also underwent simultaneous bilateral inferior oblique weakening. This overcorrection decreased spontaneously over the following 8 months to leave all patients asymptomatic. One patient returned 8 years following the initial surgery with symptoms of diplopia and recurrence of excyclotorsion.

Diffuse lymphangiomatosis of bone

Two cases of lymphangiomatosis of bone, a very rare systemic condition characterized by both skeletal and parenchymal lesions, are presented. The skeletal changes have an appearance similar to haemangiomas in the spine, and soap-bubbly lesions in the flat bones. One case carried the diagnosis of eosinophilic granuloma for 18 years. The findings on MRI, which have not been previously well-established, are discussed.

Calcaneal fractures in diabetic patients

We would like to present 23 calcaneal fractures in 22 patients of whom 21 had type I diabetes mellitus. There appear to be three basic fracture types: (1) a superiorly displaced extra-articular avulsion fracture of the posterior calcaneus (or Iowa fracture), which occurred in 12 patients (five men, seven women); (2) a mid-calcaneal compression fracture in six patients (four men, two women), and (3) a cleavage or "wedge" type fracture in four patients extending from the calcaneal tubercle (one man, 3 women). All four of this last group of patients had a history of a chronic penetrating ulcer, and this is noteworthy since only one other patient out of the remaining 18 in groups 1 and 2 had a similar history. Most patients had decreased bone mineralization: 15 patients were on long-term, high-dose steroids, and 18 patients had either poor renal function or complete renal failure (11 of 12). Fourteen patients had received either renal or pancreas transplants. Eight patients were on restricted weight bearing prior to their fractures. We believe that diabetic patients are more prone to calcaneal fractures than the general population, and early diagnosis is imperative, followed by early treatment to prevent significant bony deformity.

Effects of capsular contracture on ultrasonic screening for silicone gel breast implant rupture

Unlike computed tomography and magnetic resonance imaging, ultrasound is an inexpensive test of potential use in detecting silicone gel breast implant (SBI) rupture. However, periprosthetic capsular contracture can make ultrasonic diagnosis of rupture difficult because the contracture-related radial folds inside the SBI can lead to a false-positive diagnosis of rupture. This study was conducted to determine the effects of capsular contracture on the ability of ultrasound to diagnose SBI rupture. Preoperative ultrasonic results of 122 SBIs were compared with surgical findings at the time of implant removal. The sensitivity and negative predictive values of ultrasound were lower in the presence of a contracted capsule (41.2% vs. 68.7%, p = 0.062; and 58.3% vs. 79.6%, p = 0.056 respectively). Ultrasound should be considered reliable in diagnosing SBI rupture only in the absence of a contracted capsule.

The use of MR imaging in the assessment and clinical management of stress reactions of bone in high-performance athletes

Based on experience, the authors believe that MR imaging is a useful tool in the assessment and management of stress fractures and stress phenomenum of bone. The use of standard, graded MR evaluation aides the assessment of a repetitive stress injury to bone by allowing a more accurate diagnosis of bone injury. This more accurate assessment has predictive value in estimating the duration of disability. The use of a standard, graded MR evaluation aides the management of repetitive stress injuries to bone by defining a low grade of stress fracture (i.e., grade 1 and 2) injuries and a high grade of stress fracture (i.e., grade 3 and 4). This grading system has implications in the management of stress fractures, allowing more individualized treatment for the elite athlete.

The prevalence of diffuse idiopathic skeletal hyperostosis (DISH) in two large American Midwest metropolitan hospital populations

OBJECTIVE

There are no published large-scale studies of the overall prevalence of diffuse idiopathic skeletal hyperostosis (DISH) and it has been proposed that the prevalence is greater than previously reported. We thus decided to review chest radiographs in a population of patients over 50 years of age seen at two large but differing metropolitan hospitals in a major American Mid-west city.

DESIGN AND PATIENTS

The posterior-anterior and lateral chest radiographs of 1363 patients were reviewed for evidence of DISH at the University of Minnesota Hospital and Clinic. There were 500 consecutive inpatient admissions, 540 consecutive patients who attended the outpatient clinics and 326 patients collected from our film archive. A population of 1001 patients seen at Hennepin County Medical Center was also studied. It was possible to subclassify this latter group with respect to race.

RESULTS AND CONCLUSION

Using strict criteria, i.e., four or more levels involved, the overall prevalence of DISH in the male population over age 50 years was 25% and in the female population over age 50 years was 15%. This prevalence climbed to 28% in males over 80 years and to over 35% in males over age 70 years. In females over 80 years, the prevalence was found to be 26%. Although our population base was small, DISH was found to be less common in the black, Native-American and Asian populations. The prevalence of DISH was also found to be far lower in a similar white population with osteoporosis. The overall prevalence of DISH was higher than expected in a predominantly white population over age 50 years with a lesser incidence in the black, Native-American and Asian populations, suggesting a genetic origin of the condition.

Use of MRI in evaluating postoperative changes in patients with bone and soft tissue tumors

We reviewed the clinical, surgical and magnetic resonance imaging (MRI) findings in 80 patients who underwent resection of primary benign or malignant bone or soft tissue tumors. There were 18 benign and 62 malignant tumors. Although 31 patients were originally thought to have recurrence, on review only 20 patients were considered to have recurred. Of these, three were found only to have postoperative changes at surgery. Seventeen patients actually had recurrence of tumor. We believe that the presence of an actual mass lesion on MRI is the cornerstone for the correct diagnosis of recurrent tumor.

The biomechanics of gravity-dependent traction of the lumbar spine

STUDY DESIGN

This study evaluated the biomechanical responses evoked by the use of a gravity-dependent, self-operated traction device. These responses were determined by radiographs and were correlated with the body weight of the patient who was supported by a seat strap.

OBJECTIVES

To examine the biomechanical effectiveness of the LTX 3000 Lumbar Rehabilitation System.

SUMMARY OF BACKGROUND DATA

The LTX 3000 Lumbar Rehabilitation System (Spinal Designs International, Minneapolis, MN) was used to administer the lumbar fraction. No previous study has been conducted on this device.

METHODS

For each of the 14 healthy male patients (age range, 19-69 years), lumbar lengthening, alterations in spinal curvature, and thoracic spine movement were assessed using radiographs taken: 1) before traction; 2) at 2, 10, and 15 minutes after the onset of traction; and 3) 2 minutes after traction was completed. Strain on the buttocks-supporting seat strap was recorded continuously during study sessions.

RESULTS

The entire patient pool displayed an average maximal lumbar lengthening of 6.39 +/- 4.21 mm. The amount of lumbar lengthening was influenced by the degree of thoracic immobilization and by the amount of prior LTX 3000 (Spinal Designs International) use. Significant curvature reduction was observed during and after traction for the entire patient pool. Strain measurements correlated well with the measured response in the radiographs.

CONCLUSIONS

Proper use of the LTX 3000 (Spinal Designs International) induces significant lumbar lengthening and curvature reduction in healthy patients. Measurements of body weight supported by the seat strap could help determine if thoracic immobilization has been achieved and if the patient is responding to the lumbar unloading.

"Incisura" of the ascending aorta and vascular pedicle width in the cardiac transplant patient

BACKGROUND

The purpose of this study was to evaluate three findings in cardiac transplant patients: the appearance, etiology, and incidence of "incisura" (a characteristic indentation) of the ascending aorta; the vascular pedicle width, which usually appears enlarged on standard chest radiographs; and clearing of the retrosternal clear space.

MATERIAL

Two hundred sixty-one cardiac transplantations were performed at the University of Minnesota before December 31, 1992. The appearance, etiology, and incidence of an incisura were studied; the vascular pedicle width was measured; and the rate of clearing of the retrosternal clear space was determined.

RESULTS

Forty-six percent of the patients whose ascending aorta could be visualized on the lateral chest radiogram showed an incisura. Approximately one third of the patients showed continued opacification of the retrosternal space postoperatively. The width of the vascular pedicle in this series of cardiac transplant patients measured 60.9 +/- 22.8 mm (standard deviation, 11.4 mm), in comparison to a normal of 48 +/- 5.0 mm.

CONCLUSIONS

An incisura of the ascending aorta and the widened vascular pedicle are normal postoperative chest radiographic findings in cardiac transplant patients and should not be misconstrued as abnormalities.

Lipoblastoma of the foot

Lipoblastoma is an uncommon benign lipomatous soft tissue mass of childhood, occurring most commonly in children less than 3 years of age. We present a case of lipoblastoma occurring in the foot of a 14-year-old boy and review the literature. The appearance of the mass on magnetic resonance imaging (MRI) is illustrated and is correlated with the findings at gross and microscopic pathological examination. A lobulated architecture, the presence of adipose tissue, thin nonenhancing septa, peripheral lobules of more immature and therefore less specific tissue, and a peripheral pseudocapsule were evident on MRI and at pathological examination.

Cyclops lesion

Postoperative impingement of the knee following ACL reconstruction does occur. MRI can be useful in the diagnosis of the patient who is not recovering as quickly as expected following surgical reconstruction. MRI allows the assessment of 1) tunnel position and alignment, 2) graft integrity, 3) the menisci for possible re-tear or extension of previous tears, and 4) joint for scar tissue and cartilaginous bodies either loose or fixed.

Hyperextension strain or "whiplash" injuries to the cervical spine

PURPOSE

To define "whiplash" radiologically.

MATERIAL AND METHODS

A full cervical spine radiographic series (including flexion and extension views) was reviewed in 40 patients with clinically proven "whiplash" injuries and compared to the radiographs in 105 normal controls. The level and degree of kinking or kyphosis, subluxation, and the difference in the amount of fanning between spinous processes on flexion and extension films were measured in each patient.

RESULTS

Localized kinking greater than 10 degrees and over 12 mm of fanning, often occurring at the level below the kinking or kyphosis, occurred mainly in the group of whiplash patients (sensitivity 81%, specificity 76%, accuracy 80%).

CONCLUSIONS

Localized kinking greater than 10 degrees and fanning greater than 12 mm are useful measurements by which to separate patients with true whiplash injuries from those with minor ligamentous tears. Flexion and extension views are essential to help define whiplash and other ligamentous injuries of the cervical spine.

Radiographic evaluation of the complications of long bone allografts

PURPOSE

To study the long-term results of long bone allografts in patients with benign and malignant bone tumors.

MATERIAL AND METHODS

Forty patients for whom full clinical and radiological information was held were investigated in order to assess the overall incidence of complications including fractures, nonunion, hardware problems, infections, and bone resorption.

RESULTS

There were four deaths; four more patients had distant metastases and one patient had a recurrent chondrosarcoma. Seventeen patients (42%) had either no complications (nine patients) or only minor ones (eight patients). Eleven patients (27%) sustained fractures of either their allograft (eight patients) or of their hardware (three patients). Hardware problems occurred in nine patients (22.5%), six of whom had serious problems requiring revision. The majority of the fractures and hardware problems occurred in younger male patients (82%). Infection occurred in five patients (12.5%), two of whom required revision, while two cases were superficial. Dissolution of the allograft occurred in 12 patients (30%), 7 of whom required removal of the allograft. Ten of these 12 patients were female.

CONCLUSION

The long-term survival of long bone allografts is not as good as generally reported if an adequate follow-up time period is used. Most of the fractures and hardware problems occurred in the younger active male patients, whose activities should probably be curtailed. Resorption of the allograft is another serious complication which appears to occur mainly in female patients and could possibly be controlled by chemotherapy.

Orthopedic complications

This overview of the complications encountered in orthopedic cases focuses on, among other things, complications of spinal surgery. The incidence of infection in spinal instrumentation and other orthopedic procedures is discussed and followed by a review of the complications of total joint replacement. Finally, a few words on the radiologist's responsibility for the reporting of orthopedic complications are given.

Total hip replacement and other orthopedic hip procedures

The history of total hip replacement including that of the Girdlestone procedure and resurfacing procedures is discussed. An overview of total hip replacement and its indications and complications forms the bulk of this section. Also, the use of porous-coated prostheses and endoprostheses as well as pins and plates is discussed and illustrated.

The radiology of bone allografts

Bone allograft surgery provides an attractive and effective solution to many orthopedic problems. Nevertheless, the entire process is technically demanding and associated with many potential complications of which infection is one of the most difficult to treat. Many advances have been made in the procurement and use of bone allografts, and further investigation should expand the applications of allograft surgery and continue to diminish the incidence of complications.

Radiologic case study. Multicentric reticulohistiocytosis

MRH is somewhat similar to, and probably occasionally mistaken for, psoriatic arthritis, Reiter's syndrome, or less frequently, rheumatoid arthritis. However, several important features distinguish MRH from the other arthritides. Rheumatoid arthritis more commonly involves the metacarpophalangeal joints, while MRH ordinarily affects the distal interphalangeal and proximal interphalangeal joints. Furthermore, MRH rarely exhibits the degree of articular osteopenia that is the hallmark of rheumatoid disease. While psoriatic arthritis and Reiter's often affect the DIP joints, they rarely display the symmetry of MRH. In addition, MRH does not demonstrate the periosteal new bone formation that is seen in both psoriatic arthritis and Reiter's syndrome. Hence, the diagnosis of MRH may be made with reasonable confidence on the radiologic findings alone, even before the cutaneous nodules appear, which can then be biopsied to confirm the diagnosis.

Diagnosis of breast implant rupture: imaging findings and relative efficacies of imaging techniques

OBJECTIVE

The purpose of this study was to compare the efficacies of mammography, sonography, CT, and MR imaging in the detection of breast implant rupture and to analyze the imaging findings.

SUBJECTS AND METHODS

Thirty-two women with 63 silicone breast implants participated in the study. All but one had signs and symptoms suggestive of rupture, and all had requested that their implants be removed before they were enrolled in this imaging study. All patients had film-screen mammography, sonography, CT, and MR imaging. Twenty-two ruptures were found at surgery; 21 were intracapsular and one was extracapsular. The relative efficacies of the imaging studies were determined, and the imaging findings were compared with the surgical results.

RESULTS

Of the 32 women with 63 implants, mammographic sensitivity for detecting implant rupture was only 23% but the specificity was 98%. Sonography had a higher sensitivity (59%), but its specificity was significantly lower (79%). CT had a sensitivity of 82% and a specificity of 88%. MR was the only imaging technique that consistently provided evidence that enabled the evaluation of intracapsular and extracapsular ruptures. The sensitivity and specificity of MR imaging were 95% and 93%, respectively.

CONCLUSION

Our results show that MR imaging is more sensitive and specific for the detection of breast implant rupture than is mammography, CT, or sonography.

Staging of musculoskeletal tumors

Staging of musculoskeletal neoplasms is important for planning chemotherapy and surgical procedures. Accurate staging has increased in importance with advancements in limb salvage procedures. This article outlines concepts, techniques, and potential problems with staging of neoplasms. It is important to remember that biopsy should be preformed after consultation with an orthopedic surgeon specialized in tumor surgery.

Radiologic case study. Macrodystrophia lipomatosa

Macrodystrophia lipomatosa is a rare form of gigantism involving an extremity consisting of predominately fibroadipose tissue. Radiographically, it appears as hypertrophy of soft tissues and bone. CT and MR scanning delineate the tissues involved and are virtually diagnostic, demonstrating the predominantly adipose component as well as the overgrowth of the bones, nerves, and vessels also involved.

Magnetic resonance imaging of the nose with surface coils: a new technique to evaluate functional and aesthetic problems

Determining the preoperative functional and aesthetic anatomy has been of critical importance to surgeons planning nasal procedures. Beyond skilled clinical examination, few objective studies exist to aid the surgeon. Magnetic resonance imaging (MRI) represents a potentially excellent method for precise anatomic imaging of the nose. Unlike computed tomography (CT) and conventional x-rays, MRI involves no radiation. Similar to CT, however, MRI can provide computer-enhanced three-dimensional and quantitative airway data. Full-head MRI has proven sensitivity in evaluation of tumors of the brain and sinuses and is the imaging modality of choice for many soft-tissue tumors. Due to the relatively high cost of conventional full-head MRI scanning ($600 to $1200 per scan), MRI of the nose utilizing full head scanning technique has been limited. The recent development of small field of view surface coils has enabled higher-resolution nasal scans at a fraction of the scanner time and cost ($200 to $500) of conventional MRI scans. We have developed a protocol utilizing a small field of view coil which results in reproducible high-resolution nasal scans requiring less than 6 minutes of scanner time. This protocol has been used in both the diagnosis and follow-up of patients with traumatic and congenital nasal and septal deformities. Image resolution obtained using the protocol is significantly better than with conventional coils. This technique is excellent for both diagnosing and documenting nasal anatomy and pathology.

Scanning electron-microscopic and magnetic resonance-imaging studies of injuries to the patellofemoral joint after acute transarticular loading

To examine the effects of transarticular loading on articular cartilage and subchondral bone, we used a canine model that we had developed previously, in which a standardized load of approximately 2000 newtons is delivered across the patellofemoral joint. The purpose of the study was to define and describe the initial changes, as seen on histopathological and magnetic resonance-imaging studies, that occur in the early stages after injury to the joint by transarticular loading. Scanning electron microscopy was used to define the extent and characteristics of the fractures produced in the subchondral bone of four patellae that were examined on the day of loading. We found multiple, extensive fractures through the zone of calcified cartilage and the subchondral bone, frequently with step-off displacement, and with little or no change in the gross appearance of the articular cartilage. Specimens from four patellae were examined histologically two weeks after loading, and the observed changes were correlated with those that had been demonstrated by scanning electron microscopy. Fractures through the zone of calcified cartilage and the subchondral bone, with step-off displacement, were prominent. Clefts were present in the surface of the articular cartilage and, in some areas, there was a focal loss of proteoglycan from the extracellular matrix, as indicated by the complete absence of staining with safranin O. Six dogs were examined one year after loading. There was healing of the subchondral fractures and restoration of proteoglycan in the extracellular matrix. However, superficial clefts and fissures were still present in the articular cartilage. Sequential magnetic resonance-imaging studies were also carried out on these six dogs, at two, eight, sixteen, thirty-six, and fifty-two weeks after loading. Two weeks after loading, all knees had soft-tissue swelling, effusion, and a decreased marrow signal in the medullary cavity of the patella. The decreased marrow signal and effusion were still present eight weeks after the impact, and then the findings gradually returned to normal. One year after loading, it was found that the histopathological changes had not been progressive; in fact, they had been ameliorated and, to some extent, reversed by repair processes. The early, severe magnetic resonance-imaging changes had also been reversed, so that this study demonstrated normal findings by one year after loading.