Trends in slipped capital femoral epiphysis: is the rate declining?

PURPOSE: Slipped capital femoral epiphysis (SCFE) is an adolescent hip condition with a high risk of complication. The purpose of this study was to evaluate trends in treatment using a prospectively collected paediatric nationally representative database. METHODS: A total of 9034 patients undergoing treatment for idiopathic SCFE were selected by querying the Healthcare Cost and Utilization Project's Kids' Inpatient Database for the years 1997, 2000, 2003, 2006, 2009 and 2012. The selected patients were separated based on operative approach and these cohorts were analyzed based on temporal and categorical differences in operative approach, patient demographics and clinical characteristics. Univariate and multivariate analyses were used when appropriate and the Mantel-Haenszel test for trend was used in temporal analysis. RESULTS: Overall SCFE procedures have decreased 27.5% (p < 0.001). Closed procedures have decreased 28.5% (p < 0.001), while open procedures have decreased 44.8% (p < 0.001). Bilateral closed procedures have increased 7.2% (p < 0.001). The ratio of open to closed procedures decreased in patients aged nine to 12 years and increased in patients aged 13 to 16 years (p < 0.001). CONCLUSION: Here we report age stratified trends in treatment for idiopathic SCFE using nationally representative data and show an overall decrease in admissions and procedures over time. LEVEL OF EVIDENCE: Level III, retrospective comparison study.

Quest for molecular graphs with maximal energy: a computer experiment.

If lambda(1), lambda(2),..., lambda(n) are the eigenvalues of a graph G, then the energy of G is defined as E(G) = the absolute value of lambda(1) + the absolute value of lambda(2) +.... + the absolute value of lambda(n). If G is a molecular graph, representing a conjugated hydrocarbon, then E(G) is closely related to the respective total pi-electron energy. It is not known which molecular graph with n vertices has maximal energy. With the exception of m = n - 1 and m = n, it is not known which molecular graph with n vertices and m edges has maximal energy. To come closer to the solution of this problem, and continuing an earlier study (J. Chem. Inf. Comput. Sci. 1999, 39, 984-996, ref 7), we performed a Monte Carlo-type construction of molecular (n,m)-graphs, recording those with the largest (not necessarily maximal possible) energy. The results of our search indicate that for even n the maximal-energy molecular graphs might be those possessing as many as possible six-membered cycles; for odd n such graphs seem to prefer both six- and five-membered cycles.

Modeling boiling points of cycloalkanes by means of iterated line graph sequences.

A class of models for predicting boiling points of cycloalkanes is put forward, based on iterated line graphs L(i), i = 1, 2,., of the molecular graph G = L(0). Let m(i) be the number of edges of L(i), i = 0, 1, 2,. The models analyzed are of the form a(0)m(i)()(0) + a(1)m(i)(1) + a(2)m(i)(2) +. + a(k)m(ik) + b. Our optimal QSPR formulas contain m(0), m(1), m(2), m(3), and/or m(4) but never m(5) and m(6). Their precision is as good as or better than the approximations recently reported by Rücker and Rücker (J. Chem. Inf. Comput. Sci. 1999, 39, 788-802).

On walks in molecular graphs.

Walks in molecular graphs and their counts for a long time have found applications in theoretical chemistry. These are based on the fact that the (i, j)-entry of the kth power of the adjacency matrix is equal to the number of walks starting at vertex i, ending at vertex j, and having length k. In recent papers (refs 13, 18, 19) the numbers of all walks of length k, called molecular walk counts, mwc(k), and their sum from k = 1 to k = n - 1, called total walk count, twc, were proposed as quantities suitable for QSPR studies and capable of measuring the complexity of organic molecules. We now establish a few general properties of mwc's and twc among which are the linear dependence between the mwc's and linear correlations between the mwc's and twc, the spectral decomposition of mwc's, and various connections between the walk counts and the eigenvalues and eigenvectors of the molecular graph. We also characterize the graphs possessing minimal and maximal walk counts.

Binary coding of Kekulé structures of catacondensed benzenoid hydrocarbons.

An algorithm is described by means of which the Kekulé structures of a catacondensed benzenoid molecule (with h hexagons) are transformed into binary codes (of length h). By this, computer-aided manipulations with, and memory-storage of Kekulé structures are much facilitated. Any Kekulé structure can easily be recovered from its binary code.

Bounds for the Randic connectivity index

For a saturated hydrocarbon with n carbon atoms and m carbon-carbon bonds and with Randic connectivity index chi, two functions, L = L(n,m) and U = U(n,m), are determined, such that L < or = chi < U. These bounds are better than those previously reported; for most chemically relevant values of n and m there exist hydrocarbons for which chi = L or chi = U.

An algorithm for the calculation of the hyper-Wiener index of benzenoid hydrocarbons

An algorithm for the calculation of the hyper-Wiener index (WW) of benzenoid hydrocarbons (both cata- and pericondensed) is described, based on the consideration of pairs of elementary cuts of the corresponding benzenoid graph B. A pair of elementary cuts partitions the vertices of B into four classes. WW is expressed as a sum of terms of the form n11n22 + n12n21, each associated with a pair of elementary cuts; nrs, r, s = 1, 2 are the numbers of vertices in the respective four classes. The algorithm proposed enables a relatively easy calculation of WW, finding expressions for WW of homologous series of benzenoid hydrocarbons, and envisaging the relations between WW and molecular structure.

The multiplicative version of the Wiener index

The classical Wiener index, W(G), is equal to the sum of the distances between all pairs of vertexes of a (molecular) graph, G. We now consider a related topological index, pi(G), equal to the product of distances between all pairs of vertexes of G. The basic properties of the pi index are established and its possible physicochemical applications examined. In the case of alkanes, pi and W are highly correlated; a slightly curvilinear correlation exists between In pi and W.

Relation between distance-based topological indices.

The pi-index of the line graph of the molecular graph of an alkane is shown to be related to the pi, Harary, and reciprocal Wiener indices of that alkane. Thus a mathematical relation between several distance-based topological indices is obtained.

[Diagnosis of acute hematogenous osteomyelitis by ultrasound in pediatric patients]. / Diagnóstico de osteomielitis aguda hematógena por ultrasonido en el paciente pediátrico.

OBJECTIVE: The objective of this study was to evaluate the efficacy of ultrasound in the diagnosis of acute hematogenous osteomyelitis of long bones in pediatric patients. PATIENTS AND METHODS: A prospective study was performed in a tertiary care pediatric hospital. During 12 months we prospectively studied 46 patients with the clinical diagnosis of acute hematogenous osteomyelitis (AHO) of long bones at the Hospital Nacional de Niños in Costa Rica. In all patients ultrasound (US) was performed within 24-36 hours of admission, before any invasive diagnosis or therapeutic procedure was begun. RESULTS: In those without US findings, but with strongly suspected (AHO), a bone scan was done. Of these patients, 26/46 (57%) was female. The mean age was 6.8 years. Sixty-five percent (30/46) had US findings compatible with AHO affecting the tibia (13), femur (11), humerus (4), and radius (2). The findings included subperiostic fluid (10), periosteal thickening (14), subperiostic abscess (6) and thickening of subcutaneous tissues (26). Patients were surgically drained and puss was obtained from the bone in all 30. Two patients with negative US, but strongly suspected AHO had a bone scan that was negative. Patients with AHO were followed with US within 5-7 days of surgery and all 30 showed marked improvement. CONCLUSIONS: In this study, US showed 100% sensitivity and specificity for the diagnosis of AHO of long bones in pediatric patients. US are a sensitive and non-invasive procedure for the diagnosis and follow-up of AOH of long bones.

Presumed ocular myasthenia and micropsia. A case report.

A 68-year-old woman presented with diplopia. Fluctuations of dysfunction of lateral rectus muscles in both eyes were detected on consecutive examinations. The diagnosis of ocular myasthenia was proposed. After the initiation of therapy, the patient complained of disturbing micropsia. The micropsia and diplopia were relieved by occlusion of one eye or by a base-out prism over one of the patient's eyeglass lenses. Mechanisms of micropsia are discussed.

Optic nerve compression by carotid arteries in low-tension glaucoma.

Low-tension glaucoma (LTG) is manifested by glaucomatous optic nerve damage and visual field loss despite normal intraocular pressure (IOP). We describe 62 patients with classical signs of LTG. Computed tomography (CT) was performed in all patients. In 56 of the patients (90.3%), pathology of the intracavernous carotid arteries adjacent to the intracranial opening of the optic canal could be demonstrated. In 28 patients (45.2%) a clear asymmetry of the optic nerve cupping was found and could be correlated with the severity of the carotid artery pathology. A control group of 24 age-matched patients included five (20.8%) with intracavernous carotid artery calcification and only one (4.2%) with intracavernous ectasia. We suggest that calcification, dilatation and ectasia of the carotid artery into the optic canal may play an important role in the pathogenesis of many cases of LTG. The close proximity of the carotid artery to the optic nerve at this location may result in compressive neuropathy with subsequent glaucomatous damage of the optic nerve head.

Suggested mechanism for acute transient myopia after sulfonamide treatment.

This report describes the occurrence of acute transient myopia in a patient treated with sulfonamide. We followed this patient by performing A-scan ultrasonographic ocular measurements documenting the anterior chamber depth, lens thickness, and axial length during the acute and convalescent periods. The outstanding feature in this case was the documented ultrasonographically significant reduction of the anterior chamber depth combined with lens thickening. This could be caused by a forward displacement of the lens as a result of allergic ciliary body edema and rotation. These changes could explain the mechanism of drug-induced transient myopia.

Orbital pseudotumor presenting as acute glaucoma with choroidal and retinal detachment.

A 68-year-old woman presented with acute visual loss, elevated intraocular pressure (IOP), and a flat anterior chamber combined with retinal and choroidal detachment. The diagnosis of orbital pseudotumor was based on the patient's poor response to conventional therapy and on computerized tomography and ultrasound findings. After treatment with oral corticosteroids, the inflammatory process, elevated IOP, and choroidal and retinal detachment resolved.

Malignant prolactinoma.

Malignant prolactinoma is a rare entity and only a few cases have been published. The diagnostic criteria and the clinical course remain unclear. We present a case of malignant prolactinoma in a woman with a 30-year duration of the disease. In the terminal stage of the disease the prolactinoma metastasized to the left eye, the prolactin level reaching 196000 mU/l. Bromocriptine in high doses was not effective. The response to pergolide was good in the first two years of treatment; thereafter an escape effect was observed. The patient died in a comatose state. A review of previously published cases follows.

Lumbar spine dimensions in paraparetic patients: a 10 year follow up study.

Lumbar spinal AP radiographs of 13 C3-T11 paraparetic patients taken at about a 10 year interval were compared. The height (H) and maximum width (W) of the interapophysolaminar spaces (IALS), the width of the vertebral bodies at their waist (V) and the relationship between them showed minimal change over the follow up period. The difference between the late and early mean IALS height values increased caudally but was statistically significant only below L5. Subjective evaluation of the consecutive x-ray films revealed few new degenerative abnormalities. It is concluded that the normal aging process, which includes horizontal spreading of the lumbar vertebral bodies and narrowing of the lumbar spinal canal, is not accelerated by paraparesis and may even be retarded by relative immobilization.

Nd:YAG laser trabeculopuncture in angle-recession glaucoma.

Nd:YAG laser trabeculopuncture (YLT) was performed in 12 eyes of 12 patients with angle-recession glaucoma. Confluent, 1-clock-hour trabeculotomy was attempted in all eyes. The calculated average laser energy was 181 +/- 86 mJ. Where possible, the midtrabecular meshwork was treated, preferably at the superior half. After a mean follow up of 12.0 +/- 5.6 months, intraocular pressure (IOP) was controlled (less than or equal to 19 mm Hg) in five eyes (41.7%). YLT was associated with blood reflux during or after treatment in all successfully treated eyes. In eyes that failed, blood reflux could be detected in only two of seven eyes (28.6%). YLT failed to control IOP in all five eyes that had angle-recession for 360 degrees. Following YLT, IOP rose in two eyes (16.6%), minimal hyphema occurred in one eye, and temporary flare and cells developed in the anterior chamber in all eyes. Six eyes (50%) required glaucoma surgery (four had trabeculectomy and two had Molteno implant surgery). We recommend YLT only for selected cases of uncontrolled angle-recession glaucoma in which at least part of the trabecular meshwork by gonioscopy appears to maintain its anatomical structure, permitting penetration into Schlemm's canal.

Identification, prevention, and treatment of silicone oil pupillary block after an inferior iridectomy.

We treated two patients in whom silicone oil pupillary block developed despite a patent inferior iridectomy. The clinical characteristics of this complication were a deep anterior chamber, specular reflexes from the iris surface, identification by biomicroscopy of aqueous trapped inferiorly in the vitreous cavity, and no convection currents in the anterior chamber. This complication may be prevented by early face-down positioning of the patient after the operation, and the avoidance of large, centrally located, inferior iridectomies. We recommend that the iridectomy be placed peripherally no larger than 2 mm and propose a new technique for breaking the silicone oil block, which was clearly successful in one of the patients.

Postoperative complications after Molteno implant surgery.

We performed Molteno implant surgery in one eye each of 41 patients with uncontrolled glaucoma. Intraocular pressure was controlled (intraocular pressure less than or equal to 18 mm Hg) in 32 eyes (78%). The mean preoperative intraocular pressure was 40 +/- 13.2 mm Hg, whereas the mean postoperative intraocular pressure was 16 +/- 6.6 mm Hg. Patients were followed up for an average of 16 months after the operation. Visual acuity was unchanged in 23 eyes (56%), improved in nine eyes (22%), and poorer in nine eyes (22%). The major complications included shallow anterior chamber and hypotony in six eyes (14.6%), vitreous hemorrhage in two eyes (4.9%), retinal detachment in one eye (2.4%), and malignant glaucoma in two eyes (4.9%). Less grave complications included hyphema in four eyes (9.8%), peripheral choroidal effusion in 15 eyes (36.6%), obstruction of the tube in six eyes (14.6%), recession of the tube into the angle in two eyes (4.9%), erosion of the tube in one eye (2.4%), and Tenon's cyst formation in three eyes (7.3%).

Vogt-Koyanagi-Harada syndrome in two siblings.

Two cases of a brother and a sister with characteristic manifestations of Vogt-Koyanagi-Harada syndrome are presented. To the best of our knowledge, this is the first report of a typical appearance of Vogt-Koyanagi-Harada syndrome in two siblings.