Surgery of vestibular schwannomas: an institutional experience.

Aims: To report management results of vestibular schwannomas (VS) treated surgically in our institute, with particular reference to completeness of tumor excision, facial nerve and hearing preservation and complications of surgery.

Study Design And Settings: Retrospective study of 259 patients treated during the years 1988 to 2002.

Materials And Methods: The facial nerve function and hearing assessment was done according to House-Brackmann [HB] grading and pure tone audiometry (PTA) respectively.

Surgical outcome in rheumatoid Ranawat Class IIIb myelopathy.

Objective: Rheumatoid arthritis frequently affects the craniovertebral junction (CVJ) and may lead to severe neck pain, quadriparesis, and respiratory dysfunction. Surgery in rheumatoid nonambulatory (Ranawat Class IIIb) patients carries a significant risk. This study presents the surgical outcome of Class IIIb patients with CVJ rheumatoid myelopathy and reviews the literature.

First measurements of inclusive W and Z cross sections from run II of the fermilab tevatron collider.

We report the first measurements of inclusive W and Z cross sections times leptonic branching ratios for pp collisions at square root[s]=1.96 TeV, based on their decays to electrons and muons. The data correspond to an integrated luminosity of 72 pb(-1) recorded with the CDF detector at the Fermilab Tevatron.

Measurement of Wgamma and Zgamma production in pp collisions at square root s=1.96 TeV.

The standard model predictions for Wgamma and Zgamma production are tested using an integrated luminosity of 200 pb(-1) of pp collision data collected at the Collider Detector at Fermilab. The cross sections are measured by selecting leptonic decays of the W and Z bosons, and photons with transverse energy ET>7 GeV that are well separated from leptons. The production cross sections and kinematic distributions for the Wgamma and Zgamma data are compared to SM predictions.

Measurement of the lifetime difference between Bs mass eigenstates.

We present measurements of the lifetimes and polarization amplitudes for B(0)(s)-->J/psiphi and B(0)(d)-->J/psiK(*0) decays. Lifetimes of the heavy and light mass eigenstates in the B(0)(s) system are separately measured for the first time by determining the relative contributions of amplitudes with definite CP as a function of the decay time. Using 203+/-15 B(0)(s) decays we obtain tau(L) = (1.

Search for excited and exotic electrons in the egamma decay channel in pp collisions at sqrt[s] = 1.96 TeV.

We present a search for excited and exotic electrons (e(*)) decaying to an electron and a photon, both with high transverse momentum. We use 202 pb(-1) of data collected in pp collisions at sqrt[s] = 1.96 TeV with the Collider Detector at Fermilab II detector.

Atlantoaxial dislocation associated with the maldevelopment of the posterior neural arch of axis causing compressive myelopathy.

The craniovertebral junction has a predilection for a variety of congenital anomalies due to its complex development. The association of atlantoaxial dislocation (AAD) with the maldevelopment of the posterior arch of axis is extremely rare. We report two such cases and present the management strategy.

Factors influencing the outcome in symptomatic Chiari I malformation.

Background: To study the clinico-radiological determinants of outcome in patients with Chiari I malformation (CIM).

Materials And Methods: The disability assessment of 48 patients with C I M who underwent posterior decompression was done by modified Klekamp and Samii scoring system. The outcome was regarded as good when the patient was ambulant without any aid with an improvement in the disability score; and, poor when (a) there was postoperative deterioration or lack of improvement; (b) the patient was non-ambulant without aid, irrespective of the improvement in the clinical score; or, (c) there was a perioperative mortality.

Search for doubly charged Higgs bosons decaying to dileptons in pp collisions at square root of s=1.96 TeV.

We present the results of a search for doubly charged Higgs bosons (H+/-+/-) decaying to dileptons (ll(')) using approximately 240 pb(-1) of pp collision data collected by the CDF II experiment at the Fermilab Tevatron. In our search region, given by same-sign ll(') mass m(ll('))>80 GeV/c(2) (100 GeV/c(2) for ee channel), we observe no evidence for H+/-+/- production. We set limits on sigma(pp -->H++H---->l(+)l('+)l(-)l('-)) as a function of the mass of the H+/-+/- and the chirality of its couplings.

Measurement of the tt production cross section in pp collisions at sqrt[s]=1.96 TeV using dilepton events.

We report a measurement of the tt production cross section using dilepton events with jets and missing transverse energy in pp collisions at a center-of-mass energy of 1.96 TeV. Using a 197+/-12 pb(-1) data sample recorded by the upgraded Collider Detector at Fermilab, we use two complementary techniques to select candidate events.

Inclusive double-pomeron exchange at the fermilab tevatron p p collider.

We report results from a study of events with a double-Pomeron exchange topology produced in p p collisions at sqrt[s]=1800 GeV. The events are characterized by a leading antiproton and a large rapidity gap on the outgoing proton side. We find that the differential production cross section agrees in shape with predictions based on Regge theory and factorization, and that the ratio of double-Pomeron exchange to single diffractive production rates is relatively unsuppressed as compared to the O(10) suppression factor previously measured in single diffractive production.

Solitary Langerhans-cell histiocytosis of the clivus and sphenoid sinus with parasellar and petrous extensions: case report and a review of literature.

Background: In Langerhans-cell histiocytosis, there occurs an uncontrolled clonal proliferation of dendritic cells that have Langerhans cell like characteristics. In this report, a unique case of a solitary, skull base Langerhans-cell histiocytosis (LCH) is described.

Case Description: A 15-year-old boy presented with raised intracranial pressure, decreased visual acuity, bilateral abducent nerve palsy, and 25% hypoesthesia in all three divisions of the right trigeminal nerve.

Surgical approach to C1-C2 nerve sheath tumors.

Background: C1 and C2 nerve sheath tumors (NST) are unique in presentation, relationship to neighbouring structures and surgical approaches when compared to their counterparts in other regions of the spine.

Aim: The strategies involved in the surgery for C1-C2 NST are discussed

Setting And Design: Retrospective study.

Methods: 21 patients with C1 (n=6) and C2 (n=15) NST were operated based on their position with respect to the cord i.

Observation of the narrow state X(3872)-->J/psipi+pi- in pp collisions at sqaure root of s=1.96 TeV.

We report the observation of a narrow state decaying into J/psipi+pi- and produced in 220 pb(-1) of p p-bar collisions at =1.96 Tesqaure root of sV in the CDF II experiment. We observe 730+/-90 decays.

Search for B0s-->micro+micro- and B0d-->micro+micro- decays in pp collisions at square root s = 1.96 TeV.

We report on a search for B(0)(s)-->micro(+)micro(-) and B(0)(d)-->micro(+)micro(-) decays in pp collisions at square root of s=1.96 TeV using 171 pb(-1) of data collected by the CDF II experiment at the Fermilab Tevatron Collider. The decay rates of these rare processes are sensitive to contributions from physics beyond the standard model.

Inclusive search for anomalous production of high-pT like-sign lepton pairs in pp collisions at square root s = 1.8 TeV.

We report on a search for anomalous production of events with at least two charged, isolated, like-sign leptons, each with pT > 11 GeV/c using a 107 pb(-1) sample of 1.8 TeV pp collisions collected by the CDF detector. We define a signal region containing low background from standard model processes.

C3-4 level cervical spondylotic myelopathy.

Cervical spondylotic myelopathy (CSM) is uncommon at the C3-4 level. Fourteen patients with C3-4 CSM were treated over a period of 3 years. The radiological factors contributing to CSM at the C3-4 level were studied.

Role of diffusion-weighted imaging and in vivo proton magnetic resonance spectroscopy in the differential diagnosis of ring-enhancing intracranial cystic mass lesions.

Objectives: Proton magnetic resonance spectroscopy (PMRS) and diffusion-weighted imaging (DWI) were compared to determine which technique is more effective in the differential diagnosis of cystic intraparenchymal ring-enhancing lesions with variable perifocal edema.

Methods: Fifty-two patients (abscesses [n = 29], tumor cysts [n = 20], and benign cysts [n = 3]) formed the basis for comparative evaluation in this study. The criteria for abscess diagnosis were apparent diffusion coefficient (ADC) values less than 0.

Association between an aplastic basilar artery, unaccompanied by a primitive carotid-vertebrobasilar anastomosis, and multiple aneurysms on the dominant posterior communicating artery.

Basilar artery (BA) aplasia when unaccompanied by a primitive carotid-vertebrobasilar anastomosis is exceedingly rare. The association of BA aplasia with two aneurysms on the dominant posterior communicating artery (PCoA) has not been previously reported. This 40-year-old man presented in a state of drowsiness and responded to simple commands only after being coaxed.

Search for Kaluza-Klein graviton emission in pp collisions at square root[s] = 1.8 TeV using the missing energy signature.

We report on a search for direct Kaluza-Klein graviton production in a data sample of 84 pb(-1) of ppmacr; collisions at sqrt[s]=1.8 TeV, recorded by the Collider Detector at Fermilab. We investigate the final state of large missing transverse energy and one or two high energy jets.

Search for pair production of scalar top quarks in R-parity violating decay modes in pp collisions at square root of s=1.8 TeV.

We present the results of a search for pair production of scalar top quarks (t(1)) in an R-parity violating supersymmetry scenario in 106 pb(-1) of pp collisions at square root of s=1.8 TeV collected by the Collider Detector at Fermilab. In this mode each t(1) decays into a tau lepton and a b quark.

Chiari I malformation related syringomyelia: radionuclide cisternography as a predictor of outcome.

Background: This prospective study, conducted in patients with Chiari I malformation (C I) related syringomyelia who underwent posterior decompression and duroplasty, utilizes radionuclide cisternography in order to study the cerebrospinal fluid (CSF) dynamics at the foramen magnum and to predict the clinical outcome following surgery.

Methods: 17 consecutive patients of C I with syringomyelia (but without hydrocephalus or fixed atlanto-axial dislocation), underwent a detailed neurological examination and were assigned a clinical disability score based on the modified Klekamp and Samii score. A radionuclide cisternography (using Tc99m-DTPA) was performed via the lumbar route and the ascent of the tracer was followed utilizing a gamma camera immediately after injection and then sequentially after 1, 2, 4, 6 and 24 hours.

Measurement of prompt charm meson production cross sections in pp collisions at square root s = 1.96 TeV.

We report on measurements of differential cross sections dsigma/dp(T) for prompt charm meson production in ppmacr; collisions at sqrt[s]=1.96 TeV using 5.8+/-0.

Search for lepton flavor violating decays of a heavy neutral particle in p(-)p collisions at sqrt[s]=1.8 TeV.

We report on a search for a high mass, narrow width particle that decays directly to emu, etau, or microtau. We use approximately 110 pb(-1) of data collected with the Collider Detector at Fermilab from 1992 to 1995. No evidence of lepton flavor violating decays is found.

Congenital absence of the posterior elements of C2 vertebra: a case report.

A rare case of the complete absence of the posterior elements of C2 is reported. The patient presented with neck pain without any neurological deficits and radiology revealed a mobile, partially reducible dislocation of the C2 over C3 vertebra. A posterior fusion utilizing a contour rod, sublaminar wire fixation, and onlay bone grafts between the occiput and the C3 vertebra was performed for spinal stability.