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Magnetic resonance images of optic nerves were obtained in 20 patients with acute optic neuritis (ON), and assessed by means of clinical, visual field and visual evoked potential evaluations; the imaging was repeated 1 year later. The results of the conventional Short Tau Inversion Recovery (STIR) sequence obtained using short time echo (STE-STIR: 22 msec) were compared with those of the long time echo sequence (LTE-STIR: 80 msec). The conventional STE-STIR sequence revealed lesions in 57.2% cases of acute ON and in 42.9% of the optic nerves affected by previous ON: the LTE-STIR sequence was diagnostic in 95.2% of acute ON cases and in 85% of patients with previous ON. The calculated length of the optic nerve lesions was significantly longer in the images obtained using the LTE-STIR sequence than in those obtained using conventional STE-STIR sequences.
Sommario Si descrivono i risultati ottenuti con indagini di Risonanza Magnetica (RM) dei nervi ottici (eseguite all'esordio e 12 mesi dopo) in 20 pazienti affetti da Neurite Ottica (NO) acuta, valutata in funzione della sintomatologia clinica e delle alterazioni campimetriche e del potenziale evocato visivo.Sono state analizzate le immagini RM in Short Tau Inversion Recovery (STIR) mettendo a confronto i rilievi ottenuti con sequenza Short Time Echo (STE-STIR: 22 msec) rispetto a quelli ottenuti con Long Time Echo (LTE-STIR: 20 msec). Mentre con la convenzionale STE-STIR è stato possibile rilevare lesioni a carico dei nervi ottici nel 57.2% delle Neuriti Acute e nel 42.9% delle Neuriti Pregresse, la metodica LTE-STIR è risultata diagnostica nel 95.2% delle Neuriti Acute e nel 85% delle Neuriti Pregresse.Sia nelle NO acute che nelle pregresse, la lunghezza delle lesioni a carico dei nervi ottici sono risultate significativamente maggiori rispetto a quelle ottenute con la convenzionale metodica STE-STIR.
  相似文献   
3.
AIM: To assess the efficacy and safety of a heavy silicone oil (Densiron 68) in the management of inferior retinal detachment recurrence. METHODS: A retrospective non-comparative consecutive case series study. Forty-nine cases of complex inferior retinal detachment were treated using Densiron 68 heavy silicone oil (HSO) as the endotamponade. Our main purpose was anatomic reattachment following Densiron 68 removal. Functional outcomes, rate of recurrences, the presence of inflammatory complications and intraocular pressure alterations were evaluated. RESULTS: Forty-nine patients affected by complex retinal re-detachment were recruited. The mean follow-up was 7.6 (±1.5) mo. The mean best corrected visual acuity after Densiron 68 removal was 0.95 logMAR, standard error (SE: 0.068). Retinal reattachment was 61.2% after first surgery and 81.6% after second surgery. Nineteen cases (38.8%) had recurrences when intraocular heavy silicon oil was in situ, 26.3% (5 cases) of which involved the inferior retina. CONCLUSION: Densiron 68 ef?ciently fills the inferior retinal periphery and might lower the risk of inferior proliferative vitreoretinopathy development, in particular after a standard silicon oil tamponade that reduces the proliferative process in the upper quadrants of the retina.  相似文献   
4.
Default mode network resting state activity in posterior cingulate cortex is abnormally reduced in Alzheimer disease (AD) patients. Fluctuating cognition and electroencephalogram abnormalities are established core and supportive elements respectively for the diagnosis of dementia with Lewy bodies (DLB). Our aim was to assess whether patients with DLB with both of these features have different default mode network patterns during resting state functional magnetic resonance imaging compared with AD. Eighteen patients with DLB, 18 AD patients without fluctuating cognition, and 15 control subjects were selected after appropriate matching and followed for 2–5 years to confirm diagnosis. Independent component analysis with functional connectivity (FC) and Granger causality approaches were applied to isolate and characterize resting state networks. FC was reduced in AD and DLB patients compared with control subjects. Posterior cingulate cortex activity was lower in AD than in control subjects and DLB patients (p < 0.05). Right hemisphere FC was reduced in DLB patients in comparison with control subjects but not in patients with AD, and was correlated with severity of fluctuations (ρ = −0.69; p < 0.01). Causal flow analysis showed differences between patients with DLB and AD and control subjects.  相似文献   
5.

Introduction

Dentofacial deformity refers to deviations from normal facial proportions and dental relationships that are severe enough to be handicapping. These anomalies involve many aspects of patient’s life and are sometimes also associated with a reduction of pharyngeal air space. Through orthognathic surgery it is possible to treat dentofacial deformities: this kind of surgery has several effects on skeletal structures and it has changes, as it is demonstrated by many studies, also on the upper airways. The orthognathic surgeries commonly used to correct this deformity are the mandibular setback and the maxillary advancement procedures. This study aims to evaluate the effects of maxillary and mandibular surgery on pharyngeal airway dimensions in skeletal class III malocclusions.

Materials and methods

This study considers 76 patients, treated between 2007 and 2013 by maxillary advancement (11 patients), maxillary advancement and mandibular setback (39 patients), maxillary advancement, mandibular setback and genioplasty reduction (26 patients). Cranial latero-lateral radiography was used to compare oropharyngeal airway morphologies before and 1 year after surgery.

Conclusion

The surgeon should consider bimaxillary surgery rather than mandibular setback surgery to correct a class III deformity to prevent the development of obstructive sleep apnea syndrome; in fact, bimaxillary surgery might have less effect on reduction of the pharyngeal airway than mandibular setback surgery only.  相似文献   
6.
Studies on the interactions between SARS-CoV-2 and humoral immunity are fundamental to elaborate effective therapies including vaccines. We used polychromatic flow cytometry, coupled with unsupervised data analysis and principal component analysis (PCA), to interrogate B cells in untreated patients with COVID-19 pneumonia. COVID-19 patients displayed normal plasma levels of the main immunoglobulin classes, of antibodies against common antigens or against antigens present in common vaccines. However, we found a decreased number of total and naïve B cells, along with decreased percentages and numbers of memory switched and unswitched B cells. On the contrary, IgM+ and IgM plasmablasts were significantly increased. In vitro cell activation revealed that B lymphocytes showed a normal proliferation index and number of dividing cells per cycle. PCA indicated that B-cell number, naive and memory B cells but not plasmablasts clustered with patients who were discharged, while plasma IgM level, C-reactive protein, D-dimer, and SOFA score with those who died. In patients with pneumonia, the derangement of the B-cell compartment could be one of the causes of the immunological failure to control SARS-Cov2, have a relevant influence on several pathways, organs and systems, and must be considered to develop vaccine strategies.  相似文献   
7.
Skin necrosis is the most severe complication arising from hyaluronic acid (HA) injection. To avoid skin necrosis, hyaluronidase should be injected along the course of the involved artery, to allow blood flow restoration. We evaluated the ability of hyaluronidase to degrade a HA filler in two simulated clinical situations—a compression case and an embolization case—to identify differences in the hyaluronidase injection. In the compression case, a bolus of HA filler was directly soaked in hyaluronidase solution; in the embolization case, a vein harvested from a living patient was filled with the same HA filler and then soaked in hyaluronidase. We then evaluated the quantity of HA remaining after 2 hr. While we found hydrolysis of HA in both cases, in the compression case, we detected almost complete hydrolysis, whereas in the embolization case we observed a reduction of the 60%. Our results support the hypothesis that vessel compression can be resolved with only one injection of hyaluronidase, while in the case of vascular embolization, repeated perivascular injections should be performed owing to the reduction of hyaluronidase activity.  相似文献   
8.
This study analyzes the efficacy of occlusal devices for the long-term stability of contouring of the lower face by injection of Botulinum toxin type A in a prospective clinical protocol. Ten patients (seven female and three male) with a widened lower face were recruited consecutively between January 2006 and January 2007. Each patient was advised to wear an occlusal device to release masticatory muscles, and percutaneous intramuscular injections of Botulinum toxin type A were used. The follow-up study was 18 months. Facial changes were noted by the patients as early as 2 weeks after the injection and lasted for 18 months; all patients reported an improved facial profile. There were no complications. Botulinum toxin type A injection for the contouring of the lower face is a simple technique, has few side effects, and allows a rapid return to daily life. In our study, the long-term stability of the result is related to the occlusal therapy performed after the injection of botulinum toxin type A.  相似文献   
9.
Functional magnetic resonance imaging (fMRI) was used to study the cortical activity of the bilateral secondary somatosensory cortex (SII) during nonpainful (motor threshold) and painful electrical stimulation of median and tibial nerves. fMRI recordings were performed in eight normal young adults. The aim was at evaluating the working hypothesis of a spatial segregation of nonpainful and painful populations not only in the "hand" representation of SII [Ferretti, A., Babiloni, C., Del Gratta, C., Caulo, M., Tartaro, A., Bonomo, L., Rossini, P.M., Romani, G.L., 2003. Functional topography of the secondary somatosensory cortex for nonpainful and painful stimuli: an fMRI study. NeuroImage 20, 1625-1638.] but also in its "foot" representation. Results showed that, in both "hand" and "foot" representations of bilateral SII, the activity elicited by the painful stimulation was localized more posteriorly with respect to that elicited by the nonpainful stimulation. A fine spatial analysis of the SII responses revealed a clear somatotopic organization in the bilateral SII subregion especially reactive to the nonpainful stimuli (i.e., segregation of the hand and foot representations). In contrast, it was not possible to disentangle the "hand" and "foot" representations of SII for painful stimuli. These results extended to the SII "foot" representation previous evidence of a spatial segregation in the SII "hand" representation of subregions for the painful and nonpainful stimuli. Furthermore, they suggest that noxious information is not somatotopically represented in human bilateral SII, at least as inferred from fMRI data at 1.5 T.  相似文献   
10.
The aim of the present pilot study was to compare the efficacy and safety of trimethoprim (TMP) and sulfamethoxazole (SMX) with those of the standard therapy pyrimethamine (P)-sulfadiazine (S) for the treatment of toxoplasmic encephalitis in patients with AIDS. This was a pilot, multicenter, randomized, and prospective study. Patients were randomly assigned to receive TMP (10 mg/kg of body weight/day) and SMX (50 mg/kg/day) or P (50 mg daily) and S (60 mg/kg/day) as acute therapy (for 4 weeks) and then as maintenance therapy for 3 months at half of the original dosage. Seventy-seven patients were enrolled and randomized to the study: 40 patients were treated with TMP-SMX and 37 were treated with P-S. There was no statistically significant difference in clinical efficacy during acute therapy. In contrast, patients randomized to TMP-SMX appeared more likely to achieve a complete radiologic response after acute therapy. Adverse reactions were significantly more frequent in patients treated with P-S, and skin rash was the most common adverse event noted in these patients. In conclusion, the results of the study suggest that TMP-SMX appears to be a valuable alternative to P-S, in particular in patients with opportunistic bacterial infections.  相似文献   
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