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Twelve children of age ranged from 4 to 34 months with Haemophilus influenzae type b meningitis treated at Meyer Hospital of Florence, were retrospectively reviewed. Eight patients had subdural effusion demonstrated with TC, RM and transfontanellar ultrasonography. All patients are cured without sequelae.

The authors wanted to verify the possibility of discovering, by means of transesophageal echocardiography, cardiac causes that can't be clearly shown with 2D echocardiography, in patients who suffered a cerebral ischaemic pathology and who had a cronic atrial fibrillation. The left atrial appendage is not well visualized by the 2D echocardiographic approach. Transesophageal echocardiography has been shown to be superior to transthoracic imaging in the evaluation of the mass lesions in the left atrium and his appendage and often the best visualization of the mitral valve leaflets and aortic semilunar cusps.

The principles of US physics and technology hampering both the production of US images of the bone and the assessment of the soft tissue structures underlying it are discussed. In theory, two US parameters play a role in this field: the different transmission velocity of the US beam through soft tissues and bone, and the marked attenuation of the US beam when crossing the bone. The former parameter, due to higher density and lower compressibility of the bone with respect to soft tissues, causes both intense reflection (and thus beam weakening) and refraction (and thus lateral resolution and US image distortions) at the soft tissue/bone interfaces. Moreover, US transmission velocity in the bone differs significantly from the reference velocity of the US scanners on the market based on that of soft tissues. As a consequence, during the reconstruction of a bone US image, artifacts resulting in the axial compression of bone structures should, at least in theory, occur. The latter parameter, due to both conversion into heat (absorption) and local dispersion (scattering), is likely to be main factor causing the loss of US energy when the US beam passes through the bone. Although the amount of matter (bone mass or density) undoubtedly accounts for some attenuation, local bone architecture (bulk and shear moduli of bone and marrow, bone and marrow density, marrow viscosity and porosity, permeability and tortuosity of cancellous bone structure) seems nevertheless also responsible for some attenuation through both absorption and scattering. Other consequences of attenuation reflecting on US imaging of the bone are: marked lowering of central transducer frequency and US beam widening preventing the correct identification of the interfaces originating echoes by relating them to the structures on the transducer axis. In conclusion, based on the above parameters, echoencephalography and transcranial Doppler US can be expected to improve, in the near future, their bone-crossing capabilities, even though no true gray-scale bone sonogram will ever be feasible.

The concept of death has undergone many changes in the centuries depending on ages and social contexts. However death has always been identified by heart and respiratory irreversible arrest. In the last 30 years this concept has been suddenly and deeply modified by cardiocirculatory and respiratory support techniques. The real boundary between life and death is cerebral activity. When this latter causes the subject can be considered dead. In the large majority of cases the clinical and this strumental neurological findings are sufficient for the diagnosis of brain death. However in many other cases this diagnosis may be difficult because of problems in the ascertainment of the complete and irreversible lack of cerebral activities. In these cases many an strumental techniques (evoked potentials, Doppler and nuclear medicine studies) can help in the diagnosis.

In this study, 40 patients who underwent surgery for cerebro-vascular insufficiency were considered. Carotid endarterectomy was the procedure of choice in all of the patients; the arteriotomy was always closed using a PUR patch, a new material that, for its chemical and physical characteristics seems to be a good alternative to PTFE. All of the patients underwent surgery under loco-regional anesthesia, allowing a perioperative monitoring of the neurological status through the patient's active collaboration. During the postoperative period, non local or systemic pathology related to the use of the patch has been observed. During the short and half term follow-up, the patients underwent echo-Doppler of the supra-aortic trunks that didn't show either false aneurysms or thrombosis on the patch surface.

The delay in the diagnosis of brain death represents a cause of deficiency of organs for transplant. In this prospective study we evaluate the role of Doppler sonography, to investigate typical velocimetric profiles of brain death, and to evaluate the delay between finding the typical profiles and diagnosis expressed according to law. In this ongoing study, we evaluated 32 patients affected from serious primitive intracranial diseases (Glasgow Coma Scale < or = 7). Of the 32 patients examined, 18 underwent or still remained in brain death. All the patients showed typical profiles, classified in 3 fundamental types. Start of monitoring, according to the current law, showed a delay from 12 to 27 hours. The authors conclude that Transcranial Doppler and Doppler c.w. represent an early and sensitive technique, rightly to include in the procedure of the diagnosis of brain death.

Congenital cytomegalovirus infection occurs in about 1% of live births. Although 10% of these develop severe central nervous system impairment, the remainder have asymptomatic infection. However among the asymptomatic, 10% have some problems, mainly neurosensory hearing loss. The case of an infant affected by cytomegalovirus infection who developed neurological signs and impairment in auditory brain stem response is described.

A case of cerebral angioma: non-invasive assessments. A 65-year-old woman, suffering from epileptic seizures since the age of 6, was examined. Transcranial Doppler (TCD) ultrasounds, SEPs and EEG brain mapping by means of median nerve stimulation, were performed, followed by a NMR of the brain, which revealed an arteriovenous malformation in the left hemisphere (frontal and parietal lobe). By comparing the results of the neurophysiological tests, the diagnostic value of TCD, confirmed by the neuroradiologic findings, was established. EEG and SEPs were also abnormal, but their actual effectiveness in clinical studies is discussed. We conclude that these electrophysiological examinations do not allow a reliable diagnosis as with TCD.

Surgical closure of patent ductus arteriosus (PDA) and perioperative time have been proposed as conditions of increased risk of peri-intraventricular hemorrhage (PVH-IVH) in preterm infants. We examined by pre- and postoperative ultrasound (US) scan 15 low birth-weight neonates who underwent PDA ligation within the first two weeks of life. They were assessed with regard to clinical state, perioperative management and development of PVH-IVH. Fourteen did not show onset or extension of intracranial hemorrhage in the immediate postoperative period. One patient developed a wide III grade IVH in the 24 perioperative hours. His conditions were particularly severe, suggesting that many factors such as acidosis, hypoxia, hypercapnia and hypotension might have combined to lead to hemorrhage. We conclude that PDA ligation is not likely to increase the risk of PVH-IVH per se.

Describing a case of acute ischemic stroke in the middle cerebral territory, seen on CT scan, the Authors discuss the TCD results.

Congenital familial myasthenia occurred in two male brothers, born from non affected mother. The diagnosis was based on anamnestic and clinical data, on electromyographic features, and on the effect of specific therapy. The differential diagnosis and the classification of congenital familial myasthenia are discussed. This type of disease represent 1% of all cases of myasthenia, but--excluding the "transferred" myasthenia to the newborn by affected mother--the percentage raises to 3--4%. The possibility of identifying two distinct formes of familial myasthenia is emphasized, the first with "early onset" where the symptoms become evident before two years of age, the second "late onset" clinically evident later in life seems doubtful that the two forms of the disease might be due to the same underlying pathological condition.