Application of intravoxel incoherent motion (IVIM) magnetic resonance imaging in the evaluation of primitive brain tumours.

Intravoxel incoherent motion is a potential non-invasive diagnostic tool in brain tumours, without any clear guidelines for its evaluation yet. In our study, we compare intravoxel incoherent motion with dynamic susceptibility contrast magnetic resonance imaging in the quantification of tumour tissue blood perfusion in 28 patients affected by brain tumours, highlighting the issues encountered during the acquisition set-up and post-processing steps. Intravoxel incoherent motion is a new imaging tool and an alternative technique to dynamic susceptibility contrast-magnetic resonance imaging which is of considerable interest at present. This is partly because it does not require the use of a contrast agent and relies on the intrinsic properties of motion in the capillaries of the spins. Compared to dynamic susceptibility contrast-magnetic resonance imaging, the intravoxel incoherent motion technique is also characterised by better resolution because the gadolinium-based contrast agent bolus used in the standard technique results in a variation by more than 50% of the signal coming from the brain. Finally, intravoxel incoherent motion is more sensitive to the incoherent motion that originates from small capillary vessels, while the dynamic susceptibility contrast signal is also contaminated by the input from larger arteries and veins, which may result in an overestimation of the blood volume. Although there are limitations due to the heterogeneity of the sample considered in our study, intravoxel incoherent motion has been shown to be an accurate noninvasive radiological biomarker, useful to distinguish between low and high grade glial tumours.

Basaloid squamous cell carcinoma of the larynx: report of a early laryngeal cancer.

Basaloid squamous cell carcinoma is a recently recognized, rare and aggressive variant of squamous cell carcinoma with a predilection to occur in base of the tongue, hypopharynx and larynx (especially the supraglottic tract). It is usually diagnosed in advanced stage, frequently with distant metastases, requiring aggressive surgical intervention. The prognosis is remarkably poor even after the association of radiotherapy or chemotherapy. Nevertheless recently it has been reported that in the early stage this neoplasm seems to have a behaviour less aggressive, similar to conventional squamous carcinoma. The therapeutic approach is not clearly defined when the neoplasm is diagnosed at an early stage. We present a case of early stage of basaloid squamous cell carcinoma of the supraglottic larynx.

Adeno-tonsillar surgery in Italy.

Indications to surgery for adeno-tonsillar inflammatory disorders and analysis of the effectiveness of surgical treatment, compared with watchful waiting strategy, continue to be the subject of scientific debate. The present investigation focuses on the surgical activity of 14 Italian Otorhinolaryngological Units between 1999 and 2004. Surgical interventions (adeno-tonsillectomy, adenoidectomy, tonsillectomy) on 26915 children (age range: 2-11 years) were considered. Data on adeno-tonsillar interventions were analysed in relation to other interventions of ENT interest, performed in the same units and in the same period. Adeno-tonsillar interventions accounted for 35.4% of all operations of ENT interest. Adeno-tonsillectomy accounted for 56.6% of overall adeno-tonsillar operations, adenoidectomy 31.6%, tonsillectomy 11.8%. The percentage for the three interventions was homogeneous in the period of the study and in the recruited units. The percentage of children who underwent adeno-tonsillar surgery in paediatric units was higher as compared to general units, as far as concerns the overall number of operations performed. In southern Italy, the number of adeno-tonsillar interventions, in general, and of adeno-tonsillectomy, in particular, was higher compared to that in northern Italy. Results of the present study suggest that environmental factors, cultural issues and local health demands, may influence indications and, therefore, the different incidence of the operations under consideration in the units taking part in the investigation.

A rare case of adenoid cystic carcinoma of the nasopharynx manifesting as Horner's syndrome: discussion and review of the literature.

Adenoid cystic carcinoma is a malignant tumour involving the salivary glands, rarely developing in the nasopharynx. The biological behaviour of adenoid cystic carcinoma is characterized by slow growth rate, high tendency to local recurrence and metastatic spread. Its histological features are particularly important for prognostic prediction: solid pattern has the worst outcome. Initial presentation of nasopharyngeal adenoid cystic carcinoma with paresis of cranial nerves and Horner's syndrome is infrequent. The Authors present a case of a rare adenoid cystic carcinoma of the nasopharynx, at admission with Horner's syndrome, in a 66-year-old male. Magnetic resonance imaging showed an expansive submucosal lesion of the nasopharynx involving the para-pharyngeal space, tensor and levator veli palati muscles and the apex of petrous bone. Positron emission tomography excluded distant metastasis. Definitive histopathological examination revealed an adenoid cystic carcinoma with mixed cribriform and solid pattern. The patient was treated exclusively with radiotherapy (70 Gy) in 35 fractions with partial reduction of the neoplastic mass.

Trans-tracheostomic endoscopy of the larynx in the evaluation of dysphagia.

Laryngeal endoscopy plays a determinant role in clinical evaluation of dysphagia. The examination is performed by means of a trans-nasal approach with a flexible fiberoptic endoscope, able to visualize the pre- and post-deglutitory steps of the pharyngeal phase of swallowing. In patients with tracheostomy, it is possible to visualize the glottic or neoglottic function during the intra-deglutitory phase, performing the examination through a trans-tracheostomic route. The procedure and indications of this endoscopic technique are described.

Surgical rehabilitation of dysphagia after partial laryngectomy.

Surgical rehabilitation of dysphagia in patients who have undergone partial laryngectomy is aimed at improving the sphincteric action of the larynx, the anatomy and physiology of which are impaired. The interventions indicated for this purpose can be performed either with an external or endoscopic approach. The Authors present early results of their experience employing injection laryngoplasty with autologous fat, bovine collagen (Zyplast, McGhan Medical Corporation, Fremont, CA, USA) and PDMS (Vox Implants, Uroplasty Inc, Minnetonka, MN, USA), performed by means of fiberendoscopy, under local anaesthesia, and microlaryngoscopy, under general anaesthesia.

Clinical non-instrumental evaluation of dysphagia.

Clinical non-instrumental evaluation plays an important role in the assessment of the dysphagic patient. This evaluation, called "bedside examination", aims to establish whether dysphagia is present, evaluating severity, determining the alterations which cause it, planning rehabilitation, testing outcome of treatment. The assessment takes into consideration anamnesis regarding the swallowing problem, evaluation of the anatomy and functionality, of sensitivity and the reflexes, of the swallowing apparatus. Finally, the oral feeding test is performed, which evaluates the oral and pharyngeal phases of swallowing. The examination performed in the neurologic patient is different from that performed in the patient submitted to ENT or maxillo-facial surgery.

Preliminary clinical experience with intraoperative stereotactic ultrasound imaging.

Neurosurgery guided by intraoperative ultrasound imaging is presented. The method is based on a stereotactic handfree ultrasound imaging device, designed to monitor cerebral shifts and lesion volume modifications during surgery. Preoperative CT and MR, acquired within a reference system, merge with ultrasound images stereotactically obtained by means of a lockable articulated encoded support. Landmarks from the lesion and surrounding structures are identified prior to opening of the dura and used during surgery to monitor volume changes.

Clinical applications of an ATM/Ethernet network in departments of neuroradiology and radiotherapy.

An integrated system for the multimedia management of images and clinical information has been developed at the Isituto Nazionale Neurologico C. Besta in Milan. The Institute physicians have the daily need of consulting images coming from various modalities. The high volume of archived material and the need of retrieving and displaying new and past images and clinical information has motivated the development of a Picture Archiving and Communication System (PACS) for the automatic management of images and clinical data, related not only to the Radiology Department, but also to the Radiotherapy Department for 3D virtual simulation, to remote teleconsulting, and in the following to all the wards, ambulatories and labs.

[Stereotactic radiotherapy with linear accelerators. Dosage considerations on collimators and photon beam energy]. / La radioterapia stereotassica con acceleratori lineari. Considerazioni dosimetriche sui collimatori e sull'energia di fasci di fotoni.

The small X-ray beam profiles produced by linear accelerators and used in stereotactic radiosurgery were studied. Circular focusing and not-focusing beams outlined by additional collimators (diameter ranging 10 to 30 mm) and square field outlined by the jaws (field size 10 to 30 mm) were measured. 6 and 18-MV X-ray beams from a dual energy accelerator and 6 and 15-MV X-ray beams produced by 2 single-energy accelerators were used. Measurements were carried out with Kodak X Omat V films in a perspex phantom in the same conditions for all the fields. To study the profile characteristics we introduced the V80/V20 = (R80/R20)3 ratio where R80 and R20 are respectively the mean distance of the 80% and 20% isodose lines from the beams axis. Measurement results show that 6-MV X-ray beams have a higher V80/V20 ratio than the ones obtained with the other energies. There is no significant difference between the beams produced with focused collimators and those produced with not-focused collimators. Square fields outlined by the jaws have a V80/V20 ratio greatly dependent on the accelerator used. This ratio is generally worse than the ones obtained with beams outlined by additional collimators.

Robot-assisted microscope for neurosurgery.

We describe the implementation of a robotic arm connected to a neurosurgical operative microscope. A force feedback sensor drives the motors of the arm in response to the positioning of the microscope by the surgeon. Computer graphic techniques allow tracking of the current position of the microscope within the volumetric reconstruction of the brain. The integration of the prototype into the neurosurgical operating room is currently being evaluated. Preliminary comments on this experimental phase are offered.

A computer assisted toolholder to guide surgery in stereotactic space.

A computer assisted toolholder, integrated with an anatomical graphic 3-D rendering programme, is presented. Stereotactic neuroanatomical images are acquired, and the same reference system is employed to represent the position of the toolholder on the monitor. The surgeon can check the orientation of different approach trajectories, moving the toolholder in a situation of virtual reality. Angular values expressed by high precision encoders on the five joints of the toolholder modify "on line" the representation of the configuration of the toolholder within the three dimensional representation of the patient's anatomy.

A computer controlled stereotactic arm: virtual reality in neurosurgical procedures.

A computer controlled mechanical arm for stereotaxy is presented. It has 5 free joints and can be attached to a stereotactic frame. High precision digital encoders register the angular position of each joint and the computer determines the position of the tip of the instrument in the stereotactic space. Accuracy and usefulness are discussed.

Carcinoid tumours of the larynx: report of two cases.

Carcinoid tumour of the larynx is extremely rare. The increasing number of these lesions reported is due to the application of ultrastructural and immunological methods in the diagnosis. Two new cases of this malignant neoplasm are presented and discussed with particular reference to the difficulty in distinguishing carcinoids from other tumours of the larynx. The accurate pathological identification of the tumour is essential for treatment and prognosis.

Guided microsurgery by computer-assisted three-dimensional analysis of neuroanatomical data stereotactically acquired.

Stereotactic acquisition of neuroradiological data, followed by identification of cerebral structures and three-dimensional rendering, has been successfully applied to guided microsurgical resection of deep-seated cerebral lesions. The method described utilizes data from magnetic resonance, computed tomography, and digital angiography and allows the surgeon to 'wire frame' the lesion volume and the position of cerebral vessels and structures of high functional relevance. Three-dimensional rendering of surgical instrumentation around the reconstructed anatomy allows for planning and simulation of the trajectory of approach.

[Role fo ultrasound in the study of latero-cervical metastases]. / Ruolo dell'ecografia nello studio delle metastasi laterocervicali.

In patients undergoing radiotherapy (RT) for malignant neoplasies of the head and neck the availability of a diagnostic method permitting frequent, easy checkups of the latero-cervical lymph nodes would be extremely useful. This is especially so because clinical examination is often hindered by the post-actinic fibrosis of the tissues. Among the methods presently available for this purpose (CAT, NMR, lymphoscintigraphy, xerography, ultrasound) echotomography appears to be the most indicated as it is least invasive, can easily be repeated and is not difficult to perform. The refining of ultrasound techniques would, as reported in the literature, make it possible today to evaluate the effects of RT on latero-cervical metastases both during and some time after treatment. The authors, therefore evaluated the advantages and limitations of the method examining 33 patients undergoing RT for latero-cervical metastases due to head and neck carcinoma. Each patient underwent ultrasound examination prior to, during and at the end of the RT treatment cycle. Once treatment had been terminated 18 underwent latero-cervical neck dissection. Upon termination of the radiation treatment three distinct types of ultrasound behaviour were identified: complete response; partial response; minimal or negligible response. For those patients undergoing surgery this response was compared to lymph node chain histology while, for the others, it was compared to the ultrasound findings of subsequent examinations. The results obtained appear to indicate that a systematic scheduling of ultrasound checkups offers a reliable evaluation of how metastatic adenopathies respond to RT. At times such response can only be completed several months after treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Computer assisted analysis of neuroradiological data in planning neurosurgical procedures.

A surgical graphic console is presented. It allows the display of multimodal images (CT, MR and digital angiography), and the identification of tridimensional outlines of structures of surgical relevance, within a surgical reference system, together with the trajectory of surgical approach.