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Montages are logical, orderly arrangements of electroencephalographic derivations or channels that are created to display activity over the entire head and to provide lateralizing and localizing information. Most often, bipolar and referential montages are used for routine electroencephalographic recordings. Common average and Laplacian montages can also be helpful in some situations. Because each type of montage has certain strengths and limitations, the ACNS guidelines recommend the use of multiple classes of montages for each electroencephalographic recording. A variety of factors need to be considered for localization by scalp electroencephalogram, but in clinical practice, a three-step approach can be used to localize an interictal epileptiform discharge by visual inspection using a standard set of scalp electrodes and conventional montages. The ACNS guideline provides a number of standard and suggested montages, but, depending on the clinical situation, additional montages can be designed using the electrodes within the 10-20 system or by placing additional electrodes.

To better understand head injuries, human head finite element (FE) models have been reported in the literature. In scenarios where the head is directly impacted and measurements of head accelerations are not available, a high-quality skull model, as well as a high-quality brain model, is needed to predict the effect of impact on the brain through the skull. Furthermore, predicting cranial bone fractures requires comprehensively validated skull models. Lastly, high-quality meshes for both the skull and brain are needed for accurate strain/stress predictions across the entire head. Hence, we adopted a multi-block approach to develop hexahedral meshes for the brain, skull, and scalp simultaneously, a first approach in its kind. We then validated our model against experimental data of brain pressures (Nahum et al., 1977 ) and comprehensive skull responses (Yoganandan et al., 1995 , Yoganandan et al., 2004 , and Raymond et al., 2009 ). We concluded that a human head FE model was developed with capabilities to predict blunt- and ballistic-impact-induced skull fractures and pressure-related brain injuries.

Background This study aims at identifying orthodontic activities with the highest frequency of unfavorable/awkward and static postures held over a period of more than 4 s based on kinematic analysis. Moreover, a separate analysis of static postures for orthodontic and non-orthodontic activities serves to evaluate the duration for which these particular postures are assumed. Methods In total, 21 (13f/8 m) orthodontists (age: 31.5 ± 3.8 years) participated in this study. CUELA, a personal measurement system, was used to collect kinematic data for all orthodontic activities in a working day. Angle values of the head and torso were evaluated in accordance with ergonomic standards. Only those postures that were held statically for 4 s and longer were selected for further analysis. Alongside the kinematic analysis, the activities performed on-site were also subject to a detailed computerized analysis. The synchronization of data collected from both measurements arranges the patterns of posture found chronologically and in conjunction with the orthodontic activities performed ((I) “treatment” (II) “office” and (III) “other activities”). Results For (I) we observed an anterior inclination of the head and torso area as well as a twist of the head and neck area to the right. We found anterior back inclination and lateral back torsion to the right for (II) and (III). If, furthermore, we differentiate the duration of static postures, there are primarily short to medium-term (4–30s) static postures identified for (I). Also, categories (II) and (III) predominantly demonstrate static back postures with a duration of up to 30 s. With regard to (II) we observed that the back is ventrally inclined for 10.1% of the total activity duration. Conclusions During treatment static strains are observed in the entire head and torso area. On the contrary, static postures prevalent in the torso area are essential for activities of the other categories, particularly office work. These findings allow for a careful selection of unfavorable and static postures for each of the activities performed and help to develop specific preventive measures.

[EN] Synthetic computed tomography (CT) images derived from magnetic resonance images (MRI) are of interest for radiotherapy planning and positron emission tomography (PET) attenuation correction. In recent years, deep learning implementations have demonstrated improvement over atlasbased and segmentation-based methods. Nevertheless, several open questions remain to be addressed, such as which is the best of MRI sequences and neural network architectures. In this work, we compared the performance of different combinations of two common MRI sequences (T1- and T2-weighted), and three state-of-the-art neural networks designed for medical image processing (Vnet, HighRes3dNet and ScaleNet). The experiments were conducted on brain datasets from a public database. Our results suggest that T1 images perform better than T2, but the results further improve when combining both sequences. The lowest mean average error over the entire head (MAE = 101.76 ± 10.4 HU) was achieved combining T1 and T2 scans with HighRes3dNet. All tested deep learning models achieved significantly lower MAE (p < 0.01) than a well-known atlas-based method., This work was supported by the Spanish Government grants TEC2016-79884-C2 and RTC-2016-5186-1, and by the European Union through the European Regional Development Fund (ERDF)

Thalamocortical connections are altered following very preterm birth but it is unknown whether structural and functional alterations are linked and how they contribute to neurodevelopmental deficits. We used a multimodal approach in 27 very preterm and 35 term-born children and adolescents aged 10–16 years: Structural thalamocortical connectivity was quantified with two measures derived from probabilistic tractography of diffusion tensor data, namely the volume of thalamic segments with cortical connections and mean fractional anisotropy (FA) within the respective segments. High-density sleep EEG was recorded and sleep spindles were identified at each electrode. Sleep spindle density and integrated spindle activity (ISA) were calculated to quantify functional thalamocortical connectivity. In term-born participants, the volume of the global thalamic segment with cortical connections was strongly related to sleep spindles across the entire head (mean r = .53 ± .10; range = 0.35 to 0.78). Regionally, the volume of the thalamic segment connecting to frontal brain regions correlated with sleep spindle density in two clusters of electrodes over fronto-temporal brain regions (.42 ± .06; 0.35 to 0.51 and 0.43 ± .08; 0.35 to 0.62) and the volume of the thalamic segment connecting to parietal brain regions correlated with sleep spindle density over parietal brain regions (mean r = .43 ± .07; 0.35 to 0.61). In very preterm participants, the volume of the thalamic segments was not associated with sleep spindles. In the very preterm group, mean FA within the global thalamic segment was negatively correlated with ISA over a cluster of frontal and temporo-occipital brain regions (mean r = −.53 ± .07; −.41 to −.72). No association between mean FA and ISA was found in the term-born group. With this multimodal study protocol, we identified a potential misalignment between structural and functional thalamocortical connectivity in children and adolescents born very preterm. Eventually, this may shed further light on the neuronal mechanisms underlying neurodevelopmental sequelae of preterm birth., NeuroImage, 215, ISSN:1053-8119, ISSN:1095-9572

Detailed computational anatomical models of the entire head are needed for accurate in silico modeling in a variety of transcranial stimulation applications. Models from different subjects help to understand and account for population variability. To this end, we have developed a new library of head models of 20 individuals, segmented from co-aligned multi-modal medical image data. The acquired image modalities allow to accurately model tissues with different material properties, such as electrical conductivity or spatially varying acoustic properties. The usefulness of the models is illustrated for two example applications.

KEY POINTS A healthy 50-year-old woman presented with acute onset of the worst headache of her life. She characterized the headache as constant, pulsating and over her entire head. It was associated with photophobia and fever without visual changes and neck stiffness. On examination, the patient was

Headaches often suddenly attack and this causes disruption to the various activities that are being carried out by ours. Headaches are pain in the head that can occur gradually or appear instantly almost unexpectedly. Headaches that appear can be felt light, heavy, and the area can be felt in the entire head or only in certain areas. There are many ways to deal with headaches, such as get some medication or get some massage therapy at certain points area, depending kind of headaches. However, the use of pain medication usually only has a short-term impact, so that at any time this headache reappears. Yoga therapy is an alternative in dealing with this headache. Yoga is indeed known as an alternative healing for certain diseases, one of them is headache. Although there is no exact and in-depth research on this issue, but some yoga movements are said to be able to deal with headaches, especially for those who often experience this headache attack at the wrong time, for example.

Background Manual paired‐point registration for navigated ENT‐surgery is prone to human errors; automatic surface registration is often caught in local minima. Methods Anatomical features of the human occiput are integrated into an algorithm for surface registration. A vector force field is defined between the patient and operating room datasets; registration is facilitated through gradient‐based vector field analysis optimization of an energy function. The method is validated exemplarily on patient surface data provided by a mechanically positioned A‐mode ultrasound sensor. Results Successful registrations were achieved within the entire parameter space, as well as from positions of local minima that were found by the Gaussian fields algorithm for surface registration. Sub‐millimetric registration error was measured in clinically relevant anatomical areas on the anterior skull and within the generally accepted margin of 1.5 mm for the entire head. Conclusion The satisfactory behavior of this approach potentially suggests a wider clinical integration.

As children develop, they differ from adults in a number of important ways, including anatomy, metabolism, immune system, and the extent of myelination of the nervous system. As a consequence, equivalent exposures to radiation from mobile phones result in different doses to specific tissues in children compared with adults. Higher doses are likely to have more severe implications in the young. A young child’s skull is not only smaller and thinner than an adult’s, but also has dielectric characteristics closer to those of soft tissues, probably due to a higher water content. The young skull better matches the electromagnetic characteristics of the skin and brain. As a result, finite-difference time-domain (FDTD) simulations confirm field penetration and higher specific absorption rate (SAR) in deeper structures in the young brain. If the peak spatial SAR (psSAR) is modeled in the entire head, as current testing standards recommend, the results for adults and children are equivalent. Our anatomically based evaluations rely on FDTD simulations of different tissues within the brain and confirm that the psSAR in a child’s brain is higher than in an adult’s brain.

While the acquisition and analysis of 3D faces has been an active area of research for decades, it is still a complex and demanding task to accurately model the entire head and ears. Having accurate models would for example enable virtual design of hearing devices. In this paper, we describe a complete framework for surface registration of complete human heads where the result is point correspondence with a very high number of points. The method is based on a volumetric and multi-scale non-rigid registration of signed distance fields. The method is evaluated on a set of 30 human heads and the results are convincing. The output can for example be used to compute statistical shape models. The accuracy of predicted anatomical landmarks is on the level of experienced human operators.

OBJECTIVE The purpose of this study was to investigate the feasibility of a surface-based registration method based on a low-cost, hand-held Sense three-dimensional (3D) scanner in image-guided neurosurgery system. METHODS The scanner was calibrated prior and fixed on a tripod before registration. During registration, a part of the head surface was scanned at first and the spatial position of the adapter was recorded. Then the scanner was taken off from the tripod and the entire head surface was scanned by moving the scanner around the patient's head. All the scan points were aligned to the recorded spatial position to form a unique point cloud of the head by the automatic mosaic function of the scanner. The coordinates of the scan points were transformed from the device space to the adapter space by a calibration matrix, and then to the patient space. A 2-step patient-to-image registration method was then performed to register the patient space to the image space. RESULTS The experimental results showed that the mean target registration error of 15 targets on the surface of the phantom was 1.61±0.09 mm. In a clinical experiment, the mean target registration error of 7 targets on the patient's head surface was 2.50±0.31 mm, which was sufficient to meet clinical requirements. CONCLUSIONS It is feasible to use the Sense 3D scanner for patient-to-image registration, and the low-cost Sense 3D scanner can take the place of the current used scanner in the image-guided neurosurgery system.

In many cases, when we present a video to users, we present sound too. Hence, the senses of sight and hearing are stimulated, improving the users' sensation of presence. In addition, recently, several virtual reality systems using wind have been built to enhance this sense of presence. If we use wind, users do not need to use additional devices for sensing presence because in such cases, we can present them with non-contact sensations. Therefore, wind-based systems do not hamper an improvement in the sense of presence. In fact, some studies have concluded that presenting wind and video simultaneously improves the sense of presence. However, in these studies, wind sources were arranged rather sparsely. In this sparse arrangement, we are not sure whether a precise environment can be reproduced. Therefore, we have examined the perception of wind direction by the entire head.

Mild traumatic brain injury (TBI) from focal head impact is the most common form of TBI in humans. Animal models, however, typically use direct impact to the exposed dura or skull, or blast to the entire head. We present a detailed characterization of a novel overpressure blast system to create focal closed-head mild TBI in mice. A high-pressure air pulse limited to a 7.5 mm diameter area on the left side of the head overlying the forebrain is delivered to anesthetized mice. The mouse eyes and ears are shielded, and its head and body are cushioned to minimize movement. This approach creates mild TBI by a pressure wave that acts on the brain, with minimal accompanying head acceleration-deceleration. A single 20-psi blast yields no functional deficits or brain injury, while a single 25-40 psi blast yields only slight motor deficits and brain damage. By contrast, a single 50-60 psi blast produces significant visual, motor, and neuropsychiatric impairments and axonal damage and microglial activation in major fiber tracts, but no contusive brain injury. This model thus reproduces the widespread axonal injury and functional impairments characteristic of closed-head mild TBI, without the complications of systemic or ocular blast effects or head acceleration that typically occur in other blast or impact models of closed-skull mild TBI. Accordingly, our model provides a simple way to examine the biomechanics, pathophysiology, and functional deficits that result from TBI and can serve as a reliable platform for testing therapies that reduce brain pathology and deficits.

The benefit of hyperthermia as a potent modifier of radiotherapy has been well established and more recently also the combination with chemotherapy was shown beneficial. Also for head and neck cancer, the impact of hyperthermia has been clinically demonstrated by a number of clinical trials. Unfortunately, the technology applied in these studies provided only limited thermal dose control, and the devices used only allowed treatment of target regions close to the skin. Over the last decade, we developed the technology for deep and controlled hyperthermia that allows treatment of the entire head and neck region. Our strategy involves focused microwave heating combined with 3D patient-specific electromagnetic and thermal simulations for conformal, reproducible and adaptive hyperthermia application. Validation of our strategy has been performed by 3D thermal dose assessment based on invasively placed temperature sensors combined with the 3D patient specific simulations. In this paper, we review the phase III clinical evidence for hyperthermia in head and neck tumors, as well as the heating and dosimetry technology applied in these studies. Next, we describe the development, clinical implementation and validation of 3D guided deep hyperthermia with the HYPERcollar, and its second generation, i.e. the HYPERcollar3D. Lastly, we discuss early clinical results and provide an outlook for this technology.

The most uncertain input parameters that often considered for calibration in water distribution system hydraulic model are pipe roughness coefficients and nodal demands. Both pipe roughness coefficients and nodal demands are considered to be calibrated in the calibration process, which works alternately. The calibration model was formulated as a constrained optimization problem. The entire head losses under different loading conditions are introduced in the objective function to guide the calibration direction, which can make consistent calibration effects on different loading conditions. The calibration model uses real-coded genetic algorithm along with a general network solver (EPANET 2.0) to adjust pipe roughness coefficients and nodal demands multipliers until the preset criteria are meet. The approach was applied in the calibration of a real-life water distribution system hydraulic model in China, which takes three loading conditions (max, min and average hour) into consider. The results show that the approach works well in achieving good calibration results, which match field observation in a reasonable level and meet engineering requirements.

PRESENTATION A 62-year-old woman’s dermatologic difficulties were compounded when light treatment for psoriasis spurred pemphigus foliaceus; an occurrence very rarely noted in the medical literature. She presented with an erythematous, crusted eruption involving her entire head and neck and most of her trunk. The lesions developed several months after consecutive exposures to narrowband ultraviolet B (UVB) phototherapy for chronic plaque psoriasis (Figure 1).

We report the newly developed Micro-CT, which allows us to observe the individual animal over a long experimental period and to compare changes in pulp tissue in relation to growth and aging without considering individual differences. Further, we used pathological examination to prove similar the result observing from Micro-CT. We have examined wound healing of teeth after pulpotomy in rats, and could clearly observe histopathological changes in the affected teeth and the absorption of temporary filling material and pulp capping agents. In cases with breakage of the dental crown, the CT images agreed with the pathological observations, and it was possible to estimate the time of breakage. In vivo Micro-CT is possible to apply in continuous recording of small experimental animals, such as rats, under anesthesia and the result is sufficiently high. High-quality image was obtained in of the entire head region of the rat. It was suggested that this method can be used for long-term continuous observation of changes in the teeth conditions after pulpotomy in experimental animals. We report the newly developed Micro-CT, which allows us to observe the individual animal over a long experimental period and to compare changes in pulp tissue in relation to growth and aging without considering individual differences.

For accurate simulation studies on distribution of electromagnetic field induced by Trancranial Magnetic Stimulation, a real human head conductivity model with deep cerebral structure was reconstructed from MRI raw data, by using of MIMICS and ANSYS. This model reflects geometric structural information of Scalp, Skull, Cerebrospinal Fluid (CSF), Gray Matter, White Matter, Cerebellum, Ventricle and Eye-balls. The ventricular structure has relatively higher conductivity, whose effect on induced field could not be neglected. This paper mainly introduces the method to establish the ventricle part of the entire head model, which is used for ANSYS low-frequency magnetic simulation, while the way to generate other parts is similar and accomplished. On the platform of-fered here, study on specific individual subject would be easy and practicable. Deep structures will be produced vectorial in the future work.

Most jaw muscles are complex, multipennate with multiple components. The morphologic heterogeneity of masticatory muscles reflects their functions. We hypothesized that the volume of masticatory muscles changes between jaw closing and opening, and that there is a difference in the volume change among the muscles. Magnetic resonance images of the entire head were obtained in ten normal young adult subjects before and after maximum jaw opening. The volume changes of the masseter, medial, and lateral pterygoid muscles were measured. Only slight changes were seen in the masseter and medial pterygoid muscles. The lateral pterygoid muscle, however, significantly decreased its volume during jaw opening. The results provide normative values of muscle volume in living subjects, and suggest that the volume changes differ among jaw muscles.

There are various recommendations about keeping operating gowns sterile, but the validity of these recommendations has not been definitively established. The purpose of this study was to use bacterial cultures to identify which areas of operating gowns are vulnerable to infection and which are safe against infection, as well as to find ways to improve bacterial identification and to prevent contamination. There were statistically significant differences according to year, as follows: F1, F4, B1, and B3. Based on 2009's results, when assisting with putting on OR gowns, we wore sterile gloves, sterile vests, and helmet-shaped hats which cover the entire head area to prevent rear area infections. Also, we performed bacterial identification immediately after finishing operations in 2010. The results showed that in this study, the areas of F1, F4, B1, B3, and B4 exhibited significant differences in bacterial identification.

The purpose of this study was threefold: to estimate the organ doses and effective doses (EDs) for seven neurovascular imaging protocols, to study the effect of beam collimation on ED, and to derive protocol-specific dose-area product (DAP)-to-ED conversion factors.A cone-beam CT system was used to measure the organ doses for seven neurovascular imaging protocols. Two datasets were obtained: seven protocols without beam collimation (FOV, entire head) and four with beam collimation (FOV, from the base to the top of the skull). Measurements were performed on an adult male anthropomorphic phantom with 20 metal oxide semiconductor field-effect transistor (MOSFET) detectors placed in selected organs. The DAP values were recorded from the console. The EDs of five protocols were also estimated using Monte Carlo simulations software. The ED values were computed by multiplying measured organ doses to corresponding International Commission on Radiological Protection tissue-weighting factors.Without collimation, the EDs ranged from 0.16 to 1.6 mSv, and the DAP-to-ED conversion factors ranged from 0.035 to 0.076 mSv/Gy·cm(2). For the four protocols investigated with beam collimation, the ED was reduced by a factor of approximately 2, and the DAP-to-ED conversion factors were reduced by approximately 30%. For the five protocols also estimated with the Monte Carlo method, the estimated EDs were in agreement (20% deviation) with those determined by the MOSFET method.We have estimated ED for standard adult neuroimaging protocols in a 3D rotational angiography system. Our results provide a simple means of ED estimation using DAP console readings.

Clinical studies have established a strong benefit from adjuvant mild hyperthermia to radio- and chemotherapy for many tumor sites, including the head and neck. The recently developed HYPERcollar allows applying local radiofrequency hyperthermia to tumors in the entire head and neck. Treatment quality is optimized using a combination of electromagnetic and temperature simulators and assessed using invasively placed thermometers. To replace the current invasive thermometry, we are investigating if magnetic resonance (MR) measurements can be exploited for continuous and 3D thermal dose assessment during treatment. In this study, we designed an MR compatible laboratory prototype applicator. We showed that the laboratory prototype applicator, based on re-designed patch antennas, enables MR guided focused heating and allows effective mitigating of image distortion. Hence, we conclude that hybrid MR-hyperthermia treatment in the head and neck region is feasible. The novel hybrid laboratory prototype further allows thorough investigation of patient and systems induced imaging distortions in preparation of the design of a clinical applicator.

A pituitary adenoma was diagnosed via histopathologic examination in an aged female Dumeril's ground boa, Acrantophis dumerili. The snake exhibited postural abnormalities, dull mentation, and poor muscle tone prior to death. Pituitary neoplasms appear to occur very rarely in reptiles, but may be underreported if the pituitary gland is not routinely examined. This report illustrates the importance of submitting the brain or entire head for microscopic evaluation.

Iatrogenic comminution of the phalangeal head during management of phalangeal neck fractures has not been previously investigated.To investigate the causes and outcomes of this particular iatrogenic complication.A database of phalangeal neck fractures over a six-year period (2006 to 2011) was reviewed for this iatrogenic complication. Special attention was devoted to documenting the cause and pattern of comminution of the phalangeal head, as well as the outcome in range of motion.Of 152 cases treated during the study period, there were five (two children and three adults) with comminution. Two patterns of comminution were encountered: splitting and fragmentation of the phalangeal head. The complication occurred during open reduction and K-wire fixation, or during closed reduction in the emergency room. The outcome was generally poor and worse in patients with fragmentation of the entire head. Two of the five cases ultimately resulted in medicolegal claims.Comminution of the phalangeal head is a serious iatrogenic complication that may occur during the management of phalangeal neck fractures. Awareness of this complication is important and attempts should be made to avoid it.La comminution iatrogène de la tête de la phalange pendant la prise en charge de fractures de la phalange distale n’a jamais été examinée auparavant.Explorer les causes et les issues de cette complication iatrogène.Les chercheurs ont analysé une base de données sur les fractures de la phalange distale sur une période de six ans (2006 à 2011) pour dépister cette complication iatrogène. Ils se sont attardés à étayer la cause et le profil de la comminution de la tête de la phalange, ainsi que l’issue de l’amplitude de mouvement.Sur les 152 cas traités pendant la période de l’étude, cinq (deux enfants et trois adultes) ont présenté une comminution. Il y avait deux profils de comminution : une fente et une fragmentation de la tête de la phalange. La complication s’est produite pendant la réduction ouverte et la fixation par broche de Kirschner, ou pendant la réduction fermée à l’urgence. L’issue était généralement médiocre, et pire encore chez les patients présentant une fragmentation de toute la tête de la phalange. Deux des cinq cas ont donné lieu à des réclamations médicolégales.La comminution de la tête de la phalange est une complication iatrogène qui peut se produire pendant la prise en charge des fractures de la phalange distale. Il est important de connaître cette complication et de tenter de l’éviter.

✓ Although hair removal prior to neurosurgery may increase the risk of infection, the practice of shaving the patient's entire head is still common, particularly in implant surgery. The authors describe a technique for implanting a deep brain stimulation electrode without shaving the patient's hair and present a retrospective analysis of 261 implantations in 221 cases.

A new high-resolution MR protocol for the combined assessment of neurovascular arterial anatomy and subsequent evaluation of inflammatory disease in cranial vessels walls has been investigated. First-pass contrast-enhanced MR angiography (CE-MRA) in combination with parallel imaging at high field permits the depiction of the neurovascular geometry with large coverage, including the aortic arch, supraaortic vessels, and almost the entire head, with high, submillimeter detail. Utilizing the remaining contrast agent, postcontrast T1-weighted turbo spin-echo (TSE) imaging was used to generate late enhancement images of the vessel walls to assess the morphology and potential inflammatory changes in cranial arteries with high in-plane (195 × 260 μm2) spatial resolution. As a result, a combined analysis of neurovascular arterial anatomy as well as cranial vessel wall inflammations could be achieved in less than 45 minutes in all studies. The feasibility and clinical value for the diagnosis of rheumatologic diseases and simultaneous arteriosclerotic involvement was demonstrated in seven patients with suspected giant cell arteritis (GCA). Excellent CE-MRA image quality could be achieved and even vascular geometry of small superficial cranial arteries could be successfully visualized using single dose (0.1 mmol/kg) contrast agent administration and a dedicated phased-array head and neck coil at 3T. J. Magn. Reson. Imaging 2006. © 2006 Wiley-Liss, Inc.

Although hair removal prior to neurosurgery may increase the risk of infection, the practice of shaving the patient's entire head is still common, particularly in implant surgery. The authors describe a technique for implanting a deep brain stimulation electrode without shaving the patient's hair and present a retrospective analysis of 261 implantations in 221 cases.

This paper presents Langwidere, a facial animation system that integrates hierarchical spline modeling with simulated muscles based upon local area surface deformations. The multi-level shape representation of a hierarchical spline provides control over the extent of deformations, while at the same time reducing the amount of data needed to define the surface. The facial model is constructed from a single closed surface defining the entire head and internal structures of the mouth cavity. Simulated muscles are attached to various levels of the surface with more rudimentary levels substituting for bone such as the skull and jaw. The combination of a hierarchical model and simulated muscles provides a smooth surface with precise and flexible control over surface shape. >

We wish to thank Dr. Wierzbicka for the interesting comments to the paper ‘‘Open partial horizontal laryngectomies: a proposal for classification by the working committee on nomenclature of the European Laryngological Society’’ by Succo et al. [1]. Its declared aim, as well as that of the other ELS classifications on oncologic subjects published in the past years [2–4] is to create a common platform for sharing surgical data among the greatest number of institutions worldwide. In this sense, the specific intent of our working committee was to keep the classification as easy as possible, including only well-known, standardized, and widely accepted procedures, reproducible among the entire head and neck surgical community. Clearly, this is required to make choices among the dozens of types of open partial laryngectomies described in the literature, focusing on those that, in our opinion, still play a pivotal role between the two extremes of transoral microsurgery on one hand, and total laryngectomy on the other. Among the many less common types of open partial laryngectomies, horizontal glottectomy, described in 1978 by Calearo and Teatini [5] (who were both, by the way, strictly linked to our laryngological school), definitely represents a procedure that is nowadays quite limited in its application since it has been overshadowed, for the reported indications, by transoral laser microsurgery and radiotherapy. Nevertheless, we are perfectly aware of the fact that any classification of surgical procedures should be regarded as a temporary tool that is being continuously reshaped and modified whenever consistent limits in its application should become evident in the future among the head and neck cancer community.

This interactive feature presents the case of a 54-year-old woman with a history of mild, intermittent headaches who awoke from sleep with a squeezing, stabbing pain around her entire head. Test your diagnostic and therapeutic skills at NEJM.org.

The survival of patients with glioblastoma multiforme is extremely poor, the 5-year survival rate being almost zero. The cause of failure is almost exclusively local progression of tumor, the remainder is due to complications of treatment. Although this tumor is clearly radiation resistant, there is evidence of a dose response relationship. Using a thin slice CT scan of the entire head of a patient with glioblastoma multiforme, 3-dimensional radiation treatment plans were developed for treatment to a dose of 90 cobalt-Gray-equivalent (CGE). Dose distributions using protons were compared to those using x-rays. The results showed advantages for the proton beam technique. Namely the proton plan irradiated less non-target brain than the x-ray plan; this was especially so in the decrease of coverage of deep-seated structures. The volume of non-target brain that received more than 70 CGE was 175 ml for the x-ray plan and 94 ml for the proton plan. This study indicates that for a subpopulation of patients with glioblastoma multiforme, at least 90 CGE could be delivered with proton beam techniques to the target with only small volumes of normal brain structures receiving more than 70 CGE.

Purpose To determine whether the size and configuration of the optic chiasm in humans with albinism is different from that in normal control subjects. Methods Seventeen patients and 15 control subjects underwent magnetic resonance imaging of the entire head. Images were reformatted to the chiasm region and analyzed with observer-independent morphometry and measurements by a blinded observer. Results The albino group showed significantly smaller chiasmatic widths, smaller optic nerves and tracts, and wider angles between nerves and tracts. Statistical morphometry showed a different configuration of the optic chiasm. Conclusions Size and configuration of the optic chiasm in humans with albinism are distinctly different from those in normal control subjects and reflect the atypical crossing of optic fibers.

Presentation of a synthesized 3‐D audio environment depends heavily on the use of head‐related transfer functions (HRTF’s) when headphones or small numbers of loudspeakers are used for the actual sound sources. The detailed differences between individual’s HRTF’s are a serious hindrance to the widespread use of such virtual acoustic environments, as standard HRTF models do not perform adequately for large populations. Currentmethods of obtaining HRTF’s are very time consuming and inconvenient for the subject, consisting of long periods of immobility during measure‐ments. Two new methods under consideration for obtaining an individualized HRTF are discussed which use physical models of the pinnae structure and geometric measurements of the entire head and pinnae. Comparisons of the results as compared with established measurement techniques were made. Subjective comparisons using headphone presentations of virtual complex sound sources were also made.

• A totally implantable infusion pump (Infusaid) has been developed to achieve continuous drug delivery for long periods of time. The recent availability of a dualcatheter totally implantable infusion pump permits the infusion of both external carotid arteries simultaneously. This has obvious advantages for the treatment of extensive tumors of the head and neck that extend across the midline. Likewise, for the first time, unilateral local-regional disease that extends inferiorly beyond the nutrient field of the external carotid artery may be treated with intra-arterial infusion chemotherapy without the need to infuse the common carotid or innominate arteries. Unilateral infusion of the entire head and neck is accomplished by using the dual-catheter pump to infuse both the thyrocervical trunk and the external carotid artery. ( Arch Otolaryngol 1982;108:703-708)

Mere submergence of a duck's head in water produces instantaneously, at whatever stage of respiration the act be performed, cessation of breathing, Such cessation is due to reflex action because— (1) It persists under light anaesthesia, where voluntary control is lost, and disappears like other reflexes in deep anaesthesia. (2) It occurs constantly and markedly in ducks which have been deprived of the cerebral hemispheres. Experiments on the normal duck showed that submersion of the end of the beak does not cause stoppage of breathing; that submersion of the nostrils causes but incomplete cessation; and that submersion of the entire head is required for its full production. Hence the receptors of the reflex are must be the sensory nerves which supply the mucous membrane and skin of these parts. The region of the glottis receives its sensory supply from branches of the glosso-pharyngeal nerve, the mucous membrane of the nostrils from the trigeminal, and this also supplies the skin. It must be through these nerves that the impulse is carried to the respiratory centre to inhibit its rhythmical activity. So, when a duck's head is submerged, reflex action causes cessation of breathing; but, as will be shown in the next paper, when a duck submerges its own head, whether merely to secure something under the surface of the water or in the diving position, other reflexes appear which add to this and make the condition much more pronounced.

at Antioch, French soldiers unearthed in 1934 a curious looking marble head which formed part of an ancient cache of sculpture (pl. 3, figs. I-2).' Identified simply as a female head by the excavators of the Franco-American expedition to the Roman Syrian City, it is now in the Museum of Historic Art at Princeton. Seen from the front, the head assumes the shape of an egg. At the narrow end, which is the chin, a flake of the weathered marble surface has disappeared, and the entire head is rather battered. Yet the use of the Greek

F. N., a white man aged 66, was admitted to the Graduate Hospital of the University of Pennsylvania on July 11, 1950, because of swelling of the entire head, face, and neck. The patient stated that two months prior to admission he first noted that his lower eyelids were swollen in the morning. The swelling became progressively worse, so that his eyes were swollen shut in the morning, his neck veins became prominent, like cords, and his arms were swollen. He also began to notice distended veins on his chest and a sensation of being choked when he "stooped" over. All these symptoms were less severe after he was up and about. Physical examination revealed distended neck veins and numerous varices on the anterior chest wall, but no dependent edema. The rest of the examination revealed nothing significant. Laboratory studies showed a venous pressure of 310 mm. of water, a

In the recent epidemics of tinea capitis there is occasionally a need for roentgen epilation of children under the age of 3 years. While in many children this procedure can be carried out easily in the ordinary manner, there are some children who can be treated only after being anesthetized in order to insure immobilization. Such a procedure is especially indicated in a family in which several children are infected. If one child is left untreated, he then serves as a reservoir, making the possibility of reinfection of the older children after their initial succesful epilation very likely. MacKee and Cipollaro state that as a rule it is impossible, or at least very difficult, to depilate the entire head of a child under 2 or 3 years of age for the simple reason that the patient will not remain quiet. * In the past three years at the Children's Hospital 10

I. ASEPTIC PROTECTIVE SHEET FOR MASTOID SURGERY. One of the important problems confronting the aural surgeon is the maintenance of strict asepsis of the mastoid wound without unduly disfiguring the patient, even temporarily, by extensive removal of hair. The practice of different operators, as regards the preparation of the field for a mastoid operation, varies from removal of only a small amount of hair immediately surrounding the area to be opened, to a close shaving of the entire head. I have never felt justified in exposing an extensive area of the scalp, except in a premeditated brain investigation, and yet, in my efforts to save the patient from unnecessary loss of hair, I have frequently been sorely troubled by hairs encroaching on the wound at a critical stage of the operation. In preparing for a simple mastoidectomy it has been my custom to have the scalp shaved for a distance

To the Editor.— Kava-kava, or Piper methysticum , is a plant indigenous to many South Pacific islands. While studies have confirmed the purported mild sedative effect of the ingested extract, several therapeutic protocols had to be revised due to toxic and allergic dermatologic reactions. 1 We describe herein a case of a patient with an unusual reaction to kava-kava. Report of a Case.— This 44-year-old man presented with a confluent nonpruritic extreme erythema and slight edema involving his entire head and neck, and the upper portions of his back and chest. He reported drinking greater than four cups of kava-kava tea on the previous night, and awoke with the erythema. He was seen at the clinic 12 hours after ingestion and treated with a four-day course of oral prednisone. Involution of the erythema and edema, with some scaling, began one week following the visit. He drank kava-kava tea once before, three

Stiffness of the neck is often found in clinical practice accompanying meningeal irritation. Yet, paradoxically enough, patients have been erroneously diagnosed as having had meningitis because of its presence. We had to note the conditions where stiff neck was found, for it soon became obvious that not all stiff necks were due to meningeal irritation. In order to establish a diagnosis when this condition is present, one has to collect the evidence based on inspection, percussion, palpation and rarely auscultation. The factors causing stiffness of the neck originate in nerves, muscles, bones, fascia, ligaments, glands and other structures. The neck is inspected from front, side and back. One notes how the head is held. Is it braced and splinted to avoid pain? Is there pain in certain positions only? Is pain absent? Is the entire head and neck moved in a marionette manner or is the neck stiffened so that

In the practice of surgery, the successful bandaging and dressing of head wounds has always seemed to me a difficult feat. Patients with large wounds, requiring large dressings, usually need hospitalization, and every one knows the difficulty of keeping a head dressing on a restless or uncontrollable patient. Small operative and accidental wounds about the head are covered generally with a collodion dressing (which is difficult and painful of removal), or the entire head is swathed in bandages, much to the discomfort and dismay of the patient desirous of going about his usual duties. In the handling of quite a number of patients suffering with head wounds, the dressing presented in the accompanying illustration has been evolved, and, with it, the mode of closure, thus making the closure and dressing all part of the same technic. Since it was first used it has been tried many times and has proved

With our limited access to the literature we have been unable to find any satisfactory description for an arthroplasty of the shoulder-joint. Having a case for operation, we began the work on the cadaver and developed the following technic, which we believe is nearest anatomically correct of anything we have been able to find. In this operation we have utilized a portion of the short head of the biceps for a flap to interpose, because it is covered bymore dense tendinous sheath than any other structure in the neighborhood of the shoulder-joint, is correctly located anatomically and we believe in the majority of cases will furnish sufficient fascia and muscle to make a flap of necessary dimensions. The flap obtained is quite sufficient to line the glenoid fossa and cover the entire head of the humerus. In our clinical case there was considerable enlargement of the head of the humerus

This case is reported because of the unusual rapidity with which the symptoms developed and their extraordinary severity, leading to a fatal termination. REPORT OF CASE Onset. —E. S., a white woman, aged 63, first complained of symptoms on March 12, 1927, consisting chiefly of nausea and terrific pain over the entire head. The patient was perfectly well in every way on March 11. At 5 a. m. on the 12th, she awakened with a terrific pain in the temporal part of the head, extending over the eyes. It was extremely severe and different from any other previous headaches, associated with nausea and followed within two hours by vomiting. She found it impossible to retain any food that day. The extreme retching increased the pain in the head markedly. There was noticeable drowsiness the entire day. Codeine sulphate, one-half grain (32 mg.), slightly relieved the headache and somewhat controlled the

Weanling rats whose bodies were lead-shielded, were X-irradiated to defined areas of the head. Body growth, incisal tooth development, and histopathology of the tongue and glossopharyngeal area (throat) were studied for a period of 7 weeks following irradiation. An X-ray dose of 2000 rads to the head and throat caused injury to the tongue and palate which resulted in a reduction in food intake and a marked loss in weight of the exposed rats. The more extensive the head area irradiated the higher the mortality, attaining 100 per cent deaths at 9-10 days when the entire head was irradiated. Irradiation of the throat only with 2000 rads elicited 50 per cent deaths. There was a persistent reduction in the growth rate of the survivors compared to that of non-irradiated controls. These effects were not seen if the base of the tongue only was irradiated. The maxillary incisors, which received 120 rads through the lead shielding, after 5-7 weeks were either lost or grew abnormally in all throat-irradiated rats. The same dose of X-radiation to the incisors of rats in which the base of the tongue only was irradiated, had no deleterious effect on their development. The possibility of a relationship between metabolic disturbances caused by throat irradiation, and growth of the incisors receiving low doses of X-radiation, is postulated and discussed. (Author)