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At least 145 records · Page 8Linked to original sources
PubMed2006

[Application of skin soft tissue expansion to reconstruction of scalp soft tissue defect].

OBJECTIVE: To explore an improved method of reconstructing the scalp soft tissue defect with the expanded skin soft tissue and treating and preventing the related complication. METHODS: From October 2002 to June 2005, 32 patients (20 males and 12 females, aged 5-48 years) underwent reconstruction of the scalp soft tissue defects with the expanded scalp soft tissue in the two-stage operation. In the first stage, a tissue expander (cylindrical form, 50-250 ml) was implanted into the skin to achieve a skin soft tissue expansion. After a sufficient skin expansion (8 cm X 5 cm to 25 cm X 23 cm) was made by the routine water effusion for 6-16 weeks, a properly-designed skin flap was taken and transferred to reconstruct the scalp soft tissue defect in the second-stage of the operation. All the scalp defects were left after the resections of the scalp lesions, which ranged in size from 7 cm x 5 cm to 20 cm x 20 cm. RESULTS: After operation, all the 32 patients had their scalp defects repaired and reconstructed well. The expanded skin flaps of all the 32 patients survived except 1 patient who had a necrosis of the distal epidermis of the flap, which healed after the dressings of the wound. The hair grew well and the scars were hidden with a satisfactory appearance. Four patients developed complications (necrosis of the distal flap in 1 patient, hematoma in 1, expander exposure in 1, and wound rupture in 1). CONCLUSION: Reconstruction of the scalp soft tissue defect with the skin soft tissue expansion is an ideal method.

Adolescent↗
PubMed1997

Experience with a make-it-yourself scalp extender with hooks.

BACKGROUND: Silicone scalp extenders have been shown to facilitate the process of scalp reduction surgery. OBJECTIVE: This report demonstrates how scalp extender devices can easily be made in the physician's office out of materials that are commercially available. METHODS: A scalp extender is made by bonding a narrow strip of Dacron-reinforced Duralastic silicone sheeting to each end of a long strip of plain Duralastic silicone sheeting. A stainless steel plate of hooks is then secured to each end of the extender. At the time of the first standard scalp reduction surgery, one extender device about 3.0 x 5.0 cm is placed in the subgaleal plane, in the transauricular direction, with hooks piercing the galea 1 cm caudad to the dense-in-quantity hair fringe margin. The circumferencial approach will accommodate the placement of a second extender device in the anterior-posterior direction to elevate the posterior hair fringe. To prevent adhesion of the galea to the periosteum around the devices, a sheet of plain silicone 15 x 20 cm is placed over the periosteum before the extenders are inserted. The extenders are replaced with shorter devices 3-4 weeks later. RESULTS: Usually the average width of bald scalp can be closed fringe to fringe in three operations as compared with five or six operations when using standard scalp reduction procedures. CONCLUSIONS: The scalp extender device described can be custom made in many different sizes. Its use has significantly changed the author's surgical treatment of pattern alopecia.

Alopecia↗
PubMed1985

Nervous propagation along 'central' motor pathways in intact man: characteristics of motor responses to 'bifocal' and 'unifocal' spine and scalp non-invasive stimulation.

In 23 healthy adult volunteers motor action potentials (MAPs) were elicited in upper and lower limb muscles during stimulation of appropriate sites at spinal and scalp level, through skin electrodes. 'Bifocal' stimulation of scalp and spine motor tracts was performed with 2 plaques (3.5 cm2 each), delivering single pulses of 440-940 mA, less than 50 microseconds in duration, which elicited high voltage (up to 10 mV) MAPs in arm and leg muscles. 'Unifocal' stimulation of scalp was carried out through a cathode consisting in a belt or in a series of rectangular interconnected plaques secured around the head, 1-2 cm rostral to the nasion-inion plane, and in a circular anode placed on the appropriate scalp site. MAPs with similar amplitude-latency characteristics were recorded with both 'bifocal' and 'unifocal' stimulating methods. However, the 'unifocal' stimulation necessitated 5-10 times less current than the 'bifocal' one. The 'unifocal' device using the interconnected plaques (6-12 in number) provided the most tolerable stimuli with the lowest amount of current (60-106 mA, rectangular pulses of 100-150 microseconds). Conduction times and velocities of motor pathways in various 'central' and 'peripheral' districts were calculated. Voluntary contraction of target muscles remarkably enhanced MAP amplitudes during scalp, but not during spine stimulation. A nerve action potential was recorded from ulnar nerve during scalp stimulation. MAPs in hand muscles to scalp stimulation were obliterated by the simultaneous activation of the peripheral fibres innervating the target muscle, because of collision between ortho- and antidromically propagated motor impulses. Anodal stimuli showed liminal values significantly lower than the cathodal ones. Mapping studies have been carried out with 'unifocal' scalp stimulation by using different types of anode and of stimulus parameters.

Action Potentials↗
PubMed2001

Identification of the temporal components of seizure onset in the scalp EEG.

BACKGROUND: The identification of the earliest indication of rhythmical oscillations and paroxysmal events associated with an epileptic seizure is paramount in identifying the location of the seizure onset in the scalp EEG. In this work, data-dependent filters are designed that can help reveal obscure activity at the onset of seizures in problematic EEGs. METHODS: Data-dependent filters were designed using temporal patterns common to selected segments from pre-ictal and ictal portions of the scalp EEG. Temporal patterns that accounted for more variance in the ictal segment than in the pre-ictal segment of the scalp EEG were used to form the filters. RESULTS: Application of the filters to the scalp EEG revealed temporal components in the seizure onset in the scalp recording that were not obvious in the unfiltered EEG. Examination of the filtered EEG enabled the onset of the seizure to be recognized earlier in the recording. The utility of the filters was confirmed qualitatively by comparing the scalp recording to the intracranial recording and quantitatively by calculating correlation coefficients between the scalp and intracranial recordings before and after filtering. CONCLUSION: The data-dependent approach to EEG filter design allows automatic detection of the basic frequencies present in the seizure onset. This approach is more effective than narrow band-pass filtering for eliminating artifactual and other interference that can obscure the onset of a seizure. Therefore, temporal-pattern filtering facilitates the identification of seizure onsets in challenging scalp EEGs.

Algorithms↗
PubMed2001

Temporal epileptogenesis: localizing value of scalp and subdural interictal and ictal EEG data.

PURPOSE: To determine the value of scalp epileptiform EEG data and subdural interictal spikes in localizing temporal epileptogenesis among patients requiring invasive recordings. For this delineation, we related such factors to site of subdural seizure origin in 27 consecutive patients. METHODS: Patients with temporal lobe epilepsy whose non-invasive lateralizing data were inconclusive and therefore required subdural electroencephalography were studied. All patients had (a) 24-h scalp telemetered EEGs, (b) adequate bitemporal subdural placements with an inferomesial line extending from a posterior burr hole anteriorly to <2.5 cm from anterior uncus and a lateral line reaching within 2.5 cm of the temporal tip, and (c) > or =2 subdurally recorded seizures. RESULTS: Three hundred one (96%) of 314 subdurally recorded clinical seizures involving all 27 patients arose from a discrete focus; 266 (85%) arose from mesial temporal regions, which was the origin of the majority of seizures in 24 (89%) patients. The majority of subdural seizures arose ipsilateral to the majority of scalp EEG spikes in 22 (81%) of 27, and most subdural seizures of 15 (75%) of 20 arose ipsilateral to scalp seizures. Lateralization of interictal subdural spikes correlated with that of subdural seizures in 74-92% of patients, depending on the method of spike compilation: for example, most subdural seizures arose from the same lobe of most consistent principal temporal spikes in 92% of patients. These indices of epileptogenesis also appeared more commonly on the side of effective (> or =90% improvement) temporal lobectomy than contralaterally in the following proportions: most consistent principal subdural spikes, 86% of patients ipsilateral vs. 9% contralateral; scalp-recorded clinical seizures, 55% vs. 18%; scalp EEG spikes, 45% vs. 9%. CONCLUSIONS: Even among patients whose scalp data are sufficiently complex to require invasive recording for clarification, lateralization of temporal scalp interictal and ictal epileptiform activity and subdural interictal spikes should be included when assessing the side of temporal epileptogenesis.

Brain Mapping↗
PubMed1998

Anchoring galeal flaps for scalp reduction procedures.

This article describes an operative technique, based on the use of three anchoring galeal flaps, aimed at reducing the percentage of "stretch-back" that occurs after performing scalp reduction procedures. In 12 male patients undergoing a midline scalp reduction procedure, three rectangular (2 x 3 cm) galeal flaps in direct continuity with the longitudinal margin of the left scalp flap were sutured individually to the galeal undersurface of the right scalp flap to draw the two scalp flaps toward the midline of the scalp and to relieve the wound margins of closing tension. Tattoo marks were placed on the patient's scalp at the level of the vertical lines drawn through the external auditory meatuses (A1-A2) and 6 cm more posterior (B1-B2) to measure the movement and stretching of the scalp. The results were compared with those obtained from a control group of 13 male patients who underwent the same surgical procedure but without the use of the anchoring galeal flaps. Mean stretch-back (as measured 4 weeks postoperatively) at level A1-A2 was 8.3 mm in the control group and 1.6 mm in the experimental group. The mean stretch-back at level B1-B2 was 7.7 mm in the control group and 0.9 mm in the experimental group. A statistically significant difference (p < 0.005) was found between data from the control and experimental groups regarding the above-reported stretch-back values at both levels. The use of the described galeal flaps allowed us to obtain an 80.93-percent and an 88.09-percent stretch-back reduction at levels A1-A2 and B1-B2, respectively, 1 month postoperatively.

Adult↗
PubMed2006

Giant eccrine adenocarcinoma of the scalp with intracranial invasion: resection and reconstruction using a vacuum-assisted closure device: technical case report.

OBJECTIVE AND IMPORTANCE: Carcinoma of the adnexal structures of the skin is a rare malignancy, and is even more unusual in the scalp. We report an unusual case of scalp adnexal carcinoma of eccrine origin that went untreated for years, resulting in a giant tumor with extension through the cranium. The tumor resection and reconstruction of the cranium and scalp defects posed unique challenges. CLINICAL PRESENTATION: A 54-year-old woman experienced a large recurrence of her scalp adnexal carcinoma after an incomplete wide local excision, which invaded through the cranium. INTERVENTION: The entire vertex of the scalp and cranium were removed en bloc. After cranioplasty, a free vascularized muscle flap was used for soft tissue coverage, but failed owing to poor vascular inflow. A large area of dura was left open, using a vacuum-assisted wound closure device to generate granulation tissue by secondary intention. Another split thickness skin graft was used to provide a cosmetically acceptable outcome. CONCLUSION: Scalp adnexal tumors of eccrine origin rarely metastasize and can be resected for cure with complete removal. Reconstruction options for large scalp and cranial tumors may be limited, and allowing the dura to granulate by secondary intention has been very rarely described. The novel use of a vacuum-assisted wound closure device was a very useful adjunct in this situation, and may be beneficial in the reconstruction of other patients with large scalp and cranial defects after neurosurgical procedures. It should be used with caution, since it may risk injury to a major venous sinus, especially when used in the midline, or cerebrospinal fluid leakage.

Adenocarcinoma↗
PubMed1988

Chronic extensive necrotizing abscess of the scalp.

Chronic subgaleal abscesses have been extremely rare since the advent of antimicrobial therapy. The majority of reported cases have occurred as acute infections following traumatic scalp lacerations or needle electrode insertion for fetal monitoring. The rich blood supply of the head makes widespread infection from a scalp surgical wound a very unlikely occurrence. Most acute infections of the scalp result in complete resolution with adequate early treatment. However, extensive purulent fibrosis of the scalp remains a potentially serious surgical complication. We report 2 cases of chronic necrotizing abscess of the scalp associated with a postsurgical scalp ulcer. The inflammatory process caused extensive necrotizing fibrosis (up to 2.5 cm thick) of the entire undersurface of the scalp and involved both the galea aponeurotica and the periosteum. We discuss the unique pathological features of this entity along with recommendations for its operative management and suggestions for flap design.

Abscess↗
PubMed1998

Scalp psoriasis, clinical presentations and therapeutic management.

BACKGROUND: The scalp is a well-known predilection site for psoriasis. Many patients indicate that scalp psoriasis is both psychologically and socially distressing. OBJECTIVE: The aim of the present investigation is to provide epidemiological data on the various manifestations of scalp psoriasis, as well as on its therapeutic management. METHODS: A questionnaire, targeted on scalp psoriasis, was mailed to patient subscribers of a Dutch journal on psoriasis. In total 1,023 forms were returned and evaluated. RESULTS: Remarkably, a relatively high occurrence of facial psoriasis (25%) and nail psoriasis (40%) was recorded. The dynamics of scalp psoriasis were rather similar to psoriasis at other sites with respect to the total duration of the disease and exacerbations/remissions. In 57% of the patients, psoriasis was psychologically and socially distressing, at least occasionally. Itch and scaling proved to be the leading symptoms, in terms of frequency of occurrence as well as in terms of distress. Therefore, these parameters should be regarded as primary efficacy criteria in the treatment of scalp psoriasis. On average, most patients were seen by the dermatologist 5 times a year. The majority of prescriptions (76%) was given by the dermatologist. The application of topical corticosteroids was by far the most frequent treatment modality. To our surprise, calcipotriol was used by 28% of patients. At the time of investigation calcipotriol was only available as ointment. Tar shampoos were used by 51% of the patients, although the clinical efficacy of such a shampoo has never been demonstrated in a controlled study. A remarkable observation was the lack of instruction on the duration of treatment and the frequency of applications. In fact, 72% of the patients used topical treatments, including topical corticosteroids, for more than 8 weeks, and 42% of the patients used an intermittent schedule of a few applications per week. CONCLUSIONS: Based on the present survey, the following profile for an optimal treatment of scalp psoriasis can be constructed: (1) effective applications a few times per week; (2) either a lotion or an emulsion, and (3) safety for long-term use.

Administration, Topical↗
PubMed2001

Telogen effluvium after allergic contact dermatitis of the scalp.

OBJECTIVE: After observing 2 cases of acute telogen effluvium induced by allergic contact dermatitis to hair dyes, we decided to evaluate the effects of acute contact dermatitis of the scalp on the hair cycle. DESIGN: Single-center, 6-month study of consecutive patients affected by acute scalp dermatitis. SETTING: Department of Dermatology, University of Bologna, Bologna, Italy. PATIENTS: Diagnosis of allergic contact dermatitis of the scalp was confirmed by patch testing. Eight women presenting with acute contact dermatitis of the scalp entered the study. Hair shedding was evaluated monthly for 6 months by pull test and wash test. Increased hair loss was detected in 4 of the 7 patients who completed the study. Hair loss was mild to moderate and appeared 2 to 4 months after the episode of scalp dermatitis. A scalp biopsy specimen from 2 patients confirmed the diagnosis of telogen effluvium. CONCLUSIONS: Allergic contact dermatitis of the scalp should be included among the possible causes of telogen effluvium. The pathogenesis of telogen effluvium caused by contact dermatitis is unknown but may be related to cytokine release during the inflammatory process.

Acute Disease↗
PubMed1995

Scalp lesions. A review of histopathologic and fine-needle aspiration biopsy findings.

We reviewed surgical and cytological scalp specimens at Loyola University Medical Center over an 8-year period. The incidence and types of pathologic entities that appeared in the scalp were tabulated, and the roles of surgery and fine-needle aspiration biopsy (FNAB) were investigated. There were 352 patients with scalp tissue biopsies. There were 41 primary malignancies, and 3 metastatic carcinomas. FNAB specimens were obtained from 36 other patients. Of these, 29 specimens showed malignant cytology. All of these patients had a previous diagnosis of malignancy. Scalp tissue biopsy specimens were far more likely to have a benign diagnosis than were FNAB specimens (P < 0.00001). This difference is probably due to the patients' histories and referring physicians. Healthy patients with a scalp lesion will generally present to a dermatologist, who will obtain a tissue specimen. In contrast, a patient with a history of malignancy with a scalp lesion will follow up with an oncologist, who may prefer FNAB to surgical procedures in order to diagnose such a lesion rapidly. The scalp is a common repository for metastatic tumors, most likely due to its rich vascularity. Awareness of this fact can be useful to dermatologists or oncologists in selecting the better diagnostic procedure for a patient.

Adolescent↗
PubMed1987

Angiosarcoma of the scalp: report of two cases with fatal pulmonary complications and a review of Japanese autopsy registry data.

Two cases of angiosarcoma of the scalp were reported. The patients were elderly men and died from pulmonary complications, including pneumothorax, pulmonary haemorrhage and pneumonia, associated with metastatic tumours in the lungs. The data recorded from 95 autopsies of patients with angiosarcoma in Japan during 1980-1984 were analyzed. According to the anatomical distribution of the primary tumour, the patients could be subdivided into a scalp group and non-scalp group. In both groups, the most common metastatic site was the lung. The patients of the scalp group had more frequent pulmonary complications such as pneumonia, haemothorax, atelectasis and pneumothorax, when compared with the patients of the non-scalp group. In particular, pneumothorax was observed only in the patients of angiosarcoma of the scalp. The results indicate that angiosarcoma of the scalp tends to metastasize to the lung, especially to the subpleural or surface pleural area and these metastatic tumours are prone to necrosis, causing characteristic pulmonary complications.

Aged↗
PubMed2002

Efficacy and tolerance of a scalp-cooling system for prevention of hair loss and the experience of breast cancer patients treated by adjuvant chemotherapy.

The applicability and efficacy of a scalp cooling system were studied in 105 breast cancer patients receiving four cycles of adjuvant chemotherapy with mitoxantrone + cyclophosphamide (NC chemotherapy). Women accepting the scalp-cooling system were compared for alopecia both against those who refused and against a "reference" group of 109 patients similarly treated but without being offered a scalp-cooling system. Hair loss in the 105 study patients was evaluated by nurses using World Health Organization (WHO) criteria at each cycle of chemotherapy. Concomitantly, tolerance and side-effects of the helmet were also recorded in 48 accepting patients. Similarly to reference group patients, a subsample of 27 accepting patients self-assessed hair loss using a specific questionnaire measuring its frequency and severity and the distress associated with this symptom. Nurses' ratings ( n = 105) indicated that hair loss frequency was constantly lower, at each cycle of chemotherapy, in study patients with scalp-cooling system ( n = 77) than in those without ( n = 28). Differences between the two groups were statistically significant at cycles 1 and 3 ( P < 0.05). When compared with those reported by reference group patients ( n = 109), study patients' self-measures of alopecia frequency ( n = 27) provided even more marked results than those achieved by nurses (cycles 1-3: P < 0.01; cycle 4: P < 0.05). Tolerance was generally good and no scalp metastasis was observed among the 77 accepting patients followed up. This study demonstrates that scalp cooling was an effective method of protection against hair loss caused by NC chemotherapy. Its routine use as part of adjuvant chemotherapy, especially in cancers with low prevalences of scalp metastasis, should be seriously considered.

Adult↗
PubMed1981

Scalp-recorded short latency cortical and subcortical somatosensory evoked potentials to peroneal nerve stimulation.

Short latency SEPs to peroneal nerve stimulation were recorded in 26 normal adults. These potentials consisted of 3 positive potentials (P1, P2, P3) peaking at about 17, 21 and 27 msec, followed by a negative potential (N1) peaking at about 34 msec. P1 and P2 were small and inconsistently recorded. P1 was widespread in its scalp distribution in non-cephalic reference leads, and was poorly defined or absent in scalp bipolar and ear reference leads. P2 was widespread in its scalp distribution in both non-cephalic and ear reference leads. It was poorly defined in scalp bipolar leads. P3 and N1 were consistently recorded from the scalp in both reference and bipolar leads. They were much greater in amplitude than the earlier potentials and had steep potential gradients. They were most prominent around the vertex. They showed significant differences in their peak latencies at different scalp recording locations. The short latency, positive polarity and widespread scalp distribution of P1 and P2 suggest they are far-field events arising in subcortical structures. The longer latency and steep potential gradient of P3 and N1 suggest that they are near-field events arising in cerebral cortical structures. Both P3 and N1 were stable potentials and, therefore, may prove to be clinically useful.

Adolescent↗
PubMed2005

Analysis of 197 female scalp tumors treated with Mohs micrographic surgery.

BACKGROUND: There has been no previously published study on skin cancers on the scalp of women. OBJECTIVES: To better elucidate the characteristics of skin cancers that develop on the female scalp. METHODS: A retrospective review of 13,885 biopsy-proven skin cancers treated by Mohs micrographic surgery was performed. We identified 197 tumors on the scalp of women. Demographic features and tumor characteristics were compiled and analyzed. RESULTS: The average age of women with scalp tumors was 61.8 +/- 16.9, which was significantly lower than that of men with scalp tumors. The age followed a bimodal distribution with peaks in the fifth and eighth decades. Overall, 77% of female scalp tumors were basal cell carcinomas (BCCs), 17% were squamous cell carcinomas (SCCs), and 6% were a variety of other tumors. This contrasts with men in whom 53% of tumors were squamous cell carcinomas. Basal cell carcinomas were significantly more common in women under age 50. CONCLUSION: Skin cancers of the female scalp tend to be basal cell carcinomas, many of which occur at a relatively young age as compared to other skin cancers. The exact role of ultraviolet radiation in the development of some of these tumors is unclear.

Adolescent↗
PubMed1998

Predictive agreement between the fetal arterial oxygen saturation and fetal scalp pH: results of the German multicenter study.

OBJECTIVE: To discuss and substantiate the 30% critical threshold of fetal arterial oxygen saturation and to complete the puzzle with low fetal arterial oxygen saturation and low scalp pH data, scalp samples have been performed while fetal arterial oxygen saturation registration during labor was in place and while the saturation was < or = 30%. STUDY DESIGN: Between 1993 and 1996, 46 term fetuses during active labor had parallel arterial oxygen saturation registration by pulse oximetry combined with cardiotocograph. They include patients in whom the saturation was < or = 30% for at least 10 minutes. In these cases scalp pH sample values have been obtained simultaneously. Outcome data, Apgar scores, cord gases, and whether the infants were transferred to the neonatal intensive care unit have been examined. Compared with this, there were other cases during labor that had also parallel fetal arterial oxygen saturation and cardiotocographic registration, where the saturation was > 30%. Also in these cases scalp pH was determined to support and demonstrate the predictive value of fetal arterial oxygen saturation for scalp pH, especially in the low ranges. All 46 fetuses were evaluated during periods of nonreassuring cardiotocograph with Nellcor N-400 Fetal Oxygen Saturation Monitoring Systems and FS 14 B sensors in a multicenter study involving three German obstetric centers. Receiver operating characteristic analysis was done on all raw data, as well as the receiver operating characteristic curve from the preceding analysis. RESULTS: These data validate the critical threshold of 30% fetal arterial oxygen saturation and show an extremely good separation of "good" versus "bad" at a fetal arterial oxygen saturation of 30%, especially when seen in conjunction with data points that are > 7.20. Data at < or = 7.20 scalp pH and < 30% fetal arterial oxygen saturation can be a big help in calculating the sensitivity and specificity of fetal arterial oxygen saturation in predicting neonatal outcome (e.g., Apgar score, cord pH). CONCLUSION: Low fetal arterial oxygen saturation data of < 30% for at least 10 minutes or longer correlate significantly with low scalp pH values and have a predictive value concerning fetal outcome.

Arteries↗
PubMed1997

A high resolution EEG method based on the correction of the surface Laplacian estimate for the subject's variable scalp thickness.

To improve the spatial resolution of human event-related potentials, we developed a new high resolution EEG method based on the improved estimate of the realistic surface Laplacian (SL). The novelty of this method consisted in the computation of the local scalp resistance that was assumed to be inversely proportional to the local scalp thickness measured from magnetic resonance images of the subject's head. The local scalp thickness was then multiplied by the SL estimate of the potential over a realistic magnetic resonance-constructed model of the subject's scalp surface. The new method was applied on human movement-related and somatosensory-evoked potentials, the SL estimate at a constant scalp thickness being used as a reference. The locally-predicted scalp thickness was significantly (P < 0.05) higher in the temporal areas (9.5 +/- 2.6 mm) than in the parieto-occipital (6.6 +/- 1.3 mm) and frontal (4.8 +/- 1.1 mm) areas. Compared to the SL estimate at constant scalp thickness, the improved SL estimate enhanced the spatial detail of both movement-related and somatosensory-evoked potentials.

Brain Mapping↗
PubMed1998

The scalp to earlobe montage as standard in routine SEP recording. Comparison with the non-cephalic reference in patients with lesions of the upper cervical cord.

We compared scalp somatosensory evoked potential (SEP) recordings by non-cephalic and earlobe reference in 14 healthy subjects and in 5 patients with lesions of the upper cervical cord. In healthy subjects, the scalp to earlobe montage tended to cancel all far-field potentials preceding the scalp P14. On the contrary, the P14 far-field was more difficult to identify in scalp to non-cephalic recordings, because in 12/14 cases it followed another far-field (P13), which was very close in latency to the P14. In 4 patients, the scalp to non-cephalic traces showed a single positive wave (P13/P14 complex) in the P14 latency range. If this complex had been labelled as P14, the somatosensory dysfunction would have been localised above the foramen magnum. On the other hand, the scalp to earlobe recording allowed correct localisation of the lesion since it showed the 'real' and delayed P14 in two patients and no far-field response in the remaining two. Therefore, we propose the use of the scalp to earlobe montage as standard in routine examinations.

Aged↗