Clinical Analysis of Laryngeal Trauma Secondary to Intubation

A study was undertaken to analyse the effect of short-term intubation on the voice. Children were examined laryngographically both pre- and postoperatively. Changes in larynx frequency distribution following intubation were documented using the technique of electrolaryngography; the resolution of these changes was similarly recorded. The results, in comparison with the frequency distributions associated with other disease states, give insight into the nature of the damage and its effect on vocal fold vibratory patterns. The technique therefore enables objective evidence of minor degrees of laryngeal trauma to be demonstrated and differentiated.

Classification and management of cervical paragangliomas

INTRODUCTION

Cervical paragangliomas are slow-growing tumours that eventually cause lower cranial nerve palsies and infiltrate the skull base. Surgical treatment may cause the same deficits and, in some, risks more serious neurological deficits. We describe a classification used to guide investigation, consent and management of cervical paragangliomas based on extensive experience.

METHODS

The case notes of patients managed by the senior author at a tertiary referral skull base unit between 1987 and 2010 were reviewed retrospectively. A total of 87 cervical paragangliomas were identified in 70 patients (mean age: 46 years, range: 13-77 years). Of these, 35 patients had 36 vagal paragangliomas, 43 patients had 50 carotid body paragangliomas and 8 had both. One cervical paraganglioma arose from neither the carotid body nor the nodose ganglion. The main outcome measures were death, stroke, gastrostomy and tracheotomy.

RESULTS

All tumours were classified pre-operatively based on their relationship to the carotid artery, skull base and lower cranial nerves. Type 1 tumours were excised with a transcervical approach, type 2 with a transcervical-parotid approach and type 3 with a combined transcervical-parotid and infratemporal fossa approach. Type 4 patients underwent careful assessment and genetic counselling before any treatment was undertaken. There were no peri-operative deaths; two patients had strokes, one required a long-term feeding gastrostomy and none required a tracheotomy.

CONCLUSIONS

The use of a pre-operative classification system guides management and surgical approach, improves accuracy of consent, facilitates audit and clarifies which patients should be referred to specialised centres.

The relationship between pure tone thresholds and the radiological dimensions of acoustic neuromas

A retrospective analysis of 109 consecutive patients presenting with acoustic neuromas between 1986 and 1997 were undertaken. Sufficient data were available in 104 cases for comparison. In 65 cases patients had undergone surgery and the radiological diagnosis of acoustic neuroma was confirmed histologically. In this group there were 25 large and 40 small tumors when a maximal radiological diameter of 2.5 cm was used to subdivide the groups. When pure tone thresholds were compared at specific frequencies, in those with hearing ears, there was no significant difference between the two groups. Our results are compared with recent series and the causes of hearing loss associated with acoustic neuroma are discussed.

Prediction of facial nerve function after surgery for cerebellopontine angle tumors: use of a facial nerve stimulator and monitor

A series of 18 patients undergoing surgery for cerebellopontine angle tumors is reported. Patients were grouped according to size of tumor (0 to 2.5 cm, 11 cases; more than 2.5 cm, 7 cases). In all, the facial nerve was identified and conductance assessed by monitoring the facial electromyographic response to facial nerve stimulation. Postoperative facial nerve function was graded clinically after 3 months according to the House scale. Tumor removal was complete in all cases. In patients with tumors up to 2.5 cm the facial nerve was intact to visual inspection at the end of the procedure in all but one, where partial division was evident. In this group intraoperative facial nerve stimulation indicated electrical integrity in 8 of the 11 cases, all of which regained good facial nerve function postoperatively (House grades I and II). Nerve conduction was lost during the operation in the remaining three patients with small tumors; two subsequently developed a moderately severe (grade IV) dysfunction and the third, a total paralysis (grade VI). In the large (more than 2.5 cm) tumor group the facial nerve was anatomically intact in five of the seven cases, partially divided in one, and completely sectioned in the remaining case. Facial nerve stimulation indicated functional integrity in three patients, two of whom developed moderate (grade III) and the third a severe (grade V) dysfunction. In the other four cases nerve function could not be detected at operation; three of these developed a moderate facial nerve dysfunction (grade III/IV) and the final case a complete paralysis (grade VI). Intraoperative facial nerve monitoring appeared to predict eventual facial function accurately in the small tumor group, but did not predict facial nerve recovery reliably following surgery for larger tumors.

Extracranial glomus faciale tumour

Objectives:

To describe a unique presentation of a predominantly extracranial glomus faciale tumour. To discuss the role of imaging in the differential diagnosis and evaluation of a hypervascular parotid mass. To review the previous literature concerning the glomus faciale tumour.

Case report:

A 54-year-old woman presented with a six-month history of facial weakness, pain and a parotid mass. Ultrasound revealed a hypervascular parotid mass and pre-operative core biopsy suggested a paraganglioma. Computed tomography defined its deep extent and demonstrated involvement of the petrous temporal bone along the descending portion of the facial nerve canal with a pattern of permeative lucency. A tumour was surgically removed which arose from the facial nerve from the second genu to the proximal divisions within the parotid gland and histology confirmed a paraganglioma.

Conclusions:

A facial nerve glomus faciale tumour should be considered in the differential diagnosis of a hypervascular parotid mass and may present in a predominantly extracranial location. Computed tomography will prove helpful in such a case in order to limit the differential diagnosis and to define the extent of skull base involvement.

Mesotympanic sarcoidosis

Sarcoidosis often presents with signs and symptoms within the head and neck. In this region, it most commonly affects the nose, larynx, parotid and cervical lymph nodes. Within the ear, it usually causes sensorineural hearing loss of varying severity. We report a patient in whom sarcoidosis involved the middle ear and presented with a conductive hearing loss. Granulomata were found in the middle ear during an exploratory tympanotomy. The granulomatous process had caused necrosis of the long process of incus and was also encasing the chorda tympani nerve. Histological examination confirmed the diagnosis.

Accumulation of Krebs cycle intermediates and over-expression of HIF1alpha in tumours which result from germline FH and SDH mutations

The nuclear-encoded Krebs cycle enzymes, fumarate hydratase (FH) and succinate dehydrogenase (SDHB, -C and -D), act as tumour suppressors. Germline mutations in FH predispose individuals to leiomyomas and renal cell cancer (HLRCC), whereas mutations in SDH cause paragangliomas and phaeochromocytomas (HPGL). In this study, we have shown that FH-deficient cells and tumours accumulate fumarate and, to a lesser extent, succinate. SDH-deficient tumours principally accumulate succinate. In situ analyses showed that these tumours also have over-expression of hypoxia-inducible factor 1alpha (HIF1alpha), activation of HIF1alphatargets (such as vascular endothelial growth factor) and high microvessel density. We found no evidence of increased reactive oxygen species in our cells. Our data provide in vivo evidence to support the hypothesis that increased succinate and/or fumarate causes stabilization of HIF1alpha a plausible mechanism, inhibition of HIF prolyl hydroxylases, has previously been suggested by in vitro studies. The basic mechanism of tumorigenesis in HPGL and HLRCC is likely to be pseudo-hypoxic drive, just as it is in von Hippel-Lindau syndrome.

Congenital sialolipoma of the parotid gland first reported case and review of the literature

Tumours of the parotid gland in children are uncommon, and represent only 1.3% of all benign salivary tumours. Lipomas of the parotid are also rare, and account for 0.5% of all parotid gland tumours. Sialolipoma is a new variant of salivary gland lipoma, consisting of adipose and glandular tissue that was first proposed by Nagao et al. in 2001. Ten cases of parotid gland lipoma associated with glandular elements have been previously reported in the literature. All have been in adults and none in children. We present the first reported case of congenital sialolipoma that had developed in a female infant. It was managed successfully by superficial parotidectomy undertaken at ten weeks of age.

3-D optical coherence tomography of the laryngeal mucosa*

Laryngeal carcinoma is one of the commonest primary head and neck malignancy and the need for early identification is very important for successful treatment. Outpatient fibreoptic examination of the larynx is unreliable in differentiating benign, pre-malignant and malignant lesions, and therefore surgeons have to rely on biopsies for a definitive diagnosis. This is an invasive procedure requiring general anaesthesia and may have a detrimental effect on the patient's voice. Conventional imaging modalities (ultrasound, computed tomography and magnetic resonance imaging) have a limited resolution and hence cannot give sufficient information on the extent or nature of laryngeal lesions. The aim of our study is to investigate the feasibility of optical coherence tomography (OCT) in imaging the normal larynx, to lay the foundations for an investigation of its ability to differentiate between benign and malignant disease. Ten tissue specimens from normal larynges were imaged with an 850 nm OCT system that was capable of providing both B-scan (longitudinal or cross-section) images as well as C-scan (en-face or images at constant depth). The en-face OCT mode allowed us to reconstruct 3-D OCT images of the tissue examined. Imaged specimens were processed with standard histopathological techniques and sectioned in the plane of the B-scan OCT images. Haematoxylin-eosin stained specimens were compared with the OCT images thus collected. Preliminary results showed good correlation between OCT images and histology sections in normal tissue.

Quality of life following microsurgery, radiosurgery and conservative management for unilateral vestibular schwannoma

The best way to manage small and medium-sized vestibular schwannomas is currently a matter of heated debate. As these tumours are not immediately life-threatening, patients are invariably concerned about how management would affect their quality of life. Until now, no study has compared the three treatment modalities in terms of physical, psychological and social wellbeing. This study is based on a retrospective database analysis and postal questionnaire survey of unilateral vestibular schwannoma patients who had either been managed conservatively, or treated with microsurgery or radiosurgery. The results showed that: quality of life (measured by the Glasgow Benefit Inventory) deteriorated after microsurgery, particularly for small tumours; conservative management did not lead to a change in quality of life, and there was a trend towards poorer quality of life following radiosurgery. The findings suggest that a conservative management approach may be more appropriate for small tumours, and that patients who are due to undergo microsurgery or radiosurgery may benefit from counselling about the potential impact of treatment on quality of life.

Stereo augmented reality in the surgical microscope

We present an augmented reality system that allows surgeons to view features from preoperative radiological images accurately overlaid in stereo in the optical path of a surgical microscope. The purpose of the system is to show the surgeon structures beneath the viewed surface in the correct 3-D position. The technical challenges are registration, tracking, calibration and visualisation. For patient registration, or alignment to preoperative images, we use bone-implanted markers and a dental splint is used for patient tracking. Both microscope and patient are tracked by an optical localiser. Calibration uses an accurately manufactured object with high contrast circular markers which are identified automatically. All ten camera parameters are modelled as a bivariate polynomial function of zoom and focus. The overall system has a theoretical overlay accuracy of better than 1 mm. Implementations of the system have been tested on seven patients. Recent measurements in the operating room conformed to our accuracy predictions. For visualisation the system has been implemented on a graphics workstation to enable high frame rates with a variety of rendering schemes. Several issues of 3-D depth perception remain unsolved, but early results suggest that perception of structures in the correct 3-D position beneath the viewed surface is possible.

Design and evaluation of a system for microscope-assisted guided interventions (MAGI)

The problem of providing surgical navigation using image overlays on the operative scene can be split into four main tasks--calibration of the optical system; registration of preoperative images to the patient; system and patient tracking, and display using a suitable visualization scheme. To achieve a convincing result in the magnified microscope view a very high alignment accuracy is required. We have simulated an entire image overlay system to establish the most significant sources of error and improved each of the stages involved. The microscope calibration process has been automated. We have introduced bone-implanted markers for registration and incorporated a locking acrylic dental stent (LADS) for patient tracking. The LADS can also provide a less-invasive registration device with mean target error of 0.7 mm in volunteer experiments. These improvements have significantly increased the alignment accuracy of our overlays. Phantom accuracy is 0.3-0.5 mm and clinical overlay errors were 0.5-1.0 mm on the bone fiducials and 0.5-4 mm on target structures. We have improved the graphical representation of the stereo overlays. The resulting system provides three-dimensional surgical navigation for microscope-assisted guided interventions (MAGI).

Mycobacterial disease of the parotid gland

Mycobacterial disease is an unusual but important condition that should be considered in the differential diagnosis of a discrete parotid gland swelling or mass. The management of this condition involves exclusion of neoplastic disease and combined medical and surgical therapy. We present 5 cases of mycobacterial involvement of the parotid gland and discuss issues surrounding the diagnosis and treatment options.

A system for microscope-assisted guided interventions

We present a system for surgical navigation using stereo overlays in the operating microscope aligned to the operative scene. This augmented reality system provides 3D information about nearby structures and offers a significant advancement over pointer-based guidance, which provides only the location of one point and requires the surgeon to look away from the operative scene. With a previous version of this system, we demonstrated feasibility, but it became clear that to achieve convincing guidance through the magnified microscope view, a very high alignment accuracy was required. We have made progress with several aspects of the system, including automated calibration, error simulation, bone-implanted fiducials and a dental attachment for tracking. We have performed experiments to establish the visual display parameters required to perceive overlaid structures beneath the operative surface. Easy perception of real and virtual structures with the correct transparency has been demonstrated in a laboratory and through the microscope. The result is a system with a predicted accuracy of 0.9 mm and phantom errors of 0.5 mm. In clinical practice errors are 0.5-1.5 mm, rising to 2-4 mm when brain deformation occurs.

Feasibility study of magnetic resonance imaging-guided intranasal flexible microendoscopy

Interventional magnetic resonance imaging (MRI) offers potential advantages over conventional interventional modalities such as X-ray fluoroscopy, ultrasonography, and computed tomography (CT). In particular, it does not use ionizing radiation, can provide high-quality images, and allows acquisition of oblique sections. We have carried out a feasibility study on the use of interventional MRI to track a flexible microendoscope in the paranasal sinuses. In this cadaver study, high-speed MRI was used to track a passive marker attached to the end of the endoscope. Automatic image registration algorithms were used to transfer the coordinates of the endoscope tip into the preoperative MRI and CT images, enabling us to display the position of the endoscope in reformatted orthogonal views or in a rendered view of the preoperative images. The endoscope video images were digitized and could be displayed alongside an approximately aligned, rendered preoperative image. Intraoperative display was provided in the scanner room by means of an liquid crystal display (LCD) projector. We estimate the accuracy of the endoscope tracking to be approximately 2 mm.

Malignant vagal paraganglioma

Vagal paraganglioma is a rare usually benign tumour of neural crest origin. The malignant form of this tumour is very uncommon and the diagnosis is made on the basis of its clinical behaviour rather than its histological appearance. We report a case of vagal paraganglioma metastatic to adjacent cervical nodes and discuss the diagnosis and management of this tumour.

Solitary infantile and adult myofibromatosis of the nasal cavity: a report of two cases

Myofibromatosis is an uncommon, usually cutaneous, condition in which there is a benign proliferation of myofibroblasts. Solitary and multicentric nodular forms with, and without, visceral involvement have been described. Infantile and adult sub-types have been reported, each having distinct clinicopathological features. Presentation in the head and neck is common. It is frequently misdiagnosed because of its peculiar histological features. The first documented cases of infantile and adult myofibromatosis involving the nasal cavity are reported.

Expression of adhesion molecules on the microvasculature of the pharyngeal tonsil (adenoid)

We have examined the vasculature of 12 human adenoids and the expression and distribution of four endothelial adhesion molecules, ICAM-1, VCAM-1, P-selectin and E-selectin, in tissue sections using histology, immunocytochemistry and immunoelectron microscopy (IEM). The connective tissue septa and septula contained arterioles, veins and efferent lymphatics. Branches of arterioles supplied lymphoid follicles and divided into sub- and intraepithelial capillary plexuses which drained into interfollicular venules, mostly high endothelial venules (HEV), before joining larger veins. No afferent lymphatics were observed entering the adenoid. Although ICAM-1 was widely distributed in the tissue, it was preferentially expressed on luminal aspects of HEV. E-selectin was found only in a few areas on HEV and subepithelial capillaries, whereas P-selectin was strongly expressed on segments of HEV, adjacent small venules and a few follicular capillaries. IEM showed the localisation of VCAM-1 on the components of the perivascular sheath, but not on the endothelium, of some HEV and capillaries. Its strongest expression was on follicular dendritic cells (FDC). These findings showed that in addition to HEV, lymphocyte-binding molecules are expressed on other segments of adenoid vasculature and their distribution and intensity of expression varies. In the non-inflamed adenoid, the VCAM-1 does not seem to participate in the adhesive mechanism of recirculating lymphocytes to the endothelium which, in this study, lacked the expression of VCAM-1 in all vessels.

Bomb blast injuries to the ear: the London Bridge incident series

Twelve patients who were treated for ear injuries at Guy's Hospital following the London Bridge bomb blast in February 1992 were reviewed. Among three there were four perforated eardrums, two of which closed spontaneously (50%). All three patients had a persistent mixed hearing loss. The remaining nine patients had acute sensorineural hearing loss and/or tinnitus only. Four of these had resolved completely by 4h, another one by 48h, and two by 4 weeks. Two patients had a residual high frequency hearing loss. In total, five patients (42%) have a persistent hearing loss. None of the patients suffered from balance problems. In summary, the ear is very susceptible to bomb blast injury, but there is a high rate of spontaneous closure of perforations and improvement of sensorineural hearing loss and tinnitus.

Renal transplantation in patients with spina bifida

OBJECTIVES

Renal transplantation in patients with spina bifida is not commonly performed, although these patients have a high incidence of end-stage renal disease.

METHODS

Between February 1989 and December 1991, we performed 5 cadaveric renal transplants in 4 patients with spina bifida. There were 3 male patients and 1 female patient with a mean age of 22.5 years (range, 10 to 36 years). All patients had lumbar myelomeningoceles repaired shortly after birth. Three patients were wheelchair-bound due to their neurologic deficit. Prior to renal transplantation, management of neuropathic bladder dysfunction consisted of ileal conduit (1 patient), "clam" cystoplasty with clean intermittent self-catheterization (CISC; 1 patient), and CISC alone (2 patients).

RESULTS

In this series, 1 patient died of fungal septicemia 6 weeks postoperatively. One patient underwent transplantation again following primary nonfunction of his original allograft. Serum creatinine levels were 56, 91, and 120 mmol/L, respectively, after 18 months' follow-up.

CONCLUSIONS

This article demonstrates the feasibility of cadaveric renal transplantation in selected patients with end-stage renal failure and spina bifida. We currently recommend that these patients not be excluded from gaining the benefits of renal transplantation.

Combined and three-dimensional rendered multimodal data for planning cranial base surgery: a prospective evaluation

Magnetic resonance (MR), X-ray computed tomography (CT), and angiographic images best depict soft tissue, bone, and blood vessels respectively. No one on its own is sufficient in the preoperative assessment of cranial base lesions. We have developed and evaluated a computational technique for the three-dimensional (3D) combination and display of multimodality images for planning cranial base surgery. This evaluation was prospective and performed in such a way that the results could be quantified. Eight patients (three acoustic neuromas, four subfrontal and suprasellar meningiomas, and one petrous apex meningioma) underwent MR, CT, and MR angiographic investigations. These images were registered with anatomical landmarks rather than an external frame. Two techniques were used to display the resulting combined images: multiple slices in which bone from CT was overlaid on soft tissue from registered MR and pseudo-3D-rendered movie sequences showing bone from CT, lesions and optic nerves from MR, and blood vessels from MR angiography. The advantages of the combined displays compared with those of conventional methods of viewing were assessed prospectively by the operating surgeon and by an independent surgeon, and the results were compared with operative findings. The preoperative assessment showed a significant improvement (P < 0.05, sign test) in the depiction of both individual structures (lesion and bone from overlaid slices and lesion and vasculature from 3D-rendered displays) and structural relationships (tumor-bone relationships from overlaid slices and of tumor-vasculature relationships from 3D-rendered displays). The operative findings indicated that a more accurate interpretation of this information was possible from the combined images.

Angioedema secondary to angiotensin-converting enzyme inhibitors

Angioedema secondary to angiotensin-converting enzyme (ACE) inhibitors is rare, but it is a side effect which is likely to be seen more frequently because of the increased use of these drugs to treat cardiac failure and hypertension. Presentation is variable and the diagnosis may go unrecognized for many months or years. The cases reported illustrate problems both in the diagnosis and management of this life-threatening condition.

Accurate frameless registration of MR and CT images of the head: applications in planning surgery and radiation therapy

PURPOSE

To evaluate the feasibility and efficacy of a three-dimensional image registration technique for planning skull base surgery, performing frameless image registration for stereotaxic neurosurgery, and staging nasopharyngeal carcinoma.

MATERIALS AND METHODS

Computed tomographic (CT) and magnetic resonance (MR) images from 35 patients were registered by identifying 12-16 homologous landmarks with each modality. Images were displayed as overlaid sections or rendered three-dimensional scenes. The clarity of the combined images from 15 patients undergoing skull base surgery was compared with that of the conventional displays.

RESULTS

Images were combined for three applications, with an accuracy of 1-2 mm. For the 15 patients undergoing skull base surgery, the combined images were significantly better at depicting the relationship between bone and lesion than conventional display (P < .01).

CONCLUSION

MR and CT images of the head can be accurately registered without using external markers or substantially altering image acquisition protocols. The resulting images can show the radiologic information more clearly than conventional viewing.

Comparison of reagent strip (dipstick) and microscopic haematuria in urological out-patients

Dipstick (reagent strip) and microscopic urine analysis for haematuria was performed prospectively on 1000 consecutive urine samples taken from urological out-patients. Haematuria was present in 185 samples (18.5%) and absent in 687 (68.7%) using both tests; 98 samples (9.8%) had dipstick haematuria that was not confirmed by microscopy and 30 samples (3%) had microscopic haematuria that was missed on dipstick urine analysis. Dipstick urine analysis had a sensitivity of 86.1% and a specificity of 85%. This study confirms that reagent strip testing for haematuria has both false positive and false negative results and indicates that cytoscopy should be considered in all patients with suspected haematuria.

Morphological features of human Reissner's membrane

Light and electromicroscopic investigations of Reissner's membrane were undertaken on 10 cochleae from 6 patients with normal hearing for their age. The membrane consisted of two layers, an epithelium and a mesothelium separated by a basement membrane. The mesothelium was formed by a single thin layer which was intermittently discontinuous. The melanocytes were localized on the mesothelial side of the basement membrane. Their numbers was 2-4 times greater in the upper half of the basal turn and in the middle turn than elsewhere. The epithelium was much thicker and had more irregular features than the mesothelium. It was composed of two types of epithelial cells, flat and rounded. The flat cells were more regular in shape than the rounded cells and they were mainly distributed in the middle and apical turns. Judging from their structure they were in a resting state. The rounded cells covered a smaller area than the flat ones and had numerous microvilli. They assumed three different shapes, cuboidal, spindle-form and spherical and were arranged in four different patterns, namely bands, strands, whorls and clusters. The rounded cells were the most active according to the composition of the cytoplasm and dominated the cell population in the hook and the lower half of the basal turn where the age-related sensorineural degeneration is most apparent.

Tissue-bonded iontophoretic cystostomy: conceptual and experimental considerations

We describe a conceptual model for drainage of the dysfunctional bladder. Experimental data from investigations involving several species of animals are presented to support the hypothesis that mature tissue-bonded alloplastic tubes drain urine effectively and are tolerant and resistant to endogenous and exogenous bacteria. We conclude that preliminary clinical trials of a tissue-bonded cystostomy are warranted. We postulate that success in these trials may offer a new alternative for the management of severe vesical dysfunction.

Human Reissner's membrane in patients with age-related normal hearing and with sensorineural hearing loss

Morphological features of Reissner's membrane were investigated in 6 patients with age-related normal hearing (ARNH) and in 4 with sensorineural hearing loss (SNHL) stemming from various causes. The membrane consisted of an epithelium, a basement membrane and a mesothelium with melanocytes. There were two major forms of epithelial cells: flat and rounded. In all specimens, the rounded cells formed whorls, clusters, strands and bands. The bands were wider and the whorls larger in the basal turn and decreased gradually in size toward the apex. The number of melanocytes was 2-4 times higher in both the upper half of the basal turn and the lower half of the middle turn than in the rest of the turns. In specimens from patients with SNHL, whorls and clusters were both more numerous and larger, and the number of melanocytes was higher in the upper half of the middle turn and in the apical turn than that in the ARNH group. Ultrastructural examination of epithelial and mesothelial cells as well as of melanocytes showed more pronounced cellular degeneration in patients with SNHL than in those with ARNH. A possible correlation between structural alterations of Reissner's membrane and sensorineural degeneration is discussed.

Is retrograde ureterography indicated in pelviureteric junction obstruction?

The role of retrograde ureterography in the management of pelviureteric junction (PUJ) obstruction remains controversial and it has recently been reiterated that visualisation of the entire ureter on the affected side is mandatory owing to the high incidence of other ureteric abnormalities. In a review of 119 consecutive adult pyeloplasties carried out over a 9-year period, only 2 ureteric abnormalities were found in association with PUJ obstruction (duplex ureter/3-cm proximal stricture). Other anatomical abnormalities included aberrant vessels, fascial bands and renal anomalies. Most secondary abnormalities were undiagnosed prior to surgery and all were easily dealt with per-operatively.

Acoustic tumour volume and the prediction of facial nerve functional outcome from intraoperative monitoring

The long-term facial function in 26 patients undergoing surgery to remove an acoustic neuroma has been related to the tumour volume (ml) estimated by computerized tomogram (CT) reconstruction techniques. Analysis of data allowed accurate categorization into 'small' (= < 5 ml) and 'large' (> 5 ml) tumours, which gave the maximum prognostic distinction between two groups for facial recovery. Thus, of the 14 patients with small volume tumours, 11 achieved a good (House grade I or II) facial outcome compared with 1 out of 12 patients with large tumours. Combined with the information derived from the assessment of intraoperative facial nerve electrical integrity using a combined nerve stimulator and EMG monitor, long-term facial function was predictable for all small tumours defined by volume. This represented a 15% improvement in prediction of facial recovery when defining tumour size by maximum linear dimension (small = < 2.5 cm, large > 2.5 cm). The calculations of volume obtained using a simplified ellipsoidal model compared well with CT reconstructed values (r2 = 0.85), and gave identical prediction and outcome comparisons.

A comparative study of calcium sodium alginate (Kaltostat) and bismuth tribromophenate (Xeroform) packing in the management of epistaxis

A prospective study was undertaken to compare the efficacy of calcium sodium alginate fibre (Kaltostat) to petrolatum gauze impregnated with bismuth tribromophenate (Xeroform) for the control of epistaxes that require hospital admission. Forty patients presenting with severe epistaxis requring hospital admission were treated with either Kaltostat or Xeroform nasal packs. Allocation to either treatment group was made randomly. The composition of each group in terms of age, sex distribution, aetiology of epistaxis and severity of bleed was not significantly different. There was no significant difference in the efficacy or patient acceptability of either therapeutic agent. It is concluded that calcium sodium alginate fibre should be considered as an acceptable alternative to traditional gauze packing.

Antroconchopexy for surgical treatment of perennial rhinitis

We report on a rhinomanometric assessment of eleven patients undergoing antroconchopexy for relief of a "stuffy" nose. This little-known procedure involves the lateralization of the inferior turbinate through a large intranasal antrostomy. Our results demonstrate a significant improvement in postoperative inspiratory and expiratory nasal resistance. There was also a significant improvement in patient's scoring for nasal obstruction. Finer points of the surgical technique, and indications for the procedure are discussed.

Magnetic resonance imaging of the parotid gland using the STIR sequence

The object of this study was to determine the efficiency of the short tau inversion recovery (STIR) sequence in the assessment of salivary disease. Sixteen patients with tumours either in or adjacent to the parotid gland were imaged using a 1.5T Philips Gyroscan, with a standard head coil. T1-weighted spin-echo and STIR sequences were obtained in multiple planes and assessed independently by each of the authors. Positive fine needle aspiration cytology or histological proof of the nature of the imaged lesions was obtained for every patient. T1-weighted spin-echo images were most useful for visualizing anatomical structures and for identification of the facial nerve. All lesions were visible with T1-weighted images but were very much more conspicuous in the STIR sequences, for which a minimal lesion resolution of 6 mm was achieved. No contrast enhancement was required. It was not possible to determine the pathological nature of the lesion by scan appearance only. Our conclusion is that a combination of T1-weighted spin-echo and STIR sequences in the axial and coronal planes is the preferred protocol for salivary gland imaging.

Morphometric analysis of the cochlear nerve in man

Fiber diameters were analyzed in the meatal segment of the cochlear nerve from 7 temporal bones obtained from 7 patients. Two patients had normal hearing for their age. Two had sustained noise exposure and one had presbyacusis of predominantly neural type. The cochleae displayed characteristic degeneration patterns. The other two manifested hearing loss of unspecified type. The fiber diameters ranged from 0.5 to 11 microns. The diameter distribution was unimodal in all seven nerves. The means of the diameters ranged from 4.2 to 5.5 microns. They were significantly different between patients with age-related normal hearing on the one hand and patients with noise induced hearing loss and neural presbyacusis on the other. The findings are discussed in relation to changes in nerve conduction speed and hearing loss; a possible correlation between the fiber diameter distribution and the tonotopical arrangement of the cochlea is suggested.

Registration of MR and CT images for skull base surgery using point-like anatomical features

We have developed a registration technique for combining magnetic resonance imaging (MRI) and computed tomography (CT) images of the skull base for use in surgical planning. The technique is based on user identification of point-like landmarks visible in both modalities. The combination of images involves a small amount of expert interaction, is relatively quick and preliminary evaluation indicates that it is accurate to within 1.5 mm. Registered or fused images can be viewed either on an image processing workstation, or fused images can be printed onto conventional film for convenience in clinical use. We present one patient in order to demonstrate the technique's indications and advantages.

Randomized, double-blind trial of Lithostat (acetohydroxamic acid) in the palliative treatment of infection-induced urinary calculi

In a prospective, double-blind, placebo-controlled study, the efficacy and safety of acetohydroxamic acid (AHA) in preventing urinary calculogenesis was evaluated in 94 patients with chronic urinary infection. Stone growth occurred in 17% of the AHA group and in 46% of the placebo group (p less than 0.005). Completely reversible side effects consisting predominantly of psychoneurologic and musculo-integumentary symptoms were more prevalent in the AHA group (p less than 0.01). Side effects which were judged 'intolerable' were experienced by 10 (22.2%) of patients in the AHA group and 2 (4.1%) in the placebo group. It is concluded that AHA treatment is effective, relatively safe, and clinically useful in preventing infection-induced urinary calculogenesis.

Percutaneous endoscopic treatment of cholelithiasis

Surgical management of gallstones was first performed successfully in 1878. Over the past decade, several new treatment alternatives have evolved that challenge the supremacy of traditional surgical cholecystectomy. Two endoscopic alternatives, e.g., percutaneous cholecystolithotomy (PCCL) and laparoscopic cholecystectomy (LC) are the latest additions to the growing armamentarium. Our initial experience with PCCL and LC as compared with our traditional cholecystectomy experience shows a 57% reduction in hospital days, a 58% reduction in postoperative analgesic dose, and 50% or more reduction in disabling convalescence in favor of the endoscopic alternatives. A review of the efficacy and morbidity of traditional surgery, peroral drug chemolysis (PDC), shockwave lithotripsy plus PDC, and percutaneous transhepatic lavage with methyl terbutyl ether suggests that the endoscopic alternatives are less morbid than traditional surgery and more efficacious and perhaps less morbid than other non-invasive or minimally invasive alternatives. Both original data and a literature review are presented.

Percutaneous cholecystolithotomy. A minimally invasive alternative to cholecystectomy and to shock wave lithotripsy

Recently introduced treatment alternatives for gallstones include peroral pharmacological chemolysis plus shock wave lithotripsy and percutaneous cholecystolithotomy. Herein we report on the treatment preferences of 23 patients with symptomatic gallstones and our initial experience with percutaneous cholecystolithotomy in 6 of these patients. All patients were rendered stone free after one procedure. Percutaneous cholecystolithotomy, which is applicable to all types of gallstones, is a safe, practical, low-morbidity alternative to cholecystectomy in selected patients.