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.

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.

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.

Effectiveness of radiation control program for Dornier HM3 lithotriptor.

Radiation exposure during extracorporeal shock-wave lithotripsy (ESWL) was calculated using a "worst-case method" in 135 randomly selected patients. The patients were divided into four groups according to body weight: small (less than 140 pounds), medium (141-180 pounds), large (181-220 pounds), and very large (greater than 220 pounds). Average skin exposure was found to be 15.2 R (from 1.2 to 95.6 R). After implementation of a "radiation awareness program" radiation exposure was calculated in 128 cases (matched for body weight and stone burden) and average exposure was 9.5 R (from 0.9 to 33.4 R) with a reduction of 20, 37, 33, and 62 percent for each group, respectively. Radiation exposure reduction was primarily due to a reduction in the number of radiographic "snapshots" taken as a result of preferential use of special-mode fluoroscopic "stills."

Effect of unprocessed wheat bran on calciuria and oxaluria in patients with urolithiasis.

Seventeen hypercalciuria patients (8 control, 9 treatment) with a history of urolithiasis were randomly selected to receive low-calcium, low-oxalate diets with or without the addition of 30 g of dietary fiber as unprocessed wheat bran. Diet alone resulted in a 5.6 percent decrease in calciuria compared with a 23.5 percent decrease with the addition of the fiber. The addition of hydrochlorothiazide and potassium citrate further reduced calciuria by 40.4 percent and 34.5 percent, respectively. Oxaluria was decreased 21.4 percent by diet alone compared with 3.9 percent in the diet and fiber treatment group. Patient compliance to diets was good, and no complications resulted from fiber intake.

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.

The benefits of stenting on a more-or-less routine basis prior to extracorporeal shock-wave lithotripsy.

Indwelling internal ureteral stents are helpful in minimizing the morbidity of ESWL for large renal stones. Soft silicone stents are well tolerated. A pull-out suture allows convenient removal of the stent without cystoscopy.

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.

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).

Comparison of oscillation with three other methods for measuring nasal airways resistance.

In this study we have compared the sensitivity and reproducibility of nasal airways resistance measurements made using an oscillometer, with those made by passive anterior, active anterior and active posterior rhinomanometry. Nasal airways resistance values were compared in 12 patients with rhinitis and 15 normal subjects, of whom ten had additional measurements after a vasoconstrictor spray, oxymetazoline. The coefficients of variation of 6-8 technically satisfactory measurements were 9-19%. The decongestant effect of oxymetazoline was detected by all methods, with no decrease in reproducibility. Post vasoconstrictor nasal airways resistance fell by 28% (passive anterior), 35% (active anterior), 36% (active posterior) and 58% (oscillometry). In conclusion, the oscillation method for deriving nasal airways resistance is a useful, new, simple and noninvasive way of assessing nasal airways patency. Results compare favourably with other, more established techniques.

A morphological study of the effect of the Cavitron ultrasonic surgical aspirator system near human peripheral nerves.

The Cavitron ultrasonic surgical aspirator system was used to clear superficial tissue from the greater auricular nerve in four human subjects. Following stimulation, the nerves were removed together with an untreated section and processed for examination by light microscopy. Significant damage had been sustained by these nerves, which was not apparent in the control sections. Disruption of the perineurium, intraneural hemorrhage, endoneural edema, and degenerative changes of the myelinated nerve fibers were seen. Damage to neural tissue was evident 0.5 to 1.5 mm in advance of the point of contact with the cutting tip.

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.

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.

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 scanning electron microscopy study of post mortem autolytic changes in the human and rat cochleas.

The use of SEM as an adjunct to TEM and electrophysiological examination of the cochlea is now well established. It has provided a relatively simple method of assessing the effect of noise, ototoxic drugs, electrical stimulation, etc. on the surface features of the organ of corti. A controlled experiment was undertaken to document the surface autolytic changes in rat cochleas by fixation at intervals up to eight hours post mortem. These were compared with human material fixed between 40 minutes and eight hours post mortem. The results complement previous light and transmission electron microscopy studies, gives insight into the optimal and acceptable fixation times for the two species and act as a guide for the interpretation of human material.

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.

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.

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.

Post-tonsillectomy secondary haemorrhage.

This paper compares the incidence of secondary haemorrhage in post-tonsillectomy patients who were discharged 48 hours after operation (2.8%) with those discharged at 24 hours (3%). There was no significant difference between the groups. A higher incidence of secondary haemorrhage in those patients in whom diathermy was used for haemostasis rather than ligatures (P less than 0.01) supports previous studies.