Endoscopic transnasal image-guided approach to diagnosis in orbital apex and optic canal lesions.

OBJECTIVE: Prompted by a recurring skull base multidisciplinary team debate on the necessity of securing a definitive tissue diagnosis before initiating treatment for lesions of the orbital apex, a review of anterior skull base procedures over an 11-year period was undertaken. METHODS: Data collected prospectively on cases from 2006 to 2017 were analysed. Presenting symptoms, imaging and histology findings, outcomes, complications, and impact on treatment were evaluated. All surgery was carried out endoscopically with the aid of image guidance. RESULTS: Twenty-one patients undergoing endoscopic orbital apex and/or optic canal biopsy were included. The mean patient age was 49 years. Five malignant tumours were identified, five benign tumours, seven infective cases (two tuberculosis and five fungal) and two cases of immunoglobulin G4 related disease. Two patients had non-diagnostic biopsies (one lesional) and were treated successfully as Tolosa-Hunt syndrome cases. CONCLUSION: A successful diagnosis was achieved in nearly all cases without adverse impact, other than one cerebrospinal fluid leakage case. Management was directly influenced by the outcome in all cases.

Forensic Entomology: Evaluating Uncertainty Associated With Postmortem Interval (PMI) Estimates With Ecological Models.

Estimates of insect age can be informative in death investigations and, when certain assumptions are met, can be useful for estimating the postmortem interval (PMI). Currently, the accuracy and precision of PMI estimates is unknown, as error can arise from sources of variation such as measurement error, environmental variation, or genetic variation. Ecological models are an abstract, mathematical representation of an ecological system that can make predictions about the dynamics of the real system. To quantify the variation associated with the pre-appearance interval (PAI), we developed an ecological model that simulates the colonization of vertebrate remains by Cochliomyia macellaria (Fabricius) (Diptera: Calliphoridae), a primary colonizer in the southern United States. The model is based on a development data set derived from a local population and represents the uncertainty in local temperature variability to address PMI estimates at local sites. After a PMI estimate is calculated for each individual, the model calculates the maximum, minimum, and mean PMI, as well as the range and standard deviation for stadia collected. The model framework presented here is one manner by which errors in PMI estimates can be addressed in court when no empirical data are available for the parameter of interest. We show that PAI is a potential important source of error and that an ecological model is one way to evaluate its impact. Such models can be re-parameterized with any development data set, PAI function, temperature regime, assumption of interest, etc., to estimate PMI and quantify uncertainty that arises from specific prediction systems.

Simulation of climate-tick-host-landscape interactions: Effects of shifts in the seasonality of host population fluctuations on tick densities.

Tick vector systems are comprised of complex climate-tick-host-landscape interactions that are difficult to identify and estimate from empirical observations alone. We developed a spatially-explicit, individual-based model, parameterized to represent ecological conditions typical of the south-central United States, to examine effects of shifts in the seasonal occurrence of fluctuations of host densities on tick densities. Simulated shifts in the seasonal occurrence of periods of high and low host densities affected both the magnitude of unfed tick densities and the seasonality of tick development. When shifting the seasonal densities of all size classes of hosts (small, medium, and large) synchronously, densities of nymphs were affected more by smaller shifts away from the baseline host seasonality than were densities of larval and adult life stages. When shifting the seasonal densities of only a single size-class of hosts while holding other size classes at their baseline levels, densities of larval, nymph, and adult life stages responded differently. Shifting seasonal densities of any single host-class earlier resulted in a greater increase in adult tick density than when seasonal densities of all host classes were shifted earlier simultaneously. The mean densities of tick life stages associated with shifts in host densities resulted from system-level interactions of host availability with tick phenology. For example, shifting the seasonality of all hosts ten weeks earlier resulted in an approximately 30% increase in the relative degree of temporal co-occurrence of actively host-seeking ticks and hosts compared to baseline, whereas shifting the seasonality of all hosts ten weeks later resulted in an approximately 70% decrease compared to baseline. Differences among scenarios in the overall presence of active host-seeking ticks in the system were due primarily to the degree of co-occurrence of periods of high densities of unfed ticks and periods of high densities of hosts.

Adult nasal glioma presenting with visual loss.

OBJECTIVES: We report a rare case of a nasal glioma found incidentally in an adult, presenting with visual loss, optic nerve oedema and proptosis. CASE REPORT: A 41-year-old woman presented with bilateral proptosis, impairment in visual acuity (6/60 bilaterally) and loss of colour vision. Computed tomography and magnetic resonance imaging showed proptosis, bilateral optic nerve swelling and a heterogeneous mass occupying the left nasal cavity and extending through a skull base defect into the anterior cranial fossa. Biopsy confirmed a nasal glioma. Treatment with intravenous dexamethasone resolved the proptosis, and the patient's visual acuity recovered to 6/9 bilaterally. At the multidisciplinary team meeting, it was felt that the nasal glioma probably represented an incidental finding and was not directly responsible for the patient's proptosis and transient visual loss. CONCLUSION: To our knowledge, this is the first report in the English language literature of adult nasal glioma presenting with visual loss. The management of nasal gliomas in adults is contentious and the relevant literature is reviewed. This case was managed conservatively with regular follow up.

Inflammatory myofibroblastic tumour of the tonsil: case report and literature review.

OBJECTIVE: We present the first reported case in the English language literature of an inflammatory myofibroblastic tumour of the right tonsil in a young, pregnant woman, and we report a management strategy for this enigmatic entity. CASE REPORT: A 28-year-old, pregnant woman presented with a 10-day history of odynophagia despite a course of antibiotics. Examination revealed a grade II, erythematous right tonsil with ulceration on the upper pole. A biopsy was arranged, and initial evaluation was suggestive of spindle cell carcinoma. However, this diagnosis was reviewed after immunohistochemical staining confirmed an inflammatory myofibroblastic tumour. Subsequent complete excision was undertaken using CO2 laser. CONCLUSION: Clinically, inflammatory myofibroblastic tumour of the tonsil is known to be locally aggressive and can present in a manner not dissimilar to a high grade carcinoma of the tonsil. As a result, the recommended treatment is complete local excision with careful follow up.

Benign schwannoma of the tonsil.

The case of a rare tumour in a rare location is presented, and important aspects of the management of similar clinical scenarios are highlighted. Tonsillar schwannoma is a slow growing lesion presenting in the third to fifth decade of life. Histological diagnosis is made through the identification of Antoni A (Verocay bodies) and Antoni B cells with S-100 expression. A 24-year-old man presented with a 5 cm right tonsillar tumour causing dysphagia and dysphonia for 6 weeks. Tonsillar schwannoma can be diagnosed in the outpatient clinic. CT imaging and tissue biopsy are the appropriate investigations followed by complete surgical enucleation. Schwannoma has the potential for malignant transformation, with no recorded cases of this occurring in the tonsil.

An anatomical comparison of Blair and facelift incisions for parotid surgery.

BACKGROUND: The rhytidectomy approach for parotidectomy allows the incision to be hidden, and post-operative scarring minimised. Furthermore, separate elevation of the Superficial Musculo-Aponeurotic System (SMAS) reduces the incidence of Frey's syndrome, and provides vascularized soft tissue for contour reconstruction. The technique has gained popularity particularly with plastic surgeons, but concerns persist that with this approach, particularly with lesions located anteriorly, access to the gland may be inadequate, and facial nerve identification may be compromised. MATERIALS AND METHODS: We undertook an anatomical study to quantitatively compare the surgical access achieved using the facelift approach with the conventional Blair incision, by comparing the distances between the parotid edge and the retracted flaps. RESULTS: Despite reduced tissue elasticity due to formaldehyde fixation, it proved possible to demonstrate all regions of the parotid gland to the operating surgeon with either approach. There were no significant differences in the distance between the parotid edge and the retracted skin flaps (P > 0.1; paired t-test). CONCLUSIONS: The facelift approach provides at least equal access to all regions of the parotid gland when compared to a Blair's incision. It is a superior approach aesthetically and its more widespread use in parotid surgery is advocated.

Influence of acaricide resistance on cattle-fever tick (Boophilus spp.) infestations in semi-arid thornshrublands: a simulation approach.

Cattle-fever tick (Boophilus microplus and B. annulatus) populations that develop acaricide resistance become more difficult to control or eradicate. We used a simulation model to assess the direct and indirect effects of interactions among season, habitat type, grazing strategy, and acaricide resistance on the ability to eradicate Boophilus infestations in semi-arid thornshrublands of Texas, USA. Season of infestation appeared to have the strongest effect, with infestations begun on 27 September (autumn) tending to die out sooner than those begun on 1 March (spring) and to remain undetected. Habitat type had the next strongest effect, with infestations surviving much longer as canopy cover increased from uncanopied buffelgrass (Cenchrus ciliaris) habitats to mesquite (Prosopis glandulosa)-canopied grass habitats. Acaricide resistance had a moderate effect; as expected, highly resistant tick populations survived longer than those with no acaricide resistance. The importance of grazing strategy varied with changes in habitat type: as canopy cover increased, infestation duration increased faster under continuous grazing than under rotational grazing strategies. Importance of grazing strategy also varied with acaricide resistance: detected tick populations with no and slight acaricide resistance subjected to acaricide treatments tended to survive longer under rotational grazing than continuous grazing, due to reduced contact with a treated host. Populations with moderate and high resistance behaved more like untreated populations, tending to survive longer under continuous, rather than rotational, grazing, because they experienced less mortality on a treated host. Assuming acaricide treatments at 2-week intervals and maintenance of cattle in infested pastures, results indicate that, for each habitat type, infesting ticks have a threshold of acaricide resistance below which one can eradicate them faster with continuous grazing than with rotational grazing. As canopy cover increases, this threshold appears to shift from high resistance (in grass) to slight resistance (in mesquite).

Simulation of rotational grazing to evaluate integrated pest management strategies for Boophilus microplus (Acari: ixodidae) in Venezuela.

Ranchers in Venezuela historically have controlled the cattle-fever tick, Boophilus microplus (Canestrini), with acaricide treatments of cattle but no technical planning. We developed a simulation model to evaluate cattle-tick population dynamics in systematic pasture rotation systems and Integrated Pest Management (IPM) approaches to managing ticks in the tropical dry-forest ecological zone of Venezuela. Model output showed five generations of cattle-ticks produced each year throughout the dry and rainy seasons that occur in this zone. Sensitivity analyses showed disproportionately large changes in on-host B. microplus populations in response to small changes in larval mortality rates, such as those resulting from differences in the innate resistance of cattle to tick parasitism. Simulation results with 1-6 pasture systems suggest that adjusting the graze:rest sequence with systematic rotation among 4-6 pastures could suppress, but not eradicate, tick populations.

KTP laser assisted excision of glomus tympanicum.

A 39-year-old female with a two-year history of mild hearing loss and discomfort on air flight descent was found to have a pulsatile mass behind an intact tympanic membrane. A suspected diagnosis of glomus tympanicum was confirmed by computed tomography (CT) scan imaging. The lesion filled the mesotympanum and hypotympanum but the jugular bony plate was intact, confirming the tympanic site of the lesion. This very vascular tumour was exposed by a tympanomeatal flap and the KTP laser used to shrink and coagulate the tumour progressively with minimal haemorrhage and blood loss. Complete excision of the lesion was achieved without the need for bony removal, and with minimal blood loss. The use of the KTP laser to coagulate this vascular lesion allowed safe removal of the tumour and avoided the need for extended facial recess or hypotympanotomy surgery.

Photodynamic therapy: an effective, but non-selective treatment for superficial cancers of the oral cavity.

It has often been claimed that photodynamic therapy (PDT) produces selective destruction of small cancers without affecting the adjacent normal tissue. The objective of our work was to treat small cancers of the oral cavity with PDT and subsequently excise the treated areas for histological studies of tumour and adjacent normal tissue exposed to the same light dose. Eleven patients with histologically proven T1NO oral squamous-cell carcinomas were treated with PDT, using Photofrin as a sensitiser. The tumours plus a surrounding cuff of normal tissue were exposed to 50 J/cm2 non-thermal laser light at 630 nm delivered by surface illumination and the treated areas subsequently excised. Histological staining and image analysis were used to determine the nature and extent of injury. No macroscopic distinction was evident between tumour and normal tissue exposed to light. Histologically, replacement of superficial epithelium, tumour and connective tissue with a fibrinous necrotic slough was seen. There was also loss of endothelium from small vessels, with haemorrhage and thrombosis. Preservation of subepithelial collagen and elastin was demonstrated with EVG staining. No evidence of selective tumour necrosis was found. Although depth of injury was variable, full thickness mucosal necrosis occurred in all cases.

Oculopharyngeal myopathy with sensorineural hearing loss.

A case is reported of a 59-year-old Caucasian male with oculopharyngeal myopathy and sensorineural hearing loss. He presented with progressive ptosis, sensorineural hearing loss over several years and symptoms of mild dysphagia. Further enquiry into his family history revealed that every male member in his family that lived beyond the age of 60 exhibited identical symptoms. Symptoms of ptosis and dysphagia are consistent with the rare autosomal dominant condition of oculopharyngeal myopathy, believed to be due to mitochondrial disease. The combination of ptosis, dysphagia and sensorineural hearing loss with normal distant muscle group biopsy has not been described before.

Retropharyngeal abscess-an unusual complication of anorexia nervosa.

An unusual case of an adult female with anorexia nervosa, who developed a retropharyngeal abscess, is presented. This case is reported both because of the paucity of reports on retropharyngeal abscess and because of the dramatic unusual aetiology.

The effect of photodynamic therapy on the mechanical integrity of normal rabbit carotid arteries.

Photodynamic therapy (PDT) for tumor ablation is effective in the treatment of superficial cancers. Adjunctive intraoperative PDT has been proposed for the "sterilization" of tumor beds after the resection of malignancies. Arteries in photosensitized animal models exposed to appropriate light receive characteristic injury. This study was conducted to determine whether photodynamic injury to the rabbit carotid artery results in thrombotic occlusion or weakening of the vessel wall. PDT of the carotid arteries of New Zealand white rabbits, using either disulphonated aluminum phthalocyanine or 5-aminolevulinic-acid-induced protoporphyrin IX as the photosensitizer, was performed with a light dose of 100 J/cm2. Histologic examination of the carotids treated with either agent demonstrated typical full-thickness loss of cellularity 3 days after PDT. All vessels remained patent, and no inflammatory infiltrate was evident. Elastin van Gieson staining showed preservation of inner and medial elastic laminae and medial and adventitial collagen. Additional rabbits were similarly treated with PDT to 1-cm segments of both common carotid arteries. The animals were sacrificed at 3, 7, and 21 days. The carotids were exposed, and both control and treated segments were subjected to intraluminal hydrostatic distention until the vessels burst. No reduction in the pressure required to burst the vessels was evident in the treated vessels as compared with the control vessels. The authors of the study concluded that despite full-thickness cell death, PDT-treated arteries are not at risk for thrombotic occlusion or hemorrhage.

The role of forensic anthropology in the recovery and analysis of Branch Davidian Compound victims: techniques of analysis.

The recovery and analysis of human remains from the Branch Davidian Compound, Mount Carmel, Texas, was a multidisciplinary team effort. This presentation deals with one aspect of the forensic anthropological contribution to this collaborative endeavor--the examination and inventory of human skeletal remains and the interpretation of these osteological data. Briefly described first are the content and format of the skeletal inventory and the examination procedures used for data collection. Two subsequent sections illustrate the use of these data to determine (a) age, sex, ancestry, stature, and other distinguishing characteristics, and (b) the presence and nature of any premortem, perimortem, and postmortem trauma. The next section shows how these findings assist in establishing positive identification through, for example, comparison with medical, dental, and other background records, especially comparison of premortem and postmortem radiographs of bones or dentition. In this context, we consider also the sorting of commingled remains, which includes preliminary assessment of rapidly decomposing remains prior to autopsy to preserve information crucial to identification.

Bleeding after tonsillectomy in severe von Willebrand's disease.

A case is reported of a HIV-positive patient with severe von Willebrand's disease describing the bleeding complications during and after tonsillectomy. This patient underwent surgery for asymmetrical tonsillar hypertrophy. The tonsils were spontaneously haemorrhaging and there therefore was a suspicion of neoplasia. Despite close cooperation between the ENT Department and the Haemophilia Centre, involving per-operative Factor VIII monitoring and replacement, the patient suffered both protracted primary and secondary haemorrhages. We report this as a cautionary tale as our previous experience with mild to moderate haemophilia has been uncomplicated, but on this occasion there was massive haemorrhage. We feel that tonsillectomy should not be undertaken in a patient with a severe bleeding disorder without an absolute indicate.

Photodynamic therapy of normal rat arteries after photosensitisation using disulphonated aluminium phthalocyanine and 5-aminolaevulinic acid.

Photodynamic therapy of cancer exposes adjacent arteries to the risk of injury and the possibility of haemorrhage and thrombosis. The nature of photodynamic injury to normal arteries has not been satisfactorily defined, and the ability of arteries to recover with time is unclear. To clarify these issues, we have investigated the effects of PDT on rat femoral arteries, using a second-generation photosensitiser, disulphonated aluminium phthalocyanine, and a new method of photosensitisation, using endogenous synthesis of protoporphyrin IX following systemic administration of 5-aminolaevulinic acid (ALA). Pharmacokinetic studies of sensitiser fluorescence were carried out to determine peak levels of sensitiser. Subsequently photodynamic therapy at times corresponding to maximal fluorescence was performed using two light doses, 100 and 250 J cm-2. The nature of injury sustained and recovery over a 6 month period was investigated. Three days following PDT, all vessels treated showed complete loss of endothelium, with death of all medial smooth muscle cells, leaving an acellular flaccid artery wall. No vascular occlusion, haemorrhage or thrombosis was found. A striking feature was the lack of inflammatory response in the vessel wall at any time studied. Re-endothelialisation occurred in all vessels by 2 weeks. The phthalocyanine group showed repopulation of the media with smooth muscle cells to be almost complete by 3 months. However, the ALA group failed to redevelop a muscular wall and remained dilated at 6 months. Luminal cross-sectional area of the ALA-treated group was significantly greater than both control and phthalocyanine groups at 6 months. All vessels remained patent. This study indicates that arteries exposed to PDT are not at risk of catastrophic haemorrhage or occlusion, a finding that is of significance for both the local treatment of tumours and the use of PDT as an intraoperative adjunct to surgery for the ablation of microscopic residual malignant disease.