External Canal Research Articles

Pinnal squamous cell carcinoma in cats and the effectiveness of treatment with radical pinnectomy

  The aim of this study was to observe the effectiveness of treatment with radical pinnectomy and investigate postoperative relapse cases in pinnal squamous cell carcinoma in cats. Twelve cats which were brought to surgery clinic of Istanbul University, Faculty of Veterinary Medicine were used. Biopsies were taken from the cases in which squamous cell carcinoma was suspected following anamnesis and the clinical examination of patients that were brought to our clinic. The patients were diagnosed on the basis of histopathological analysis of biopsy samples. Haemogram and biochemical blood analysis were performed and thoracic radiographs were taken as routine in cases that a decision was made to operate. After the area was prepared for operation radical pinnectomy or total external acoustic canal ablation along with radical pinnectomy were performed in the patients that were eligible for operation. Relapses seen in the postoperative period were re-operated with the techniques selected according to invasion status. Periodic controls of the patients were made after the operations and the cats were examined for relapse. In seven out of 12 cases, only squamous cell carcinoma; in three cases, actinic dermatitis actinic dermatitis in addition to squamous cell carcinoma, and in two cases, only actinic dermatitis lesions were detected. In the postoperative period, relapse was observed in the cases in which the squamous cell carcinoma lesion reached the lower half of the pinna or the external acoustic canal while relapse was not observed in cases with actinic dermatitis lesions or when the squamous cell carcinoma lesion was on the top part of the pinna. Relapse cases were re-operated using different operative techniques. It is concluded that performing radical pinnectomy on actinic dermatitis lesions detected on the pinna before development into squamous cell carcinoma, and removing the tumour according to its localization with radical pinnectomy or total external acoustic canal ablation alongside radical pinnectomy is the most reliable treatment option in terms of relapse in cases of pinnal squamous cell carcinoma.  

Temperatura de polimerização da resina acrílica odontológica na medula espinhal de ratos Wistar

Objetivou-se investigar se a temperatura de polimerização da resina acrílica odontológica ocasiona sinais neurológicos e alteração histológica na medula espinhal de ratos. Foram utilizados 48 ratos, Wistar, distribuídos em dois grupos denominados GI ou cimento ósseo (controle positivo) e GII ou resina acrílica odontológica. Cada grupo foi redistribuído em seis subgrupos, de acordo com a quantidade do composto, o tempo de pós-operatório e o local de aferição da temperatura. O cimento ósseo ou a resina acrílica odontológica foram moldados e colocados sobre as lâminas ósseas dorsais e os processos espinhosos das vértebras L1 e L2. A temperatura de polimerização do composto foi aferida a cada 10 segundos. A temperatura máxima de polimerização e a diferença entre a temperatura externa e a interna ao canal vertebral foram maiores nos subgrupos que receberam 10 gramas. Não foi observada alteração neurológica em nenhum dos animais deste estudo. Na análise histológica, foi observada reação inflamatória de intensidade variável na meninge e no parênquima medular. Pode-se concluir que a temperatura de polimerização da resina acrílica odontológica nas quantidades de um e 10 gramas provoca alterações histológicas na meninge e no parênquima medular, sem ocasionar sinais neurológicos em ratos.

Occult middle ear and mastoid fluid in acute otitis externa

Presence of fluid in the middle ear (ME) or mastoid air cells in acute otitis externa (OE) has not been reported. We hypothesize that in patients with OE there is often otitis media (occult middle ear and mastoid fluid) and secondary fluid in the mastoid air cell system, which is not seen during a clinical examination because of edema in the external canal skin. Retrospective chart review. We reviewed the medical records of 209 patients who presented to our ear, nose, and throat (ENT) clinic with acute OE that was resolved with oral and/or topical antibiotics. Twenty-seven of the 209 patients presented with unilateral or bilateral acute OE (29 ears) and received a computed tomography (CT) scan of their temporal bones, which was ordered by the Emergency Department or ENT services. Twenty-three of 29 ears (79%) showed fluid in the ME, mastoid, or both. Nine of the 10 patients (82%), who obtained their CT scan within 1 week of symptom onset, were found to have fluid. These findings support our hypothesis and serve to inform the medical community (both ENT and primary care) that fluid is often present in the ME or mastoid in patients with acute OE whose symptoms will resolve with oral and/or topical antibiotics.

Middle and inner ear malformations in mutation‐proven branchio‐oculo‐facial (BOF) syndrome: Case series and review of the literature

Hearing impairment is common in individuals with branchio-oculo-facial (BOF) syndrome. The majority of described individuals have conductive hearing impairment due to malformed ossicles and/or external canal stenosis or atresia, although a sensorineural component to the hearing impairment in BOF syndrome is increasingly being reported. Sophisticated computed tomography (CT) of the temporal bone has revealed middle and inner ear malformations in three previous reports. We present middle and inner ear abnormalities in three additional individuals with mutation-proven BOF syndrome. We suggest that temporal bone CT imaging be included in the medical workup of a child with BOF syndrome, in order to guide management.

Complication of dilute vinegar therapy for external auditory canal cholesteatoma

We read with great interest the recent article by Chang et al. [1] which advocated the use of repeat irrigation with dilute vinegar in conjunction with regular microscopic local cleansing to manage spontaneous external auditory canal (EAC) cholesteatoma. In their series of 16 patients, they declared no complications resulting from this treatment regimen. However, we wish to report that when we trialled the very same regimen on one of our patients, our patient suffered a perforated tympanic membrane with subsequent worsened pain and otorrhoea, just 7 days after starting this treatment. Her external canal cholesteatoma was classified as grade I according to Chang’s suggested temporal bone CT staging, i.e., with flattening of the bony external canal. She had surgical debridement and reconstruction of the EAC 6 months previously and was keen to explore another treatment option apart from repeat surgical intervention. She followed the self-cleansing instructions exactly as described in Chang’s paper, using a 10-ml syringe to gently irrigate her ear canal with dilute vinegar, 40 ml in total volume daily, aiming towards the posterior canal wall. When the tympanic membrane perforation was detected at her next clinic visit, she was instructed to stop the vinegar washouts and to commence a course of quinolone ear drops, after which her otorrhoea improved. She is currently still attending our clinic regularly for repeat microsuctioning of her canal cholesteatoma. If her perforated tympanic membrane fails to heal (and it has not done so thus far after 5 weeks), then performing a tympanoplasty would be the next obvious option.Cadaveric studies have found an association of ear irrigation with rupture of atrophic tympanic membranes with the lowest tensile strength but not of normal tympanic membranes [2]. Our patient’s tympanic membrane was essentially normal before the perforation event and her cholesteatoma is solely confined to the EAC, as confirmed on computed tomography scanning on two separate occasions. We would like to politely enquire if the authors have experienced similar complications since publication of their paper or if they have any further insights into the vinegar regimen to share with us.

Keratinosis: A New Entity in the Tropics?

A patient presented with the symptoms of ear block, itching and whitish exudates from the left ear. There was no history of pain, foul smell, tinnitus, or giddiness. Clinical examination revealed whitish keratin like substance filling the external auditory canal. There was no foul odor like cholesteatoma. There was no pain on pulling the pinna to indicate an acute external otitis. Tuning fork tests revealed a mild conductive hearing loss with Rinne test positive and weber lateralizing to the left ear. After a suction toilet of the ear, the tympanic membrane looked normal with no attic or any perforation of the ear drum. The skin of external ear canal was not inflamed. The canal was not widened. There was an absence of wax. Repeated ear swabs did not grow any organisms. Histopathology was keratin. The remaining parts of the external ear including pinna and tragus were normal with no signs of allergic skin reaction. The other ear and rest of otolaryngological examination was normal. A dermatology consultation did not reveal any other skin pathologies. Hence steroid cream (betamethasone) was applied to the external canal after an ear toilet, with instructions to avoid water getting into the ears. This was repeated on a weekly basis. The external auditory canal was back to normal in 3 weeks time. This patient was followed up for 6 months period up to date on a monthly basis and there has been no recurrence. Normal wax had started to be secreted. This condition has been seen and treated by me in a similar fashion for another 10 patients including children, with similar results. However for children and infants since toileting is difficult and hesitancy to application of a steroid cream, olive oil drops two or three times daily for a period of 3 weeks usually clears up this condition. Since this does not fit in with an external otitis acute/chronic of an infective, seborrheic or allergic type, keratosis obturans or an external ear canal cholesteatoma, I feel it is a hitherto undescribed entity. I have worked in the UK, gulf (Oman), and India and not seen a similar condition elsewhere in my 40 years of otolaryngology practice and hence this report

Carcinoma de células ceruminosas en perro

The ear is divided into three parts: the external ear, middle ear, and internal ear. The external ear is a funnel-shaped structure that channels air vibrations to the tympanic membrane. It consists of the auricle (pinna) and the external ear canal (external acoustic meatus) that extend to the tympanic membrane. The structure of external ear canal is both cartilaginous and osseous. Some hair and many tubular ceruminous and sebaceous glands are present in the canal. Their secretions forms cerumen, a mucilaginous fluid containing brown granules. Two surgical techniques are available for the treatment of neoplasms of the external canal: the lateral resection, for small neoplasm's nodules of the canal; and the ablation of the ear canal, operation of choice when the neoplastic mass is deep and extensive, within the ear canal. It describes the case of a male dog, Cocker Spaniel, ten years old, patient treated in Surgery, Faculty of Veterinary and animal Sciences, University of Chile, with an episode of external otitis and a tumor that involved the right ear pinna and external right ear canal. It was decided proceeded taking samples for biopsy and subsequently to perform the removal of the external ear canal. The histopathologic diagnosis was ceruminous gland cell carcinoma.

Facial Nerve Schwannomas Presenting as Occluding External Auditory Canal Masses

Introduction: Facial nerve schwannomas are rare tumors of the lateral skull base. Treatment options for these tumors include observation, stereotactic radiation, and microsurgical removal. Erosion of the bony posterior canal from the descending segment of an entirely intratemporal tumor is an unusual growth pattern. With tumor in the external canal, a unique set of clinical challenges arises. We discuss the management strategies for facial schwannomas with this unusual growth pattern in patients of two disparate ages.

Removal of Hairy Polyp of the Eustachian Tube Using a Novel Skull Base Approach: Extended Transmastoid Excision

Hairy polyps are rare dermoid tumors associated with the temporal bone. The majority of reported cases have been left-sided, in women, and with significant middle ear or nasopharyngeal components, allowing removal by a simple transmastoid or endoscopic approach. We present the case of a 3-year-old girl with a hairy polyp of the left eustachian tube. Diagnosis was made at surgery 14 months after initial presentation. Preoperative CT and MRI aided surgical planning but were nondiagnostic. The location of this lesion high in the eustachian tube and its intimate association with the carotid artery precluded a traditional transcanal, endoscopic, or simple transmastoid approach and required more aggressive surgical dissection. A novel extended transmastoid skull base approach with removal and replacement of the anterior external canal wall and glenoid fossa provided complete visualization of the intrapetrous portion of the carotid artery, which was immediately adjacent and adherent to the tumor, and granted access to the apex of the cartilaginous eustachian tube from which the tumor arose. This exposure allowed for complete excision of the tumor and reconstruction of the ear with the usual features of a canal wall down mastoidectomy. This case represents the 15th such lesion reported in the English literature and the first described extended transmastoid skull base approach for complete visualization of the intrapetrous portion of the carotid artery and access to the cartilaginous eustachian tube.

OSSICULAR CHAIN PRESERVATION IN EPITYMPANIC CHOLESTEATOMA SURGERY

To the Editor: We read the recent article by Marchioni et al. (1) about ossicular chain preservation using the endoscopic transcanal tympanoplasty approach with great interest. We agree with the authors that when it does not compromise cholesteatoma removal, the entire ossicular chain should be preserved to achieve optimum hearing results. Even the best prosthetic ossicular reconstruction cannot consistently match the hearing possible with an intact, mobile ossicular chain. However, the endoscopic technique for addressing epitympanic cholesteatoma only allows for ossicular chain preservation in 56.5% of cases and was much less successful when the cholesteatoma involved multiple subsites, especially the medial attic and antrum. Additionally, the reported recurrence rate in the middle ear is 13%. We believe the modified Bondy technique is the procedure of choice in cases of uncomplicated, epitympanic cholesteatoma with an intact ossicular chain and pars tensa (2). In our series of 230 consecutive cases (3), we were able to preserve an intact ossicular chain in all cases and were able to eradicate disease in 1 stage, regardless of location in the epitympanum. There was no recurrent disease in the middle ear after a follow-up period exceeding 7 years. Postoperatively, 88% of our patients had preserved or improved hearing by air conduction. This technique allows for bimanual surgery and is not limited by external canal size or bleeding, which makes an endoscopic approach difficult. Of course, cholesteatoma surgery is complex, and no one surgical approach can be applied to all circumstances. No single surgical technique can substitute for sound surgical decision making and mastery of a variety of surgical approaches. We commend the authors for their work in exploring novel ways of addressing a challenging problem. Mario Sanna, M.D. Trac M. Duong, M.D. Gruppo Otologico Piacenza, Italy

An objective comparison of leakage between commonly used earplugs

ObjectiveWe sought to determine the efficacy of commonly used earplugs using an anatomically correct ear model. MethodsThe total volume and rate of water that leaked past the earplug and subsequent defect in the tympanic membrane over separately measured 30, 60, 120, and 180-second intervals were recorded. Scenarios tested included a control with no earplug, custom molded earplug (Precision Laboratories, Orlando, FL), Mack's plug (Warren, MI), Doc's plug (Santa Cruz, CA), and cotton balls coated with petroleum jelly. ResultsAll plugs tested resulted in less leakage at all time points when compared with no plug (P < .05). At 30 seconds, the custom molded, Mack's and Doc's plugs all showed significantly less leakage when compared with the cotton ball coated with petroleum jelly (P < .05). At 60, 120, and 180 seconds, Mack's, Doc's, and the cotton plugs all showed significantly less leakage compared with the customized plug (P < .05). At 120 and 180 seconds, Mack's plugs had significant less leakage than the cotton plug (P < .05). Among the types of plugs, the molded variety (Mack's) showed the least volume and lowest leakage rate (f4,45 = 94 [P < .001]). In addition, Doc's and cotton balls coated with petroleum jelly were more effective than the customized earplugs. ConclusionsIf the clinician feels that middle ear and external canal water exposure should be minimized, then use of earplugs, particularly the moldable variety, merits further consideration.

Non-accidental caustic ear injury: Two cases of profound cochleo-vestibular loss and facial nerve injury

Non-accidental caustic injury is a rare form of child abuse usually secondary to forced ingestion. Caustic injury to the ear most commonly arises from battery lodgement in the external canal. This case series represents the first report of non-accidental caustic injury to previously normal ears resulting in profound sensorineural hearing loss, vertigo with horizontal canal hypofunction and in one patient a severe facial nerve paralysis. Both patients required blind-end sac closure of the injured ear and one required sural nerve interposition combined with transfer of the masseteric branch of the trigeminal nerve to the ipsilateral facial nerve.

An Inexpensive, Reproducible Anatomic Model for Surgical Training of Myringotomy

Objective: Design an inexpensive, reproducible anatomic model to simulate myringotomy and tympanostomy tube placement in the surgical skills laboratory, which would allow residents to familiarize themselves with the microscope, anatomy, and tools used during a typical procedure. Method: Design an inexpensive, reproducible anatomic model to simulate myringotomy and tympanostomy tube placement in the surgical skills laboratory, which would allow residents to familiarize themselves with the microscope, anatomy, and tools used during a typical procedure. Results: The model was assembled by sawing the styrofoam head in half and making medial and lateral openings. The medial portion of the simulator ear was removed and the ear placed within the external opening of the head. A T-pin was molded to represent the malleus and secured at the inner edge of a three cm segment of detached bulb syringe tip. Glad Wrap was draped over the “malleus,” and the entire assembly was then placed within the medial opening of the head to line-up with the external canal. The “tympanic membrane” is the only disposable portion of the model. Conclusion: This model is a practical and reproducible anatomic model for simulation training of a myringotomy. It has been used successfully by multiple residents and can be created by utilizing inexpensive materials. We plan to integrate this into a Verification of Proficiencies (VOP) program to assess surgical skills in otolaryngology residents.

Bilateral Clinical Pathology of the Temporal Bone

Objectives/Hypothesis: The aim of this study is to indicate anatomic and immunologic peculiarities of the temporal bone which leave it vulnerable to traumatic, infectious and neoplastic insult. Study Design: Seven patients' cases are described in which the clinical pathology of the temporal bone was bilateral. The bilaterality of these cases serves to illustrate the anatomic points which are the focus of this study. Methods: This is a case series. Results: The seven paradigmatic cases are described and the relevant anatomy is explored. These are bilateral tuberculosis of the middle ear and mastoid, bilateral histiocytosis X, bilateral external canal amyloidosis, bilateral middle ear polyposis in Samter's triad, bilateral temporal bone fractures, bilateral middle cranial fossa encephaloceles, and bilateral congenital enlarged superior vestibular nerve canals. The thinness of the skull base, the many fluid-filled and tissue-filled canals which enter the temporal bone and the thinness of the tissues investing all the surfaces contribute to the temporal bone's vulnerability to trauma, infection and neoplasm. Conclusion: Cases of bilateral temporal bone pathology demonstrate the temporal bone's structural and immunologic weaknesses.

Dilute vinegar therapy for the management of spontaneous external auditory canal cholesteatoma

The purpose of this study is to evaluate the efficiency of conservative dilute vinegar therapy in the management of spontaneous external auditory canal cholesteatoma (EACC). From 2000 to 2007, 19 patients presented to our clinic with spontaneous EACC. EACC was divided into four grades based on the temporal bone computed tomography: grade I with flattening of bony external canal, grade II with partial destruction of inferior bony canal, grade III with total destruction of inferior bony canal and grade IV with bony destruction into the middle ear and mastoid cavity. Clinical findings and treatment results were recorded. Microscopic local cleansing and dilute vinegar therapy was conducted in the ears with grades I, II and III. Combined mastoid surgery and dilute vinegar therapy was conducted in four ears with stage IV. There were no recurrences after average of 31 months follow-up. Spontaneous EACC can be effectively controlled with dilute vinegar therapy after microscopic local cleansing. However, surgery must be considered in the cases which have involved the mastoid and middle ear. Dilute vinegar therapy in combination with microscopic local cleansing was effective in the management of spontaneous EACC. Dilute vinegar therapy is an easy, cost-effective, and home-based cleansing method to prevent EACC and promotes healing. However, long-term follow-up may reveal frequent recurrence of cholesteatoma debris and involvement of middle ear or mastoid cavity, and then meticulous debridement with skin graft or surgical intervention should be considered.

Spontaneous Posterior Wall External Canal Cholesteatoma

A 44-year-old woman with a history negative for trauma, inflammation, surgery, or radiotherapy of the head or neck was referred for cerumen removal. Following the cerumen removal, a dehiscence of the posterior wall of the bony canal with squamous debris suggestive of external canal cholesteatoma was ob-served (figure).This is a rare condition usually involving the inferior auditory canal.

Anatomic Analysis of the Mastoid Tegmen

To examine the dural slope shapes and slope depths in different axes in the mastoid. These are important for surgical guidance. Setting-Tertiary care otologic center. Patients/materials-105 temporal bone CT scans were used from subjects who had undergone High Resolution Temporal Bone CT scanning for CSOM, using the non-diseased ear scans. In addition, 21 "diseased side" temporal bones were included. Scans were reconstructed in 3D using Amira software to examine tegmen shapes. The highest and lowest points on the tegmen were measured along 4 axes, 2 in the coronal plane (latero-medial axes posteriorly and anteriorly [L-M ant and L-M post]), and 2 in the sagittal plane (posterio-anterior axes medially and laterally [P-A med and P-A lat]). The highest and lowest point difference was labeled ΔH. We also measured the height from the superior external canal to the tegmen. There was a unimodal distribution in the ΔH variable for all axes measured. Means and (SD) in mm for ΔH are as follows: L-M post 4.1 (2), L-M ant 2.9 (2.2), P-A med 6.5 (1.9), P-A lat 5.4 (2.2). Tegmen-EAC lat and med height means were 8.4 and 9.7 mm respectively. Representative 3D shapes are presented. There appears to be a unimodal distribution of mastoid tegmen shapes and sizes, without clustering into subpopulations. The tegmen slopes have real implications for surgical exploration and disease eradication. A Tegmen classification scheme is presented.

Evaluation of Orchidopexy with or without Opening the External Oblique Fascia in Children with Superficial Inguinal Undescended Testis

Orchidopexy is one of the most common pediatric surgeries. In general, the operation for truly undescended testis (UDT) includes opening of the external oblique fascia. The most common location of the testis in UDT is adjacent to the external inguinal canal (superficial inguinal type). Using a new method we performed orchidopexy without opening the fascia. In this clinical trial we compared the outcome after a classic procedure with that obtained using our method. This clinical controlled trial was undertaken in the Al Zahra hospital between 2008 and 2010. Patients were randomized into either into the closed technique group (group A, n=52) or the open group (group B, n=52). The incidence of short-term and long-term complications was recorded with a specific questionnaire at the time of surgery and at follow-up visits. Data were analyzed with the SPSS 15.0 software using chi-square and t-tests. 104 patients were included in this study. The incidence of short-term complications (surgical site hematoma, surgical wound infection, scrotal hematoma) and long-term complications (testicular atrophy) did not differ significantly between the 2 groups. Procedure duration in group A was significantly shorter than in group B (p=0.001). Medial thigh sensory loss was more common in group B (p=0.05). When investigating the surgical management of undescended testes, our study found differences in medial thigh sensory loss rate and procedure duration between the open and closed techniques. Operative treatment of UDT without opening the external oblique fascia is highly recommended.

CT Sialography in the Dog - A Cadaver Study

To document computed tomographic topography of salivary glands and their ducts in dogs, a retrograde filling with methylcellulose and iodinated contrast medium was performed in three cadavers. Demarcation of the parotid, mandibular and zygomatic glands was achieved. Surrounding structures were imaged without beam hardening artefacts. Landmarks for the parotid, mandibular and zygomatic glands were the external acoustic canal, the mandibular angle and the pterygopalatine fossa, respectively. Sialograms of the parotid, mandibular and zygomatic ducts were achieved, whereas neither the sublingual glands nor their ducts could be contrasted. The images provide a three-dimensional visualization of the salivary glands and their ducts.

Strepsiptera

Who or what are Strepsiptera? The Strepsiptera, or ‘twisted-winged parasites’ are an order of parasitic insects. They can be found all over the world, living inside a wide variety of insect hosts. They were discovered in 1793 and are defined as ‘entomophagous endoparasitoids’. Strepsipterans attack insect species from 34 families distributed across seven orders — from silverfish to true flies. Strepsiptera are considered a small insect order with only around 600 described species; although this figure is almost certainly a considerable underestimate. Whom they are most closely related to has been controversial, but recent studies suggest they are more closely related to beetles or their allies (the neuropterids) than to flies or other insects. What is so unusual about them? Being parasitoids, strepsipterans show a number of extraordinary life-style features; for instance, the sexes are dramatically dimorphic. Females almost universally live in the host from infection as first instar larvae, right until the end of their life cycle. Consequently, they have lost eyes, antennae, legs and wings, and instead retain a larva-like appearance during reproductive maturity. The result is a cryptic and morphologically simplified organism (Figure 1). This is counterbalanced by increased size and reproductive output. Males, by contrast, emerge after pupation in the host as small free-flying insects. Their only task in the outside world is to find a female. This must make sex rather cumbersome? True. Mating has to occur with the female inside the living host. The female extrudes a structure, the cephalothorax, through which the male inserts his sperm. Females give birth to live young, which is untypical for most insects, and the progeny reach the outside world via an external brood canal opening in the cephalothorax. The first instar larvae then actively seek out a new host — but how exactly they do this is not known. Is this true for all strepsipterans? No. In contrast to the above, one strepsipteran family (Mengenillidae) displays ‘transitional’ parasitic characteristics, i.e. pupation takes place outside the host, and the female is free-living. What happens to the hosts? Strepsipterans have a very interesting interaction with their hosts. They sit very close to the parasite–parasitoid boundary. While parasitoids (typically wasps) directly kill their hosts, the association between strepsipterans and their hosts lasts longer and is more stable than in other parasitoids. Little experimental work has been conducted on how strepsipterans alter the behaviour of their hosts. Initial studies suggest that paper wasps that have been stylopised — this term is used to describe insects parasitised by Strepsiptera — desert the colony to form aggregates outside of the nest. Stylopisation can also result in morphological alterations: for example, in infected plant and leaf hoppers external genitalia can be extremely reduced, or even lost entirely. Why are strepsipterans so little known? This may be primarily due to the fact that they hardly occur as free-living insects — except for some members of the family Mengenillidae and the brief female-searching expedition of males, which live for only five to six hours as adults. Adult female Strepsiptera are only distinguishable by the presence of the cryptic cephalothorax that protrudes from the cuticle of the host, and juveniles can only be discovered by host dissection. So, why should we care about them? Their unique biology makes them an exciting model system for a wide range of questions. In evolution and ecology, parasites are crucial subjects for research, from their role in food webs and biological control to the underlying causes of speciation and host specificity. The strepsipteran family Myrmecolacidae is of special interest because it is parthenogenetic and includes one of the smallest insect genomes so far recorded. Furthermore, Myrmecolacidae display a very rare strategy: males and females of the same species attack completely different host species (males typically infect ants, whereas females attack grasshoppers, crickets or praying mantids). Male hosts include the invasive red imported fire ant, Solenopsis invicta, a highly problematic pest species that has severe negative consequences for humans and wildlife. The flight and sensory systems of male strepsipterans are also of interest. For example, the anatomical organization of the eye has been proposed as a modern counterpart to the ancient trilobite visual system, and their forewings are functionally ‘analogous’ to the halteres of true flies. In addition to the unusual fan-like shape of the flight-providing hindwings, these structural oddities may offer important comparative insights into sensory evolution and the biomechanics of insect flight. Furthermore, while a number of insect groups demonstrate considerable sexual dimorphism, none are quite like Strepsiptera, the females of which are morphologically extremely simplified. By comparing Strepsiptera with different insect systems, developmental studies could offer important insights into the evolution of development and metamorphosis.