A 30-year-old man with prior diagnoses of Bell’s palsy and migraine complications introduced with fourth months of worsening facial weak point accompanied by proper ear ache, swelling, and drainage. Just lately an outdoor facility prescribed him a 10-day course of antibiotics and corticosteroids with no important enchancment in signs. Examination revealed proper auricular proptosis, erythema, and edema of the postauricular pores and skin, and an open purulent wound inferior to the auricle. Examination of the exterior ear canal confirmed edema and important purulent otorrhea. The affected person had been instructed he wanted ear surgical procedure 4 years prior, however he by no means wished it as a result of he was apprehensive about getting facial paralysis. Figure 1 reveals his temporal bone computed tomography (CT) scan.
DIAGNOSIS: INFECTED CHOLESTEATOMA WITH OSTEOMYELITIS
The affected person’s presentation is regarding for both a malignant course of or an infectious course of. Malignancies can generally develop rapidly to the purpose the place the vascular provide to the tumor can’t develop as quick because the tumor is rising. This may trigger parts of the tumor to grow to be necrotic (useless). The necrotic tissue can then grow to be secondarily contaminated and trigger important edema. Malignancies may also contain the facial nerve slowly and trigger facial paralysis. In truth, a sluggish onset facial paralysis wants work as much as rule out malignancy.
Step one within the analysis of this affected person ought to embrace acquiring CT and MRI imaging. The CT (Fig. 1) confirmed important destruction of the temporal bone and destruction of the bone separating the mind from the mastoid (posterior fossa plate and tegmen; Fig. 2). If a mass is seen, a biopsy might be obtained to additional consider the mass. If drainage is current, a tradition needs to be obtained for therapy of the an infection. The MRI (Figs. 4, 5) confirmed important comfortable tissue irritation. The diploma of bone loss seen on CT additionally made us involved that there could also be osteomyelitis current and a technetium 99 SPECT scan was obtained. The SPECT scan (Fig. 3) confirmed there’s additionally osteomyelitis of the temporal bone current along with the cholesteatoma discovered on MRI (Fig. 6).
Cranium base osteomyelitis (also known as malignant otitis externa) is a severe, probably life-threatening an infection of the exterior ear and cranium base. It mostly impacts immunocompromised people (particularly diabetic sufferers) who can’t forestall an infection from spreading from the ear canal into the temporal bone. After getting into the temporal bone, the an infection can then progress quickly throughout the cranium base, in the end resulting in intracranial problems. This affected person was a bit uncommon in that he was not immunocompromised however he had important bony destruction within the temporal bone and the cholesteatoma had secondarily grow to be contaminated resulting in continual osteomyelitis.
Our affected person exhibited signs of cranium base osteomyelitis, together with extreme ear ache and otorrhea. Nevertheless, these signs have been additionally regarding for potential malignancy, which should be dominated out with biopsy and tradition. Examination of sufferers with cranium base osteomyelitis usually reveals purulent drainage with a swollen and tender exterior auditory canal. Facial nerve paralysis is often skilled by sufferers with cranium base osteomyelitis, cholesteatoma, and malignancies of the temporal bone. On this affected person, the paralysis is probably going as a result of cholesteatoma and overlying osteomyelitis.
On this affected person, temporal bone CT scan confirmed an enhancing lesion involving the suitable temporal bone and bony destruction of the suitable mastoid air cells, exterior auditory canal, and inside ear buildings, suggesting cholesteatoma with secondary cranium base osteomyelitis (Figs. 1, 2). Nuclear imaging with technetium-99 bone scan confirmed elevated uptake of radiotracer within the areas of damaging adjustments recognized on CT (Fig. 3). MRI of the mind and IAC additional confirmed cholesteatoma centered on the suitable temporal bone involving these similar buildings (Figs. 4, 5, 6).
The gold normal within the analysis of cranium base osteomyelitis is a technetium-99 bone scan, which entails injection and visualization of a radiotracer that detects osteoblastic exercise and concentrates in areas of bone reworking. To attain the next stage of accuracy, a technetium-99 SPECT scan might also be carried out to localize the an infection. After beginning aggressive antibiotic therapy and establishing the analysis of cranium base osteomyelitis with a technetium-99 bone scan, a gallium-67 scan (which concentrates in areas of lively irritation) is obtained to permit the doctor to watch the response to therapy, decision of the an infection, and look of recurrent illness. Sadly, clinicians who may be much less conscious of cranium base osteomyelitis might solely receive a gallium-67 scan and not using a technetium-99 bone scan. A gallium-67 scan alone can’t differentiate between the pores and skin and comfortable tissue an infection in easy otitis externa versus the bone an infection of cranium base osteomyelitis. Failure to precisely diagnose the situation can result in overly aggressive therapy of sentimental tissue infections with intravenous antibiotics.
Although not all the time current in sufferers with cranium base osteomyelitis, fever and elevated white blood cell depend have been current in our affected person, suggesting a systemic inflammatory response to the an infection, probably as a result of his regular immune perform. Laboratory assessments usually ordered for sufferers with suspected an infection embrace ESR and CRP, that are markers of irritation and could be helpful in monitoring therapy response. Lengthy-term culture-guided antibiotic remedy is the mainstay of therapy for cranium base osteomyelitis, and its period relies on symptom decision, laboratory assessments, and repeat gallium-67 bone scans. In the end, our affected person was recognized with right-sided cholesteatoma with secondary cranium base osteomyelitis and abscess formation related to Pseudomonas an infection. Within the absence of diabetes or an different immunosuppressing situation, it’s uncommon that this affected person developed cranium base osteomyelitis. Nevertheless, his pre-existing cholesteatoma might have served as a nidus for an infection and a route for an infection to enter the temporal bone.
Cholesteatomas can invade and erode the buildings of the center ear (the ossicular chain), the inside ear, and the encompassing bone of the cranium (mastoid cavity, tegmen, and petrous apex). This affected person was first handled with long-term IV antibiotics for cranium base osteomyelitis and to settle the pores and skin and comfortable tissue an infection. Nevertheless, surgical resection to clear all epidermal components from the temporal bone is the definitive therapy of cholesteatoma. As a result of the cholesteatoma eroded the bone of the cochlea, this affected person had important listening to loss, and a translabyrinthine method could be used, throughout which the cochlea might probably be preserved. The plan of preserving the cochlea would permit the affected person to have a cochlear implant sooner or later. Sarcastically, the affected person prevented surgical procedure 4 years prior as a result of a worry of facial paralysis. Nevertheless, cholesteatoma can result in facial paralysis if left unchecked. In skilled fingers, the probability of facial paralysis from cholesteatoma surgical procedure is far decrease than if it have been left to develop, particularly in a younger affected person.
BONUS ONLINE VIDEOS: VISUAL DIAGNOSIS
Learn this month’s Medical Session case, then watch the accompanying movies from Hamid R. Djalilian, MD, to overview the affected person’s imaging for your self.
- Video 1. Axial (horizontal) CT of the temporal bone displaying important destruction of the inside ear buildings.
- Video 2. Coronal (vertical parallel to face) CT of temporal bone displaying the destruction of the bone separating the mind from the ear (tegmen).
- Video 3. Technetium 99 SPECT (fused axial CT picture with bone scan picture) on the basal flip of the cochlea stage displaying irritation in all the proper temporal bone.
- Video 4. MRI T1 Axial post-contrast MRI displaying irritation in temporal bone and comfortable tissues of the auricle and scalp.
- Video 5. MRI T1 coronal submit gad displaying enhancement of dura.
- Video 6. Coronal HASTE sequence MRI displaying the hyperintense (brilliant) space in proper temporal bone indicating cholesteatoma.
Watch the affected person movies on-line at thehearingjournal.com