Inverting papilloma

Findings

Multiple axial T1 images without and with intravenous gadolinium through the nasal cavity reveal a lobulated mass occupying the nasal passages (Figure 1, Figure 2 and Figure 3) with extension into the anterior cranial fossa (Figure 4 and Figure 5) as well as the right maxillary sinus (Figure 3).
This lesion demonstrates heterogeneous enhancement (Figure 2, Figure 3 and Figure 4) on post contrast axial and coronal T1 sequences. There is also thinning and remodeling of the bony septa of the nasal cavity on both axial CT (Figure 6 and Figure 7) and coronal CT reconstructions (Figure 8).

Differential diagnosis
- Esthesioneuroblastoma
- Antral choanal polyp
- Mucocele
- Allergic fungal sinusitis
- Squamous cell carcinoma
- Adenocarcinoma
- Juvenile nasoangiofibroma


Diagnosis: Inverting papilloma


Benign but bulky tumor that usually originates from the lateral nasal wall in the nasal cavity as well as the ethmoidal and maxillary sinuses
"Inverting" term comes from endophytic growth of epithelia into the surrounding stroma
Can often harbor a concurrent squamous cell carcinoma, which enhances more homogeneously and centrally

Inverting papilloma is a benign, slow-growing tumor of epithelial origin that occurs most commonly within the nasal cavity and paranasal sinuses. The term ‘inverting’ stems from the observation on pathology that proliferation of epithelial cells occurs into the surrounding stroma by endophytic growth rather than exophytic growth, as is expected.

Clinically, the typical patient is a male between the ages of 40-60 years. The most frequent complaints are unilateral nasal obstruction, stuffiness, epistaxis, dysosmia, rhinorrhea and pain. Inverting papilloma can affect the orbits by proptosis or by deformation of the bony orbits.

Radiologically, inverting papilloma is a homogeneous and lobulated lesion with scattered calcification in a variety of patterns. On CT, it can often have a lobulated (‘cerebriform’) appearance which has been reported to be very specific. It enhances heterogeneously and peripherally in contrast to squamous cell carcinoma, which enhances more homogeneously and centrally. Inverting papilloma most often arises from the lateral nasal wall, adjacent to the middle turbinate and posterior to the uncinate process. If it affects the paranasal sinuses, it most commonly involves the ethmoidal and maxillary sinuses. Enlargement of inverting papilloma can produce local bone thinning, bowing or erosion. It often grows through the nasal choana into the nasopharynx.

Concurrent squamous cell carcinoma has been reported in about a quarter of cases. This is seen as bony destruction, multicentric soft tissue extension and nodal metastases. CT and MR are complementary in assessing the extent of this tumor’s involvement as this is crucial to planning accurate and complete surgical resection. Treatment involves endoscopic surgical resection but recurrence is rather common.

Brain death from meningitis secondary to ear infection

Findings

Initital head / temporal CT: Pneumocephalus along the left falx of unknown etiology. No evidence of intracranial lesion, midline shift, or intracranial hemorrhage. No fracture of the temporal bones. Widening of the left lambdoid suture with well corticated borders, inconsistent with fracture. Fluid is present in the mastoid air cells bilaterally.

Follow-up CT: Unchanged pneumocephalus. Loss of the suprasellar and quadrigeminal plate cisterns consistent with herniation. Decreasing differentiation between the gray and white matter consistent with edema. Fluid again was seen in the mastoid air cells bilaterally.

Nuclear medicine study: No evidence of flow/perfusion to brain either on the early dynamic images or on the delayed images.

Differential diagnosis:
- Skull fracture
- Meningitis

Epilogue: Patient's girlfriend reported he was diagnosed with an ear infection, but did not fill the prescription. After toxicology consult, possiblity of meningitis was raised. While still in ER the second head CT was done which showed changes of diffuse brain hypoxia with cerebral edema and herniation. Examination at this point revealed fixed and dilated pupils with no brainstem reflexes. ICP monitor was placed showing pressure was significantly elevated, unable to be controlled with hyperosmolar therapy. A nuclear medicine scan was obtained and showed no evidence of flow or perfusion to the brain, findings consistent with brain death when taken in correlation with clinical findings.


Diagnosis: Brain death from meningitis secondary to ear infection


Key points

Differential diagnosis of Pneumocephalus
- Traumatic 74%
May be found within any compartment from skull, skull base, paranasal sinus, or mastoid fracture
3% of all skull fractures
8% of all paranasal sinus fractures
- Neoplasm involving sinus 13%
Osteoma, pituitary adenoma, mucocele, epidermoid, paranasal sinus malignancy
- Iatrogenic 4%
Lumbar puncture, craniotomy, craniectomy, ventriculostomy, ICP monitor placement
- Infectious 9%
Rare sequela of gas-producing infection
Typically sinusitis or mastoiditis
- Regardless, pneumocephalus itself is not a problem—what's causing it?

Epidural
- Remains localized
- Air will not necessarily move with changes in head position

Subdural
- Air-fluid levels
- Moves with changes in head position
- Confluent
- Tension pneumocephalus may result in "Mount Fuji sign"—subdural air separates/compresses frontal lobes, creating widened interhemispheric space between frontal lobe tips—mimics silhouette of Mt Fuji.

Subarachnoid
- Multifocal
- Non-confluent

CT: Imaging tool of choice
MRI: Foci of absent signal on all sequences

Happy Chinese New Year 2009!

The Year 2009 is marked as the Year of the Ox in the Chinese Lunar Calendar. The years 1913, 1925, 1937, 1949, 1961, 1973, 1985, 1997, (and so on with twelve-year intervals), are Ox years.

According to Chinese astrology, people born under this sign are patient, honest, artistic, sincere, and easy to be friends with. Some of the negative aspects, however, are being petty, dogmatic, gullible, critical and intolerant. Ox people are generally compatible with people born under the signs of Snake, Rooster, and Rat. They are incompatible with the Goat people.

The Philippines will experience a slight prosperity in economy. This will also be a crucial year if the Philippines is to become a major contributor in South East Asian economy. The outlook is generally good for those who will start a business.

Okay, okay, I am not geomancer nor an astrologer. The above has only been told to me by a Chinese Feng Shui master whom I consulted yesterday, Chinese New Year's Eve, in Chinatown, Manila. The Chinese are strict believers of this zodiac, and are very meticulous following the Feng Shui so they can have a prosperous business the whole year round. Are they nuts? Look at them now! Giants in businesses and industries. I think I'd better practice the Feng Shui soon.

I will post a few articles and pictures about the Chinese New Year 2009 in the following days. Meantime, let me just greet you for now a Happy Chinese New Year!

Kung Hei Fat Choi!

Rheumatoid arthritis with vertical subluxation and an associated anterior atlantoaxial subluxation at C1-C2

Findings

Figure 1: Axial CT image of the brain displayed in bone windows at the level of the posterior fossa. The dens is subluxed superiorly into the foramen magnum.
Figure 2: Lateral radiograph of the cervical spine in the neutral position. The superior half of the odontoid process is difficult to visualize secondary to overlapping osseous structures. The position of the anterior arch of the atlas in relation to the dens is also not clearly demonstrated. Chronic degenerative changes are incidentally noted at C3-C4.
Figure 3 and Figure 4: T1-weighted and T2-weighted sagittal MR images of the cervical spine. The dens is seen to extend superiorly, occupying a position within the foramen magnum. The anterior arch of the atlas has an abnormal position in relation to the odontoid process, maintaining a position equivalent to the plain film finding of Clark station II. The posterior aspect of the anterior atlas also has a position more than 2.5 mm from the anterior border of the dens.


Diagnosis: Rheumatoid arthritis with vertical subluxation and an associated anterior atlantoaxial subluxation at C1-C2


Vertical subluxation is a malalignment disorder of the cervical spine affecting the C1-C2 junction in patients with rheumatoid arthritis. The definition of vertical subluxation is synonymous with other frequently used terms such as atlantoaxial impaction, vertical atlantoaxial subluxation, odontoid upward migration, cranial settling, and basilar invagination of the odontoid process. Vertical subluxation has been reported in 5 to 22% of patients with rheumatoid arthritis. The inflammatory arthropathy of rheumatoid arthritis alters the synovial structures of the cervical spine and predisposes patients to anterior, vertical, lateral and/or posterior atlantoaxial subluxation. Although anterior subluxation is the most frequent to occur, vertical subluxation is considered to have the highest potential for associated neurological complications.

Rheumatoid arthritis causes progressive erosive changes of the osseous and articular structures at C1-C2, which may subsequently lead to collapse of the facet joints. This process of vertical subluxation stems from extension of the superior aspect of the odontoid process into the foramen magnum. Potentially devastating neurological complications or sudden death can occur as the result of compression of the adjacent brainstem, spinal cord, cranial nerve roots, spinal and/or vertebral arteries. Vertical subluxation may also appear in association with anterior subluxation, which results from the disruption of the transverse atlantoaxial ligament by pannus formation.

Initial evaluation can be performed with plain radiographs. Not all patients with inflammatory arthropathy of the cervical spine are symptomatic, demonstrating the need for a high index of clinical suspicion in patients with chronic rheumatoid arthritis. A lateral radiograph of the cervical spine in a neutral position can be evaluated for vertical subluxation. A multitude of techniques, with varying degrees of sensitivity and specificity, exist for the radiographic analysis of vertical subluxation on plain film. A common methodology includes the use of a MacGregor’s line, which extends from the posterior hard palate to the occiput. An 8 mm extension of the dens above the MacGregor’s line in men and 9.7 mm in women has been described as proof of vertical subluxation. Clark station is another simple method, with the odontoid process divided into three equal parts in length within the sagittal plane. The most superior section is station I, the middle section is station II, and the most inferior section is station III. If the anterior arch of the atlas lies anterior to station II or III of the dens, then vertical subluxation is present. A potential pitfall of radiographic analysis is nonvisualization of the dens, which may occur as a result of overlapping osseous structures, osteopenia or extensive erosion of the dens by rheumatoid arthritis. In addition to the evaluation for vertical subluxation on the lateral film, the distance between the anterior arch of the atlas and the dens must be measured. A distance of greater than 2.5 mm in adults indicates an associated anterior subluxation.

Cross-sectional imaging can be utilized in difficult cases or symptomatic patients with equivocal plain films to establish a diagnosis. The multiplanar capabilities of computed tomography (CT) and magnetic resonance (MR) imaging can better define the anatomic relationships among the occiput, axis and atlas than plain film radiographs. Any destructive osseous changes related to rheumatoid arthritis are also best demonstrated by CT. When neurological compromise is suspected, the modality of choice for brain or spinal cord injury is MR.

Intrabiliary rupture of hydatid cyst-MRCP

Hydatid cysts of the liver exert pressure on the surrounding parenchyma, and in approximately one-fourth of the cases, due to higher pressure in the cyst, the cysts eventually leak into small bile ducts or perforate into large ones. Thus the most common complication of hydatid cyst of the liver is spontaneous rupture into the biliary tract. Intrabiliary rupture occurs into the right duct in 55–60% of cases, into the left duct in 25–30% and rarely into the confluence or gall bladder.

This is a case of a hydatid cyst of the left lobe with MRCP images which ruptured spontaneously into the left hepatic duct. Thick slab and Thin Slab images are shown, with communication with hydatid cyst and left hepatic duct and intraluminal linear filling defects.

Teleradiology Providers

Night of the Quiapo Fiesta 2009

Of course my coverage for the Feast day of the Senyor Nazareno would not have been complete without the night pictures. All my shots here are candid, but some of the people who saw me pointing my camera at them had the time to pose for a smile or a funny face. I believe that it is a wonderful and friendly characteristic of the Filipinos.

Ma Mon Luk restaurant in Quezon Boulevard experienced
a wave of invasion by Nazarene devotees

Eating in the Carinderia after the exhausting procession

Litter everywhere. This will be the taken cared of by the city sweepers in the morning.

Baluuut!!! Sa malamig!!!

Street dancing in Plaza Miranda

Everybody happy!

My coverage series for the 2009 Feast Day of the Senyor Nazareno thus now ends here. My only wish is to have given you joy and happiness by reading my articles and viewing my photos, inasmuch as I did writing and photographing them. I tell you the truth, it was so much fun doing this, that I almost forgot I also have some official work to do. Hahaha! Thank you very much for your support!

P.S. I would like to recommend my friend Sidney Snoeck's blog for an outstanding coverage of the Feast Day of the Senyor Nazareno. I'm sure many among you have already visited Sidney's blog, but for those who haven't yet, please do so here

Parotid gland sialolithiasis

Findings

Parotid duct stone, dilated duct, and associated L parotid enlargement with some mild inflammatory changes.


Diagnosis: Parotid gland sialolithiasis


Key points

Sialolithiasis

80-92% sublingual; 6-20 % parotid; 1-2% minor salivary glands.
1% incidence in autopsy studies; much less commonly symptomatic.
Males > Females; Usually 30-60 y/o.
75% single stones; 5% bilateral.
Sxs: Swelling, discomfort surrounding affected gland. May wax and wane.


Sialadenitis

Enlarged, inflamed gland; May have systemic symptoms.
More elderly, dehydrated, debilitated patients.
May be secondary to obstructing stone, bacterial (MC S. aureus), viral, post XRT.

Important complications:
- Secondarily infected as a result of ductal obstruction/stasis (especially in elderly patients).
- Erosion of calculus through duct wall with chronic fibrotic reaction.
- Poorly functioning gland secondary to chronic inflammation.