Endovascular treatment of epistaxis in a patient with tuberculosis and a giant petrous carotid pseudoaneurysm. (73/84)

A 31-year-old man with pulmonary tuberculosis who did not have human immunodeficiency virus had massive epistaxis from a giant petrous internal carotid artery pseudoaneurysm. Endovascular trapping of the aneurysm was performed, curing the epistaxis. MR showed multiple enhancing brain lesions that resolved with additional antituberculous drug therapy.  (+info)

Avid uptake of technetium-99m-HMPAO by an intracranial plasmacytoma during carotid balloon test occlusion. (74/84)

A 56-yr-old woman was evaluated for removal of a tumor at the base of the skull. A test to determine the risk of carotid artery sacrifice was performed prior to surgery using carotid balloon occlusion of the left internal carotid artery and 99mTc-HMPAO perfusion scintigraphy during the occlusion. An unusual intense focus of increased uptake was seen at the site of the primary tumor in the left cavernous sinus. The tumor, found to be plasmacytoma at surgery, demonstrated only mild washout from 30 min to 2 hr after administration of 99mTc-HMPAO, with a tumor-to-cerebellum ratio of 1.6 and 1.5, respectively, and a tumor-to-contralateral cranial ratio of 2.5 and 2.4, respectively. Intracranial plasmacytoma shows good response to radiation therapy, and the differentiation of this tumor from other neoplasms is pertinent to the mode of treatment and surgical approach. Technetium-99m-HMPAO SPECT imaging may be a useful tool in distinguishing these tumors from other neoplasms at the base of the skull.  (+info)

The anatomy of the inferior petrosal sinus, glossopharyngeal nerve, vagus nerve, and accessory nerve in the jugular foramen. (75/84)

PURPOSE: To define the variations of the courses of the cranial nerves and the inferior petrosal sinuses as they enter and traverse the jugular foramen. METHODS: Thirty-nine cadaveric specimens containing the jugular foramen were scanned with 1-mm contiguous axial and coronal CT sections. Each specimen was dissected to evaluate the position of the cranial nerves and inferior petrosal sinus as they entered the jugular foramen. RESULTS: The glossopharyngeal nerve entered the most superior, anterior, and medial aspect of the jugular foramen and descended in the anterior portion of the jugular foramen, often within a groove. The vagus and accessory nerves could not be separated by CT. They entered the jugular foramen most often anterior or anterior and inferior to the jugular spine of the temporal bone and descended in a position ranging from medial to anterior to the jugular vein. The inferior petrosal sinus most often coursed inferior to the horizontal portion of the glossopharyngeal nerve and entered the jugular system in the jugular foramen, at the exocranial opening or below the skull base. A pars nervosa and pars venosa could be identified only at the endocranial opening, where the jugular spine separated the pars nervosa containing the inferior petrosal sinus and three cranial nerves from the pars venosa containing the jugular vein. CONCLUSION: Our evaluation demonstrated anatomic variation in the area of the jugular foramen.  (+info)

Aneurysmal cyst of the petrosal bone. (76/84)

An aneurysmal cyst of the petrosal bone presenting as hearing loss and recurrent bacterial meningitis is reported. None of the clinical or radiographic signs described previously were present. Because other diagnostic methods are not reliable, it is recommended that coronal thin section computed tomography be performed in every case of suspected malformation of the skull base and in the diagnosis of recurrent bacterial meningitis.  (+info)

Impact of a restorative dentistry service on the prescription of apical surgery in a district general hospital. (77/84)

The case records of a group of patients who had undergone periapical surgery in a district general hospital were examined and compared with the criteria agreed by a group of hospital restorative dentists as to whether apical surgery was appropriate rather than, at least initially, a non-surgical treatment option. Only 65% of the patients met the audit criteria. As a result, changes have been made to clinical practice, including a greater involvement of restorative clinicians in the decision-making process when apical surgery is under consideration.  (+info)

Developmental patterns and characteristic symptoms of petroclival meningiomas. (78/84)

Thirty-six cases of petroclival meningiomas with clearly defined anatomical features were selected to analyze the site of tumor attachment and the displacement of the trigeminal nerve. The tumors were classified into four categories according to the origin and extension of the tumor: clival origin medial to the trigeminal nerve (upper clivus type), clival origin with dumbbell extension to the cavernous sinus (cavernous sinus type), tentorial origin over the trigeminal nerve (tentorium type), and petrous apex origin lateral to the trigeminal nerve (petrous apex type). Patients with tumors in each category had characteristic neurological symptoms. Patients with the upper clivus type had oculomotor nerve paresis as a single symptom, if suprasellar tumor extension was present. Patients with the cavernous sinus type commonly presented with abducens nerve paresis caused by epidural tumor invasion around Dorello's canal. Dumbbell tumor extension along the venous drainage of the cavernous sinus was a significant problem for surgical removal in this type. Half of the patients with the tentorium type had a characteristic symptom of trigeminal neuralgia caused by retrograde tumor invasion into Meckel's cave from its orifice, but the cavernous sinus was not involved. The main complaint of patients with the petrous apex type was hearing disturbance, but no epidural or parasellar extension was present. Clinical symptoms and magnetic resonance imaging provide important information about the origin and extension patterns of these tumors, especially the presence or absence of tumor extension into the cavernous sinus. Abducens nerve paresis or trigeminal neuralgia suggests tumor invasion into the cavernous sinus or Meckel's cave, respectively.  (+info)

Imaging findings of the developing temporal bone in fetal specimens. (79/84)

PURPOSE: To trace the development of the normal fetal temporal bone by means of plain radiography, MR, and CT. METHODS: Eighteen formalin-fixed fetal specimens, 13.5 to 24.4 weeks' gestational age, were examined with a mammographic plain film technique, CT, and MR imaging at 1.5 T. Temporal bone development and ossification were assessed. RESULTS: The membranous labyrinth grows with amazing rapidity and attains adult size by the middle of the gestation period. The cochlea, vestibule, and semicircular canals are very prominent and easily recognized on MR images. The otic capsule develops from a cartilage model. Ossification of the otic capsule proceeds rapidly between 18 and 24 weeks from multiple ossification centers that replace the cartilaginous framework. The mastoid, internal auditory canal, vestibular aqueduct, and external auditory canal continue to grow after birth. CONCLUSION: The study of fetal developmental anatomy may lead to a better understanding of congenital disorders of the ear. Faster MR scanning techniques may provide a method for in utero evaluation of the fetal temporal bone.  (+info)

Cholesterol granuloma of the petrous apex: establishment of a drainage route into the superior tympanic cavity--technical note. (80/84)

A 40-year-old male presented with a cholesterol granuloma of the petrous apex manifesting as progressive hearing loss and tinnitus. The lesion was treated via an extradural middle cranial fossa approach employing a new procedure to establish a drainage pathway into the superior tympanic cavity which preserved his hearing. The pathway was formed by a groove 5 mm wide and deep in the anterolateral aspect of the petrous bone, crossing the major petrosal nerve and carotid artery, running around the cochlea, crossing the tensor tympanic muscle, and entering the superior tympanic cavity above the orifice of the eustachian tube. This procedure is easy to perform without special techniques.  (+info)