Annotated Bibliography
Nolan Altman, James A. Brunberg, Allen D. Elster, Ajax E. George, David B. Hackney, Robert B. Lufkin, JeffreyS. Ross, Joel D. Swartz , Jane L. Weissman , and Samuel M. Wolpert
Brain Tumors and Cysts
Peterson DL, Sheridan PJ, Brown WE Jr. Animal models for brain tumors: historical perspectives and future directions . J Neurosurg 1994;80:865-876.
An excellent review of animal models available for those involved in brain tumor research. Included are spontaneous tumors, carcinogen-induced tumors, virus-induced tumors, models based on cell or tissue transplantation , and transgenic models. This paper is not for the general reader, but will be of great interest to academicians and researchers.O ADE
Degenerative and Metabolic Disease and Aging
Bensimon G, Lacomblez L, Meininger V, and the ALS/ Riluzole Study Group. A controlled trial of riluzole in amyotrophic lateral sclerosis. N Eng/ J Med 1994;330: 585-591.
One hypothesis about the origin of amyotrophic lateral sclerosis implicates abnormal accumulation of glutamate (the primary excitatory central nervous system neurotransmitter) at synapses. Experimentally, riluzole inhibits the presynaptic release and postsynaptic actions of glutamate. This double-blind, placebo-controlled, prospective study was carefully performed and analyzed. Survival in the riluzole group was statistically greater than survival in the placebo group; the effect was greatest in patients with bulbar-onset amyotrophic lateral sclerosis, with only a "trend" in patients with limb-onset disease. Riluzole also slowed the deterioration of muscle strength. So far, therapy for amyotrophic lateral sclerosis has been inadequate. These results might constitute a breakthrough.OJLW
Lipton SA, Rosenberg PA. Mechanisms of disease: excitatory amino acids as a final common pathway for neurologic disorders. N Eng/ J Med 1994;330:613-620.
This review article clarifies some mechanisms briefly alluded to in the preceding article. Glutamate, the principal excitatory CNS neurotransmitter, is involved in cognition, memory, movement, sensation. Overstimulation of glutamate receptors may cause "excitotoxicity" and cell death in acute injury (stroke, trauma, hypoglycemia, epilepsy) and chronic injury (amyotrophic lateral sclerosis) . The article goes into exquisite technical detail , but it is important and worth skimming.OJLW
Aylward EH, Brandt J, Codori AM, Mangus RS, Barta PE, Harris GJ. Reduced basal ganglia volume associated with the gene for Huntington's disease in asymptomatic atrisk persons. Neurology 1994;44:823-828.
Volumes of the basal ganglia structures were significantly reduced in asymptomatic at-risk siblings of Huntington patients with marker-positive genes, but not in siblings with marker-negative genes.O SMW
SchneiderS, Feifel E, Ott D , Schumacher M, Luking CH, Deuschl G. Prolonged MRI T2 times of the lentiform nucleus in idiopathic spasmodic torticollis. Neurology 1994; 44:846-850.
Magnetic resonance (MR) findings in 22 patients with spasmodic torticollis were compared with those of 28 agematched control subjects. T2 values in the putamen and pallidum on both sides were significantly higher in the patients than in the controls. The authors speculate that the findings could represent focal gliosis.OSMW
Rouanet F, Tison F, Dousset V, Corand V, Orgogozo JM. Clinical/scientific notes: early T2 hypointense signal abnormality preceding clinical manifestations of central pontine myelinolysis. Neurology 1994;44:979-980.
In this interesting case report, the authors describe a patient with central pontine myelinolysis in whom an MR study revealed hypointense signal on T2-weighted sequences in the basis pontis 1 week before the onset of clinical signs of the disease while the patient was still markedly hyponatremic. On a second MR image obtained 1 week later, the typical appearances of central pontine myelinolysis, hypointense areas on T1-weighted and hyperintense on T2-weighted images, were seen.OSMW
Graham SH, Meyerhoff DJ, Nat R, et al. Magnetic resonance spectroscopy of N-acetylaspartate in hypoxicischemic encephalopathy. Ann Neuro/1994;35:490-494.
Water-suppressed proton MR spectroscopic imaging measurements of N-acetylaspartate may be a sensitive way to measure selective neuronal loss of patients with hypoxic-ischemic encephalopathy as shown in this single case report.ONA
From Miami Children 's Hospital (N.A.) ; University Hospital, Ann Arbor, Mich (J.A.B.); Bowman Gray School of Medicine, Winston-Salem , NC (A.D.E.);
NYU Medical Center, New York (A.E.G .); Hospital of the University of Pennsylvania, Philadelphia (D.B.H.); UCLA School of Medicine, Los Angeles
(R.B.L.); The Cleveland Clinic Foundation (J.S.R.); The Germantown Hospital and Medical Center, Philadelphia (J .D.S.); University of Pittsburgh School
of Medicine (J .L.W. ); and New England Medical Center Hospital, Boston (S.M.W.).
AJNR 15:1596-1600, Sep 1994 0195-61 08/ 94/1508-1596 © American Society of Neuroradiology
1596
AJNR: 15, September 1994
Hematologic Disorders
Case records of the Massachusetts General Hospital. Weekly clinicopathological exercises: N Eng/ J Med 1994; 330:920-927.
Bilateral epistaxis, retinal hemorrhages , and bilateral central-retinal-vein occlusions were among the clinical manifestations of "hyperviscosity syndrome." Plain films of skull and hip showed lytic foci. "A diagnostic procedure was performed": monoclonal protein identified in blood and urine clinched the diagnosis of (did you guess?) multiple myeloma .DJLW
Inflammatory Disease
Drobyski WR, Knox KK, Majewski D , Carrigan DR. Brief report: fatal encephalitis due to variant B human herpesvirus-6 infection in a bone marrow-transplant recipient. N Eng/ J Med 1994;330:1356-1360.
This is the first documentation of central nervous system infection by human herpesvirus-6. Autopsy revealed damage to astrocytes and myelin in frontal white matter, and to neurons in hippocampus gray matter. Other herpesvirus infections have a propensity for the limbic system. Unfortunately , no imaging studies are included.D JLW
Gilden DH. Herpes zoster with postherpetic neuralgiapersisting pain and frustration. N Eng/ J Med 1994;330: 932-933.
Postherpetic neuralgia is pain in one to three dermatomes after resolution of cutaneous herpes zoster in the same distribution. Ongoing ganglion inflammation (zoster sine herpete) may cause postherpetic neuralgia . Current doses of oral acyclovir are not effective, but higher oral doses, or intravenous therapy, may attenuate or eliminate the pain. Good news for sufferers .DJLW
Mandible and Maxilla
Eisele DW, Richtsmeier WJ, Graybeard JC , Koch WM, Zinreich SJ. Three-dimensional models for head and neck tumor treatment planning. Laryngoscope 1994; 104:433-439.
Plastic mandibular models generated by three-dimensional computed tomography (CT) reconstruction and dental impression type models of the maxilla were each evaluated for usefulness for the head and neck surgeon. The first type was expensive and technologically intensive and the second type was simple but limited. Both models were valuable in certain clinical situations and both had disadvantages of cost, time, and possible inaccuracies caused by image artifacts.DRBL
ANNOTATED BIBLIOGRAPHY 1597
Kuppersmith RB, Disher MJ, Deveikis JP, Frey K, Shulkin BL, Clevens RA, Wolf GT. Management of an osteogenic sarcoma of the maxilla. Ann Otol Rhino/ Laryngol 1994; 103:408-412.
Radionuclide bone scan, coronal CT, coronal pre- and postcontrast T1-weighted MR, anteroposterior angiogram, and a positron emission tomography scan are used to illustrate this lesion . Approximately 10% of all osteosarcomas are found in the head and neck region, most often in the mandible or maxilla. All maxillary osteosarcomas are believed to arise in the alveolar ridge. This case occurred in a 35-year-old man with a 115-pack per year smoking history who had undergone loca l excis ion of a sma ller tumor 2 years before.D JDS
Neck and Nasopharynx Kerner MM, Bates ES, Hernandez F, Mickel RA. Carcinoma-in-situ occurring in a Zenker's diverticulum. Am J Otolary ngol 1994; 15 ( 3): 223-226.
Zenker Pharyngoesophageal Diverticulum results from an outpouching in the inferior constrictor muscle known as Killian Dehiscence. The authors present the sixth reported case of carcinoma-in-situ occurring within a Zenker diverticulum. They emphasize that cigarette smoking, hemoptysis , previous upper-aerodigestive-tract malignancy , and a prolonged history of the diverticulum have been identified as risk factors.D JDS
Stack MC, Ridley MB. Spontaneous cervical emphysema in a child. Otolaryngol Head Neck Surg 1994;110:318-323.
This is a long, mistitled case report of a ch ild who (presumably) performed repeated Valsalva maneuvers , causing alveolar rupture. The authors state that all "spontaneous" cervical emphysema has a cause " if closely studied. " Their bias is apparent: this is really an article on various causes of cervical emphysema. Captions for the two plain films (neck, chest) and lung-window CT images (neck, chest) describe arrows pointing to the emphysema, but the arrows are nowhere to be seen.D JLW
Mori H, Nishimura Y, Satomi F, Mohri D, Kumoi T. Reconsideration on the hyoid syndrome. Otolaryngol Head Neck Surg 1994;110:324 -329.
The authors present four cases, illustrated with three CT images and one xeroradiograph. Each case (and figure) purports to show an abnormally prominent greater cornu of the hyoid. All patients had the offending greater cornu removed , with relief of symptoms. Nonetheless, "hyoid greater cornu" syndrome, caused by irritation of the sympathetic plexus around carotid artery or sinus branch of glossopharyngeal nerve, remains unconvincing .D JLW
Deutsch ES, Milmoe G. Stridor in an adolescent: an unusual symptom. Otolaryngol Head Neck Surg 1994; 110: 330-332.
New-onset stridor in adolescents is rare. A 14-year-old with stridor had a tracheal papilloma diagnosed on MR (one sagittal image), fiberoptic bronchoscopy, and frozensection pathology . The final pathologic diagnosis was mucoepidermoid carcinoma of the trachea, which is rare, and occurs most frequently in teenagers and young adults. Another item for your "laundry list."D JLW
1598 ANNOTATED BIBLIOGRAPHY
Goepfert H, Callender DL. Differentiated thyroid cancerpapillary and follicular carcinomas. Am J Otolaryngol 1994;15:167-179.
More than 90% of thyroid carcinomas are well-differentiated. This is a thorough review emphasizing the pathogenesis , diagnosis , and treatment of these lesions. Much of the information in this thorough review is highly pertinent to contemporary head and neck radiology .OJDS
Ophthalmologic Radiology
Zagelbaum BM, Hersh PS, Donnenfeld ED, Perry HD, Hochman MA. Occasional notes: ocular trauma in majorleague baseball players. N Eng/ J Med 1994;330: 1022-1023.
This (unintentionally?) amusing study presents important findings. A 1-year prospective study found 24 eye injuries in 21 major-league players, or 1.9 eye injuries per 100,000 "player-innings." Batted balls, eye-rubbing, foreign bodies, and the shortstop's knee accounted for most of the injuries. Of the 21 players , only one wore safety glasses! These players ' potential to influence eye-protection habits by setting a (good) example is (as it were) overlooked .DJLW
Nose, Paranasal Sinuses, Face, and Oral Cavity
Ferguson BJ . Fibrous dysplasia of the paranasal sinuses. Am J Otolaryngo/1994;15:227-230.
Fibrous dysplasia involving the paranasal sinuses is a rare subset of craniofacial fibrous dysplasia . Medullary bone is replaced by structurally unsound fibroosseous tissue. This may result in recurrent infections, mucocele formation, nasal airway obstruction, and facial pain. An excellent and well-illustrated review presenting two original cases clearly defined with high quality CT scans.O JDS
Pediatric Neuroradiology
Torres CT, Rebsamen S, Silber JH , et al. Surveillance scanning of children with medulloblastoma. N Eng/ J Med 1994;330:892-895.
This retrospective study compared "surveillance scanning" (CT, MR) to history and physical examination for detecting tumor recurrence after therapy for medulloblastoma (posterior fossa primitive neuroectodermal tumor). Of 86 children , four (clinically asymptomatic) recurrences were detected by scans, and 19 recurrences were detected clinically. One problem with the study is that MR, introduced during the study period ( 1980-1991), might have detected disease missed on CT. The authors acknowledge this . Their conclusion, that surveillance scanning has limited clinical value, is debatable , because they studied a tumor for which cure after recurrence is, in their words , "rare."OJLW
AJNR: 15, September 1994
Lee N, Radtke RA, Gray L, et al. Neuronal migration disorders: positron emission tomography correlations. Ann Neural 1994;35:290 -297 .
The extent of neuronal migration disease is important in surgical planning for epilepsy patients because the best prognosis is seen when the lesion and epileptogenic region are completely removed. lnterictal FOG-positron emission tomography findings were correlated with MR findings in 17 epileptic patients with neuronal migration disorders. Fifteen patients with abnormal MR findings had focal hypometabolic regions in nine cases and a unique finding of displaced metabolic activity of normal gray matter in six cases. Three of the nonhypometabolic cases showed larger lesions on positron emission tomography than on MR.ONA
Renowden SA, Squier M. Unusual magnetic resonance and neuropathological findings in hemimegalencephaly: report of a case following hemispherectomy. Dev Med Child Neural 1994;36:357-369.
Neuropathologic tissue obtained at the time of hemispherectomy from a 15-year-old with hemimegalencephaly and persisting seizures is correlated with MR imaging alteration.OJAB
Cohen M, Roessmann U. In utero brain damage: relationship of gestational age to pathological consequences. Dev Med Child Neural 1994;36:263-170.
Two episodes of intrauterine asphyxia are correlated with neuropathologic findings and with a review of the literature. Although intensity and duration of asphyxia is difficult to characterize, insults occurring before 24 weeks of gestation had bilateral pallidal necrosis as a common feature, while an insult between 26 and 34 weeks of gestation was commonly associated with thalamic and brainstem necrosis . No images are included.OJAB
Moller JR, Trapp BD, Schiffmann R, et al. Childhood ataxia with diffuse central nervous system hypomyelination. Ann Neuro/1994;35:331-340.
Four patients demonstrate diffuse white matter disease of the cerebrum and parts of the cerebellum on CT and MR examinations with minimal clinical findings . Progressive clinical leukodystrophy was identified without abnormalities found in the evaluation for known metabolic and degenerative diseases. This progression was not reflected on the MR or CT examinations. MR spectroscopy demonstrated marked decrease in the N-acetylaspartic acid , choline , and creatine of the white matter relative to gray matter. This appeared to be specific in this distinct clinical pathological syndrome, because it has not been previously reported in other white matter diseases.ONA
Phakomatoses
North K, Joy P, Yuille D, et al. Specific learning disability in children with neurofibromatosis type 1: significance of MRI abnormalities . Neurology 1994;44:878-883.
An interesting paper. Patients with neurofibromatosis type 1 and focal areas of high intensity on T2-weighted MR had a much higher risk for impaired academic achievement than patients with neurofibromatosis type 1 who did not have the T2 changes. Furthermore, the frequency of learning disability in the neurofibromatosis population was much higher than that expected for the general population .DSM W
AJNR: 15, September 1994
Seizure Disorders
Cendes F, Andermann F, Preul MC, Arnold DL. Lateralization of temporal lobe epilepsy based on regional metabolic abnormalities in proton magnetic resonance spectroscopic images. Ann l'leurol 1994;35:211-216.
Lateralization of temporal lobe epilepsy of 10 patients who had surgical treatment of medically intractable epilepsy was compared with findings in 5 healthy control subjects using the reduced N-acetylaspartate-to-creatine ratio . This ratio showed agreement with the side of clinicalelectroencephalogram lateralization and MR abnormalities in all cases. One patient had no MR abnormalities but showed MR spectroscopy abnormalities confirmed pathologically as mild hippocampal sclerosis , suggesting that MR spectroscopy may be able to show neuronal loss in these patients with a greater sensitivity than MR.D NA
Cook MJ . Mesial temporal sclerosis and volumetric investigations. Acta l'leurol Scand Suppl 1994;89 (152):109-114.
This paper, in an Acta l'leurologica volume devoted to epilepsy surgery, regards the value of volumetric MR examination of the mesial temporal lobe structures in patients with clinical temporal lobe seizures. Numerous papers on the neurophysiology, value of subdural electrodes, magnetic source imaging , MR, and functional changes including positron emission tomography in patients with temporal lobe problems are discussed in this volume.DSMW
Kitchen ND, Thomas DGT, Shorvon SD, Fish DR, Stevens JM. Volumetric analysis of epilepsy surgery resections using high resolution magnetic imaging: technical report. BrJ l'leurosurg 1993;7:651-656.
A technique for obtaining accurate baseline postoperative examinations with a volumetric MR technique was used in 25 patients. This method lends itself to further work to' evaluate the efficacy of lesionectomy versus an en-bloc resection as related to the volume of brain removed and the long-term functional follow-up .D NA
Jack CR, Mullan BP, Sharbrough FW, et al. Intractable nonlesional epilepsy of temporal lobe origin: lateralization by interictal SPECT versus MRI. Neurology 1994;829-836.
The authors found that MR of the temporal lobe is more accurate than single-photon emission CT in providing accurate seizure lateralization. More specifically , hippocampal volume measurements correctly lateralized seizures in 86% of cases, whereas single-photon emission CT correctly lateralized seizures in 45% of cases.D SMW
Jackson GD, Connelly A, Cross JH, Gordon I, Gadian DG. Functional magnetic resonance imaging of focal seizures. l'leurology 1994;44:850-856.
An interesting case report of a patient with seizures studied with a conventional 1.5T MR system with a flash sequence. The images acquired every 10 seconds in blocks of 60 images were obtained during clinical seizures and showed sequential activation associated with specific gyri.DSMW
ANNOTATED BIBLIOGRAPHY 1599
Garcia PA, Laxer KD, van der Grond J , et al. Phosphorus magnetic resonance spectroscopic imaging in patients with frontal lobe epilepsy. Ann 1'/euro/1994;35 :217-221.
Phosphorus MR single-photon emission CT was used in e ight patients with frontal lobe ep il epsy determined by ictal electroencephalogram recordings and with normal MR findings . Within the epileptogenic frontal lobe the mean pH was significantly increased in five patients compared with the contralateral frontal lobe and with control subjects. The phosphomonoester levels were decreased asymmetrically, correctly lateralizing the frontal ep ileptogenic foci in seven of eight patients. The mean inorganic phosphate levels failed to provide lateralizing informa tion , because they were not consistently increased within the epileptogenic focus as in patients with temporal lobe epilepsy .DNA
Spine Ditunno JF, Forma CS. Current concepts: chronic spinal cord injury. 1'1 Eng/ J fVled 1994;330:550-557.
The authors of this interesting paper are rehabilitation physicians. They discuss pathophysiology , manifesta tions , and management of complications encountered both in the second year and more than 30 years after spinal cord injury. Psychosocial issues include employment, sexual function, parenthood, aging , and life satisfaction . These are important clinical correlates of conditions neuroradiologists often diagnose without pausing to consider the ramifications.D JLW
Zimmerman GA, Weingarten K, Lavyne MH . Symptomatic lumbar epidural varices: report of two cases. J 1'/eurosurg 1994;80:914-918.
Describes a rare cause of back pain with good imaging findings , color operative photos, and discussion. I had never heard of this entity until I encountered my first case about 3 years ago.DADE
Barnsley L, Lord SM, Wallis BJ , Bogduk N. Lack of effect of intraarticular corticosteroids for chronic pain in the cervical zygoapophyseal joints. 1'1 Eng/ J fVled 1994;330: 1047-1050.
Patients with chronic neck pain after whiplash underwent a therapeutic trial injection of local anesthetic into dorsal rami supplying cervical zygoapophyseal joints. If their pain diminished, they were randomized into a group that received bupivacaine or a group that received betamethasone (local anesthetic or steroids introduced into zygoapophyseal joints under fluoroscopic guidance) . Duration of pain relief was 3.5 days for bupivaca ine, 3.0 days for betamethasone. The authors conclude that intraarticular steroid therapy is not worth the risk and radiation exposure. The study is nicely designed, the discussion is thoughtful and thought-provoking .DJLW
Carette S. Whiplash injury and chronic neck pain. 1'1 Eng/ J fVled 1994;330: 1083-1084.
This accompanying editorial provides some interesting statistics on "late whiplash syndrome ." The a uthor firmly states that there is now enough evidence that steroid injection into apophyseal joints is ineffective. He believes the practice should be stopped, perhaps by discontinuing third-party reimbursement. An unexpected proposal! D JLW
1600 A NNOTATED BIBLIOGRAPHY
Stroke J ansen C, Ramos LMP, van Heesewijk JPM, Moll FL, van Gijn J , A ckerstaff RGA. Impact of microembolism and hemodynamic changes in the brain during carotid endarterectomy. Stroke 1994;25:992-997 .
Pre- and postoperative CT or MR was monitored in patients undergoing carotid endarterectomy, with monitoring of the endarterectom y with transcranial Doppler. There was a significant correlation between the number of embolic signals during surgica l dissection of the carotid artery and occurrence of intraoperative infarcts . Two MR figures . O JSR
Grasso MG , Pantano P, Ricc i M , et al. Mesial temporal cortex hypoperfusion is associated with depression in subcortical stroke. Stroke 1994;254:980-985.
Fifteen patients with a single subcortical lesion were evaluated for depression as well as with single-photon emission CT using 99mTc hexam ethylpropyleneamine oxime. A number of flow values were lower in the depressed patients than the nondepressed, only in the mesial temporal cortex of the affected hemisphere . Authors suggest the temporal lobe hyperperfusion reflects dysfunction of the limbic system , which may underlie depressive phenom enology. Two color single-photon emission CT figures .DJ SR
Gideon P, Sperling B , Arli en-Soborg P, Olsen TS, Henriksen 0 . Long -term follow-up of cerebral infarction patients with proton magnetic resonance spectroscopy. Stroke 1994; 25:967-973 .
Six patients with ischemic stroke were evaluated in the acute stage to the chronic stage with proton MR spectroscopy . No clear correlation was found between the level of N-acety laspartate or lactate in the acute stage of stroke and the clini ca l outcome. However, the study group is too sm all to draw any definite conclusions regarding the prognostic information of spectroscopy. O JSR
Temporal Bone Katsarkas A . Dizziness in aging: a retrospective study of 1194 cases. Otolaryngol Head Neck Surg 1994; 110:296-30 1.
This is a frustratingl y vague ret rospective study of 1194 patients who were 70 years or older when first seen at a "dizzyness cl inic." Odd results: 2 1% of patients remained "undiagnosed;" 39% were "strongly suspected" of having paroxysm al pos itional vertigo. "Cardiovascular" causes are included with the 8 .7% with "nonvestibular, non-neurolog ic " disease, but another 6. 3% were diagnosed with "cerebrovascular disease." This distinction is not ex plained. Seventeen patients had tumors: "most" were acousti c neurom as or m eningiomas. It is unclear when (and which ) imaging studies were used. The conclusion restates the introduction. What has been learned?OJLW
AJNR: 15, September 1994
Spingarn AT, Selesnick SH , Minick CR. Inner ear cholesteatoma: an embryologic aberration. Otolaryngol Head Neck Surg 1994; 110:333-337.
This supposed primary cochlear cholesteatoma caused tinnitus, hearing loss, dysequilibrium, and ear pain . The MR (included) showed intense enhancement of the co chlea, vestibule, semicircular canal , and fundus of the internal auditory canal. The CT (included) showed erosion of the otic capsule . (Close examination of the MR suggests erosion of the otic capsule.) This wordy case report discusses hypotheses on the causes of primary cholesteatomas and epidermoids : metaplasia, aberrant differentiation in utero , aberrant migration, aberrant inclusion of epithelium. The authors admit their case remains puzzling. Perhaps this was a middle ear cholesteatoma after all? Perhaps the pathologic diagnosis is inaccurate?O JLW
Kavanaugh KT. Applications of image-directed robotics in otolaryngologic surgery. Laryngoscope 1994; 104:283-292 .
Using image-directed robotics , antrostomies were performed on five human temporal bone specimens. The antrum was reached in all bones. The dura, horizontal canal , sigmoid sinus, and fa cial nerve were not violated in any specimen . The average absolute error in bone removal was 0 .88 mm. The use of a robotic arm with tighter joints and redundant position checking should overcome most of these problems.DRBL
Moreano EH , Paparella MM, Zelterman D, Goycoolea MV. Prevalence of facial canal dehiscence and of persistent stapedial artery in the human middle ear: a report of 1000 temporal bones. Laryngoscope 1994; 104:309 - 320.
A total of 1 000 temporal bones were examined to study the prevalence of facial canal dehiscence and persistent stapedial artery. At least one facial canal dehiscence was present in 56% of the temporal bones most commonly near the oval window. There was a 76% prevalence of bilaterality of this finding . Microdehiscence of the facial canal was present in 75% of specimens with a 40% bilaterality. Persistent stapedial artery was present in 0.48% of the specimens.DRBL
Trauma Young WB , Silberstein SD. Imaging and electrophysiologic testing in mild head injury. Semin Neuro/1994 ;14: 46.
The efficacy of plain skull radiographs , CT, and MR after mild head injury is reviewed with an extensive list of references. Strategies for obtaining imaging studies relative to Glasgow Coma Scale, clinical course, and type of injury are reviewed.D JAB