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Show Journal of Neum- Ophthalmology 17( 4): 2& 2- 290, 1997. © 1997 Lippincott- Raven Publishers, Philadelphia Literature Abstracts Beginning in this issue, we are changing the format of the abstract review. In the past, abstracts were culled from the ophthalmic literature. The fields of neurologic surgery and neuroradiology have developed, to a large extent, based on the localization possible through the use of neuro- ophthalmic studies. As these fields have expanded, neuroradiologists and neurosurgeons often continue to contribute to our knowledge of the central nervous system and visual pathways. We will attempt to review articles of neuro- ophthalmic interest appearing in the neurosurgical and neuroradiologic literature. In this first section we present abstracts from interesting articles appearing over the past 6 months in the major neurosurgical journals. Steven A, Newman, M. D. Bilateral Superior Ophthalmic Vein Enlargement Associated with Diffuse Cerebral Swelling. Report of 11 cases. Khanna RK, Pham CJ, Malik GM, Spickler EM, Mehta B, Rosenblum ML. J Neurosurg 1997; 86: 893- 7 ( May). Superior ophthalmic vein dilatation is often a cardinal sign of a dural cavernous fistula. This is less commonly seen with cavernous sinus thrombosis or other compressive lesions at the orbital apex. The authors report a series of 11 patients with bilateral superior ophthalmic vein enlargement associated with diffuse cerebral swelling. They postulate that cavernous sinus venous stagnation related to increased intracranial pressure could produce venous stagnation and thus enlargement of the superior ophthalmic veins. This syndrome may need to be included in the differential diagnosis of enlarged superior ophthalmic veins. Large Sixth Nerve Neuroma Involving the Prepontine Region- Case Report. Okada Y, Shima T, Nishida M, Okita S. Neurosurgery 1997; 40: 608- 10 ( Mar). Peripheral cranial nerve tumors are relatively uncommon. Although trigeminal neurinomas are not rare, tumors involving the ocular motor nerves ( III, IV, and VI) are very uncommon. The authors report the case of a 54- year- old woman presenting with diplopia and a mass in the prepontine region contiguous with the sixth nerve. Fenestrated Oculomotor Nerve Caused by Internal Carotid- Posterior Communicating Artery Aneurysm: Case Report Horiuchi T, Kyoshima K, Oya F, Kobayashi S. Neurosurgery 1997; 40: 397- 8; discussion 398- 9 ( Feb). The authors report a case of a 48- year- old woman in whom imaging studies demonstrated a right internal carotid posterior communicating artery aneurysm between portions of the third nerve. The patient had presented with a frontal headache and " mild oculomotor paresis." The authors speculated that the aneurysm was responsible for the fenestration. Although this is possible, divisions of the ocular motor nerves is not rare. Studies have indicated that the sixth nerve may divide into branches as it passes through the area of Dorello's canal and me cavernous sinus. Similarly, the third nerve divides into a superior and inferior division in the majority of cases, and it is possible for more proximal separation to cause the appearance of a nerve fenestration. Full Functional Recovery after Surgical Repair of Transected Abducens Nerve- Case Report. Sawa-mura Y, Ikeda J, Miyamachi K, Abe H. Neurosurgery 1997; 40: 605- 7 ( Mar). The authors report a case of complete recovery of abduction following repair of a sixth nerve after sectioning at the time of surgical removal of a petroclival meningioma. The patient reportedly ' ' did not complain'' of diplopia after 9 months and had full ocular motility. Although this case is fairly remarkable in the completeness of sixth nerve recovery ( without residual esodeviation), even partial recovery of sixth nerve function makes the options for realignment much greater than when the sixth nerve palsy remains complete. Interruption of the sixth nerve during surgery at and around the area of the cavernous sinus is not rare, and surgeons should be encouraged to attempt surgical reapproximation of the cranial nerves, particularly the sixth nerve, because even partial recovery will have profound alteration in the ability to achieve useful binocular single vision. Successful Surgical Treatment of Intraorbital Arteriovenous Malformations- Case Report. Hieu PD, Besson G, Roncin S, Nonent M. Neurosurgery 1997; 40: 626- 31 ( Mar). The authors report the case of a 39- year- old woman who presented with pulsatile exophthalmus, visual loss, LITERATURE ABSTRACTS 283 and pain with angiographic evidence of an intraorbital arteriovenous malformation. They approached this lesion through a fronto- orbital craniotomy and excision using the C02 laser. Reportedly, the patient had full recovery of vision and correction of the proptosis. The authors suggested the danger of potential embolization and the usefulness of the surgical approach. This is a fairly remarkable case because dissection within the orbit involving an extensive arteriovenous malformation would seem likely to result in significant morbidity involving, if not acuity, then at least ocular motility. The risk: benefit ratio for approaching vascular lesions within the orbit must be carefully considered. When possible, venous approaches through interventional neuroradiology could potentially play a role. However, this case does remind us of the possibility of surgical treatment for arteriovenous lesions. / Orbital Venous Drainage into the Anterior Cavernous Sinus Space- Microanatomic Relationships. Spektor S, Pionpk E, Umansky F. Neurosurgery 1997; 40: 532- 8 ( Mar)\ Along with A\ Rhoton's interest in basic microanatomy, Dr. Umarkky's group in Israel has had a longstanding interest in the microanatomy of the cavernous sinus. In this anatomic\ dissection study of 24 specimens, they carried the dissection forward to observe the orbital venous drainage into theWterior cavernous space. They noted the entrance of the inferior vein into the superior ophthalmic vein before draining into the cavernous sinus through the superior orbital Fissure. This was located in front of the anterior genu of the intracavernous segment of the internal carotid artery\ The anatomy of the cavernous sinus remains a fascinating area, and because it represents more of an extension of the orbit extradurally than an intracranial area, it \ s important for neuro-ophthalmologists to be familiar with the anatomic arrangements. Electrophysiological Investigation of Hemifacial Spasm after Microvascular Decompression; F Waves of the Facial Muscles, Blink Reflexes, and Abnormal Muscle Responses. Ishikawa M, Ohira T, Namiki J, Kobayashi M, Takase M, Kawase T, Toya S. / Neuro-surg 1997; 86: 654- 61 ( Apr). The etiology of hemifacial spasm has been presumed due to stimulation of the seventh nerve as it exits the brain stem. This compression at the root exit zone, usually due to a tortuous branch of the vertebrobasilar system, results in an abnormal loop conduction associated with ephaptic transmission ( axon- to- axon stimulation). The so called F waves resulting from the backfiring may be measured electrophysiologically. In this study of 20 patients undergoing microvascular decompression, the F waves gradually resolved. This lends credence to the presumed pathophysiology of hemifacial spasm and also points out the relatively slow resolution of these electrophysiologic abnormalities ( over a period of months) once the nerve is decompressed. Because of this slow recovery, the authors have recommended that additional intervention not be undertaken for 2 years after microvascular decompression. Attenuation of Ischemia- Reperfusion Injury in the Rat Neocortex by the Hydroxyl Radical Scavenger Nicaraven. Toyoda T, Kassell NF, Lee KS. Neurosurgery 1997; 40: 372- 7; discussion 377- 8 ( Feb). Several factors are currently undergoing evaluation as the possible " second messenger" in damage produced by ischemic injury. These have included oxygen free radicals which are felt to play a major role in the ischemic reperfusion injury occurring after vascular occlusion. Nicaraven, a hydroxyl radical scavenger, was used in 58 rats subject to transient focal ischemia by occluding both carotid arteries and one middle cerebral artery for 3 h. Subsequent brain edema was monitored with and without infusion of the nicaraven. There was reduction of infarct size with both pre- and posttreatment. Although the numbers are still somewhat limited and the effect is obviously only partial, these lend credence to believe that oxygen free radical scavengers may play a role in reducing cerebral injury after ischemia. It is possible that these medications also may play a role in protecting the optic nerve and other parts of the visual system when subject to ischemic reperfusion injury. Regeneration of Injured Axons in the Adult Mammalian Central Nervous System. Tatagiba M, Brosamle C, Schwab ME, Neurosurgery 1997; 40: 541- 6 ( Mar), Axonal regeneration after injury has been a major impediment to recovery after injury to the optic nerve. This study reviews the current understanding of the role of myelin- associated proteins in the central nervous system white matter to act as inhibitors to the regrowth of nerve fibers. Neutralization of these proteins through monoclonal antibodies have been used in the rat model of spinal cord injuries to increase axonal regeneration. It is possible that these techniques may have applicability to the optic nerve as well. Improvement of Cognitive Deficits and Decreased Cholinergic Neuronal Cell Loss and Apoptotic Celt Death Following Neurotrophin Infusion after Experimental Traumatic Brain Injury. Sinson G, Perri BR, J Neuro- Ophihahnot. Vol 17, No. 4. 1997 284 LITERATURE ABSTRACTS Trojanowski JQ, Flamm ES, Mcintosh TK. J Neurosurg 1997; 86: 511- 8 ( Mar). Recent work suggests that the final common pathway for damage to central nervous system neurons, especially with long axonal projections, may well be apoptotic programmed cell death. This is particularly true in the optic nerve. Attempts at modifying the normal cascade pathway initiated by multiple insults to the central nervous system have included the use of nerve growth factor. In this experimental study, nerve growth factor was instilled direcdy into the ventricular system of rats injured by a fluid percussive brain injury. Clinically, rats treated with nerve growth factor infusion performed better, suggesting improved cognitive functioning compared to controls with infusion of vehicle only. In addition, pathologic examination showed evidence of apoptotic cell loss in the septal region. These preliminary data suggest that nerve growth factor infusion may alter the apoptotic pathway leading to central nervous system cell injury. The implications to its use in treatment of optic nerve injury remain to be explored. Prospective Study of Zero Drift in Fiberoptic Pressure Monitors Used in Clinical Practice. Bavetta S, Norris JS, Wyatt M, Sutcliffe JC, Hamlyn PJ. / Neurosurg 1997; 86: 927- 30 ( Jun). Intracranial pressure may be determined by a lumbar puncture. Unfortunately, cerebrospinal fluid pressure can be very variable, and normal pressure at one point does not exclude the possibility of pressure spikes that may cause symptomatic problems. Continuous monitoring of intracranial pressure is possible with implantation of a catheter system through a small twist drill or burr hole. The earliest systems required a manometer or pressure gauge that was sensitive to positioning of the measuring apparatus. More recently, so- called zero drift fiberoptic pressure monitors have been adapted to give a continuous readout of intracranial pressure. These may be placed either subdurally or transventricularly. In this study of 101 fiberoptic pressure transducers in 86 patients, the authors report complications in four, including two transient cerebrospinal fluid leaks after removal and two insignificant intracerebral hematomas. Technical problems with the catheter occurred in 23 cases, with 11 devices ceasing to function before removal, seven becoming displaced, and five microventricular catheters failing to enter the ventricles. There was also a reported negative bias in the readings suggesting that current zero drift catheters may have some nonreproducibility in pressure readings. The authors go on to suggest that at this time undue reliance should not be placed on intracranial pressure readings from these devices without additional confirmatory data. It is likely with time that continued improvement and monitoring techniques will make this form of continuous pressure monitoring more commonplace. This will be particularly useful in patients with presumed pathology ( the optic neuropathy of increased intracranial pressure) related to persistent or transient intracranial pressure elevation. Craniopharyngioma Arising De Novo in Middle Age- Case Report. Arginteanu MS, Hague K, Zimmerman R, Kupersmith MJ, Shalu JH, Schaffer J, Post KD. J Neurosurg 1997; 86: 1046- 8 ( Jun). Craniopharyngiomas are felt to arise from remnants of Rathke's pouch and sac. Although these may grow throughout life and may not present until middle age, their origin has been presumed due to hamartomatous tissue rests. In this case report of a 55- year- old patient, a symptomatic craniopharyngioma developed within 2 years of obtaining a normal magnetic resonance image of her head. This suggests that these tumors may arise de novo and therefore challenges the accepted understanding of tumor production. Intravascular Papillary Endothelial Hyperplasia of the Sellar Region. Report of Three Cases and Review of the Literature. Kristof RA, Van Roost D, Wolf HK, Schramm J. J Neurosurg 1997; 86: 558- 63 ( Mar). The authors report a rare syndrome that may produce lesions in the cavernous sinus mimicking other forms of cavernous sinus pathology. In three cases, intravascular papillary epithelial hyperplasia ( considered a reactive proliferation of endothelium associated with thrombosis) originated from the cavernous sinus and extended into the sella. Recognition is important because these lesions may respond to surgery or radiotherapy. Isolation and Characterization of Human Malignant Glioma Cells from Histologically Normal Brain. Sil-bergeld DL, Chicoine MR. J Neurosurg 1997; 86: 525- 31 ( Mar). Successful cure of tumors of the glioma group are uncommon. This is particularly true for those of higher grade. In this study of four patients ( two who underwent frontal and two temporal lobe surgery for gliomas), neoplastic glial cells could be grown in cell cultured from areas of grossly normal brain more than 4 cm away from the tumor. This would suggest that tumors of the glial cell line may invade far more extensively than previously appreciated, helping to explain the poor surgical results. It is likely that surgery alone will end up playing a less, rather than more, important role in the care of these patients. J Neuro- Ophthalmol. Vol. 17, No. 4, 1997 LITERATURE ABSTRACTS 285 Juvenile Active Ossifying Fibroma. Report of Four Cases. Lawton MT> Heiserman JE, Coons SW, Ragsdale BD, Spetzler RR J Neurosurg 1997; 86: 279- 85 ( Feb). Fibro- osseous disorders are a fascinating collection of lesions related to abnormal bone maturation. Most authors have dropped the distinction between ossifying fibroma and fibrous dysplasia, although some still feel that there are distinctive elements. Lesions often involve the juvenile population ( prepubertal) frequently resulting in displacement of the globe. This leads to abnormalities in the craniofacial skeleton but can also result in periorbital pain, headache, secondary sinusitis, and compression of the contents at the orbital apex resulting in decreased visual acuity. In this report, four patients experienced high- grade internal carotid artery stenosis with secondary ischemic symptoms. These symptoms are quite unusual. Unfortunately, I think the authors may be a bit optimistic about curing these patients based on the results of 2 years of follow- up. There is a very high incidence of recurrent problems with bone maturation even after surgical resection. Previous literature suggesting that these lesions stop growing at puberty seem to be overly optimistic, and late continued grown of fibro-osseous disorders is not uncommon. Skull Base Chordomas: A Management Challenge. al- Mefty O, Borba LA. J Neurosurg 1997; 86: 182- 9 ( Feb). Chordomas, along with chondrosarcomas, form one of the fascinating groups of tumors involving the skull base. Treatment results have been less than ideal, with an extremely high rate of recurrence. In this report the authors document treatment in 25 patients undergoing 33 surgical procedures. Reported radical removal was achieved in 10 patients, with subtotal resection in 11. Unfortunately, the series suffers from relatively short- term follow- up, and even with adjunctive proton beam radiation these tumors can prove extremely difficult to eradicate. Their surgical morbidity was low, and it is important to consider balancing the potential risks of aggressive treatment in these often slow- growing lesions that have been extremely difficult to cure. Lymphocytic and Granulomatous Hypophysitis- Experience with Nine Cases. Honegger J, Fahlbusch R, Bornemann A, Hensen J, Buchfelder M, Muller M, Nomikos P. Neurosurgery 1997; 40: 713- 22 ( Apr). Lymphocytic hypophysitis and granulomatous hypophysitis have made it to the Walsh meeting on more than one occasion. These inflammatory lesions affecting the pituitary gland may get large enough to cause visual symptoms by compressing the optic nerve or chiasm. In this fairly extensive series of six cases of lymphocytic hypophysitis, two cases of granulomatous hypophysitis, and one case with both, headache or evidence of aseptic meningitis was found in all patients. It is interesting that two of their nine patients were reported to have ' ' restriction" of the visual fields and one described visual deterioration. It is not clear that all patients were examined prospectively from a neuro- ophthalmic point of view. The magnetic resonance findings are well characterized, including hyperintensity or patchy enhancement in all but two, one of whom had no magnetic resonance imaging results available. These nine cases remain uncommon because they were derived from a surgical series of 23,062 pituitary lesions. The authors seem somewhat biased to a direct surgical approach, arguing that steroid therapy often resulted in recurrence after tapering or withdrawal. Reduced Expression of Schwannomin/ Merlin in Human Sporadic Meningiomas. Lee JH, Sundaram Y, Stein DJ, Kinney SE, Stacey DW, Golubic M. Neurosurgery 1997; 40: 578- 87 ( Mar). The gene responsible for NF2 ( neurofibromatosis type 2) recently was identified. This gene has been found to be mutated in patients with sporadic meningiomas as well. The protein product of the NF2 gene has been referred to as schwannomin or merlin. The authors report the results of immunoblot study for expression of schw-annomin/ merlin in 14 cases with sporadic meningiomas. Levels of schwannomin/ merlin were severely reduced in 57% of these tumors compared with expression in the normal human brain. The authors postulate that the occurrence of mutations within the NF2 gene leading to decreased production of this protein may play a pathophysiologic role in development of over 50% of sporadic meningiomas. Clonality of Multiple Meningiomas. Stangl AP, Wellenreuther R, Lenartz D, Kraus JA, Menon AG, Schramm J, Wiestler OD, von Deimling A. J Neurosurg 1997; 86: 853- 8 ( May). Multiple meningiomas are common. Recent advances in molecular genetics suggest that one mechanism for producing multiplicity in meningiomas would be loss of the suppressant effect of the product of the NF2 gene. Ten of 12 patients with multiple meningiomas in this study demonstrated abnormalities in DNA consistent with NF2 gene mutations. In addition, clonality studies of these lesions suggested a common clonal origin in all four patients containing more than two meningiomas. The authors postulate cerebrospinal fluid seeding as a possible explanation for this common clonality. This J Neure- Optitlmlmo!, Vol. 17. No. 4, 1997 286 LITERATURE ABSTRACTS could be an additional cause of apparent recurrence as well as multiplicity in meningiomas. Progesterone and Estrogen Receptors in Meningiomas: Prognostic Considerations. Hsu DW, Efird JT, Hedley- Whyte ET. J Neurosurg 1997; 86: 113- 20 ( Jan). The observation that meningiomas often grow during pregnancy led investigators to study meningiomas for the possible existence of steroid hormone receptors. Both estrogen and progesterone receptors have been discovered on meningiomas, although there has been an unfortunate poor correlation between receptor presence and clinical outcome. In this study, 70 patients were evaluated immunocytochemically for female sex hormone receptors using monoclonal antibodies. Eighty- three percent were positive for progesterone receptors, but only 9% for estrogen receptors. In the study, absence of progesterone receptors was, along with high mitotic index and higher tumor grade, associated with shorter disease-free interval. This does suggest that the presence of progesterone receptors may be a favorable prognostic factor for meningiomas. Unfortunately, attempts at manipulating the steroid hormone receptors in meningiomas so far has produced less than ideal results. Percutaneous Biopsy of Cavernous Sinus Tumors Through the Foramen Ovale. Sindou M, Chavez JM, Saint Pierre G, Jouvet A. Neurosurgery 1997; 40: 106- 10; discussion 110- 1 ( Jan). Skull base lesions are increasingly accessible to surgical intervention. However, these cases require a substantial commitment and have a significant potential morbidity and even mortality. The likelihood of success depends greatly on the type of lesion encountered; therefore, preoperative knowledge of the exact histology can be extremely useful. In this study, aspiration biopsy samples were obtained in 13 patients with cavernous sinus lesions through the foramin ovale. The authors report an accuracy of 84% with no complications. Diagnosis of Brain Abscess by Magnetic Resonance Spectroscopy. Report of Two Cases. Martinez- Perez I, Moreno A, Alonso J, Aguas J, Conesa G, Capdevila A, Arus C. J Neurosurg 1997; 86: 708- 13 ( Apr). The initial promise of magnetic resonance imaging scanning included the possibility of spectral analysis. Although we have seen dramatic improvement in imaging, there has been little literature on the clinical significance of spectral assessment. In this clinical report, magnetic resonance spectroscopy was used in two cases to demonstrate unique features in a brain abscess. The appearance of an abscess can mimic other cystic lesions, including neoplasia. Further development of spectral analysis seems to hold the potential of more definitive noninvasive diagnosis. Brain Stem Involvement in Children with Neurofibromatosis Type 1: Role of Magnetic Resonance Imaging and Spectroscopy in the Distinction from Diffuse Pontine Glioma, Broniscer A, Gajjar A, Bhargava R, Langston JW, Heideman R, Jones D, Kun LE, Taylor J. Neurosurgery 1997; 40: 331- 7; discussion 337- 8 ( Feb). Magnetic resonance spectroscopy, although one of the leading potential applications of magnetic resonance to imaging, has of yet had limited clinical application. In this study, magnetic resonance spectroscopy had distinctive patterns in patients with brain stem involvement in NFl. These lesions could be distinguished from pontine gliomas. Hopefully, spectroscopy will play an increasing role in the ability to identify specific tumor types. Preliminary Results on the Management of Unruptured Intracranial Aneurysms with Magnetic Resonance Angiography and Computed Tomographic Angiography. Harrison MJ, Johnson BA, Gardner GM, Welling BG. Neurosurgery 1997; 40: 947- 55 ( May). With increasing resolution available in magnetic resonance imaging ( MRI) and magnetic resonance angiography ( MRA), there has been an attempt to replace digital angiography with the data supplied by MRA or dynamic CV spiral computed tomographic angiography ( CTA). In 10 patients undergoing MRA and CTA for " suspected unruptured aneurysms," aneurysms were seen in eight. An additional two patients had aneurysms uncovered by angiography for transient ischemic episodes. Standard digital subtraction angiography was not performed in six of these 10 patients, and surgical repair was offered to five patients based on the results of MRI, MRA, and CTA. Three patients had additional vascular lesions including internal carotid artery stenosis in two and a right carotid cavernous fistula and left cavernous carotid aneurysm in one. Resolution of these techniques is now approaching 3 mm. An argument can be made that the patients may be managed based on the imaging studies alone. Additional data are likely to be necessary before most institutions are comfortable with this approach. Transmaxillary Approach to the Anterior Cavernous Sinus- A Microanatomic Study. Couldwell WT, Sabit J Neuro- Ophlhalmoi. Vol. 17, No. 4, 1997 LITERATURE ABSTRACTS 287 I, Weiss MH, Giannotta SL, Rice D. Neurosurgery 1997; 40: 1307- 11 ( Jun). Lesions of the cavernous sinus have been traditionally difficult to approach. Their location at the skull base in intimate contact with the distal internal carotid artery as well as the third, fourth, fifth, and sixdi cranial nerves has made surgical approach difficult and morbidity high. In this cadaver study, the audiors suggest an additional approach to die cavernous sinus through a sublabial max-illectoray and dissection along the course of die infraorbital nerve through the pterygomaxillary area. This offers an additional extradural approach to the area of the cavernous sinus, particularly for diose lesions that involve the second division of the fifth cranial nerve. The potential problems include the presence of the distal internal maxillary artery within the pterygomaxillary area as well as the parasympathetics of the sphenopalatine ganglion. Interruption here results in decreased parasympathetic innervation to the lacrimal gland and a relative decrease in reflex tearing. This " inferior orbital fissure syndrome" may be a small price to pay for access to lesions in this location. Extradural surgery offers sizable advantages when possible. Endoscopic Transseptal Transsphenoidal Surgery for Pituitary Tumors. Yaniv E, Rappaport ZH. Neurosurgery 1997; 40: 944^ 6 ( May). Endoscopic techniques have recently been widely accepted in otolaryngology/ head and neck surgery. These offer significant advantages for approaching lesions within the nasal cavity and paranasal sinuses. In this report of 14 consecutive patients, the authors have used nasal endoscopes to take down the anterior face of the sphenoid sinus before transsphenoidal surgery. Other authors have performed die entire procedure endoscopi-cally. Endoscopes provide detailed information as well as the ability to operate through smaller areas. Optimal use of these instruments, however, requires practice and experience as well as detailed anatomic knowledge. Complications with endoscopy are not rare and may involve the carotid artery as well as the optic nerves and medial contents of me orbit. Complications of Transsphenoidal Surgery: Results of a National Survey, Review of the Literature, and Personal Experience. Ciric I, Ragin A, Baumgartner C, Pierce D. Neurosurgery 1997; 40: 225- 36; discussion 236- 7 ( Feb). This report includes the results of a survey mailed to 3,172 neurosurgeons regarding complications of transsphenoidal surgery. The audiors hope to provide incidence of complications and a possible relationship to previous experience. Nine hundred fifty- eight respondents who reported performing me operation were analyzed. These were broken into groups based on experience (< 200 operations, 100- 500 operations, or > 500 operations). As anticipated, there was an inverse correlation between experience and complication rate. The authors did point out the potential for misinterpretation because of its basis on the respondent's recollections. Experience did not preclude complications, and even in the hands of me most experienced surgeons, transsphenoidal surgery still ran an incidence of complications of 1- 3%. Anterior pituitary dysfunction and diabetes insipidis represented the most frequent complications occurring in almost 20% of cases. Results of Surgery for Head and Neck Tumors that Involve the Carotid Artery at the Skull Base- Brisman MH, Sen C, Catalano P. / Neurosurg 1997; 86: 787- 92 ( May). In a retrospective review of 17 patients with head and neck malignancies undergoing skull base surgery for lesions involving the carotid artery, patients who underwent carotid resection widiout bypass did substantially more poorly man those with revascularization procedures or in whom the carotid was spared. Although the numbers were small, this study does emphasize the risk of stroke when the carotid is sacrificed without revascularization. The authors would argue that the improved prognosis, even in patients with malignancies, justifies the effort required to bypass the carotid if it cannot be spared. Magnetic Resonance Imaging of Obliterated Arteriovenous Malformations up to 23 Years after Radiosurgery. Kihlstrom L, Guo WY, Karlsson B, Lindquist C, Lindqvist M. J Neurosurg 1997; 86: 589- 93 ( Apr). Focal radiotherapy ( stereotactic radio surgery, gamma knife, LINAC) has become increasingly popular over die past few years. The indications for use of these techniques remains undefined, as do the long- term results in treated patients. This report from die gamma knife group in Sweden gives some of the longest follow- up available on patients treated witii focal stereotactic radiosurgery. In 18 patients with arteriovenous malformations ( AVM's) treated with a gamma knife followed for 8- 23 years, 28% developed cyst formation at die sight of the obliterated AVM. In addition, 61% of the patients were seen to have contrast enhancement on magnetic resonance scanning. These data will prove to be important in recognizing the expected long- term changes in patients treated with gamma knife therapy. J Neuro- Ophihalmol, Vol. 17, No. 4, 1997 288 LITERATURE ABSTRACTS The Surgical Resectability of Meningiomas of the Cavernous Sinus. O'SuIlivan MG, van Loveren HR, Tew JM Jr. Neurosurgery 1997; 40: 238- 44; discussion 245- 7 ( Feb). Over the past decade, one of the focal points of skull base surgery has been the attempt to treat lesions within the cavernous sinus. In this report, a retrospective review of 39 patients from the Skull Base Unit in Cincinnati, attempts at a relative conservative approach to cavernous sinus lesions were studied. Eight patients reportedly underwent complete tumor resection, and 31 patients underwent subtotal resection. There was no mortality in the series, but morbidity was reported at 18%, mainly involving the ocular motor nerves. The authors also noted failure of trigeminal function to improve after surgery. They concluded that resectability of meningiomas in the cavernous sinus was limited largely on the degree of internal carotid artery involvement and that morbidity is significant. The problem with this study, as well as other reports of surgery of meningiomas within the cavernous sinus, is the limitation in the duration of follow- up in lesions with a known slow growth pattern. In addition, it is important that adequate prospective data be accumulated on cranial nerve function, which is often worsened after aggressive surgical approach. The ideal treatment of meningiomas involving the cavernous sinus remains unclear, although certainly surgery in the area is possible. Surgeons and neuro- ophthalmologists must be familiar with the potential for exacerbation of cranial nerve dysfunction. The Treatment of Recurrent Unresectable and Malignant Meningiomas with Interferon Alpha- 2B. Kaba SE, DeMonte F, Bruner JM, Kyritsis AP, Jaeckle KA, Levin V, Yung WK. Neurosurgery 1997; 40: 271- 5 ( Feb). In the last and greatest of Harvey Cushing's monographs on meningiomas, he pointed out the futility of attempting complete cures of meningiomas when involving the skull base. Despite advances in surgical technique, this prediction of a high rate of recurrence has proved to be a major sticking point in the care of patients with skull base lesions. Attempts at medical therapy have so far been unrewarding. In this study of six patients with recurrent malignant meningioma or reportedly unresectable meningioma, treatment with recombinant interferon alpha- 2B reportedly demonstrated a " positive response" in five of the six patients. This response reportedly lasted from 6 to 14 months with minimal toxicity. Hopefully interferon- alpha may play a role in the treatment of otherwise progressive meningiomas. It also may suggest future avenues of development of effective chemofhera-peutic agents. Hydroxyurea for Treatment of Unresectable and Recurrent Meningiomas. I. Inhibition of Primary Human Meningioma Cells in Culture and in Meningioma Transplants by Induction of the Apoptotic Pathway. Schrell UM, Rittig MG, Anders M, Kiesewetter F, Marschalek R, Koch UH, Fahlbusch R. / Neurosurg 1997; 86: 845- 52 ( May). Although benign, meningiomas are extremely hard to eradicate. With their slow growth, it may take months or even years, but recurrence is frequent. The failure of surgical elimination has prompted the investigation of alternative means of treatment. Radiotherapy slows growth but may be associated with significant morbidity. In this study, a group from Germany explored the effect of hydroxyurea on meningioma cells in tissue culture. A remarkable decrease in cell proliferation was encountered. In a follow- up study, hydroxyurea inhibited the growth of human meningioma cells in nude mice by inducing apoptotic changes. Hydroxyurea for Treatment of Unresectable and Recurrent Meningiomas. II. Decrease in the Size of Meningiomas in Patients Treated with Hydroxyurea. Schrell UM, Rittig MG, Anders M, Koch UH, Marschalek R, Kiesewetter F, Fahlbusch R. J Neurosurg 1997; 86: 840- 4 ( May). In this follow- up clinical pilot study the authors present the first evidence that recurrent and unresectable meningiomas respond to hydroxyurea administered as a chemotherapeutic. Based on their previous experience in tissue culture in mice, the authors treated four patients with hydroxyurea. Tumors were found to regress in three cases and cease growth in the fourth. Although preliminary, this study has prompted the further study of the possible applicability of hydroxyurea to unrespectable meningiomas. In view of the poor previous experience in treating meningiomas with chemotherapeutic agents, this report is exciting and needs to be followed up. Cystic Craniopharyngioma: Long- Term Results after Intracavitary Irradiation with Stereotactically Applied Colloidal Beta- Emitting Radioactive Sources, Voges J, Sturm V, Lehrke R, Treuer H, Gauss C, Ber-thold F. Neurosurgery 1997; 40: 263- 9; discussion 269- 70 ( Feb). Along with meningiomas, craniopharyngiomas are extraordinarily hard to eradicate. Epithelial adhesion to critical structures including the optic nerve, chiasm, and vascular system often prevents complete excision. External radiotherapy also has proven less than ideal, and an additional attempt at treating these patients has been the installation of colloidal beta- admitting radioactive sources. In this long- term follow- up of 70 patients with cystic craniopharyngiomas, treatment with beta- emitting J Neuro- Opktliatniot, Vol, 17, No. 4, 1997 LITERATURE ABSTRACTS 289 isotopes, yttrium 90, and phosphorus 32 resulted in significant decrease in progression. Four patients treated with rhenium 186 did not seem to respond. Visual defects were the most common finding in these patients; they were improved in 23 patients and reportedly stabilized in 15, However, there was complete loss of vision in three patients, worsening of visual fields in one, and development of a third nerve palsy in one. The authors conclude that intracavitary treatment with beta- emitting radioactive sources may be effective in treatment of residual cystic- craniopharyngiomas. Carboplatin and Vincristine Chemotherapy for Children with Newly Diagnosed Progressive Low- Grade Gliomas. Packer PJ, Ater J, Allen J, Phillips P, Geyer R, Nicholson HS, Jakacfci R, Kurczynski E, Needle M, Fin-lay J, Reaman G, Boyett JM. J Neurosurg 1997; 86: 747- 54 ( May). Optimal therapy for progressive gliomas in childhood has yet to be defined. Radiotherapy has been used in the past but has significant morbidity, especially in the ex-tremely young population. In this study, the pediatric oncology group from Washington has used a carboplatin and vincristine chemotherapeutic regimen. Response was good over the entire population of 78 children, although better in children < 5 years of age. When gliomas of childhood progress, this form of chemotherapeutic intervention may slow growth with substantially less morbidity than radiotherapy. This improved response in the younger patients could argue for earlier intervention. Treatment for Intracranial Dural Arteriovenous Malformations- A Meta- analysis from the English Language Literature. Lucas CP, Zabramski JM, Spetz-ler RF, Jacobowitz R. Neurosurgery 1997; 40: 1119- 1130 ( Jun). With the advent of interventional neuroradiologic techniques, the potential treatment options in dealing with intracranial or dural arteriovenous malformations has increased. These now include surgical ligation of feeding vessels, endovascular procedures, surgical obliteration, radiosurgery, or a combination of more than one of the above treatments. In this meta- analysis review of 258 patients ( 248 from published series and 10 from the Barrow Neurologic Institute in Phoenix), results of treatment of dural arteriovenous malformations were analyzed after being divided into six categories by location. In patients with transverse- sigmoid sinus dural arteriovenous malformations, endovascular treatment alone was less efficacious than endovascular treatment combined with surgical resection. This was also true for those of die tentorial incisura. Lesions primarily involving the cavernous sinus were best treated endovascularly with success rates of 62% and 78% reported for transarterial and transvenous approaches, respectively. The authors concluded that there was no indication for simple ligation of feeding vessels because success rates varied between 0% and 8%. Dural arteriovenous malformations often present with neuro- ophthalmic signs or symptoms related to increased intracranial pressure and local ischemic effects secondary to steel. Knowledge of the effectiveness of treatment is important for neuro- oph-thalmologists in guiding appropriate selection of those responsible for treatment. A Randomized, Double- Blind, Vehicle- Controlled Trial of Tirilazad Mesylate in Patients with Aneurysmal Subarachnoid Hemorrhage; A Cooperative Study in North America. Haley EC Jr, Kassell NF, Appers on- Hansen C, Maile MH, Alves WM. J Neurosurg 1997; 86: 467- 74 ( Mar). The development of nonglucocorticoid 21 amino steroids has been anxiously investigated as a potential therapeutic agent in patients with head trauma and now in patients with aneurysmal subarachnoid hemorrhage. This report gives the results of 902 patients prospectively randomized in a double- blind control trial at 54 North American neurosurgical centers. Patients were treated within 48 h of subarachnoid hemorrhage continued through 10 days posthemorrhage. All patients were treated in conjunction with orally administered Nimo-dipine. The report demonstrated no statistically significant difference with regard to mortality or morbidity during the 3- month period after subarachnoid hemorrhage. The authors thus concluded diat tirilazad did not seem to improve the overall outcome in patients after aneurysmal subarachnoid hemorrhage in this trial. This is in contrast to previously reported studies from Europe, Australia, and New Zealand, which did suggest diat this drug resulted in improvement in morbidity. Obviously the jury has yet to come in on the use of 21 amino steroids in preventing vasospasm and die complications of subarachnoid hemorrhage. This report certainly puts a damper on initial enthusiasm. Because vasospasm remains a significant cause of late morbidity in patients after subarachnoid hemorrhage, it is imperative that continued investigation be conducted with regard to possible treatment. Guglielmi Detachable Coil Embolization of Acute Intracranial Aneurysm: Perioperative Anatomical and Clinical Outcome in 403 Patients. Vinuela F, Duck-wiler G, Mawad M. J Neurosurg 1997; 86: 475- 82 ( Mar). Guglielmi detachable coils have become the standard treatment of vascular lesions requiring thrombosis. This report summarizes the results in 403 patients treated at J Neuro- Ophihalmot. Vol 17, No. 4, 1997 290 LITERATURE ABSTRACTS eight centers for acute subarachnoid hemorrhage associated with a ruptured intracranial aneurysm. Reported complete aneurysm occlusion was observed in 71% of small aneurysms with a limited neck, 35% of large aneurysms, and 50% of giant aneurysms. A word of caution was raised by a residual " small neck remnant" in 21% of small aneurysms, 57% of large aneurysms, and 50% of giant aneurysms. Previous experience suggests that this may serve as a nidus for distal embolization. Complications were low throughout the series with aneurysm perforation, parent artery occlusion, and cerebral embolization occurring in 3% or less. The authors report a 9% immediate morbidity rate with 2% mortality related to technical complications. The detachable coil system remains a reasonable, safe alternative to surgical clipping, especially in those patients considered too ill for surgical intervention or after unsuccessful attempts at surgery. Endovascular Treatment of Acutely Ruptured and Unruptured Aneurysms of the Basilar Bifurcation. Raymond J, Roy D, Bojanowski M, Moumdjian R, L'Esperance G. J Neurosurg 1997; 86: 211- 9 ( Feb). The morbidity in the surgical approach to basilar tip aneurysms made these some of the most difficult to treat. The authors report the Montreal experience in endovascular treatment of 31 cases of basilar tip aneurysms. This approach is not without morbidity. There were seven technical complications and one death after treatment. Using Gugliemi detachable coils ( GDC), however, it was possible to occlude the aneurysm with immediate angiographic results considered by the authors to be " satisfactory" in 94% of patients and complete obliteration in 42%. Long- term follow- up demonstrated some loss of complete effect with only 30% of 27 patients studied at 6 months, demonstrating complete occlusion. Treatment with further GDC coils was possible. Although the ultimate role of endovascular techniques and the treatment of aneurysms remains undetermined, it is clear that this offers additional therapeutic modality in the treatment of often difficult vascular anomalies. Embolization of the Nidus of Brain Arteriovenous Malformations with n- butyl Cyanoacrylate. Debrun GM, Aletich V, Ausman JI, Charbel F, Dujovny M. Neurosurgery 1997; 40: 112- 20; discussion 120- 1 ( Jan). The initial neurointerventional approach to arteriovenous malformations was largely that of arterial embolization. The potential problems with recanalization and further vessel recruitment has led to the increasing use of transvenous approach to these lesions. In this study, Debrun, one of the earliest pioneers in interventional neuroradiology, suggests the use of nidus embolization with cyanoacrylate glue. Cyanoacrylate has been used before in embolization, but ran significant potential risks, including that of gluing the catheter into position. Debrun has added several changes in standard practice, including the use of specifically designed catheters. This and other techniques serves to increase the spectrum of treatments available for arteriovenous malformations. Glue's role will await additional studies. Effect of Transluminal Angioplasty on Cerebral Blood Flow in the Management of Symptomatic Vasospasm Following Aneurysmal Subarachnoid Hemorrhage. Firiik AD, Kaufmann AM, Jungreis CA, Yonas H. J Neurosurg 1997; 86: 830- 9 ( May). Interventional neuroradiologic procedures are playing an increasing role in treatment of patients with multiple types of vascular lesions. One of the significant persistent causes of morbidity associated with subarachnoid hemorrhage has been the onset of vasospasm. This is presumably related to me effect of subarachnoid blood. Multiple treatment modalities have been explored in the attempt to minimize its effect. In this study, 13 of 14 patients with angiographically demonstrated vasospasm were treatable with transluminal balloon angioplasty. There was evidence of angiographic improvement in all 13, with neurologic improvement in 12 of the 13. This study from Pittsburgh emphasizes the evolving usefulness of interventional radiologic techniques in the treatment of patients with subarachnoid hemorrhage. Isolated Straight Sinus and Deep Cerebral Venous Thrombosis: Successful Treatment with Local Infusion of Urokinase. Case Report. Holder CA, Bell DA, Lundell AL, Ulmer JL, Glazier SS, J Neurosurg 1997; 86: 704- 7 ( Apr). Venous sinus thrombosis is a rare cause of elevated intracranial pressure most frequently associated with infectious processes, especially involving the middle ear or mastoid. These can respond to anticoagulation plus medical or even surgical therapy for the secondary effects of the pressure elevation. In rare cases, acute deterioration may occur related to the thrombosis- induced acute pressure increase. Interventional neuroradiologic approach with urokinase in this particular case resulted in acceleration of clot lysis and improvement in the patient's overall function. More aggressive interventional therapy may be appropriate in the setting of clinical deterioration. J Neuro- Ophshaimol. Vol. 17, No. 4, 1997 Journal of Neuro- Ophthalmology 17( 4): 291, 1997. © 1997 Lippincott- Raven Publishers, Philadelphia Literature Abstracts- Europe Primary Localised Amyloidosis of the Orbit. Murdoch IE, Sullivan TJ, Moseley I, Hawkins PN, Pepys MB, Tan SY, Garner A, Wright JE. British Journal of Ophthalmology 1996,80: 1083- 6. [ Correspondence and reprint requests to Dr. I. Murdoch, Moorfields, Eye Hospital, London ECIV 2PD, UK, England. The differential diagnosis of a mass lesion in the orbit includes neoplastic and infectious diseases as well as inflammatory processes such as sarcoidosis and idiopathic orbital inflammatory disease. Primary localized amyloidosis is a rare disorder that should be considered, especially in elderly patients with no known history of malignancy and no sign of inflammatory disease. Three patients with primary localized amyloidosis were diagnosed using computed tomography, scintigraphy with I serum amyloid P component, and, finally, histologic examination. Simple debulking with subsequent observation was the treatment of choice. Treatment Selections of 239 Patients With Blepharospasm and Meige Syndrome Over 11 Years. Mauriello Jr, J A, Dhillon S, Leone T, Pakeman B, Mostafavi R, Yepez MC. British Journal of Ophthalmology 1996,80: 1073- 6. [ Correspondence and reprint requests to Dr. J. A. Mauriello, Jr., Department of Ophthalmology, UMDNJ, New Jersey Medical School, Doctors Office Center, 90 Bergen Street, Newark, NJ 07103, USA.] The authors report their experience with 239 patients with blepharospasm and Meige syndrome that were treated and followed over 11 years. Two hundred twenty- eight patients received local injections of botulinum A toxin over 11 years. Eight patients had an inadequate response to botulinum toxin. Five patients ( 2.2%) had apparent remission of their disease. Only three patients were treated surgically ( radical orbicularis myectomy). Eleven patients were not treated with botulinum toxin and chose other treatment modalities ( tranquilizer, muscle relaxant, antiseizure drugs). The premise of this comprehensive report is that botulinum A toxin injections still are the first- line treatment for blepharospasm and Meige syndrome. Resolution of this condition is rare, and additional medical therapy or surgery is required only in a small percentage of patients. Optic Nerve Diameters and Perimetric Thresholds in Idiopathic Intracranial Hypertension. Salgarello T, Tamburrelli C, Falsini B, Giudiceandrea A, Colotto A. British Journal of Ophthalmology 1996,80: 509- 14. [ Ad- H. Esriel Killer, M. D. dress correspondence and reprint requests to Dr. Tom-maso Salgarello, Institute of Ophthalmology, Catholic University, Largo F Vito, 1, 1- 00168 Rome, Italy.] Idiopathic intracranial hypertension, also called pseudotumor cerebri ( PTC), is characterized by loss of visual acuity and visual field from increased pressure within the sheath of the optic nerve. Standardized A- scan echography of the midorbital optic nerve diameter was performed in combination with automated threshold perimetry ( Humphrey 30- 2) in 20 patients with a diagnosis of PTC. Echographic and perimetric results were compared with 20 age- matched controls. When compared with controls, patients with PTC showed a significant increase in mean optic nerve diameter and significantly reduced mean perimetric sensitivities. The authors conclude that optic nerve diameter increase is associated with perimetric threshold loss. Functional deficits in PTC may therefore be related to the degree of distension of the optic nerve sheath caused by an increase in CSF pressure. Colour Doppler Imaging in Giant Cell ( Temporal) Arteritis: Serial Examination and Comparison With Non- Arteritic Anterior Ischaemic Optic Neuropathy Ghanchi FD, Williamson TH, Lim CS, Butt Z, Baxter GM, McKillop G, Brien CO. Eye 1996,10: 459- 64. [ Address correspondence and reprint requests to Faruque D. Ghanchi, Tennent Institute of Ophthalmology, Western Infirmary, Church Street, Glasgow Gil 6NT, UK.] The final diagnosis of giant cell arteritis ( GCA) is based on histopathologic findings. The blood sedimentation rate and the level of the C- reactive protein can be helpful in monitoring the activity of the disease process. The effect of GCA on orbital blood flow measured with color doppler imaging was investigated in this study on seven patients with GCA and four patients with non-arteritic anterior ischemic optic neuropathy. Blood flow was absent in up to three arteries in the affected orbits of six GCA patients at presentation. Five of these patients were found to have undetectable blood flow in the posterior ciliary arteries of the contralateral orbit. Despite treatment with corticosteroids blood flow, alterations were documented in serial CDI investigations. Return of blood flow to normal was slow and reflected the clinical features. 291 |