J.C.Maroon, et al: Cryosurgery re-visited for the removal and destruction of brain, spinal and orbital tumors. Neurological Research 14: 294-302, 1992.

Advances in neuroimaging and cryosurgical techniques have prompted us to re-evaluate the potential of cryosurgical techniques for the removal and the destruction of various neoplasms. We have used cryosurgical instrumentation to remove tumors in the brain, spine and orbit in 71 patients without complications. Cryosurgery was used to facilitate removal and extraction in 64 and to destroy residual neoplasms when removal was incomplete in 7. lntraoperative real time ultrasonic imaging permitted precise delimitation of tumors from surrounding tissues and allowed monitoring during the production of cryosurgical lesions thus permitting heretofore unavailable visualization of the production of cryogenic lesions in the central nervous system. New cryosurgical instrumentation was used to produce lesions up to three times larger than similar sized probes previously available. Our results reconfirm that cryosurgery facilitates the removal of tumors in the brain, spinal cord and orbit, reduces blood loss in vascular tumors, and is effective in ablating residual neoplasms involving the superior saggital sinus, torcula and parasaggital areas. A Doppler flowmeter proved useful for monitoring saggital sinus blood flow during the production of cryosurgical ablation of residual tumor attached to the walls of the saggital sinus. Recent advances in ultrasonic and neuroimaging coupled with stereotactic techniques and improvements in cryosurgical instrumentation may prove useful in the future percutaneous destruction of selective intracranial neoplasms. [Neurol Res 1992; 14: 294-302]

John S. Kennerdell, et al: Use of the Carbon Dioxide Laser in the Management of Orbital Plexiform Neurofibromas. Ophthalmic Surgery Vol 21, No. 2: 138-140, 1990.

John S. Kennerdell, MD, Joseph C. Maroon, MD

ABSTRACT We present one of three cases in which we have used the carbon dioxide laser to successfully perform subtotal surgical removal of plexiform neurofibromas of the lid and orbit. (Ophthalmic Surgery Vol 21, No. 2: 138-140, 1990)

John S. Kennerdell, M.D., Joseph C. Maroon, M.D., James A. Garrity, M.D., and Adnan A. Abla, M.D.

Lymphangiomas of the ocular adnexa, especially those in the orbit, are difficult to treat because the unencapsulated tumor freely interdigitates with normal orbital tissue, obliterating any potential surgical plane. Because of the hemorrhagic and friable nature of the tumor, conventional surgical techniques are frequently complicated by bleeding. We used the C02 laser to remove these lesions subtotally by controlled vaporization in six patients (four girls and two boys, 5 to 17 years old). Three pupils remained dilated postoperatively because of damage to the ciliary nerves and symblepharon formation occurred in one case. None of these has produced any symptoms. In one case, however, laser treatment may have produced corneal anesthesia. (American J Ophthalmology 102: 308-314, 1986)

JOSEPH C. MAROON, M.D., AND JOHN S. KENNERDELL, M.D.

The authors review their experience with over 300 patients with orbital tumors, and summarize their surgical techniques and indications for each surgical approach. A fronto-orbital approach is described which is used for tumors with intracranial extension and for those located in the orbital apex and deep medial orbital compartment. Lateral micro-orbitotomy is used for tumors located in the superior, temporal, or inferior compartment of the orbit and those in the lateral apex. A medial microsurgical approach is used for tumors located medial to the optic nerve but not deep in the apex. By thus approaching tumors directly, optimal exposure is obtained and functional deficits are minimized. The pertinent surgical anatomy is illustrated and the technique of fine-needle aspiration biopsy is discussed. (J Neurosurg 60: 1226-1235, 1984)

Patrick A. Sibony, et al: Optic Nerve Sheath Meningiomas. Ophthalmology, Vol. 91, No. 11: 1313-1326, 1984.
PATRICK A. SIBONY, MD, HOWARD R. KRAUSS, MD, JOHN S. KENNERDELL, MD, JOSEPH C. MAROON, MD, THOMAS L. SLAMOVITS, MD

Abstract: A retrospective clinical study of optic nerve sheath meningiomas based on 22 patients showed that symptoms most commonly develop in women between the ages of 35 and 60 years. The most common presenting symptoms were decreased vision and transient visual obscurations. In the earliest stages, many patients presented with normal to mildly impaired acuity (despite subjectively decreased vision), optic disc edema and enlargement of the blind spot. Optic disc edema was frequently associated with retractile bodies indicative of chronic swelling. Optic disc edema preceded the development of optic atrophy. Another group of patients presented with a history of longstanding vision loss, visual acuity of 20/200 or worse and optic atrophy. Optociliary shunt vessels were late findings only seen in five patients. The most consistent visual field abnormality was peripheral constriction. Cecocentral scotomas were uncommon. Intracranial involvement was present in five patients. There were two patients with bilateral optic nerve sheath meningiomas without CT evidence of intracranial involvement. Computerized tomography was found to be indispensable in the diagnosis of optic nerve sheath meningiomas and the detection of intracranial involvement. Ophthalmology 91:1313-1326, 1984