Bernard Chang

High-Resolution Microscopy Coil MR-Eye

The eye is involved in several pathologies where precise identification of the underlying condition is essential for the optimal patient care. This preliminary report presents the potential of high-resolution microscopy coil magnetic resonance imaging (HR-MRI) to undertake this task being actively used in the clinical setting. We used a commercially available MRI scanner and a microscopy surface coil. Exquisite anatomic detail of the eye and orbit with depiction of previously unobserved structures and clear demonstration of the underlying pathology was achieved. This report supports the idea that orbital imaging can be revolutionized with the introduction of HR-MRI with broad clinical implications.

Use of high-resolution microscopy coil MRI for depicting orbital anatomy.

Objective: High-resolution MRI (HR-MRI) is a powerful non-invasive tool that provides images of higher spatial resolution and enables visualization of tissues previously unidentified with conventional techniques. The utilization of HR-MRI in the eye and orbit is essential due to the minute structure with great tissue diversity. The purpose of this study is to investigate the use of a novel surface coil and to explore the potential of this approach to depict normal anatomy. Methods: MR images were acquired using a commonly available 1.5T scanner. Ten normal volunteers were imaged using a surface microscopy coil of 47 mm inner diameter. T1- and T2-weighting and fat suppression techniques were used. HR-MR images were compared with conventional head coil MR images. Results: Overall exquisite anatomic detail of the eye and orbit is revealed. The in-plane resolution was 312 μ m and the displayed pixel dimension 156 μ m. Previously unobserved distinction of the globe layers and muscle groups is possible. To our best knowledge, our group was the first to demonstrate Tenons capsule and the tarsal plate with MRI. The ciliary body and zonules of the lens are clearly visible. The superior muscle group is illustrated, being apparently divided into its components, namely the superior rectus and the levator palpebrae superioris muscles. Finally, the retrobulbar fat and parts of its connective tissue are depicted. Conclusion: High-resolution microscopy coil MRI improves the image resolution dramatically and enables a detailed tissue depiction of the orbital and globe structures. Therefore, its introduction in routine clinical use can facilitate diagnosis and pre-operative planning in challenging cases.

Enophthalmos associated with primary breast carcinoma.

BACKGROUND AND OBJECTIVE The most common source of metastases to the orbit is from breast carcinoma.The orbital presentation can be the presenting sign of the cancer. Proptosis or exophthalmos is the more usual way metastases present, associated with ocular motility problems or diplopia. We present a case of enophthalmos associated with breast carcinoma whereby there is as yet no radiological evidence of an actual orbital metastatic lesion. PATIENTS AND METHODS A 51-year-old Caucasian woman with a known history of breast cancer presented with a 10-month history of vertical diplopia, particularly on upgaze. She noted that her left eye was becoming more “sunken” and examination confirmed an 8-mm enophthalmos on that side with restricted vertical eye movements and abduction. RESULTS A provisional diagnosis of metastatic breast cancer was made. CT and MRI scans were performed.The main feature noted was that of orbital fat atrophy with no evidence of an orbital mass. She has been followed up for a period of 21/2 years with 6-monthly scans.There has been no progression of her clinical signs and no orbital lesion found so far.We are continuing to review her. CONCLUSION Although no actual orbital mass has been found yet, we are treating her case as enophthalmos associated with scirrhosing breast carcinoma; she may, however, have spontaneous orbital fat atrophy, triggered by the cancer.

Beware the empty curette

BACKGROUND AND OBJECTIVE Chalazions are a common occurrence in the eyelids due to chronic inflammation in the tarsal plate. Treatment of non-resolving cases may involve incision and curettage. Chalazions that are recurrent should arouse suspicion. We present a case of a pleomorphic adenoma of the palpebral portion of the lacrimal gland, which was misdiagnosed as a chalazion. PATIENT AND METHODS A 41-year-old Caucasian lady initially presented with a swelling in the outer part of her right upper eyelid. A diagnosis of chalazion was made and two attempts at incision and curettage failed to resolve the lesion. She was then referred to the oculoplastics/adnexal unit. A more detailed examination revealed involvement of the palpebral part of her lacrimal gland. A CT-scan confirmed this and she proceeded to have a lateral orbitotomy to remove the tumour. RESULT Histological confirmation of a pleomorphic adenoma of the palpebral portion of the lacrimal gland was obtained. The lacrimal gland had been completely excised. CONCLUSION Persistent or recurrent meibomian cyst should be treated with suspicion. A careful orbital examination including lid eversion should always be performed to outrule a more sinister pathology.

Rapidly enlarging eyelid mass.

Figure. A, Large upper-eyelid pilomatrixoma associated with mechanical ptosis and reddish discoloration of the skin; small chalky nodules can be seen through the skinB, Computed tomography. A 5-year-old girl presented to her primary care physician with a large rapidly enlarging right upper eyelid mass after an accidental trauma to the eyebrow area. The child was otherwise well with no history of constitutional symptoms or pain. Medical history was unremarkable. An initial diagnosis of a nonresolving hematoma was made. After a history of rapid growth over 12 weeks after the initial trauma she was referred to our eye institution (Figure, A). Visual acuity was normal, with no afferent pupillary defect. Findings of the physical examination showed mechanical ptosis with no eyelid erythema, edema, or tenderness. There was a solitary oval-shaped subcutaneous mass, which was firm to palpation. It was not freely mobile from the overlying skin which had reddish-to-blue discoloration with visible calcification. There was no globe proptosis or dystopia, and eye movements were normal. Fundoscopy showed no signs of optic neuropathy. Systemic examination was unremarkable except for an enlarged ipsilateral pre-auricular lymph node. Differential diagnosis included pilomatrixoma, pyogenic granuloma, epidermal and dermoid cyst, capillary hemangioma, juvenile xanthogranuloma, and rhabdomyosarcoma. Computed tomography (Figure, B) urgently was performed to exclude rhabdomyosarcoma. Imaging showed a well-defined superficial ovoid complex mass which enhanced avidly with intravenous contrast administration. It had a central non-enhancing component with few flecks of calcification. There was no intra-orbital extension or underlying bone involvement. Excision biopsy was expedited. The tumor was completely excised through a skin crease incision and submitted en bloc for diagnostic histology. This revealed a well-circumscribed oval nodule measuring 2.3 1.5 cm. There were no intraoperative or postoperative complications. Light microscopy showed sheets of basaloid cells with foci of characteristic shadow cells. Marked inflammatory reaction was noted, dominated by giant multinucleated cells. Histopathologic findings were consistent with a diagnosis of pilomatrixoma, with no evidence of malignancy. Complete surgical excision was curative with no evidence of tumor recurrence during the 6-month follow-up. Eyelid pilomatrixoma is a rare benign neoplasm tumor originating from the matrix of the hair root. It can occur almost anywhere on the body but has a propensity to occur in the head and neck region, often involving the eyelid or eyebrow. It is most commonly seen in children and adolescents, with a slight female predominance existing. Patients

Difficult indirect carotid-cavernous fistulas – alternative techniques to gaining access for treatment

Aims Carotid-cavernous fistulas (CCFs) are abnormal communications between the carotid arterial system and the cavernous sinus that occur mainly in elderly. Occasionally, treatment of indirect CCFs with conventional endovascular approach through large veins or the inferior petrosal sinus may not be possible. In these cases, a direct surgical cut down on to the superior ophthalmic vein (SOV) is necessary. We describe three such cases of embolization of CCFs through SOV, and their results. Methods A retrospective case notes review of treated patients over the past 10 years in one tertiary center constituted our methodology. Results The fistulas in two cases were successfully coiled with complete obviation of symptoms and signs. The third case was complicated due to difficulty in canulating a deeply seated vein and so had to be abandoned and catheterized through contralateral superior petrosal sinus and treated with liquid embolic material Onyx® successfully. Conclusion In cases where conventional access to the cavernous sinus may not be possible due to local variations of anatomy, multidisciplinary surgical approaches via the SOV provide an alternative route to successfully and safely close a CCF. However, unexpected anatomical variations could also be encountered within the SOV for which the surgeon should be prepared.

Multidisciplinary Management of Adult Orbital Rhabdomyosarcoma

ABSTRACT We report the case of a 52-year-old man who presented with a 10-day history of right eye and eyelid inflammation and intermittent diplopia following blunt trauma to the right eyebrow. The CT and MRI scans revealed an extraconal soft tissue mass on the orbital floor with maxillary and ethmoid sinus wall destruction, which on orbital biopsy was proven to be an Alveolar Rhabdomyosarcoma. The patient had a central retinal vein occlusion due to mass effect that resulted in total visual loss at 2 months. He was referred to oncologists who treated him according to the paediatric RMS protocol and is still in remission at 2-year follow-up. Rhabdomyosarcoma is a rare tumour in adults which requires multi-disciplinary management. This highlights the necessity of considering rhabdomyosarcoma in the differential diagnosis of orbital tumours in any age group.

Re: “Use of High Resolution Microscopy Coil MRI for Depicting Orbital Anatomy,” ORBIT issue 27.2 (page 107–114)—answer to reader comments

Received 12 December 2008; accepted 22 March 2009. Address correspondence to Bernard Chang, Consultant Ophthalmic Surgeon, Eye Department, Chancellor Wing, St. James’s University Hospital, Beckett Street, Leeds L59 7TF, UK. E-mail: bypchang@doctors.org.uk We also feel this is Whitnall’s ligament, as it is on top of the levator palpebrae superioris muscle. Whitnall’s ligament connects the orbital roof to the levator aponeurosis. Furthermore, we labelled the structure Whitnall’s ligament as per diagram/figures from previous MRI studies (Ettl et al., 1996; Hayman et al., 1995). Unfortunately, we cannot reproduce these due to copyright.

An indeterminate malignant soft-tissue tumour treated by exenteration

PURPOSE . To present a case of malignant soft-tissue tumour, which has yet to be categorised despite review by an international panel of experts, and which was treated by exenteration. PATIENT & METHODS . A 15-year-old Caucasian girl presented with progressive, non-axial proptosis and diplopia. CT scan showed an extraconal mass in the supero-medial part of the orbit suggestive of a vascular neoplasm. After initial incisional biopsy, the pathology of the tumour was felt to be malignant but so unique that further tissue was required for classification/categorisation and that exenteration was the best way to proceed. RESULTS . Despite there being an adequate amount of tissue and opinions being sought from international experts, including the Children¹s Soft Tissue Panel (of the United Kingdom), this tumour has yet to be categorised. Reports have suggested it to be anything from a malignant desmoplastic round-cell tumour or a synovial sarcoma to an epithelioid haemangioendothelioma, which is our current working diagnosis. CONCLUSION . This case is unique in that it has not been possible to classify the tumour. Categorisation is important in order to give a reasonably accurate prognosis to the patient. Exenteration was required to offer complete tumour excision and will hopefully prevent local recurrence and metastatic spread.

Standardized Photographic Views in Oculoplastic Surgery: How to Capture Quality Images Outside a Photographic Studio

Purpose The aim of this paper is to demonstrate fundamental photographic techniques and standardized views in oculoplastic disease and surgery outside of a photographic studio. Methods A Canon EOS 60D digital single lens reflex (DSLR) camera, which was fitted with a Canon EF-S 60 mm USM macro lens, was used to photograph the subject. A Canon MR-14EX Macro Ringlite was used to illuminate the subject. Informed written consent was obtained for publication of the photographs used in this study. The photographs were taken in an ophthalmology clinic using standardized photographic settings at various magnification ratios. The magnification ratios were recalibrated and adjusted to accommodate the smaller sensor size in-line with standardized medical photography guidelines. Results We present a series of core views for various oculoplastic and orbital disease presentations. Conclusions It is possible to capture quality standardized digital photographs in a busy clinical environment without the need for a dedicated photographic studio.