AMERICAN SHARED HOSPITAL SERVICES REPORTS THIRD QUARTER RESULTS San Francisco, CA

AMERICAN SHARED HOSPITAL SERVICES

REPORTS THIRD QUARTER RESULTS

San Francisco, CA - November

13, 2017 - AMERICAN SHARED HOSPITAL SERVICES (NYSE AMERICAN:AMS) (the "Company"), a leading provider of turnkey

technology solutions for advanced radiosurgical and radiation therapy services, today announced financial results for the third

quarter and first nine months of 2017.

Third Quarter Results

For the three months ended September 30,

2017, rental income from medical services decreased 5.5% to $4,613,000 compared to rental income from medical services of $4,884,000

for the third quarter of 2016. Net income attributable to the Company for the third quarter of 2017 was $99,000, or $0.02 per share.

This compares to net income attributable to the Company for the third quarter of 2016 of $334,000, or $0.06 per share.

Third quarter revenue for the Company's

initial proton therapy system installed at The Marjorie and Leonard Williams Center for Proton Therapy at Orlando Health -

UF Health Cancer Center in Florida increased 17.0% to $935,000 compared to revenue of $799,000 for the third quarter of 2016.

Revenue for the Company's Gamma Knife operations

decreased 9.4% to $3,564,000 for the third quarter of 2017 compared to $3,933,000 for the third quarter of 2016. As previously

announced, AMS lost one of its Gamma Knife units due to the expiration of its contract term at the end of April 2017 and a second

unit in August 2017. The decrease in revenue from these two sites was only partially offset by revenue from two new sites, in Lima,

Peru and Lincoln, Nebraska, that began operations in the third quarter and are still early in the ramp-up phase. Excluding the

two sites whose contracts expired this year, Gamma Knife revenue increased 4.1% for this year's third quarter compared to the third

Rental income from medical services gross

margin for the third quarter of 2017 decreased to 40.8% of revenue, compared to rental income from medical services gross margin

of 49.1% of revenue for the third quarter of 2016, primarily reflecting the decrease in Gamma Knife revenue.

Operating income decreased to $439,000

for the third quarter of 2017 compared to operating income of $896,000 for the same period a year earlier. Income before

income taxes was $439,000 for the third quarter of 2017 compared to $899,000 for the third quarter of 2016. Non-GAAP pre-tax income,

net of income attributable to non-controlling interest, was $263,000 for the third quarter of 2017. This compares to non-GAAP

pre-tax income, net of income attributable to non-controlling interest, of $601,000 for the third quarter of 2016. Please refer

to the financial statements included with this press release for a reconciliation of GAAP to non-GAAP financial measures.

Adjusted EBITDA, a non-GAAP financial measure,

was $2,412,000 for the third quarter of 2017, compared to $2,831,000 for the third quarter of 2016.

For the nine months ended September 30,

2017, rental income from medical services increased 6.1% to $14,472,000 compared to rental income from medical services of $13,640,000

for the first nine months of 2016.

Proton therapy revenue increased 137.0%

to $2,953,000 for the first nine months of 2017 compared to $1,246,000 for the first nine months of 2016.

Excluding treatments at customer sites

lost due to the expiration of their contract terms in April 2017 and August 2017, Gamma Knife revenue decreased 0.5% for the first

nine months of 2017 compared to the first nine months of 2016.

Net income attributable to the Company

for the first nine months of 2017 was $505,000, or $0.09 per share. This compares to net income attributable to the Company for

the first nine months of 2016 of $478,000, or $0.09 per share.

Adjusted EBITDA, a non-GAAP financial measure,

was $7,577,000 for the first nine months of 2017, compared to $7,288,000 for the first nine months of 2016.

Balance Sheet Highlights

At September 30, 2017, cash and cash equivalents

was $1,665,000, compared to $3,121,000 at December 31, 2016. Shareholders' equity at September 30, 2017 was $28,188,000,

or $4.94 per outstanding share. This compares to shareholders' equity at December 31, 2016 of $27,173,000, or $4.97 per

Chairman and Chief Executive Officer Ernest

A. Bates, M.D., said, "Treatment volume at our proton therapy center at Orlando Health - UF Cancer Center increased to 940

fractions for this year's third quarter, up from 869 fractions for the same period a year ago but below the 1,189 fractions reported

for this year's second quarter. This slowdown in proton treatment volume appears to have run its course, as volume rebounded sharply

in October. Accordingly, we are optimistic that proton treatment volume for this year's fourth quarter will resume its upward

trend. We believe the pace of treatment volume has room to increase even further in 2018. We also are pleased to report that the

MEVION S250 proton system we supplied Orlando Health continues to perform flawlessly, with no unanticipated operating issues.

"We also are optimistic about a rebound

in our Gamma Knife business beginning in the fourth quarter, as the ramp-up in patient volume at our new sites in Lima, Peru and

Lincoln, Nebraska gathers momentum.

"Additionally, the Centers for

Medicare & Medicaid Services recently announced a 6% increase in the Medicare reimbursement rate for simple, intermediate

or complex proton treatments, and a 1.5% increase for Gamma Knife treatments, for 2018. These rate increases are a welcome

development and should make a positive contribution to our financial performance in the new year."

Earnings Conference Call

American Shared has scheduled a conference

call at 12:00 p.m. PDT (3:00 p.m. EDT) today. To participate in the live call, dial (800) 588-4973 at least 5 minutes prior to

the scheduled start time, and mention confirmation number 4597 0345. A simultaneous WebCast of the call may be accessed through

the Company's website, www.ashs.com, or www.streetevents.com (institutional investors). A replay will be available for 14 days

at these same internet addresses, or by dialing (888) 843-7419 and entering 4597 0345# when prompted.

American Shared Hospital Services provides

turnkey technology solutions for advanced radiosurgical and radiation therapy services. AMS is the world leader in providing Gamma

Knife radiosurgery equipment, a non-invasive treatment for malignant and benign brain tumors, vascular malformations and trigeminal

neuralgia (facial pain). The Company also offers proton therapy, and the latest IGRT and IMRT systems. AMS owns a common stock

investment in Mevion Medical Systems, Inc., developer of the compact MEVION S250 Proton Therapy System.

Safe Harbor Statement

This press release may be deemed to

contain certain forward-looking statements with respect to the financial condition, results of operations and future plans of American

Shared Hospital Services (including statements regarding the expected continued growth in volume of the MEVION S250 system, the

expansion of the Company's proton therapy business, and the timing of treatments by new Gamma Knife systems) which involve risks

and uncertainties including, but not limited to, the risks of variability of financial results between quarters, the risks of the

Gamma Knife and radiation therapy businesses, the risks of developing The Operating Room for the 21st Century program, the risks

of investing in Mevion Medical Systems, Inc., and the risks of the timing, financing, and operations of the Company's proton

therapy business. Further information on potential factors that could affect the financial condition, results of operations and

future plans of American Shared Hospital Services is included in the filings of the Company with the Securities and Exchange Commission,

including the Company's Annual Report on Form 10-K for the year ended December 31, 2016, its Quarterly Report on Form 10-Q for

the three months ended March 31, 2017 and June 30, 2017, and the definitive Proxy Statement for the Annual Meeting of Shareholders

held on June 27, 2017.

Non-GAAP Financial Measure

Neither Adjusted EBITDA nor non-GAAP pre-tax

income, the non-GAAP measures presented in this press release and supplementary information, is a measure of performance under

the accounting principles generally accepted in the United States ("GAAP"). These non-GAAP financial measures should

not be considered as substitute for, and investors should also consider, income before income taxes, income from operations, net

income attributable to the Company, earnings per share and other measures of performance as defined by GAAP as indicators of the

Company's performance or profitability. We use these non-GAAP financial measures as a means to evaluate period-to-period comparisons.

Our management believes that these non-GAAP financial measures provide meaningful supplemental information regarding our performance

by excluding certain expenses and charges that may not be indicative of the operating results of our recurring core business, such

as the loss on early extinguishment of debt. We believe that both management and investors benefit from referring to these non-GAAP

financial measures in assessing our performance.

Ernest A. Bates, M.D.,

Chairman and Chief Executive

Neil Berkman, (310) 477-3118